The promise of adaptive cancer immunotherapy in treating highly malignant tumors such as glioblas... more The promise of adaptive cancer immunotherapy in treating highly malignant tumors such as glioblastoma multiforme (GBM) can only be realized through expanding its benefits to more patients. Alleviating various modes of immune suppression has so far failed to achieve such expansion, but exploiting endogenous immune enhancers among mutated cancer genes could represent a more direct approach to immunotherapy improvement. We found that Isocitrate Dehydrogenase-1 (IDH1), which is commonly mutated in gliomas, enhances glioma vaccine efficacy in mice and discerns long from short survivors after vaccine therapy in GBM patients. Extracellular IDH1 directly enhanced T cell responses to multiple tumor antigens, and prolonged experimental glioma cell lysis. Moreover, IDH1 specifically bound to and exhibited sialidase activity against CD8. By contrast, mutant IDH1R132H lacked sialidase activity, delayed killing in glioma cells, and decreased host survival after immunotherapy. Overall, our findings identify IDH1 as an immunotherapeutic enhancer that mediates the known T cell-enhancing reaction of CD8 desialylation. This uncovers a new axis for immunotherapeutic improvement in GBM and other cancers, reveals novel physiological and molecular functions of IDH1, and hints at an unexpectedly direct link between lytic T cell function and metabolic activity in target cells.
For malignant gliomas, progress in molecular diagnostics such as genomewide sequencing led to ide... more For malignant gliomas, progress in molecular diagnostics such as genomewide sequencing led to identification of subgroup-defining genetic alterations representing promising immunotherapeutic targets especially for personalized vaccination strategies. One example for an oncogenic mutation occurring in about one half of all pediatric brain stem gliomas and occasionally in adult gliomas is a point mutation in the histon-3.3 gene (H3F3A) causing an amino acid exchange from lysine to methionine at position 27 (K27M). Here, we analyzed the immunogenicity of H3.3 K27M and its relevance for a mutation-specific vaccination approach. Vaccination of major histocompatibility complex (MHC)-humanized (A2DR1) mice with a H3.3 K27M-covering 10-mer peptide led to a CD8driven mutation-specific immune response. Using a human leukocyte antigen (HLA) class-I epitope prediction tool, a mutation-containing 10mer peptide sequence with a strong binding affinity compared to the corresponding wild type sequence was identified. In silico, functional presentation of the crucial epitope was predicted for the class-I haplotypes A2. Importantly, peptide vaccination of A2DR1-mice effectively inhibited growth of H3.3 K27Moverexpressing flank tumors. In summary, we demonstrated that a H3.3 K27M-specific and effective antitumor immune response can be induced by a peptide vaccine. Thus, our data provide evidence for a further clinical development of this personalized immunotherapeutic approach. OS2.
High grade gliomas are associated with poor prognosis and high mortality. Conventional treatments... more High grade gliomas are associated with poor prognosis and high mortality. Conventional treatments and management of high grade gliomas have shown little improvement in 5-year overall survival. This phase I trial evaluated the safety, immunogenicity, and potential synergy of surgical resection with Gliadel Wafer implantation, followed by autologous tumor lysate-pulsed dendritic cell (DC) vaccine in patients with malignant glioma. Primary end points of this study were safety and surrogate markers of immunogenicity, overall survival, and progression free survival. Following surgical resection, Gliadel Wafers were placed along the resection cavity. Patients subsequently received intradermal injections of autologous tumor lysate-pulsed DC vaccines 3 times at 2 week intervals. Treatment response was evaluated clinically and through MRI at regular intervals. Twenty-eight patients received Gliadel Wafers and DC vaccination: 11 newly diagnosed (8 glioblastoma [GBM], 2 anaplastic astrocytoma [AA], and 1 anaplastic oligodendroglioma [AO]) and 17 recurrent (15 GBMs, 1 AA, and 1 AO) high grade gliomas. Immunogenicity data was collected for 20 of the 28 patients. Five of 20 patients showed elevated IFN-c responses following vaccination. Median progression-free survival and overall survival for all GBM patients in the trial from the start of vaccination were 3.6 months and 16.9 months respectively. Comparisons between vaccine responders and non-vaccine responders were not statistically significant. Adjuvant autologous dendritic cells pulsed with tumor-lysate following resection and Gliadel Wafer placement is safe, elicits modest immunogenicity and shows similar clinical outcomes in patients who had DC vaccination in previous studies.
