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Scandinavian Journal of Immunology | 1986

Early Defect of Phagocytic Cell Function in Subjects at Risk for Acquired Immunodeficiency Syndrome

M. E Estevez; Isidro J. Ballart; Diez Ra; N. Planes; C. Scaglione; Luisa Sen

We studied the functions of peripheral blood monocytes and polymorphonuclear cells in 15 apparently healthy homosexual men, eight homosexual or bisexual subjects with unexplained generalized lymphadenopathies (pre‐AIDS), four homosexual men with acquired immunodeficiency syndrome (AIDS), and 15 heterosexual men. In comparison with normal controls, the homosexual groups studied presented a decreased monocyte candidacidal activity for Candida pseudotropicalis that gradually deteriorates as the clinical symptoms progress towards AIDS. The monocyte phagocytic function was retained. Although the phagocytic and candidacidal activities of the polymorphonuclear cells did not differ from those of the normal controls, the candidacidal activity in some of the cases studied was unusually enhanced, indicating that the cells were in an activated state. In addition, only two of nine sera tested from asymptomatic homosexual males were positive for antibodies to HTLV‐III/LAV, while six out of eight pre‐AIDS and both of the two AIDS patients tested had antibodies to AIDS‐associated retrovirus. We suggest that in AIDS the phagocytic system is already involved, together with B and T lymphocyte abnormalities, during the early events of the syndrome, even without the detection of AIDS‐associated retrovirus antibodies.


Microbiology and Immunology | 1991

Lymphocyte Subpopulations and Cytokine Production in Paracoccidioidomycosis Patients

A. Javier Bava; Alicia Mistchenko; M. Fernanda Palacios; M. E Estevez; Nora I. Tiraboschi; Luisa Sen; Ricardo Negroni; Diez Ra

Despite the postulated role of the immune system in the control of the infection by Paracoccidioides brasiliensis, only a few studies have addressed this point in patients. The determination of total lymphocytes and their subpopulations in 6 untreated patients with the chronic form of paracoccidiodomycosis showed that half of them were lymphopenic, because of low number of CD4+ T‐lymphocytes. All patients had low CD4/CD8 ratios. On the contrary, B‐lymphocytes were normal in all patients. An additional patient, studied on treatment with ketoconazole, had normal lymphocyte counts in all subpopulations, as did one of the patients previously studied at diagnosis when he received specific antimycotic treatment. The production of interferon and tumor necrosis factor, determined by bioassay in supernatants of mononuclear blood cells of the patients, induced by interleukin 2 in vitro was significantly lower than that of normal subjects. These results show that patients with paracoccidioidomycosis have a defect in blood lymphocyte subsets as well as in the ability to produce regulatory cytokines.


Journal of Pediatric Hematology Oncology | 2003

Serum levels of interleukin-1 receptor antagonist and tumor necrosis factor-alpha are elevated in children with Langerhans cell histiocytosis.

Diego Rosso; Mario Ripoli; Adriana Roy; Diez Ra; Marta Zelazko; Jorge Braier

Purpose Langerhans cell histiocytosis (LCH) is a rare disease with variable prognosis in which lesions and clinical features suggest that pro- and anti-inflammatory cytokines may be involved in its pathogenesis. The authors wished to evaluate whether serum levels of interleukin-1 receptor agonist (IL-1Ra) and tumor necrosis factor-alpha (TNF-&agr;) are elevated in children with LCH and decrease after chemotherapy. Patients and Methods Circulating levels of IL-1Ra and TNF-&agr; were measured in 23 and 8 children with LCH, respectively, and 7 pediatric controls using commercially available ELISA kits. All patients fulfilled the Histiocyte Society LCH Protocols criteria for diagnosis, stratification, and treatment. Results Pretreatment concentrations of IL-1Ra and TNF-&agr; were found to be significantly elevated in patients with LCH compared with controls. Among LCH substages, a significant difference in IL-1Ra values was observed between individuals with single-system single-site disease vs. multisystem disease with risk-organ dysfunction. In all eight patients evaluated, IL-1Ra levels decreased after 6 weeks of chemotherapy. Lower values of TNF were observed in three patients after treatment. A positive and significant correlation between IL-1Ra and TNF serum concentrations was found. Conclusions Patients with LCH have elevated levels of IL-1Ra and TNF, which decrease after chemotherapy.


Journal of Immunological Methods | 1987

Comparison of Candida killing activity measured by chemiluminescence and cytomorphological methods in human phagocytes

Isidro J. Ballart; M. E Estevez; Diez Ra; Luisa Sen

Phagocyte function can be assayed by many laboratory tests including a cytomorphological method that uses Candida cells as target. The aim of this study was to correlate this technique with the production of toxic oxygen metabolites, measured by chemiluminescence (CL). The biological function of polymorphonuclear (PMN) cells and monocytes from the blood of 24 normal subjects and 25 patients with immunodeficiency diseases were studied. CL was measured using opsonized zymosan as the stimulating agent and, for the evaluation of Candida killing activity, C. pseudotropicalis and C. albicans were used as targets. A linear correlation between CL and lytic activity was observed with both PMN and monocytes from normal subjects and patients (r = 0.563 to 0.955; P less than 0.05 to less than 0.001). Our results indicate that the production of toxic oxygen metabolites, as measured by CL is closely related to the killing of Candida by PMN and monocytes.


