Maternal schistosomiasis: IL-2, IL-10 and regulatory T lymphocytes to unrelated antigen in adult offspring mice

Abstract INTRODUCTION: We evaluated IL-10, IL-2 and regulatory T cells (Treg), in response to ovalbumin (OA), in offspring from schistosomotic mouse mothers. METHODS: We used animals born (BIM) or suckled (SIM) from infected mothers; and mice born/suckled from infected (BSIM) or non-infected mothers (CONTROL). After OA+adjuvant immunization, spleen cells were cultured, with or without OA, and doubly marked for cytometry. RESULTS: BIM showed fewer CD4+/IL-2+ and more B220+/IL-10+ cells, whereas the SIM group showed increased Treg frequency. BSIM had fewer B220+/IL-10+ and Treg cells. CONCLUSIONS: Separately, gestation or nursing induced immunosuppressive cells in infected mothers, but improved anti-OA immunity when combined.

Homing of radiolabelled recombinant interleukin-2 activated natural killer cells and their efficacy in adoptive immunotherapy against murine fibrosarcoma.

Natural killer (NK) cells are spontaneously cytotoxic against tumour target cells. Their number was found to be four times more in the spleen of tumour-bearing Swiss albino mice. After activation with recombinant interleukin-2 (rIL-2), NK cells were tested and found to seek out the tumour site when injected intravenously in tumour-bearing mice. Their potential for fighting tumours in vivo was further seen following adoptive transfer of rIL-2 activated NK (A-NK) cells in tumour-bearing mice. After surgical removal of tumour load, adoptive transfer of A-NK cells inhibited tumour recurrence in 92.3%cases, thereby suggesting the use of this protocol for therapeutic purposes to obtain a better outcome.

IL-2 Pathway Blocking in Combination with Anti-CD154 Synergistically Establishes Mixed Macrochimerism with Limited Dose of Bone Marrow Cells and Prolongs Skin Graft Survival in Mice

To facilitate the establishment of mixed chimerism with limited dose of bone marrow (BM) cells, and to achieve tolerance in skin graft model, combined blocking of costimulatory pathway and IL-2 pathway was used in minimally myeloablative model using busulfan. BM cells (2.5 x 10(7)) of BALB/c were injected into C57BL/6 mice at day 0 with full thickness skin graft after single dose injection of busulfan (25 mg/kg) on day-1. Recipients were grouped and injected the anti-CD154, CTLA4-Ig, anti-IL-2R at days 0, 2, 4, and 6 according to protocol. Mixed macrochimerism were induced in groups treated with anti-CD154+anti-CTLA4-Ig, anti-CD154+anti-IL-2R, and anti-CD154+anti-CTLA4 Ig+anti-IL-2R. Three groups having chimerism enjoyed prolonged graft survival more than 6 months. Superantigen deletion study revealed deletion of alloreactive T cells in combined blockade treated groups. In graft versus host disease model using CFSE staining, CD4+ T cell and CD8+ T cell proliferation were reduced in groups treated with CTLA4-Ig or anti-IL-2R or both in combination with anti-CD154. However, anti-IL-2R was not so strong as CTLA4-Ig in terms of inhibition of T cell proliferation. In conclusion, IL-2 pathway blocking combined with anti-CD154 can establish macrochimerism with limited dose of BM transplantation and induce specific tolerance to allograft.

IL-2 Pathway Blocking in Combination with Anti-CD154 Synergistically Establishes Mixed Macrochimerism with Limited Dose of Bone Marrow Cells and Prolongs Skin Graft Survival in Mice