2033 Background: Our prior immunotherapy trials demonstrated efficacy in generating a tumor speci... more 2033 Background: Our prior immunotherapy trials demonstrated efficacy in generating a tumor specific immune response in malignant glioma and the potential for high tumor-specific toxicity and sustained tumoricidal activity. Immunotherapy may synergize with chemotherapy and biodegradable carmustine (BCNU) wafers extend overall survival from 11.6 to 13.9 months. Methods: We exploited this synergistic effect to maintain a cytotoxic environment around the tumor milieu. Patients with high-grade glioma were eligible after maximal resection with biodegradable carmustine (BCNU) wafer placement. Screening leukapheresis is used to isolate mononuclear cells which are differentiated into dendritic cells, pulsed with tumor lysate, and then 3 intradermal vaccines are administered at 2-week intervals. Patients continued systemic chemotherapy after vaccine or at progression. Results: Eighteen patients have been enrolled (7 Male, 11 Female) between April 2007 and February 2009 with one screen failure and two patients with clinical progression prior to vaccination. The median patient age was 57 years (26 to 74 ) and median Karnofsky performance status was 90% (80–100). The histology included 3 newly diagnosed glioblastoma multiforme (GBM), 8 recurrent GBM, 2 newly diagnosed anaplastic astrocytoma (AA), and 2 recurrent AA. 15 patients were successfully treated by vaccine injections with 12 patients receiving vaccine every 2 weeks x 3 followed by adjuvant chemotherapy. Our preliminary data on 15 patients and 39 courses of Dendritic Cell vaccines demonstrate one grade 3 toxicity of fever/chest pain. A stable disease interval of 13 to 90 weeks was observed for patients who received vaccine. The 3 newly diagnosed GBM patients have stable disease (18 to 71 weeks). In the recurrent GBM cohort 7/8 patients had progression within 6 months from the post-vaccination MRI. Conclusions: This phase I study demonstrates the safety, feasibility of dendritic cell vaccination with biodegradable carmustine (BCNU) wafers with one grade 3 AE. Immunological data is pending to determine potential synergy of dendritic cell vaccination with intracranial chemotherapy. No significant financial relationships to disclose.
2084 Background: Our prior immunotherapy trials demonstrated efficacy in generating a tumor speci... more 2084 Background: Our prior immunotherapy trials demonstrated efficacy in generating a tumor specific immune response in malignant glioma and the potential for high tumor-specific toxicity and sustained tumoricidal activity. Immunotherapy may synergize with chemotherapy and biodegradable carmustine (BCNU) wafers and have a modest impact to extend overall survival. We exploited this synergistic effect to maintain a cytotoxic environment around the tumor milieu, and this is a presentation of the final results of our clinical trial. Methods: Patients with glioblastoma were eligible after maximal resection with biodegradable carmustine (BCNU) wafer placement. Screening leukapheresis was used to isolate mononuclear cells which were differentiated into dendritic cells, pulsed with tumor lysate, and then 3 intradermal vaccines administered at 2-week intervals. Patients continued systemic chemotherapy after vaccine or at progression. Results: Twenty three patient with glioblastoma received therapy including 8 with newly diagnosed disease (35%) and 15 with recurrent disease (65%) were evaluable. Immune response data is available for 20/23 patients although survival data is present for all. One grade 3 SAE of fever and chills was noted otherwise therapy was well tolerated. Within the newly diagnosed GBM cohort the median overall survival (OS) was 25.5 months (15,31+), and within the recurrent GBM cohort, the median OS was 16 months (8,23+). Among the recurrent GBM an increase of >1.5 X baseline interferon gamma production post vaccination was associated with a prolonged median OS 22 months (8,40) in 4/12 patients versus 17 months (9,27) in 8/12 patients. Conclusions: We were able to generate an immune response in 25% of patients which is lower than what we have seen in previous trials and suggests a limited synergy with local control. However, within the recurrent GBM cohort we did find prolonged survival in both groups with an increased survival noted in immune responders demonstrating the potential for this therapy.
The incidence of autism spectrum disorders (ASD) and attention deficit hyperactivity disorder (AD... more The incidence of autism spectrum disorders (ASD) and attention deficit hyperactivity disorder (ADHD), which frequently co-occur, are both rising. The causes of ASD and ADHD remain elusive, even as both appear to involve perturbation of the gut-brain-immune axis. CD103 is an integrin and E-cadherin receptor most prominently expressed on CD8 T cells that reside in gut, brain, and other tissues. CD103 deficiency is well-known to impair gut immunity and resident T cell function, but it's impact on neurodevelopmental disorders has not been examined. We show here that CD8 T cells influence neural progenitor cell function, and that CD103 modulates this impact both directly and potentially by controlling CD8 levels in brain. CD103 knockout (CD103KO) mice exhibited a variety of behavioral abnormalities, including superior cognitive performance coupled with repetitive behavior, aversion to novelty and social impairment in females, with hyperactivity with delayed learning in males. Brain protein markers in female and male CD103KOs coincided with known aspects of ASD and ADHD in humans, respectively. Surprisingly, CD103 deficiency also decreased age-related cognitive decline in both sexes, albeit by distinct means. Together, our findings reveal a novel role for CD103 in brain developmental function, and identify it as a unique factor linking ASD and ADHD etiology. Our data also introduce a new animal model of combined ASD and ADHD with associated cognitive benefits, and reveal potential therapeutic targets for these disorders and age-related cognitive decline.
