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Biomedical subjects

B Mukherji

Publications and source records attributed to B Mukherji.

At least 19 recordsLinked to original sources
PubMed2000

Stimulatory and inhibitory differentiation of human myeloid dendritic cells.

Dendritic cells (DCs) play a critical obligate role in presenting antigens to T cells for activation. In the process, upon antigen capture, DCs undergo maturation and become more stimulatory. Human myeloid DCs can be generated from various sources, including blood, bone marrow, and CD34(+) stem cells. As such, plastic-adherent monocytes from circulation have served as a ready source for generating myeloid DCs in culture in granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4) for translational research in active specific immunotherapy, especially in cancer, with the belief that they are essentially stimulatory or "immunogenic." Here we show that in vitro cultures of plastic-adherent circulating monocytes in GM-CSF and IL-4 followed by further maturation in interferon-gamma plus bacterial superantigens (DC maturing agents) can give rise to two diametrically opposite types of DCs-one stimulatory and another inhibitory. The stimulatory DCs express higher amounts of costimulatory molecules, synthesize IL-12, and efficiently stimulate naive allogeneic T cells in mixed lymphocyte reaction (MLR). The inhibitory DCs, in contrast, express lower concentrations of the critical costimulatory molecules, synthesize large amounts of IL-10, and are nonstimulatory in allogeneic primary MLR. Moreover, while the stimulatory DCs further amplify proliferation of T cells in lectin-driven proliferation assays, the inhibitory DCs totally block T cell proliferation in similar assays, in vitro. Most interestingly, neutralization of the endogenously derived IL-10 with anti-IL-10 antibody in DC cultures repolarizes the inhibitory DCs toward stimulatory phenotype. Accordingly, these observations have important implications in translational research involving myeloid DCs.

Cell Differentiation↗
PubMed2000

Increased intraocular pressure and visual field defects in high resistance wind instrument players.

OBJECTIVE: In this twofold study, part 1 aimed to determine whether the playing of high resistance wind instruments elevates intraocular pressure (IOP) and if so, to investigate the mechanism of IOP elevation and whether its magnitude differs while playing high resistance versus low resistance instruments. The purpose of part 2 was to evaluate whether high resistance players have a greater incidence of glaucomatous changes than other musicians. DESIGN: Three case reports and a cross-sectional study. PARTICIPANTS: Two players of high resistance instruments and one player of high and low resistance wind instruments participated in part 1 of the study. Nine high resistance wind players, 12 low resistance wind players, and 24 nonwind players were recruited among professional musicians in the Boston area to participate in part 2. INTERVENTION: In part 1, IOP and uveal thickness changes were measured by pneumatonometry and ultrasound biomicroscopy in two participants playing their high resistance wind instruments (trumpet and oboe) and in a third participant playing both high (trumpet) and low (clarinet and saxaphone) resistance instruments. Each musician in part 2 underwent medical and musical history, measurement of IOP, Humphrey visual field testing, slit-lamp examination, gonioscopy, and dilated examination. MAIN OUTCOME MEASURES: Intraocular pressure and uveal thickness changes, and visual field loss and optic nerve head appearance were the main parameters measured in part 1 and part 2, respectively. RESULTS: In part 1, pneumatonometry showed IOP elevation dependent on the force of blowing, and ultrasound biomicroscopy revealed uveal thickening associated with IOP elevation. The magnitude of IOP elevation was dependent on the amount of expiratory resistance provided by the particular instrument. Part 2 showed that life hours of high resistance wind instrument playing had a significant relationship to abnormal visual field (P = 0.03) and corrected pattern standard deviation (CPSD) scores (P = 0.007) in univariate logistic regression and univariate linear regression, respectively. A 0.011-unit increase in CPSD for each 1000 life hours of high resistance wind playing was found. CONCLUSIONS: High and low resistance wind musicians experience a transient rise in their IOP while playing their instruments as a result least in part of uveal engorgement. The magnitude of IOP increase is greater in high resistance wind players versus low resistance wind players. High resistance wind musicians had a small but significantly greater incidence of visual field loss (abnormal fields and increased CPSD scores) than other musicians, which was related to life hours of playing. The cumulative effects of long-term intermittent IOP elevation during high resistance wind instrument playing may result in glaucomatous damage, which could be misdiagnosed as normal-tension glaucoma.