To facilitate the establishment of mixed chimerism with limited dose of bone marrow (BM) cells, and to achieve tolerance in skin graft model, combined blocking of costimulatory pathway and IL-2 pathway was used in minimally myeloablative model using busulfan. BM cells (2.5 x 10(7)) of BALB/c were injected into C57BL/6 mice at day 0 with full thickness skin graft after single dose injection of busulfan (25 mg/kg) on day-1. Recipients were grouped and injected the anti-CD154, CTLA4-Ig, anti-IL-2R at days 0, 2, 4, and 6 according to protocol. Mixed macrochimerism were induced in groups treated with anti-CD154+anti-CTLA4-Ig, anti-CD154+anti-IL-2R, and anti-CD154+anti-CTLA4 Ig+anti-IL-2R. Three groups having chimerism enjoyed prolonged graft survival more than 6 months. Superantigen deletion study revealed deletion of alloreactive T cells in combined blockade treated groups. In graft versus host disease model using CFSE staining, CD4+ T cell and CD8+ T cell proliferation were reduced in groups treated with CTLA4-Ig or anti-IL-2R or both in combination with anti-CD154. However, anti-IL-2R was not so strong as CTLA4-Ig in terms of inhibition of T cell proliferation. In conclusion, IL-2 pathway blocking combined with anti-CD154 can establish macrochimerism with limited dose of BM transplantation and induce specific tolerance to allograft.

Tuberculin specific T cell responses in BCG vaccinated children.

The effector mechanisms of BCG protection were examined 5-7 years after vaccination. The in vitro lymphoproliferation, following stimulation with tuberculin, in normal, (A) vaccinated and (B) unvaccinated children and children with tuberculosis (C), were assayed. The mean stimulation index (SI) of lymphocyte transformation in normal subjects were significantly (P < 0.05) higher than those with tuberculosis. The ratio of tuberculin-specific CD4 to CD8 cells in short-term cultures were significantly (P less than 0.05) higher in the vaccinees. In group (A), 70 % had positive ratios as against 20 %and 0 %in groups (B) and (C), respectively. Secretion of IL-2 by the cells was significantly (P < 0.05) high in the vaccinated. None of the unvaccinated children had positive levels of IL-2. The vaccinees also had highly significant (P < 0.01) levels of IFN-)in the supernatants of cell-cultures, following tuberculin stimulation. In majority of the BCG vaccinated children, the stimulation of specific TH1 cells seem to be considerably high, in short-term in vitro cultures. While these responses were not so marked in the unvaccinated, they were almost totally absent in the patients.

Mechanism of Immune Response During Immunotherapy

Tumor immunology embraces an extensive array of biological phenomena that include interactions between neoplastic cells and the innate and adaptive immune response. Among immune cells, T cells have taken the center stage because they can be easily demonstrated to specifically recognize autologous cancer cells. However, their role is limited and other components of the immune response are likely necessary for the completion of cancer rejection. Metastatic melanoma and renal cell carcinoma (RCC) are malignancies strongly predisposed to regress in response to the systemic administration of high-dose interleukin (IL)-2. Several clinical Studies in extensive cohorts of patients have shown that this treatment can induce complete or partial clinical regressions of metastatic disease in 15 to 20% of patients who receive this treatment.1-6 Although IL-2 has direct pluri-potent effects on cells with immune and inflammatory function, it remains unexplained which cell subset is implicated in mediating tumor regression. In a quest to characterize the mechanism of action of IL-2 during the course of immunotherapy, we have investigated the early changes in transcriptional profiles of circulating mononuclear cells and microenvironment of melanoma metastases following high dose IL-2 administration (720,000 IU/kg) by serial sampling of blood cells and tumors in the form of fine needle aspirate (FNA).7 Furthermore, studies are currently ongoing to characterize the proteomic profiling of RCC patients undergoing the same treatment using protein arrays (manuscript in preparation). The predominant activation of genes related to inflammation and activation of mononuclear phagocytes lead us to further characterize this cell subset in the context of stimulation with a panel of soluble factors potentially present in the circulation and tumor microenvironment.

proliferación linfocitaria inducida por PPD y producción de IL-2 en pacientes con tuberculosis / Annual reports 1995 / Lymphocytes proliferation induced by PPD and IL-2 production in patients with tuberculosis