2087 Background: This study evaluated the safety and immune responses to an autologous dendritic ... more 2087 Background: This study evaluated the safety and immune responses to an autologous dendritic cell vaccine pulsed with class I peptides from tumor associated antigens (TAA) expressed on gliomas and overexpressed in their cancer stem cell population (ICT-107). These TAA epitodes AIM-2. TRP-2, HER2 and AIM-2, are also overexpressed on glioblastoma multiforme (GBM) cancer stem cells. Methods: TAA epitopes included HER2, TRP-2, gp100, MAGE-1, IL13Rα2, and AIM-2. HLA-A1 and/or HLA-A2 positive glioblastoma (GBM) patients with gross total resection were eligible. Mononuclear cells from leukapheresis were differentiated into dendritic cells, pulsed with TAA peptides, and administered intradermally three times at two-week intervals in the axilla region after a standard treatment with concurrent temozolomide (TMZ) and radiation therapy for newly diagnosed (ND-GBM). Results: Twenty-one patients were enrolled with 17 ND-GBM and three recurrent GBM patients and one brainstem glioma. Immune re...
Surgery of benign intradural extra-axial tumors in- volving the clivus and craniospinal region is... more Surgery of benign intradural extra-axial tumors in- volving the clivus and craniospinal region is extremely demanding due to the close relationships between these tumors and vital neurovascular structures and to their frequent extension to adjacent areas. These factors call for surgical approaches that are wide enough to gain access to multiple contiguous topographic regions, multiangled to vary the surgical angle to different parts of the tumor, and that allow full control of neurovascular structures while minimizing the amount of brain retraction. In this milieu 193
IL-23 is a recently discovered cytokine consisting of a heterodimer of the IL-12 p40 subunit and ... more IL-23 is a recently discovered cytokine consisting of a heterodimer of the IL-12 p40 subunit and a novel 19-kDa protein, termed p19. IL-23 preferentially induces proliferation of, and IFN-γ production by, memory T cells. In the present study, we transduced freshly cultured dendritic cells (DC) with an adenoviral vector carrying the single-chain IL-23 cDNA. Message RNA and protein expression of IL-23 from the transduced DC were detected by RT-PCR and ELISA respectively. Intratumoral implanting IL-23 expressing DC into intracranial GL-26 glioma bearing C57bl/6 mice resulted in prolonged survival compared with the control mice, which were intracranial bearing GL-26 glioma implanted with empty vector transduced DC. Enhanced CD8 + T cells infiltration within the tumors were detected by immunohistochemistry in brain sections from the mice treated by IL-23 expression DC. Cytotoxic T lymphocyte (CTL) assay of the spleen cells from the IL-23 expressing DC treated mice shown that CTL activities against GL-26 glioma but not irrelevant tumors were augmented. In addition, the mice survived intracranial glioma by IL-23 expressing DC treatment were resistant to intracranial rechallenge with the same GL-26 cell line. This tumor-specific protective immunity was associated with enhanced IFN-γ expression in the brain. Furthermore, the antitumor activities of IL-23 expressing DC was also observed in athymic nude mice but greatly impaired compared with that in C57bl/6 mice. Natural killer cells depletion for the athymic nude mice abolished the antitumor function. Taken together, these data suggest that DC as powerful antigen presenting cells can elicit tumor-specific antitumor immune responses after transduced by IL-23. T cells are crucial for the antitumor activity of the IL-23 expressing DC and natural killer cells are also involved in the process.
Object. An approach toward the treatment of intracranial gliomas was developed in a rat experimen... more Object. An approach toward the treatment of intracranial gliomas was developed in a rat experimental model. The authors investigated the ability of “professional” antigen-presenting cells (dendritic cells) to enhance host antitumor immune responses when injected as a vaccine into tumor-bearing animals.Methods. Dendritic cells, the most potent antigen-presenting cells in the body, were isolated from rat bone marrow precursors stimulated in vitro with granulocyte—macrophage colony-stimulating factor (GM-CSF) and interleukin-4. Cultured cell populations were confirmed to be functional antigen-presenting cells on the basis of expressed major histocompatibility molecules, as analyzed by fluorescence-activated cell sorter cytofluorography. These dendritic cells were then pulsed (cocultured) ex vivo with acid-eluted tumor antigens from 9L glioma cells. Thirty-eight adult female Fischer 344 rats harboring 7-day-old intracranial 9L tumors were treated with three weekly subcutaneous injection...