Aged↗
PubMed1999

Emergence of regulatory CD4+ T cell response to repetitive stimulation with antigen-presenting cells in vitro: implications in designing antigen-presenting cell-based tumor vaccines.

Because APCs play a crucial role in the generation of T cell-mediated immune responses, numerous clinical trials with APC-based vaccines have been initiated in different types of human cancers. Encouraging results have emerged from some of these initial studies. Thus far, APC-based vaccinations usually include multiple rounds of immunization. With this approach, although we and others have detected induction of Ag-specific CTL responses in vaccinated patients after stimulation with the same APC-based immunogen, in vitro we also find that repetitive in vitro stimulation with Ag-loaded APC can, at times, lead to the emergence of noncytolytic CD4+ T cells exhibiting the characteristic phenotype of Th2 cells. These noncytolytic CD4+ T cells synthesize large quantities of type 2 cytokines such as IL-4 and IL-10 on stimulation with the autologous APC or tumor cells in an MHC class II-restricted manner. Further, these CD4+ T cells and a cell-free supernatant factor block the activation of fresh T lymphocytes. The supernatant factor also exhibits a marked inhibitory effect on the expression of the costimulatory molecules, CD80 and CD86, by APC. The inhibitory effect of the supernatant factor can be abrogated by neutralizing IL-10 in the supernatant. These observations therefore have implications in the APC-based tumor vaccine protocol design.

Antigen-Presenting Cells↗
PubMed1999

Varicella zoster virus infection associated with high-dose chemotherapy and autologous stem-cell rescue.

A retrospective evaluation of 215 consecutive recipients of high-dose chemotherapy (HDC) and autologous stem cell rescue (ASCR) was conducted to ascertain the incidence, temporal course, and outcome of varicella zoster virus (VZV) infection. Herpes zoster was identified in 40 individuals at a median of 69 days following ASCR. Six of these cases occurred at a median of 33 days prior to ASCR but following the initiation of high doses of stem cell mobilization chemotherapy. Twenty-five percent of patients demonstrated cutaneous or systemic dissemination and 32.5% required medical intervention for post-herpetic neuralgia. All except two individuals received antiviral chemotherapy. One patient with active VZV infection died of multiorgan failure 39 days after ASCR. Multivariate analysis of risk factors disclosed the significance of prophylactic acyclovir use in Herpes simplex virus seropositive individuals in reducing the risk of VZV infection. Moreover, the use of busulfan, thiotepa and carboplatin as the conditioning chemotherapy regimen was associated with an increased risk of subsequent VZV infection. The incidence of VZV reactivation after HDC and ASCR is similar to that observed following bone marrow transplantation but has an earlier onset. This may be related to an earlier induction of immunosuppression by stem cell mobilization chemotherapy administered prior to ASCR. We demonstrated a marked reduction in the proliferative and synthetic capacities of peripheral blood mononuclear cells obtained prior to and following stem cell mobilizing chemotherapy. Moreover, greater than 80% of VZV infections occurred within 6 months following ASCR and late cases were seldom observed compared to allogeneic and autologous bone marrow transplantation. The role of antiviral chemoprophylaxis during the period of maximum immunocompromise needs to be studied further in the HDC-ASCR setting.

Adult↗
PubMed1999

Myeloablative chemotherapy with autologous peripheral blood stem cell transplantation for metastatic breast cancer: immunologic consequences affecting clinical outcome.

