Papers by Alberto Horenstein
Journal of Immunological Methods, Apr 1, 2003
Murine monoclonal antibodies (mAb) from cell culture supernatants have been purified in order to ... more Murine monoclonal antibodies (mAb) from cell culture supernatants have been purified in order to acquire clinical grade for in vivo cancer treatment. The starting material was purified by high performance liquid chromatography (HPLC) systems ranging from the analytical scale process to a scaleup to 1 g per batch. Three columns (Protein A affinity chromatography with single-step elution, hydroxyapatite (HA) chromatography followed by linear gradient elution and endotoxin removing-gel chromatography), exploiting different properties of the mAb were applied. The final batches of antibody were subjected to a large panel of tests for the purpose of evaluating the efficacy of the downstream processing.
Biotechnology Advances, Aug 31, 2000
This survey is an overview of the applications of murine, humanized and recombinant monoclonal an... more This survey is an overview of the applications of murine, humanized and recombinant monoclonal antibodies for in vivo diagnostic and therapeutic applications. Monoclonal antibodies (mAb) have been applied to the diagnosis and therapy of an array of human diseases. The initial failures of early clinical trials have been overcome through the production of a new generation of mAb which features reduced immunogenicity and improved targeting abilities. The early models of mAb therapy were focused on enhancing the cytolytic mechanisms against the tumor cells. More recently, successful mAb-based therapies were targeted to molecules involved in the regulation of growth of cancer cells. This has highlighted the relevance of understanding receptor-mediated signaling events, and may provide new opportunities for anti-tumor antibody targeting. Despite all the difficulties, clinical data is outlining an increasingly significant role for antibody-mediated cancer therapy as a versatile and powerful instrument in cancer treatment. One reasonable expectation is that treatment at an earlier stage in the disease process or in minimal residual disease may be more advantageous.
LH and human chorionic gonadotropin (hCG) control steroid production and gametogenesis. They also... more LH and human chorionic gonadotropin (hCG) control steroid production and gametogenesis. They also function as growth factors through interaction with a specific receptor that is a member of the seven-transmembrane receptor family coupled via G proteins to signal pathways involving cAMP and phos- pholipase C/inositol 3 phosphate. For this study, monoclonal antibodies (mAbs) were raised against the human LH receptor
Journal of biological regulators and homeostatic agents
Research communications in chemical pathology and pharmacology
Capping was studied in lymphocytes obtained from controls and patients with Duchenne muscular dys... more Capping was studied in lymphocytes obtained from controls and patients with Duchenne muscular dystrophy. Before the induction of capping by anti-Ig antibodies the cells were incubated with increasing concentrations of calcium and lanthanum. It was found that the presence or absence of extracellular calcium had no effect. Lanthanum, which blocks active calcium extrusion, altered the proportion of capping in both controls and Duchenne lymphocytes. These observations are discussed in relation to the possible involvement of free intracellular calcium in normal controls and patients with Duchenne muscular dystrophy.
The Journal of Immunology
Human CD38, a pleiotropic molecule with ADP-ribosyl cyclase activity, regulates activation and gr... more Human CD38, a pleiotropic molecule with ADP-ribosyl cyclase activity, regulates activation and growth of several cell types. Its in vivo function is incompletely determined, mainly due to the lack of evidence concerning the existence of a single or multiple ligands. We recently observed that CD38 rules a selectin-type adhesion between lymphoid cells and HUVECs. A panel of murine mAbs raised against HUVEC included one (Moon-1) constantly blocking the CD38-mediated adhesion of several cell lines to HUVEC. Tissue distribution studies and an extended immunohistochemical analysis on the majority of normal human tissues revealed that the Moon-1 molecule displays a unique pattern of expression, being present at high levels on resting and activated vascular endothelium, on the majority of monocytes, platelets, NK cells, and to a lesser extent on T, B, and myeloid cells. The Moon-1 structure of an apparent molecular mass of 120 kDa proved to be a ligand for human CD38, as inferred by the direct binding observed when using a chimeric mouseCD8a-humanCD38 (mCD8cu-hCD38) molecule as a probe in Western blot experiments. Furthermore, Ab-induced modulation experiments highlighted an association between the Moon-1 molecule and human CD38 on the surface of cell lines coexpressing the two structures, which also share a common regulation system of surface expression. Finally, direct ligation of Moon-1 on T cell lines caused a relevant increase in the cytoplasmic concentration of calcium ([Ca2+l,).
Cation Flux Across Biomembranes, 1979
Journal of nuclear biology and medicine (Turin, Italy: 1991)
a suitable whole antibody or its fragments can be success fully used to localize specific antigen... more a suitable whole antibody or its fragments can be success fully used to localize specific antigen sites in vivo, most notably from thrombotic, infectious, inflammatory or can cerous lesions (2â€"4).
Cells, 2015
Nicotinamide adenine dinucleotide (NAD + ) is an essential co-enzyme reported to operate both int... more Nicotinamide adenine dinucleotide (NAD + ) is an essential co-enzyme reported to operate both intra-and extracellularly. In the extracellular space, NAD + can elicit signals by binding purinergic P2 receptors or it can serve as the substrate for a chain of
Enzyme
The protein kinase activity of a 10,000 g supernatant of purified human lymphocytes can be resolv... more The protein kinase activity of a 10,000 g supernatant of purified human lymphocytes can be resolved by DEAE-cellulose chromatography into six protein kinase fractions: three of them phosphorylate casein preferentially, and three histones. The same procedure with the corresponding nuclear fraction yields only two casein kinases. All these fractions, except one casein kinase of the cytosol, have been studied with respect to protein and nucleotide specificity, effect of salts and of cyclic nucleotides, sedimentation, etc. The results obtained indicate that the enzyme fractions of the cytosol have distinct characteristics, suggesting that they are different protein kinases, and that the nuclear kinases are similar to the two main casein kinases of the cytosol.