Immune-based therapy confers limited benefits to hosts bearing late-stage tumors. Mounting eviden... more Immune-based therapy confers limited benefits to hosts bearing late-stage tumors. Mounting evidence points to local suppression of T cell function as the most substantial barrier to effective antitumor immunity in hosts with large tumor burdens. Despite this, events responsible for locally defective T cells and immune suppression in tumors remain unclear. We describe in this study a predominant T cell population localized within two murine tumors that is characterized by expression of apoptotic markers and TCRαβ/CD3, but not CD4, CD8, or NK-associated markers. These defective cells resembled double negative (DN) T cells in lpr mice, harbored defects in the expression of T cell signaling molecules, and produced the anti-inflammatory cytokine, IL-10. Conditions known to increase or decrease the accumulation of lpr DN T cells had corresponding effects on local DN tumor infiltrating lymphocyte (TIL) levels and inversely impacted host survival. Adoptive transfer into s.c. tumors demonstr...
For unknown reasons, advanced age remains a dominant predictor of poor clinical outcome for nearl... more For unknown reasons, advanced age remains a dominant predictor of poor clinical outcome for nearly all cancers. A decrease in the production of T cells by the thymus accompanies normal aging and parallels the age-dependent increase in cancer progression, but the specific impact of immunity on tumor progression in general is unknown. Glioblastoma multiforme (GBM), the most common primary brain neoplasm, is characterized by rapid age-dependent rates of progression and death. In this study, we show levels of CD8+ recent thymic emigrants (RTEs) accounted for the prognostic power of age on clinical outcome in GBM patients. CD8+ RTEs, typically a tiny proportion of CD8+ T cells, remarkably accounted for the majority of tumor Ag-binding small precursor cells in PBMC from these patients and from healthy individuals. Large blasting tumor Ag-binding cells comprised of CD8+ RTEs and phenotypically related cells were predominantly expanded following experimental vaccination of GBM patients. Qua...
Cancer vaccine trials have failed to yield robust immune-correlated clinical improvements as obse... more Cancer vaccine trials have failed to yield robust immune-correlated clinical improvements as observed in animal models, fueling controversy over the utility of human cancer vaccines. Therapeutic vaccination represents an intriguing additional therapy for glioblastoma multiforme (GBM; grade 4 glioma), which has a dismal prognosis and treatment response, but only early phase I vaccine trial results have been reported. Immune and clinical responses from a phase II GBM vaccine trial are reported here. IFN-γ responsiveness was quantified in peripheral blood of 32 GBM patients given therapeutic dendritic cell vaccines. Posttreatment times to tumor progression (TTP) and survival (TTS) were compared in vaccine responders and nonresponders and were correlated with immune response magnitudes. GBM patients (53%) exhibited ≥1.5-fold vaccine-enhanced cytokine responses. Endogenous antitumor responses of similar magnitude occurred in 22% of GBM patients before vaccination. Vaccine responders exhi...
Background This study evaluated the safety and immune responses to an autologous dendritic cell v... more Background This study evaluated the safety and immune responses to an autologous dendritic cell vaccine pulsed with class I peptides from tumor-associated antigens (TAA) expressed on gliomas and overexpressed in their cancer stem cell population (ICT-107). Methods TAA epitopes included HER2, TRP-2, gp100, MAGE-1, IL13Ra2, and AIM-2. HLA-A1-and/or HLA-A2positive patients with glioblastoma (GBM) were eligible. Mononuclear cells from leukapheresis were differentiated into dendritic cells, pulsed with TAA peptides, and administered intradermally three times at two-week intervals. Results Twenty-one patients were enrolled with 17 newly diagnosed (ND-GBM) and three recurrent GBM patients and one brainstem glioma. Immune response data on 15 newly diagnosed patients showed 33 % responders. TAA expression by qRT-PCR from fresh-frozen tumor samples showed all patient tumors expressed at least three TAA, with 75 % expressing all six. Correlations of increased PFS and OS with quantitative expression of MAGE1 and AIM-2 were observed, and a trend for longer survival was observed with gp100 and HER2 antigens. Target antigens gp100, HER1, and IL13Ra2 were downregulated in recurrent tumors from 4 HLA-A2? patients. A decrease in or absence of CD133 expression was seen in five patients who underwent a second resection. At a median follow-up of 40.1 months, six of 16 ND-GBM patients showed no evidence of tumor recurrence. Median PFS in newly diagnosed patients was 16.9 months, and median OS was 38.4 months. Conclusions Expression of four ICT-107 targeted antigens in the pre-vaccine tumors correlated with prolonged overall survival and PFS in ND-GBM patients. The goal of targeting tumor antigens highly expressed on glioblastoma cancer stem cells is supported by the observation of decreased or absent CD133 expression in the recurrent areas of gadolinium-enhanced tumors.
