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Biomedical subjects

B Mukherji

Publications and source records attributed to B Mukherji.

At least 55 records · Page 3Linked to original sources
PubMed1987

Cell-mediated amplification and down regulation of cytotoxic immune response against autologous human cancer.

The cytotoxic host immune response toward autologous human cancer may be regulated by the immunoregulatory network. Here we show that helper T cells, cloned from peripheral blood lymphocytes that were sensitized in vitro against an autologous human malignant paraganglioma, proliferated against and made interleukin 2 when cocultured with the tumor-associated antigen in the presence of autologous accessory cells. Furthermore, the helper cell clones amplified cytotoxic immune response by peripheral blood lymphocytes against the paraganglioma cells in coculture with the blood lymphocytes and the paraganglioma cells. An autologous T cell line bearing suppressor phenotype, established from a lymph node that had been infiltrated with the paraganglioma tumor cells, in contrast to the helper cells, selectively suppressed the cytotoxic immune response by the blood lymphocytes against the paraganglioma cells in identical coculture. These results, therefore, demonstrate the existence of cell-mediated immunologic regulations of the cytotoxic immune response (concurrent amplification and suppression in the same host) against an autologous human tumor.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1987

T-cell surface molecules involved in the induction and expression of lymphokine-activated killing of autologous and allogeneic tumor targets.

The cellular interactions and the surface molecules involved in the generation and the expression of lymphokine-activated killer-cell (LAK) activities in vitro in blood mononuclear cells (BMN) from cancer patients and healthy individuals against autologous and allogeneic tumors were studied. The depletion of a plastic-adherent population(s) from BMN at the initiation of in vitro cultures in recombinant interleukin-2 (rIL-2) markedly interfered with the generation of LAK activities. Readdition of the same number of irradiated autologous plastic-adherent cells to the nonadherent population restored the generation of LAK. The requirement of the plastic-adherent population(s) in in vitro induction of LAK activities was observed only in autologous situations. Furthermore, selective modulations of CD3 and CD2 receptors on BMN with the appropriate monoclonal antibodies (MAb) during the induction phases of LAK responses profoundly inhibited the generation of LAK. Thus, unhindered expression of CD2 molecules and CD3 molecules were necessary for the maximum cytotoxic activation of non-antigen-driven effector cells in short-term cultures in rIL-2.

Antigen-Presenting Cells↗
PubMed1987

Activation of autoreactive cytolytic T lymphocyte clone against human melanoma by anti-T3 monoclonal antibody and autologous accessory cells.

A cytotoxic T-lymphocyte (CTL) clone Tc1.8 was derived in a limiting dilution culture from a single cell that was derived from melanoma-involved lymph node lymphocytes activated in in vitro coculture against the autologous melanoma cells (VIP). The clone Tc1.8 (T3+, T8+, T4-, and Leu7-) expressed restricted cytolytic activity against only the autologous target VIP. As it aged in continuous culture containing interleukin 2, Tc1.8 lost cytolytic activity. The cytolytic function could be restored, however, with monoclonal antibody (MoAb) against T3 (OKT3) or with F(ab')2 fractions of OKT3, and upon restimulation with irradiated accessory cells. OKT3-mediated reinduction of cytotoxicity by the aged Tc1.8 could not be achieved if the T3 molecules were modulated from the effector cell surface following overnight incubation of Tc1.8 with saturating concentrations of OKT3 MoAb. Following reactivation with OKT3 Tc1.8 gained cytolytic function against NK targets in addition to VIP. Reactivation with F(ab')2 fractions of OKT3 and with autologous accessory cells, however, maintained its restricted antigen fidelity. The NK-like activity of Tc1.8 upon reactivation with OKT3 resulted from conjugate formation between the activated Tc1.8 and NK targets via the activating ligand itself. Thus, upon stimulation with anti-T3 MoAb and with autologous accessory cells, independently, the autoreactivity could be restored in an aged and inactive CTL clone.

Antibodies, Monoclonal↗
PubMed1987

Oxygen-sensitive 19F NMR imaging of the vascular system in vivo.