International Journal of Immunopharmacology | 1994

Growth hormone inhibits normal B-cell differentiation and neutrophils' chemotaxis in vitro.

M. Cecilia Fornari; Mariano Scolnik; M. Fernanda Palacios; Alberto D. Intebi; Diez Ra

In acromegalic patients we have previously described a low ability of B-lymphocytes to differentiate into plasma cells under PWM stimulation, and a decreased chemotaxis of polymorphonuclear leukocytes (PMN) towards N-formylmethionylphenilalanine (FMP). In this study we examined the effect of exogenous GH over these immune functions in normal cells. PMN were purified by dextran sedimentation, incubated with recombinant human GH (0 to 20 ng/ml) and subjected to stimulation with FMP. PBMC were cultured with or without PWM, in the presence of GH (between 0 and 100 ng/ml). Plasma cells were determined as hemolysis plaque forming cells and also by immunofluorescence. GH, in a dose-dependent way, decreased directed migration of PMN (5 ng/ml: 1.787 +/- 148 microns; 10 ng/ml: 1.581 +/- 221 microns; 20 ng/ml: 1.569 +/- 149 microns, all as mean +/- S.E.M.), when compared to similar values of untreated PMN (0 ng/ml 2.085 +/- 139 microns). GH treatment did not modify spontaneous migration. Net migration showed the same pattern as directed migration. GH decreased dose-dependently the PWM-driven differentiation of B-lymphocytes into plasma cells to 60% of the basal level. Although not significantly, GH tended to increase spontaneous B-cell differentiation. These results could account for the already described defect in B-cell differentiation and PWN chemotaxis in acromegaly, emphasizing the relationship between the endocrine and immune systems.


Scandinavian Journal of Immunology | 1993

Impaired Phagolysosomal Fusion of Peripheral Blood Monocytes from HIV‐Infected Subjects

M. G. Pittis; G. Sternik; Luisa Sen; Diez Ra; N. Planes; D. Pirola; M. E Estevez

We evaluated phagolysosomal fusion in peripheral blood monocytes from 20 HIV‐infected individuals and 40 normal controls, using a fluorescence assay with acridine orange as marker. The percentages of phagolysosomal fusion of monocytes from HIV‐infected subjects, after 30 and 60 min of yeast ingestion, (mean ± standard deviation) 57·2 ± 17 and 63·2 ± 18·6, respectively, when compared to normal controls (72·4 ± 7·8 and 77 ± 8·1), did not differ significantly. However, there was a direct linear association between the percentages of phagolysosomal fusion and CD4+ lymphocytes (P<0·001) or CD4/CD8 T‐cell ratio (P<0·01). These results suggest that phagolysosomal dysfunction becomes evident at late stages of HIV infection and progresses as CD4+ T‐lymphocyte count and CD4/CD8 T‐cell ratio decrease. On the other hand, recombinant gp120 inhibited significantly normal phagolysosomal fusion at concentrations ranging between 1 and 1000 ng/ml. Taking together the results obtained, we can conclude that gp120 could be responsible for monocyte phagolysosomal dysfunction observed in HIV infected patients.


Transfusion and Apheresis Science | 2009

Utilization study of filgrastim (Neutromax®) during autologous haematopoietic precursor transplantation for myeloma and lymphoma patients

Hugo H. Ferro; Mariana Juni; Ricardo Bello; Alejandro Vidal; Diez Ra; Santiago Pavlovsky

To describe utilization of a biosimilar product containing filgrastim (Neutromax), data of 414 myeloma or lymphoma patients subjected to autologous SCT between 1998 and 2007 were analyzed. Filgrastim was used for mobilization of progenitors (5 days at 300 microg/day) and for the recovery of neutropenia after transplantation (100 microg/day, since day +5). In 2003, the excipient mannitol was replaced by sorbitol. A mean dose of 9.47 x 10(6)CD34(+)cells/kg was infused; 100 neutrophils/mm(3) required 5-day treatment; 500 neutrophils/mm(3), 6 days and 1000 neutrophils/mm(3), 7 days. Neutromax effect in SCT is similar to reports with other brands. No difference was found between formulations.