The promise of adaptive cancer immunotherapy in treating highly malignant tumors such as glioblas... more The promise of adaptive cancer immunotherapy in treating highly malignant tumors such as glioblastoma multiforme (GBM) can only be realized through expanding its benefits to more patients. Alleviating various modes of immune suppression has so far failed to achieve such expansion, but exploiting endogenous immune enhancers among mutated cancer genes could represent a more direct approach to immunotherapy improvement. We found that Isocitrate Dehydrogenase-1 (IDH1), which is commonly mutated in gliomas, enhances glioma vaccine efficacy in mice and discerns long from short survivors after vaccine therapy in GBM patients. Extracellular IDH1 directly enhanced T cell responses to multiple tumor antigens, and prolonged experimental glioma cell lysis. Moreover, IDH1 specifically bound to and exhibited sialidase activity against CD8. By contrast, mutant IDH1R132H lacked sialidase activity, delayed killing in glioma cells, and decreased host survival after immunotherapy. Overall, our findings identify IDH1 as an immunotherapeutic enhancer that mediates the known T cell-enhancing reaction of CD8 desialylation. This uncovers a new axis for immunotherapeutic improvement in GBM and other cancers, reveals novel physiological and molecular functions of IDH1, and hints at an unexpectedly direct link between lytic T cell function and metabolic activity in target cells.
For malignant gliomas, progress in molecular diagnostics such as genomewide sequencing led to ide... more For malignant gliomas, progress in molecular diagnostics such as genomewide sequencing led to identification of subgroup-defining genetic alterations representing promising immunotherapeutic targets especially for personalized vaccination strategies. One example for an oncogenic mutation occurring in about one half of all pediatric brain stem gliomas and occasionally in adult gliomas is a point mutation in the histon-3.3 gene (H3F3A) causing an amino acid exchange from lysine to methionine at position 27 (K27M). Here, we analyzed the immunogenicity of H3.3 K27M and its relevance for a mutation-specific vaccination approach. Vaccination of major histocompatibility complex (MHC)-humanized (A2DR1) mice with a H3.3 K27M-covering 10-mer peptide led to a CD8driven mutation-specific immune response. Using a human leukocyte antigen (HLA) class-I epitope prediction tool, a mutation-containing 10mer peptide sequence with a strong binding affinity compared to the corresponding wild type sequence was identified. In silico, functional presentation of the crucial epitope was predicted for the class-I haplotypes A2. Importantly, peptide vaccination of A2DR1-mice effectively inhibited growth of H3.3 K27Moverexpressing flank tumors. In summary, we demonstrated that a H3.3 K27M-specific and effective antitumor immune response can be induced by a peptide vaccine. Thus, our data provide evidence for a further clinical development of this personalized immunotherapeutic approach. OS2.
High grade gliomas are associated with poor prognosis and high mortality. Conventional treatments... more High grade gliomas are associated with poor prognosis and high mortality. Conventional treatments and management of high grade gliomas have shown little improvement in 5-year overall survival. This phase I trial evaluated the safety, immunogenicity, and potential synergy of surgical resection with Gliadel Wafer implantation, followed by autologous tumor lysate-pulsed dendritic cell (DC) vaccine in patients with malignant glioma. Primary end points of this study were safety and surrogate markers of immunogenicity, overall survival, and progression free survival. Following surgical resection, Gliadel Wafers were placed along the resection cavity. Patients subsequently received intradermal injections of autologous tumor lysate-pulsed DC vaccines 3 times at 2 week intervals. Treatment response was evaluated clinically and through MRI at regular intervals. Twenty-eight patients received Gliadel Wafers and DC vaccination: 11 newly diagnosed (8 glioblastoma [GBM], 2 anaplastic astrocytoma [AA], and 1 anaplastic oligodendroglioma [AO]) and 17 recurrent (15 GBMs, 1 AA, and 1 AO) high grade gliomas. Immunogenicity data was collected for 20 of the 28 patients. Five of 20 patients showed elevated IFN-c responses following vaccination. Median progression-free survival and overall survival for all GBM patients in the trial from the start of vaccination were 3.6 months and 16.9 months respectively. Comparisons between vaccine responders and non-vaccine responders were not statistically significant. Adjuvant autologous dendritic cells pulsed with tumor-lysate following resection and Gliadel Wafer placement is safe, elicits modest immunogenicity and shows similar clinical outcomes in patients who had DC vaccination in previous studies.