Autologous peripheral blood stem cell transplantation following myeloablative chemotherapy is being increasingly utilized in the treatment of a variety of malignancies. We administered busulfan 16 mg/kg orally, thiotepa 500-700 mg/m2 i.v., and carboplatin 800-1000 mg/m2 i.v. to 56 women with metastatic carcinoma of the breast. Autologous peripheral blood stem cells, which had been collected after a combination of chemotherapy and granulocyte colony-stimulating factor, were infused on day 0. The major toxicities of the conditioning regimen included severe pancytopenia, stomatitis, nausea, emesis, diarrhea, fever, and infection. Transplant-related mortality was 1.8%. The incidence of opportunistic viral infections was 42.9%. Fourteen individuals achieved a complete response. The actuarial survival at 1223 days was 13.7% for the entire group of patients; the actuarial survival at 1009 days was 39.3% among complete responders. The functional status of the immune system was determined following transplantation in a subset of patients. Peripheral blood mononuclear cells were obtained before and after stem cell infusion, and were analyzed phenotypically and functionally. Proliferative and interleukin-2 synthetic ability of these cells was assessed following stimulation with phytohemagglutinin and anti-CD3 antibody. The response to influenza peptides was also ascertained. Proliferative and interleukin-2 synthetic capacity was markedly impaired for over a year. Memory response was virtually absent for up to 2 years following transplantation. The prolonged and marked immunosuppression following this myeloablative regimen was associated with a high incidence of opportunistic viral infections, and may have contributed to disease relapse and progression especially in patients who failed to achieve a complete response following transplantation.

Administration, Oral↗
PubMed1999

Stimulatory and inhibitory maturation of human macrophage-derived dendritic cells.

Circulating human macrophages are often used to generate dendritic cells (DCs) by culturing them in granulocyte macrophage-colony stimulating factor (GM-CSF) and interleukin-4 (IL-4). As DCs are superb antigen-presenting cells, these types of myeloid DCs are now used in many DC-based vaccination protocols, especially in cancer, with the belief that they are essentially stimulatory or 'immunogenic'. Here we show that just as peripheral macrophage-derived myeloid DCs can be stimulatory, in vitro cultures of myeloid DCs in GM-CSF and IL-4 followed by further maturation in interferon-gamma plus bacterial superantigens (as DC maturing agents) can give rise to DCs that are functionally inhibitory. The stimulatory DCs express higher amounts of costimulatory molecules, synthesize IL-12, and efficiently stimulate naive allogeneic T cells in mixed lymphocyte reaction (MLR). The inhibitory DCs, in contrast, express lower concentrations of the critical costimulatory molecules, synthesize large amounts of IL-10, and are either marginally stimulatory or nonstimulatory in MLR. Moreover, while the stimulatory DCs further amplify proliferation of T cells in lectin-driven proliferation assays, the inhibitory DCs suppress T cell proliferation in similar assays, in vitro. Most interestingly, neutralization of the endogenously derived IL-10 with anti-IL-10 antibody with DC cultures as well as exposure of the inhibitory DCs to CpG oligonucleotides or to in vitro activated autologous CD4+ T helper cells repolarize them into stimulatory phenotype. Accordingly, these observations have important implications in translational research involving myeloid DCs.

Antigen Presentation↗
PubMed1998

Generation of CD8+ and CD4+ T-cell response to dendritic cells genetically engineered to express the MART-1/Melan-A gene.

Both CD8+ and CD4+ T cells have demonstrated roles in antitumor immune response in many animal tumor systems. In many human tumor systems, although abundant literature exists on the evidence of tumor antigen-specific CD8+ CTL response, only limited information is available on tumor antigen-specific CD4+ T-cell response. Using the MART-1/Melan-A (MART-1) antigen system as a prototype human tumor-associated antigen (TAA)- and dendritic cell (DC)-based MART-1 antigen presentation system (i.e., DCs transduced with an adenoviral vector-based construct carrying the MART-1 gene), we explored, in vitro, the feasibility of generating both CD8+ and CD4+ T-cell responses in the same individual. Here, we show that autologous DCs from both HLA-A2-positive melanoma patients and normal healthy individuals that are transduced with an adenoviral vector containing the MART-1 antigen are capable of inducing both MART-1-specific CD8+ and CD4+ T cells in in vitro coculture. After several rounds of stimulation, both the CD4+ and CD8+ T cells synthesized IFN-gamma when they were specifically stimulated. The CD8+ T cells generated in such cocultures also recognized the MART-1(27-35) peptide, AAGIGILTV, in 4-h cytotoxicity assays. These observations, therefore, suggest that Th1-type responses can be generated, in vitro, by stimulation with DCs that are genetically modified to express a TAA. Although the outcome of this type of genetically engineered DC-based stimulation may vary from system to system, this type of in vitro antigen presentation may be very useful in more comprehensive analyses of CD4+ T-cell response to defined TAAs, and such genetically engineered autologous DCs might be better candidates to serve as surrogate cancer vaccines.