Scandinavian Journal of Immunology | 1995

Natural Killer Suppressor Factors in Sera from HIV‐Infected Subjects

M. A. Goicoa; Luisa Sen; P. S. Iannitelli; Diez Ra; M. E Estevez

We investigated the presence of NK suppressor factors in HIV+ sera. We further investigated if gp120 could be one of the substances responsible for the impairment of NKC regulation found in HIV+ asymptomatic patients. Our results indicate that HIV+ sera inhibit significantly normal NKC in a dose‐dependent way, even at concentrations as low as 1%. The inhibitory effect of HIV+ sera decreased, but was not completely removed, by adsorptions of IgG or by treatment with a MoAb against human FcIgG. Pretreatment of normal effector cells with anti‐CD 16 MoAb slightly reduced their cytotoxic capability, but did not modify the suppressor effect of HIV+ sera. The preincubation of normal PBMC with recombinant gp120 had also a suppressor effect even at 10ng/ml. Pretreatment of HIV+ sera with anti‐gp120 or anti‐FcIgG MoAb reduced, but not completely, their inhibitory effect. In conclusion, HIV+ serum has a dose‐dependent inhibitory effect on normal NKC. Most of this inhibition is caused by IgG, but other substances, such as gp120, can also contribute to it. Since the removal of IgG and further treatments of HIV+ sera were not able to abrogate completely the NK suppression, other serum factors still undetermined (TNF‐α, other cytokines), should be considered.


Immunology Letters | 2001

In vivo effect of snake phospholipase A2 (crotoxin+cardiotoxin) on serum IL-1α, TNF-α and IL-1ra level in humans

Luis A. Costa; M. Cecilia Fornari; Vanina E. Berardi; Horacio Miles; Diez Ra

Abstract VRCTC-310-Onco (crotoxin, a secretory phospholipase A 2 +cardiotoxin) is under development as an anti-neoplastic agent. Pro-inflammatory cytokines TNF-α and interleukin 1 α (IL-1α) and anti-inflammatory cytokine IL-1 receptor antagonist (IL-1ra) were measured with commercial ELISA kits in sera corresponding to 23 cycles with doses between 0.0025 and 0.023 μg/kg body weight, obtained during the phase I trial of VRCTC-310-Onco. Neither serum TNF-α nor IL-1α did change significantly after VRCTC-310-Onco. Basal IL-1ra was 794±97 pg/ml, by 3 h it was similar, 651±99 pg/ml and at 24 h p.i. it increased to 1197±122 pg/ml ( P


Drug Research | 2011

Bio equivalence of Two Subcutaneous Pharmaceutical Products of Interferon Beta la

Guillermo Di Girolamo; Marcelo Andrés Kauffman; E Gonzalez; Mariana Papouchado; Alejandra Ramirez; Guillermo Keller; Cesar Horacio Carbonetto; Susana Dabsys; Alejandro Vidal; Aı́da E. Sterin-Prync; Diez Ra

Blastoferon, in the following referred to as the test product, is a pharmaceutical product of interferon beta la (CAS 220581-49-7) currently marketed as a biosimilar to the innovator Interferon beta la product (referred to as the reference product). Pharmacokinetics and pharmacodynamIcs assays are critically relevant to demonstrate similarity between biopharmaceuticals. The aims of the present study were to investigate the bioavailability (BA) of the test product (either absolute or relative to the innovator product) and to compare the extent of increase of neopterin concentration following administration of either product. Two studies were performed: initially, an absolute BA assay with i.v. and s.c. injection of test product to 12 healthy subjects. Second, a formal relative BA study with s.c. injections of 88 microg of both products to 24 healthy volunteers. Blood samples for pharmacokinetic and pharmacodynamic profiling were drawn at different intervals after injection. Interferon beta (IFNB) concentrations were determined by ELISA. In the absolute BA study, a single s.c. dose of 44 microg of the test product resulted in a median bioavailable fraction of 29%, a median T(max) of 4 h (4-6) and a C(max) of 3.69 (3.27-4.41) IU x ml(-1). In the relative BA study, values for the test product were: median T(max) of 3 h (2-18), C(max) of 5.39 (4.99-6.31) IU x ml(-1), AUC (0-72) of 142.86 (134.16-190.15) IU x h x ml(-1) and AUC(0-infinity) of 190.95 (174.23-303.13) IU x h x ml(-1). The corresponding values for the innovator product were: T(max) of 3 h (1-24), C(max) of 4.44 (4.12-5.40) IU x ml(-1), AUC(0-72) of 128.77 (121.18-170.92) IU x h x ml(-1) and AUC(0-affinity) of 192.61 (183.04-286.46) IU x h x ml(-1). The AUC(0-72) ratio was 111% (CI 90%: 106-116), the AUC(0-affinity) was 99% (CI 90%: 92-107) and the C(max) ratio was 121% (CI 90%: 112-131). IFNB1a increased neopterin levels in both studies. Both products induced side-effects commonly reported for IFN with no serious adverse events. This study presents pharmacokinetics parameters of the test product and demonstrates similar bioavailability of IFNB1a for both pharmaceutical products.

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M. E Estevez

Academia Nacional de Medicina

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Luisa Sen

Academia Nacional de Medicina

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Isidro J. Ballart

Academia Nacional de Medicina

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Luisa Sen

Academia Nacional de Medicina

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M. Cecilia Fornari

Academia Nacional de Medicina

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M. Fernanda Palacios

Academia Nacional de Medicina

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A. Javier Bava

Academia Nacional de Medicina

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N. Planes

Academia Nacional de Medicina

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Ricardo Negroni

University of Buenos Aires

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