2033 Background: Our prior immunotherapy trials demonstrated efficacy in generating a tumor speci... more 2033 Background: Our prior immunotherapy trials demonstrated efficacy in generating a tumor specific immune response in malignant glioma and the potential for high tumor-specific toxicity and sustained tumoricidal activity. Immunotherapy may synergize with chemotherapy and biodegradable carmustine (BCNU) wafers extend overall survival from 11.6 to 13.9 months. Methods: We exploited this synergistic effect to maintain a cytotoxic environment around the tumor milieu. Patients with high-grade glioma were eligible after maximal resection with biodegradable carmustine (BCNU) wafer placement. Screening leukapheresis is used to isolate mononuclear cells which are differentiated into dendritic cells, pulsed with tumor lysate, and then 3 intradermal vaccines are administered at 2-week intervals. Patients continued systemic chemotherapy after vaccine or at progression. Results: Eighteen patients have been enrolled (7 Male, 11 Female) between April 2007 and February 2009 with one screen failure and two patients with clinical progression prior to vaccination. The median patient age was 57 years (26 to 74 ) and median Karnofsky performance status was 90% (80–100). The histology included 3 newly diagnosed glioblastoma multiforme (GBM), 8 recurrent GBM, 2 newly diagnosed anaplastic astrocytoma (AA), and 2 recurrent AA. 15 patients were successfully treated by vaccine injections with 12 patients receiving vaccine every 2 weeks x 3 followed by adjuvant chemotherapy. Our preliminary data on 15 patients and 39 courses of Dendritic Cell vaccines demonstrate one grade 3 toxicity of fever/chest pain. A stable disease interval of 13 to 90 weeks was observed for patients who received vaccine. The 3 newly diagnosed GBM patients have stable disease (18 to 71 weeks). In the recurrent GBM cohort 7/8 patients had progression within 6 months from the post-vaccination MRI. Conclusions: This phase I study demonstrates the safety, feasibility of dendritic cell vaccination with biodegradable carmustine (BCNU) wafers with one grade 3 AE. Immunological data is pending to determine potential synergy of dendritic cell vaccination with intracranial chemotherapy. No significant financial relationships to disclose.
2084 Background: Our prior immunotherapy trials demonstrated efficacy in generating a tumor speci... more 2084 Background: Our prior immunotherapy trials demonstrated efficacy in generating a tumor specific immune response in malignant glioma and the potential for high tumor-specific toxicity and sustained tumoricidal activity. Immunotherapy may synergize with chemotherapy and biodegradable carmustine (BCNU) wafers and have a modest impact to extend overall survival. We exploited this synergistic effect to maintain a cytotoxic environment around the tumor milieu, and this is a presentation of the final results of our clinical trial. Methods: Patients with glioblastoma were eligible after maximal resection with biodegradable carmustine (BCNU) wafer placement. Screening leukapheresis was used to isolate mononuclear cells which were differentiated into dendritic cells, pulsed with tumor lysate, and then 3 intradermal vaccines administered at 2-week intervals. Patients continued systemic chemotherapy after vaccine or at progression. Results: Twenty three patient with glioblastoma received therapy including 8 with newly diagnosed disease (35%) and 15 with recurrent disease (65%) were evaluable. Immune response data is available for 20/23 patients although survival data is present for all. One grade 3 SAE of fever and chills was noted otherwise therapy was well tolerated. Within the newly diagnosed GBM cohort the median overall survival (OS) was 25.5 months (15,31+), and within the recurrent GBM cohort, the median OS was 16 months (8,23+). Among the recurrent GBM an increase of >1.5 X baseline interferon gamma production post vaccination was associated with a prolonged median OS 22 months (8,40) in 4/12 patients versus 17 months (9,27) in 8/12 patients. Conclusions: We were able to generate an immune response in 25% of patients which is lower than what we have seen in previous trials and suggests a limited synergy with local control. However, within the recurrent GBM cohort we did find prolonged survival in both groups with an increased survival noted in immune responders demonstrating the potential for this therapy.
The incidence of autism spectrum disorders (ASD) and attention deficit hyperactivity disorder (AD... more The incidence of autism spectrum disorders (ASD) and attention deficit hyperactivity disorder (ADHD), which frequently co-occur, are both rising. The causes of ASD and ADHD remain elusive, even as both appear to involve perturbation of the gut-brain-immune axis. CD103 is an integrin and E-cadherin receptor most prominently expressed on CD8 T cells that reside in gut, brain, and other tissues. CD103 deficiency is well-known to impair gut immunity and resident T cell function, but it's impact on neurodevelopmental disorders has not been examined. We show here that CD8 T cells influence neural progenitor cell function, and that CD103 modulates this impact both directly and potentially by controlling CD8 levels in brain. CD103 knockout (CD103KO) mice exhibited a variety of behavioral abnormalities, including superior cognitive performance coupled with repetitive behavior, aversion to novelty and social impairment in females, with hyperactivity with delayed learning in males. Brain protein markers in female and male CD103KOs coincided with known aspects of ASD and ADHD in humans, respectively. Surprisingly, CD103 deficiency also decreased age-related cognitive decline in both sexes, albeit by distinct means. Together, our findings reveal a novel role for CD103 in brain developmental function, and identify it as a unique factor linking ASD and ADHD etiology. Our data also introduce a new animal model of combined ASD and ADHD with associated cognitive benefits, and reveal potential therapeutic targets for these disorders and age-related cognitive decline.