The fluorine nuclear magnetic resonance spin-lattice relaxation rate (1/T1) of the perfluorochemical blood substitute perfluorotripropylamine (FTPA) is very sensitive to oxygen tension. This presents the possibility of measuring blood oxygen tension by 19F MR imaging. We obtained oxygen-sensitive 19F NMR images of the circulatory system of rats infused with emulsified FTPA. Blood oxygenation was assessed under conditions of both air- and 100% O2-breathing. T1 relaxation times were derived from MR images using a partial saturation pulse sequence. The T1 times were compared with a phantom calibration curve to calculate average blood pO2 values in the lung, liver, and spleen. The results showed marked, organ-specific increases in blood oxygen tension when the rat breathed 100% O2 instead of air.

Animals↗
PubMed1986

Regulation of cellular immune response against autologous human melanoma. I. Evidence for cell-mediated suppression of in vitro cytotoxic immune response.

The potential existence of down-regulation of cytotoxic immune response against an autologous human melanoma line was investigated as a possible explanation for cytotoxic unresponsiveness against the autologous melanoma cells. The melanoma cell line, PJ-M, was established and lymph node resident lymphocytes (LNL) were isolated from a lymph node which was partially infiltrated with the melanoma cells. Autologous peripheral blood lymphocytes (PBL) were sensitized in in vitro co-culture (IVC) against radiated PJ-M cells in the presence or absence of PJ-M-sensitized LNL and enriched suppressor (OKT8+) or inducer (OKT4+) LNL populations, and were assayed for cytotoxicity in a 4-hr 51Cr-release microcytotoxicity assay. Significant cytotoxic response against PJ-M could be generated in the PBL, but not in the LNL. The addition of sensitized, unfractionated LNL, OKT8+, or OKT4+ LNL populations abrogated cytotoxic response in the PBL against PJ-M. The suppression of cytotoxic response was induced selectively against the PJ-M targets, because IVC of PBL in the presence of the sensitized LNL did not affect the generation of polyclonal cytotoxic alloreactivities, nor did they abrogate the generation of cytotoxic response against allogeneic targets in IVC against the corresponding allogeneic targets. These results suggest the possibility that cytotoxic immune response against the autologous melanoma cells might have been suppressed by the individual's own immunoregulatory circuit.

Antibodies, Monoclonal↗
PubMed1986

Regulation of cellular immune response against autologous human melanoma. II. Mechanism of induction and specificity of suppression.

The cytotoxic immune response in the peripheral blood lymphocytes (PBL) against an autologous malignant melanoma cell line, PJ-M, was found to be down-regulated in in vitro co-culture (IVC) selectively by unfractionated resident lymph node lymphocytes (derived from a lymph node infiltrated with the PJ-M melanoma cells) and T4+ as well as T8+ fractions of the resident lymph node-derived lymphocytes. In this study, the mechanism involved in, and the specificities of, cytotoxic immune response in this autologous system were examined at population and clonal levels. Resident lymph node lymphocytes were isolated from both involved and uninvolved lymph nodes from the same patient. Resident lymphocytes from both sources regulated the generation of cytotoxic immune response when both types of resident lymph node lymphocytes were further sensitized against the PJ-M cells in IVC and were expanded in interleukin 2 (IL 2). An IL 2-dependent homogeneous lymphocyte line (I-10:1) bearing the phenotype of a helper T cell (T4+) and a T4+ clone (I-10.3) of the I-10:1 line, established by limiting dilution culture, also down-regulated the generation of cytotoxic immune effector cells in the PBL in IVC against the PJ-M targets. The IL 2-dependent T4+ inducer line I-10:1 generated a functionally differentiated T8+ suppressor population(s) that, in turn, could abrogate cytotoxic response in fresh PBL in IVC against PJ-M cells. The inducer line I-10:1 and its subclone I-10.3 suppressed the generation of cytotoxic effector cells in the PBL in IVC selectively against the autologous PJ-M cells. Generation of cytotoxic allo-response in IVC was unaffected by the inducer lines. These results provide further evidence for the involvement of the regulatory network in cytotoxic immune response in an autologous human tumor system, and suggest a potential explanation for cytotoxic unresponsiveness against autologous melanoma cells.

Cytotoxicity Tests, Immunologic↗
PubMed1986

Suppressor cell activities in autologous human tumor systems. Suppression of tumor immunity.