Journal of leukocyte biology, Jan 18, 2015
BPZE1 is a live attenuated pertussis vaccine that successfully completed a phase 1 safety trial. ... more BPZE1 is a live attenuated pertussis vaccine that successfully completed a phase 1 safety trial. This article describes the induction of unconventional suppressor T cells-producing ADO by MDDCs exposed to BPZE1 (BPZE1-DC) through distinct ectoenzymatic pathways that limit the damaging effect of inflammation. BPZE1-DC induces CD4(+) and CD8(+) T lymphocytes to express 2 sets of ectoenzymes generating ADO: 1 set is part of the conventional CD39/CD73 pathway, which uses ATP as substrate, whereas the other is part of the CD38/CD203a/CD73 pathway and metabolizes NAD(+). The contribution of the ADO-generating ectoenzymes in the regulatory response was shown by: 1) selective inhibition of the enzymatic activities of CD39, CD73, and CD38; 2) the ability of suppressor T cells to convert exogenously added ATP and NAD(+) to ADO; and 3) a positive correlation between ectoenzyme expression, ADO levels, and suppression abilities. Thus, T lymphocytes activated by BPZE1-DC shift to a suppressor sta...
Journal of biological regulators and homeostatic agents
Oncotarget, Jan 25, 2015
Nucleotide-metabolizing ectoenzymes are endowed with an extracellular catalytic domain, which is ... more Nucleotide-metabolizing ectoenzymes are endowed with an extracellular catalytic domain, which is involved in regulating the extracellular nucleotide/nucleoside balance. The tumor microenvironment contains high levels of adenosine (ADO) generated by this enzymatic network, thus promoting tumor growth by inhibiting anti-tumor immune responses. ADO inhibition in melanoma murine models limits tumor metastases and restores anti-tumor immune responses.This work investigates the expression and function of ectoenzymes in primary human melanoma cell lines. All of latter cells expressed CD38, CD39, CD73, and CD203a/PC-1, and produced ADO from AMP and NAD+. Melanoma cells inhibited T cell proliferation through an ADO-dependent mechanism, since such inhibition was reverted using CD38/CD73 specific inhibitors.Melanoma cells abolished the function of effector memory, central memory and reduced naïve CD4+ T cell proliferation. Accordingly, phosphorylation of S6 ribosomal protein, p38 and Stat1 was...
Journal of immunology (Baltimore, Md. : 1950), Jan 19, 2015
Recent studies suggested that human CD56(bright)CD16(-) NK cells may play a role in the regulatio... more Recent studies suggested that human CD56(bright)CD16(-) NK cells may play a role in the regulation of the immune response. Since the mechanism(s) involved have not yet been elucidated, in the present study we have investigated the role of nucleotide-metabolizing enzymes that regulate the extracellular balance of nucleotides/nucleosides and produce the immunosuppressive molecule adenosine (ADO). Peripheral blood CD56(dim)CD16(+) and CD56(bright)CD16(-) NK cells expressed similar levels of CD38. CD39, CD73, and CD157 expression was higher in CD56(bright)CD16(-) than in CD56(dim)CD16(+) NK cells. CD57 was mostly expressed by CD56(dim)CD16(+) NK cells. CD203a/PC-1 expression was restricted to CD56(bright)CD16(-) NK cells. CD56(bright)CD16(-) NK cells produce ADO and inhibit autologous CD4(+) T cell proliferation. Such inhibition was 1) reverted pretreating CD56(bright)CD16(-) NK cells with a CD38 inhibitor and 2) increased pretreating CD56(bright)CD16(-) NK cells with a nucleoside trans...
A CD38/CD203a/CD73 ectoenzymatic pathway independent of CD39 drives a novel adenosinergic loop in... more A CD38/CD203a/CD73 ectoenzymatic pathway independent of CD39 drives a novel adenosinergic loop in human T lymphocytes. Horenstein AL, Chillemi A, Zaccarello G, Bruzzone S, Quarona V, Zito A, Serra S, Malavasi F. Oncoimmunology. 2013 Sep 1;2(9):e26246. Epub 2013 Sep 26. PMID: 24319640 [PubMed]
Blood, 1998
During development, mice with mutations of stem cell factor (SCF) or its receptor c-kit exhibit d... more During development, mice with mutations of stem cell factor (SCF) or its receptor c-kit exhibit defects in melanogenesis, as well as hematopoiesis and gonadogenesis. Consequently, accumulating evidence suggests that the c-kit/SCF system plays a crucial role in all of these processes and in tumors which derive from them. Especially in neuroblastoma (infant tumors of neuroectoderm crest derivation such as melanocytes) it would appear that an autocrine loop exists between c-kit and SCF, and that the functional block of the c-kit receptors with monoclonal antibodies (MoAbs) results in a significant decrease in cellular proliferation. We studied the expression and role of c-kit and SCF in cell lines of soft tissue sarcoma of neuroectodermic origin, such as Ewing's sarcoma (ES) and peripheral neuro-ectodermal tumors (PNET). Using flow cytometry with MoAb CD117 PE, c-kit expression was highlighted in all six of the cell lines examined. This receptor was specifically and functionally ac...
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Papers by Alberto Horenstein