2087 Background: This study evaluated the safety and immune responses to an autologous dendritic ... more 2087 Background: This study evaluated the safety and immune responses to an autologous dendritic cell vaccine pulsed with class I peptides from tumor associated antigens (TAA) expressed on gliomas and overexpressed in their cancer stem cell population (ICT-107). These TAA epitodes AIM-2. TRP-2, HER2 and AIM-2, are also overexpressed on glioblastoma multiforme (GBM) cancer stem cells. Methods: TAA epitopes included HER2, TRP-2, gp100, MAGE-1, IL13Rα2, and AIM-2. HLA-A1 and/or HLA-A2 positive glioblastoma (GBM) patients with gross total resection were eligible. Mononuclear cells from leukapheresis were differentiated into dendritic cells, pulsed with TAA peptides, and administered intradermally three times at two-week intervals in the axilla region after a standard treatment with concurrent temozolomide (TMZ) and radiation therapy for newly diagnosed (ND-GBM). Results: Twenty-one patients were enrolled with 17 ND-GBM and three recurrent GBM patients and one brainstem glioma. Immune re...
Surgery of benign intradural extra-axial tumors in- volving the clivus and craniospinal region is... more Surgery of benign intradural extra-axial tumors in- volving the clivus and craniospinal region is extremely demanding due to the close relationships between these tumors and vital neurovascular structures and to their frequent extension to adjacent areas. These factors call for surgical approaches that are wide enough to gain access to multiple contiguous topographic regions, multiangled to vary the surgical angle to different parts of the tumor, and that allow full control of neurovascular structures while minimizing the amount of brain retraction. In this milieu 193
IL-23 is a recently discovered cytokine consisting of a heterodimer of the IL-12 p40 subunit and ... more IL-23 is a recently discovered cytokine consisting of a heterodimer of the IL-12 p40 subunit and a novel 19-kDa protein, termed p19. IL-23 preferentially induces proliferation of, and IFN-γ production by, memory T cells. In the present study, we transduced freshly cultured dendritic cells (DC) with an adenoviral vector carrying the single-chain IL-23 cDNA. Message RNA and protein expression of IL-23 from the transduced DC were detected by RT-PCR and ELISA respectively. Intratumoral implanting IL-23 expressing DC into intracranial GL-26 glioma bearing C57bl/6 mice resulted in prolonged survival compared with the control mice, which were intracranial bearing GL-26 glioma implanted with empty vector transduced DC. Enhanced CD8 + T cells infiltration within the tumors were detected by immunohistochemistry in brain sections from the mice treated by IL-23 expression DC. Cytotoxic T lymphocyte (CTL) assay of the spleen cells from the IL-23 expressing DC treated mice shown that CTL activities against GL-26 glioma but not irrelevant tumors were augmented. In addition, the mice survived intracranial glioma by IL-23 expressing DC treatment were resistant to intracranial rechallenge with the same GL-26 cell line. This tumor-specific protective immunity was associated with enhanced IFN-γ expression in the brain. Furthermore, the antitumor activities of IL-23 expressing DC was also observed in athymic nude mice but greatly impaired compared with that in C57bl/6 mice. Natural killer cells depletion for the athymic nude mice abolished the antitumor function. Taken together, these data suggest that DC as powerful antigen presenting cells can elicit tumor-specific antitumor immune responses after transduced by IL-23. T cells are crucial for the antitumor activity of the IL-23 expressing DC and natural killer cells are also involved in the process.
Object. An approach toward the treatment of intracranial gliomas was developed in a rat experimen... more Object. An approach toward the treatment of intracranial gliomas was developed in a rat experimental model. The authors investigated the ability of “professional” antigen-presenting cells (dendritic cells) to enhance host antitumor immune responses when injected as a vaccine into tumor-bearing animals.Methods. Dendritic cells, the most potent antigen-presenting cells in the body, were isolated from rat bone marrow precursors stimulated in vitro with granulocyte—macrophage colony-stimulating factor (GM-CSF) and interleukin-4. Cultured cell populations were confirmed to be functional antigen-presenting cells on the basis of expressed major histocompatibility molecules, as analyzed by fluorescence-activated cell sorter cytofluorography. These dendritic cells were then pulsed (cocultured) ex vivo with acid-eluted tumor antigens from 9L glioma cells. Thirty-eight adult female Fischer 344 rats harboring 7-day-old intracranial 9L tumors were treated with three weekly subcutaneous injection...