Antigens, Neoplasm↗
PubMed1998

Generation of melanoma-specific cytotoxic T lymphocytes by dendritic cells transduced with a MART-1 adenovirus.

Dendritic cells (DC) are potent stimulators of primary T cell responses. In this study, we demonstrate that DC, genetically engineered to express the MART-1/Melan-A (MART-1) tumor-associated Ag, express MART-1 mRNA and protein, correctly process and present the HLA-A2.1-restricted immunodominant MART-1 peptide (MART-1(27-35)), and serve as potent stimulators of MART-1-specific CTL in vitro. A replication-defective E1-deleted adenovirus (AdV) was constructed that expresses MART-1 (AdVMART1). Transduced DC produce full length MART-1 mRNA as well as MART-1 protein. AdVMART1 does not significantly down-regulate cell surface class I expression despite having an intact E3 region. Transduction of an HLA-A2-positive/MART-1-negative cell line with AdVMART1 renders these cells sensitive to lysis by CTL specific for the MART-1(27-35) immunodominant peptide. In addition, DC transduced with AdVMART1 stimulated MART-1(27-35)-specific tumor-infiltrating lymphocytes to synthesize IFN-gamma. Finally, AdVMART1-transduced DC were able to generate MART-1(27-35) peptide-specific, class I-restricted CTL in PBL cultures from normal donors. This study supports the use of tumor Ag-engineered DC in genetic immunotherapy.

Adenoviridae↗
PubMed1998

Human melanoma-specific, noncytolytic CD8+ T cells that can synthesize type I cytokine.

The existence of CD8+ CTLs that are capable of recognizing MHC class I-bound, human tumor-associated peptide antigens is now unequivocally documented in cancer patients. Thus far, the role of CD8+ T cells in tumor immunity has been predominantly viewed in terms of cytolytic ability as the prime mode of their function. Interestingly, it is increasingly evident that CD8+ T cells are capable of synthesizing both type I and type II cytokines. Thus, it is conceivable that tumor antigen-specific but noncytolytic CD8+ T cells might play an important role in antitumor immune response by synthesizing type I cytokine. Through such cytokines, they could provide "help" for the process of generating as well as in maintaining an effective CD8+ CTL response. In addition, they might recruit other types of effector cells (such as natural killer cells, macrophages, and others) locally at the tumor site. Either way, they could exert a profoundly positive role in cell-mediated antitumor immune response, particularly because the great majority of tumor cells express only MHC class I molecules that present peptide epitopes to CD8+ T cells. Unfortunately, tumor antigen-specific, noncytolytic but type I cytokine-secreting CD8+ T cells have not received much investigative attention. Here we show that CD8+ T cells, isolated from the tumor-infiltrating lymphocytes from human melanoma, synthesize type I cytokine (IFN-gamma and tumor necrosis factor alpha) in a MHC class I-restricted and tumor-specific noncytolytic interaction with the autologous melanoma cells.

Antigens, Neoplasm↗
PubMed1998

Immunization with a tumor-cell-lysate-loaded autologous-antigen-presenting-cell-based vaccine in melanoma.