El objetivo del presente estudio es evaluar la respuesta proliferativa inducida por PPD, PHA y la producción de IL-2 en pacientes con tuberculosis pulmonar activa. Se utilizaron células mononucleares de los pacientes, que fueron estimuladas con fitohemaglutinina (PHA), tuberculina (PPD) por 72 horas para estudiar la proliferación celular utilizando un método colorimétrico (MTT). En la misma forma fueron tratadas células mononucleares de adultos normales como control. Además, con el objeto de evaluar la acción de IL-2 en la proliferación celular, se adicionó IL-2 a los cultivos con PHA. Por otra parte, se extrajo sobrenadantes de los cultivos con PHA y PPD a las 24 horas para el dosaje de IL-2 por el método de ELISA. De un total de 12 pacientes con tuberculosis pulmonar activa se observó que en el 20 por ciento de los pacientes estudiados la proliferación celular inducida por PHA esta disminuida en relación a los controles normales. Con la adición de IL-2 a los cultivos con PHA no se observó un aumento en la proliferación. Con respecto a la PPD se obtuvo una respuesta menor que a la obtenida con PHA. En cuanto a la producción de IL-2 solo en el 25 por ciento de los pacientes se observaron niveles superiores de IL-2 comparados a la de los controles

Mecanismos de imunossupressäo na infecçäo aguda pelo "Trypanosoma cruzi" / Immunosuppression mechanisms in acute infection to \"Trypanosoma cruzy\"

Os autores apresentam consideraçöes gerais sobre a resposta de imunossupressao associada à moléstia de Chagas, com o objetivo de contribuir para o entendimento deste importante e promissor ramo do conhecimento.

IN vitro cell-mediated immune reactions in herpes zoster patients treated with cimetidine.

In a double-blind placebo-control study the immunomodulating effect of cimetidine treatment for one week and placebo was investigated for cell-mediated immune reactions of 22 patients with herpes zoster (HZ). The mitogen induced leukocyte migration inhibition test (LMIT) and the in vitro proliferation of the patients' lymphocytes to exogenous IL-2 were used. Before any treatment, the mitogen induced leukocyte migration inhibition capacity (LMIC) of HZ patients was found to be significantly reduced (p < 0.02) as compared to healthy blood bank donors (controls). After one week, within the same treatment, the LMIC was significantly improved (p < 0.01). The patients' lymphoproliferative response to IL-2, before any treatment, was not significantly different from that of controls (p < 0.05). However, significantly higher values (p < 0.001) were found in patients tested 7 days after the disease onset as compared to those tested after 12 days. One-week cimetidine treatment significantly improved (p < 0.05) the lymphoproliferative response to IL-2 of initially low responders and had no effect on higher responder patients. In contrast to this, after one week of placebo treatment, a significant decrease in the patients' lymphoproliferative response to IL-2 could be observed as compared to patients' initial responses (p < 0.05) or to those of controls (p < 0.05). Although the number of cases is very small. The data suggest that after cimetidine treatment, as compared to placebo, healing from skin rash and pain was achieved in a significantly shorter time (p < 0.01).

Proliferación de leucocitos de sangre periférica en presencia de sueros de pacientes con cáncer cervicouterino e interleucina-2 recombinante / Proliferation of peripheral blood lymphocytes in presence of sera from patients with cervical cancer and interleukin-2

Diversos estudios han centrado su atención en el establecimiento de una técnica que permita activar y hacer responder de forma específica a linfocitos del paciente contra su propio tumor. Esto se ha conseguido en ocasiones activando linfocitos con mitógenos endógenos, como la interleucina-2 (IL-2). Sin embargo, se ha encontrado que algunos tumores secretan al torrente sanguíneo factores inhibidores de este tipo de respuesta inmune. Con la finalidad de determinar si las células de cáncer de cérvix (CaCu) secretan al torrente sanguíneo factores inhibidores de la respuesta proliferadora de linfocitos, en este trabajo se utilizaron sueros de 12 pacientes con CaCu en cultivos de leucocitos de sangre periférica (LSP). Para evaluar la posible inhibición de estos sueros en la activación mediada por la IL-2, se utilizaron tanto LSP de pacientes con CaCu como de donadores normales. Los resultados obtenidos muestran que in vitro no existe inhibición de la activación a la proliferación de LSP provenientes de pacientes con CaCu por la rIL-2, tanto en presencia de sueros normales como de pacientes con CaCu. En consecuencia, estos resultados indican que las células malignas que constituyen al CaCu probablemente no secretan factores inhibidores de la activación linfocitaria y que los LSP de estos pacientes no han perdido la capacidad de ser activados por la IL-2.