Immune-based therapy confers limited benefits to hosts bearing late-stage tumors. Mounting eviden... more Immune-based therapy confers limited benefits to hosts bearing late-stage tumors. Mounting evidence points to local suppression of T cell function as the most substantial barrier to effective antitumor immunity in hosts with large tumor burdens. Despite this, events responsible for locally defective T cells and immune suppression in tumors remain unclear. We describe in this study a predominant T cell population localized within two murine tumors that is characterized by expression of apoptotic markers and TCRαβ/CD3, but not CD4, CD8, or NK-associated markers. These defective cells resembled double negative (DN) T cells in lpr mice, harbored defects in the expression of T cell signaling molecules, and produced the anti-inflammatory cytokine, IL-10. Conditions known to increase or decrease the accumulation of lpr DN T cells had corresponding effects on local DN tumor infiltrating lymphocyte (TIL) levels and inversely impacted host survival. Adoptive transfer into s.c. tumors demonstr...
For unknown reasons, advanced age remains a dominant predictor of poor clinical outcome for nearl... more For unknown reasons, advanced age remains a dominant predictor of poor clinical outcome for nearly all cancers. A decrease in the production of T cells by the thymus accompanies normal aging and parallels the age-dependent increase in cancer progression, but the specific impact of immunity on tumor progression in general is unknown. Glioblastoma multiforme (GBM), the most common primary brain neoplasm, is characterized by rapid age-dependent rates of progression and death. In this study, we show levels of CD8+ recent thymic emigrants (RTEs) accounted for the prognostic power of age on clinical outcome in GBM patients. CD8+ RTEs, typically a tiny proportion of CD8+ T cells, remarkably accounted for the majority of tumor Ag-binding small precursor cells in PBMC from these patients and from healthy individuals. Large blasting tumor Ag-binding cells comprised of CD8+ RTEs and phenotypically related cells were predominantly expanded following experimental vaccination of GBM patients. Qua...
Cancer vaccine trials have failed to yield robust immune-correlated clinical improvements as obse... more Cancer vaccine trials have failed to yield robust immune-correlated clinical improvements as observed in animal models, fueling controversy over the utility of human cancer vaccines. Therapeutic vaccination represents an intriguing additional therapy for glioblastoma multiforme (GBM; grade 4 glioma), which has a dismal prognosis and treatment response, but only early phase I vaccine trial results have been reported. Immune and clinical responses from a phase II GBM vaccine trial are reported here. IFN-γ responsiveness was quantified in peripheral blood of 32 GBM patients given therapeutic dendritic cell vaccines. Posttreatment times to tumor progression (TTP) and survival (TTS) were compared in vaccine responders and nonresponders and were correlated with immune response magnitudes. GBM patients (53%) exhibited ≥1.5-fold vaccine-enhanced cytokine responses. Endogenous antitumor responses of similar magnitude occurred in 22% of GBM patients before vaccination. Vaccine responders exhi...
Background This study evaluated the safety and immune responses to an autologous dendritic cell v... more Background This study evaluated the safety and immune responses to an autologous dendritic cell vaccine pulsed with class I peptides from tumor-associated antigens (TAA) expressed on gliomas and overexpressed in their cancer stem cell population (ICT-107). Methods TAA epitopes included HER2, TRP-2, gp100, MAGE-1, IL13Ra2, and AIM-2. HLA-A1-and/or HLA-A2positive patients with glioblastoma (GBM) were eligible. Mononuclear cells from leukapheresis were differentiated into dendritic cells, pulsed with TAA peptides, and administered intradermally three times at two-week intervals. Results Twenty-one patients were enrolled with 17 newly diagnosed (ND-GBM) and three recurrent GBM patients and one brainstem glioma. Immune response data on 15 newly diagnosed patients showed 33 % responders. TAA expression by qRT-PCR from fresh-frozen tumor samples showed all patient tumors expressed at least three TAA, with 75 % expressing all six. Correlations of increased PFS and OS with quantitative expression of MAGE1 and AIM-2 were observed, and a trend for longer survival was observed with gp100 and HER2 antigens. Target antigens gp100, HER1, and IL13Ra2 were downregulated in recurrent tumors from 4 HLA-A2? patients. A decrease in or absence of CD133 expression was seen in five patients who underwent a second resection. At a median follow-up of 40.1 months, six of 16 ND-GBM patients showed no evidence of tumor recurrence. Median PFS in newly diagnosed patients was 16.9 months, and median OS was 38.4 months. Conclusions Expression of four ICT-107 targeted antigens in the pre-vaccine tumors correlated with prolonged overall survival and PFS in ND-GBM patients. The goal of targeting tumor antigens highly expressed on glioblastoma cancer stem cells is supported by the observation of decreased or absent CD133 expression in the recurrent areas of gadolinium-enhanced tumors.
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Papers by Keith Black