The discoveries of human melanoma-associated antigens in molecular terms have renewed interest in peptide- or peptide- and antigen-presenting-cell (APC)-based cancer vaccines. Considering the limited scope of immunization using defined peptides, we have studied an alternative approach of specific immunization with tumor-lysate-loaded autologous APC (adherent peripheral mononuclear cells cultured in 1000 U granulocyte/macrophage-colony-stimulating factor for 14 days) as a surrogate vaccine. Seventeen patients (11 with active metastatic disease) were intradermally immunized with the vaccine in a phased dose escalation (10(5)-10(7) cells/injection) monthly for 4 months. Thirteen patients completed all four immunizations showing no toxicity (3 patients had to be taken off study because of progressive disease and 1 patient went off study as a result of myocardial infarction due to multi-vessel coronary artery disease). None has shown any immediate or delayed toxicity attributable to the immunization and none has shown any evidence of autoimmunity. One patient showed a partial regression of a subcutaneous nodule. Thirteen patients are alive after 4+ months to 30+ months (17-month median survival for the group). Nine patients showed evidence of delayed-type hypersensitivity at the vaccine sites. Monitoring of biological response in conventional natural killer or cytolytic T lymphocyte assays with pre- and post-immune peripheral blood lymphocytes revealed no consistent differences. The vaccine-infiltrating lymphocytes (VIL) from nine specimens were adequately expanded following in vitro stimulation with the respective autologous-lysate-loaded APC for phenotypic and functional analyses. Five of the nine ex vivo expanded VIL were predominantly CD8+. Evidence of an antigen-specific CD8+ T cell response (cytotoxicity and/or tumor necrosis factor production) was detected in three of the five CD8+ VIL. These observations suggest that this type of vaccine is feasible, that it has biological activity, and that the approach may be improved through additional strategic manipulations.

Antibody Formation↗
PubMed1996

Enhancement of cytolytic T lymphocyte precursor frequency in melanoma patients following immunization with the MAGE-1 peptide loaded antigen presenting cell-based vaccine.

Identification of human melanoma-associated peptide antigens for CTLs has opened unprecedented opportunities for active specific immunotherapy for melanoma with synthetic peptide. We have shown that immunization with a MAGE-1 gene encoded nonapeptide (EADPT-GHSY)-pulsed autologous antigen presenting cell-based vaccine induces autologous melanoma-reactive and peptide-specific CTL response, in situ, at the vaccination site and at distant tumor deposits in patients who are HLA-A1+ and whose melanoma cells express the MAGE-1 mRNA. Here, we show that such immunization is also capable of increasing the frequency of autologous melanoma-reactive CTL precursors in the circulation. We further show that in vitro stimulation of the postimmunization peripheral blood lymphocytes with the MAGE-1 nonapeptide-loaded antigen presenting cell and interleukin-2 leads to significant expansion of peptide-specific and autologous melanoma-reactive CTL response.

Amino Acid Sequence↗
PubMed1995

Induction of antigen-specific cytolytic T cells in situ in human melanoma by immunization with synthetic peptide-pulsed autologous antigen presenting cells.

Human melanoma cells can process the MAGE-1 gene product and present the processed nonapeptide EADPTGHSY on their major histocompatibility complex class I molecules, HLA-A1, as a determinant for cytolytic T lymphocytes (CTLs). Considering that autologous antigen presenting cells (APCs) pulsed with the synthetic nonapeptide might, therefore, be immunogenic, melanoma patients whose tumor cells express the MAGE-1 gene and who are HLA-A1+ were immunized with a vaccine made of cultured autologous APCs pulsed with the synthetic nonapeptide. Analyses of the nature of the in vivo host immune response to the vaccine revealed that the peptide-pulsed APCs are capable of inducing autologous melanoma-reactive and the nonapeptide-specific CTLs in situ at the immunization site and at distant metastatic disease sites.

Amino Acid Sequence↗
PubMed1995

Presentation of synthetic peptide antigen encoded by the MAGE-1 gene by granulocyte/macrophage-colony-stimulating-factor-cultured macrophages from HLA-A1 melanoma patients.

The recent identification of the sequences of the peptides derived from a number of human melanoma-associated antigens has presented opportunities for developing a specific-peptide-based vaccine in this form of cancer. Since antigen-presenting cells (APC) play a crucial role in the induction of the T-cell-mediated immune response, we examined whether or not ex vivo cultured APC, bearing the appropriate MHC restricting elements, when pulsed with a relevant melanoma-specific cytotoxic-T-lymphocyte (CTL)-determined peptide, can present the peptide to the CTL. Here we show that a population of cells, derived from the monocyte/macrophage lineage from peripheral blood and grown in granulocyte/macrophage-colony-stimulating factor, exhibit many essential characteristics of "professional" APC (dendritic-type morphology with a proportion of the population, the B7 molecule, and high levels of MHC class I and class II molecules, CD11b and CD54 molecules) and are capable of efficiently presenting the nonapeptide, EADPTGHSY, encoded by the melanoma antigen MAGE-1 gene, to the MAGE-1-specific CTL clone, 82/30. These results suggest that this type of autologous ex vivo cultured population of professional APC, when pulsed with the relevant-CTL-determined peptide, can serve as a novel type of candidate vaccine for active specific immunization against HLA-A1-positive patients with melanoma expressing the MAGE-1 antigen.