Autologous T-cell clones or lines, established from peripheral blood lymphocytes (PBLs) and lymphocytes from tumor-affected lymph nodes, were used to examine the immunoregulatory circuitry that might influence cell-mediated cytotoxic responses against human cancers. In a chromium 51-release microcytotoxicity assay, PBLs, when activated in vitro against autologous tumor cells in interleukin-2, generated marked cytotoxicity against the autologous targets. In four solid-tumor systems, such generation of cytotoxicity in the PBLs could be suppressed by T-cell lines or clones derived from lymphocytes from tumor-affected lymph nodes (LNLs). The suppressions, mediated by both T8+ suppressor and T4+ suppressor-inducer cells, were restricted against only the autologous tumors in two systems. In the other cases, the suppressions were nonspecific. Clarification of the receptors through which these types of regulation are mediated might provide a new approach for immunotherapeutic manipulations in cancer.

Culture Techniques↗
PubMed1985

Magnetic resonance imaging of fluorine in rats infused with artificial blood.

An MRI pulse sequence has been developed that enables the visualization of a perfluorocarbon (PFC) emulsion in the vascular system of rats. Images were made at 0.12T on a clinical imaging system using a small receiver coil, at intervals of approximately 2 hours, two days, two weeks, and two months after replacement of 50% of total blood volume. The most successful technique produced PA projections of the entire torso for both the fluorine and proton components. Direct comparison allowed identification of PFC in heart, lung, liver, spleen, and large vessels both in vivo and postmortem. Potential clinical applications to vascular imaging are discussed.

Animals↗
PubMed1985

In vitro cytotoxicity and transplantation protection by autologous natural and activated killer cells against an in vitro transformed tumorigenic fibroblast line. A case study.

Cytotoxic immune response by autologous natural killer (NK) cells against a spontaneous in vitro transformed tumorigenic fibroblast line, VIP-F:T, was studied in a 4 h 51Cr-release microcytotoxicity assay and in a tumor cell neutralization technique in vivo in nude mice. Although highly cytotoxic against the NK prototype target K562, the autologous NK cells in their nascent state were only marginally cytotoxic against VIP-F:T and unreactive against the autologous normal fibroblasts, Pen-F2. Autologous NK activity against VIP-F:T could, however, be induced by 2-16-h treatment of the NK cells with several species of interferon and by interferon-free interleukin 2 (IL-2). In vitro co-culture (IVC) in IL-2 of autologous peripheral blood lymphocytes (PBL) against VIP-F:T was shown by fluorescence activated cell sorting and by cold target competition experiments to generate almost exclusively an effector population bearing HNK-1 and Leu-11a phenotypes which exhibited receptor specificity for VIP-F:T distinct from receptors on Pen-F2 or K562 cells. PBL, co-cultured in IL-2 against Pen-F2 or K562, or cultured in IL-2 alone, generated high levels of nonspecific killing and showed no receptor specificity. Identical IVC in IL-2 of autologous PBL against a melanoma line, VIP (PBL and the VIP line derived from the same patient from whom the VIP-F:T line was also derived), and similar IVC in IL-2 of several other autologous PBL against their corresponding target cell lines (established from surgical specimens) generated cytotoxic responses involving cytotoxic populations bearing T8 as well as HNK-1 phenotypes; but the cytotoxic activities in none of these systems showed target receptor specificity. Autologous PBL, co-cultured against VIP-F:T in IL-2, were shown to be capable of rejecting tumorigenic challenge with VIP-F:T.3 (a clone of VIP-F:T) in nude mice at effector to VIP-F:T ratio of 10:1. The protective effect of the co-culture activated PBL was abrogated if the HNK-1+ cells were depleted from the effector population. Our data, thus, demonstrate specificity of cytotoxic reactivity which, by phenotypic markers, can be characterized as HNK-1 and Leu 11a+ cells under these experimental conditions against this particular in vitro transformed VIP-F:T line. In addition, this study shows that similar studies of cytotoxic autologous reactivities against in vitro transformed target cell lines will provide valuable information on the subject of NK-mediated surveillance against human neoplasia.

Animals↗
PubMed1984

The role of cytoplasmic intermediates in IL 2-induced T cell growth.