O estudo da resposta imune em pacientes com infecçäo pelo vírus da imunodeficiência humana (HIV) em relaçäo ao antígeno de Mitsuda / The study of immune reponse in patients with infection by HIV in relation to Mitsuda's pathogen

Os autores apresentam resultados de estudo da resistência à infecçäo hansênica em 22 pacientes HIV positivos do Hospital Universitário Clementino Fraga Filho, da Universidade Federal do Rio de Janeiro, mediado pela correlaçäo clínico-patológica do Teste de Mtsuda e outros parâmetros. A amostragem evidenciou 77% de reaçöes negativas, 13% duvidosas e 9% positivas. A observaçäo histológica da reaçäo de Mitsuda mostrou granuloma tuberculóide em nove pacientes (40%) em diferentes fases de formaçäo, permitindo aos autores concluir que a infecçäo pelo HIV diminui sensivelmente, de forma lenta e graudal, a capacidade dos indivíduos de formarem granuloma tuberculóde e de lisar Baar, jogando-os para uma faixa de menor reatividade defensiva constitucional, mais próxima do pólo virchowiano. Atribuem a disfunçäo básica a alteraçöes do linfócito T colaborador e seus subprodutos, principalmente a interleucina II e o interferon

T cell derived cytokines in lung-phase immunity to Schistosoma mansoni

In C57Bl/6 strain mice vaccinated with radiation-attenuated cercariae of Schistosoma mansoni immune elimination of challenge parasites occurs in the lungs. Leococytes were recovered from the lungs of such mice by bronchoalveolar lavage and cultured in vitro with larval antigen; the profile of cytokines released was then analyzed. From 14 days after vaccination, BAL cultures contained infiltrating lymphocytes wich produced abundant quantitties of IFN-g and IL-3. Challenge of vaccinated mice resulted in a second influx of IFN-g nd IL-3- producing cells, earlier than after vaccination or in the appropriate contropls. Ablation studies revealed that CD4+ T cells were the source of IFN-g. The timing of cytokine production after vaccination, and challenge was coincident with the phases of macrophage activation previously reported. At no time could lymphocytes in BAL cultures to stimulated to proliferate with either larval Ag or mitogen, in contrast to splenocytes from the same mice. Furthermore, T cell growth factor activity was not detected in BAL cultures stimulated with Ag. We suggest that the lymphocytes recruited to the lungs are memory/effector cells, When Ag. released challenge schistosomula is presented to these cells, they respond by secreting cytokines wich mediate the formation of cellular aggregates around the parasites, blocking their onward migration

Evaluación in vitro de la producción de interleukina 2 por linfocitos de pacientes con enfermedad de chagas / Evaluation in vitro of the interleukin 2 production from lymphocytes of patients with chagas disease

La interlucina 2 (IL2) es una linfoquina clave para la proliferación de los linfocitos tanto frente a antígenos específicos, como frente a activadores policlonales. En este trabajo fueron estudiados 12 pacientes con infección chagásica, sin evidencia de cardiopatía, se obtuvieron linfocitos de sangre periférica y se incubaron en placas de 96 pozos en presencia de epimastigotes. Los promedios de las unidades producidas por linfocitos INF frente a PHA son más altos que los obtenidos en los CDM. Se concluye demostrando que linfocitos de INF producen más niveles de IL 2 cuando son estimulados por PHA

Receptor de interleucina-2 (primera parte) / Receptor of interleukin-1 (first part)

Como todo factor de crecimiento, la interleucina-2 (IL-2) necesita unirse a un receptor específico, el IL-2 (IL-2R), para mediar su actividad. Este receptor se diferencia de los estudiados en endocrinología en que un factor no específico (IL-2) promueve una expansión clonal antígeno específica, sin inducir los IL-2R hasta que el receptor de antígeno es activado. El sistema se complica al descubrise dos tipos de receptores para el IL-2, los de alta y baja afinidad. La explicación molecular, genética e importancia biológica del IL-2R se describe en el presente artículo, así como la trascendencia del empleo de las técnicas de anticuerpos monoclonales y de recombinación genética en la caracterización del IL-2R. Y teniendo como base dicha caracterización explicar algunos de los mecanismos que se proponen para la transducción de la señal y que culminan con la inducción de nuevos receptores para IL-2 y una proliferación celular