Amino Acid Sequence↗
PubMed1995

Immunobiology and immunotherapy of melanoma.

The immunobiology of melanoma has dominated the investigative field in tumor immunology. Indeed, the best evidence of immunogenicity of a spontaneously grown human cancer has been found in this model. Yet considerable doubt has lingered on the very issue of tumor immunity in general and on the subject of melanoma immunity as well. To a great extent, the doubt has persisted mostly because of our past inability to define a true tumor antigen. Fortunately, the human melanoma model has given us a remarkable insight into what had been one of the most tenaciously elusive issues in tumor immunology, namely, the structural definition of "tumor antigens": the raison d'être for tumor immunology. This review is confined to the areas of structural definition of melanoma antigens and to the topic of cellular immunity to melanoma because most of the recent findings have occurred in these areas. The topic of melanoma immunotherapy and novel opportunities for immunotherapy in this disease is also discussed.

CD4-Positive T-Lymphocytes↗
PubMed1994

Demonstration of differences in vascular permeability in experimental tumors by use of 19F magnetic resonance imaging.

RATIONALE AND OBJECTIVES: In vivo assessment of tumor vascular permeability may provide useful information for chemotherapy treatment planning or for the assessment of treatment effectiveness. We aimed to assess vascular permeability in two tumor sublines as well as changes in vascular permeability with tumor growth by using 19F magnetic resonance imaging. METHODS: An emulsion of perfluorotributylamine was used as a tumor extravascular contrast agent for 19F MRI. The amount of emulsion that leaked into tumor interstitial space was analyzed qualitatively with imaging. A quantitative study of vascular permeability was done with a separate group of tumors by use of Evans blue dye. RESULTS: One tumor type was more permeable to both perfluorotributylamine emulsion and Evans blue than was the second tumor type. The difference was attributed to a difference in surface area for exchange. In larger tumors of both types, pooling of large amounts of perfluorocarbon occurred and was assumed to be attributable to hemorrhage or blood flow stasis or both. CONCLUSION: 19F MRI is capable of demonstrating the permeability of tumor vessels to macromolecular substances.

Adenocarcinoma↗
PubMed1993

Inhibition of interleukin-2 synthesis and interleukin-2 receptor alpha expression on T cells by a cell-free factor derived from a CD4+ regulatory T cell clone.

We have shown that certain CD4+ T cell lines can function as suppressor cells in a cell culture system. In this context, the CD4+ T cells (AS-9) cloned from the peripheral blood lymphocytes (PBL) of a melanoma patient are capable of suppressing the induction of cytolytic response in autologous PBL in coculture. Here we show that a trypsin-sensitive cell-free culture supernatant factor from the AS-9 cells, AS-9 SF, interferes with IL-2 synthesis by T cells when they are stimulated. AS-9 SF also selectively blocks the expression of interleukin-2 receptor alpha (IL-2R alpha) on T cells during activation. Expression of transferrin receptors and the CD3 molecules is not down-regulated by this factor. The AS-9 SF consequently blocks proliferation of T cells when they are stimulated by lectin or activated through the T cell receptors. AS-9 SF suppresses the IL-2R alpha induction and the T cell proliferation at the induction phase only because it has no suppressive effect on preactivated T cells. Interleukin-2, IL-2R alpha, and beta messages are not down-regulated by the AS-9 SF and the suppressive effect of the AS-9 SF on IL-2R alpha expression and on T cell proliferation is not neutralized by the addition of exogenous recombinant IL-2. The factor does not appear to be IL-4, IL-10, or TGF-beta, three known cytokines possessing regulatory properties on T cell activation.

CD4-Positive T-Lymphocytes↗