In previous studies we showed that PHA-stimulated human peripheral blood lymphocytes contain an extractable cytoplasmic protein that is capable of inducing DNA synthesis in isolated quiescent nuclei. This factor, which we have called ADR (for activator of DNA replication), appears to represent an endogenous intracellular mitogen, or cytoplasmic transducer of extracellular mitogenic signals. In light of the known role of IL 2 in PHA-induced T cell mitogenesis, we continued these studies to investigate whether ADR may be involved in the mechanism of action of IL 2. Results from both dose-response and time-response studies strongly suggest a functional role for ADR in IL 2 mediated T cell growth. Furthermore, the absence of ADR in dexamethasone-treated, PHA-stimulated cells suggests that the induction of ADR is not an early event in T cell activation associated with the expression of IL 2 receptors; rather, the induction of ADR appears to be a later event resulting directly or indirectly from the binding of IL 2 to IL 2-responsive cells. In sum, our findings suggest a pathway for T cell growth in which extracellular exogenous mitogenic signals are transmitted to the nucleus first through an extracellular endogenous growth factor (IL 2) and finally through an intracellular, endogenous molecule (ADR) that acts at the level of the nucleus itself.

Blood Proteins↗
PubMed1984

Spontaneous in vitro transformation of human fibroblasts.

The establishment of a spontaneously transformed tumorigenic human fibroblast line, VIP-F:T, is described. This line was developed from a primary culture of normal skin from a donor from whom a separate nontransformed fibroblast line, Pen-F2, also was established. The transformed line VIP-F:T exhibited aneuploid karyotype with a marker chromosome, showed anchorage-independent growth, and produced progressively growing tumors with morphologic characteristics of sarcoma in CD-1 (nu/nu) nude mice. The normal fibroblast line Pen-F2 exhibited diploid karyotype, showed no anchorage-independent growth, and produced no tumors in the nude mice. The spontaneously transformed fibroblast line VIP-F:T and its normal counterpart Pen-F2 will be valuable in studies of oncogene expression and in other investigations relevant to neoplasia.

Cell Division↗
PubMed1983

Clonal analysis of cytotoxic T cell response against human melanoma.

We investigated the feasibility of generating cytotoxic T cell clones against autologous human melanoma cells using a melanoma cell line (VIP) and a spontaneously transformed autologous fibroblast line (VIP-F:T). Cytotoxic lymphocytes (CL) generated against the VIP melanoma cells in one-way mixed lymphocyte-tumor cell interactions were expanded in interleukin 2 for 2 wk. The expanded CL were cloned in limiting dilution. Two phenotypically homogeneous clones (3:1 and E.5) were obtained bearing OKT3 phenotype. Both clones expressed cytotoxicity selectively only against the sensitizing autologous target VIP. cytotoxicity assays performed with clone E.5 against the VIP target cells in the presence of autologous unfractionated lymphocytes or serum showed no modulation of autoreactivity of clone E.5. These results indicate that analysis of cellular immune response against autologous tumor cells might be feasible using autoreactive clones generated by the currently available in vitro cloning technology.

Antibodies, Monoclonal↗
PubMed1983

Functional hybrids between human cytotoxic T and mouse myeloma cells.

The establishment of functional human cytotoxic T lymphocyte (CTL) hybrids was investigated. Human CTL, generated in a seven-day, one-way mixed lymphocyte-tumor cell interaction (MLTI) against an allogeneic melanoma cell line (DW) in the presence of a third-party helper cell line and crude interleukin 2 (IL2), were fused with a mouse myeloma cell line (P3-X63 Ag8). Following fusion in polyethylene glycol, the hybrids were examined for cytotoxic potential against the sensitizing target cells DW. Hybrids with detectable levels of cytotoxicity were cloned in soft agar. Two clones demonstrating stable activity were selected for analysis of lineage and specificity of cytotoxicity. Both clones expressed cytotoxicity in a reasonable stable manner without dependence on IL2 for growth or function. Interferon had no effect on the cytotoxicity of the hybrids against the natural killer (NK)-sensitive target cells K562 or the DW cells. The cytotoxic activities of the hybrids against the sensitizing target cells DW, however, could be markedly facilitated in the presence of IL2-containing supernatants in the assay medium and less so in the presence of lectin. The range of the cytotoxic activities of the two clones was identical and restricted to the DW cells and another melanoma cell line, suggesting the possibility of a shared target molecule(s) between these two target cells for these cytotoxic hybrids. These observations indicate that the hybrids might require a mediator present in IL2 supernatant for optimum expression of cytotoxicity and suggest that the hybrids express the cytotoxic specificity of the hybridized CTL. These hybrids offer unique opportunities for critical examination of the molecular mechanisms of cellular cytotoxicity and specificities exhibited by activated human CTL.

Animals↗