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Biomedical subjects

B Mukherji

Publications and source records attributed to B Mukherji.

At least 37 records · Page 2Linked to original sources
PubMed1993

Adoptive immunotherapy with peripheral blood lymphocytes cocultured in vitro with autologous tumor cells and interleukin-2.

A clinical trial of adoptive immunotherapy was carried out with peripheral blood lymphocytes (PBL), cocultured in vitro with autologous tumor cells and interleukin-2 (IL-2), in 14 patients with advanced melanoma. PBL from these patients were cocultured with irradiated autologous tumor cells for 7 days, which was followed by expansion in IL-2-containing medium. These lymphocytes were returned to the patient along with intravenous IL-2 at doses up to 2 x 10(6) IU m-2 day-1. A dose of 300 mg/m2 cyclophosphamide was administered to each patient intravenously 4 days prior to each treatment. Following coculture, the lymphocytes were primarily CD3+ T cells and they expressed varied degrees of cytotoxicity against autologous melanoma cells. In 9 patients the activated cells were at least 80% CD4+ and in 2 cases they were mostly CD8+. Some of the activated cells exhibited suppressor or helper activity in a functional regulatory coculture assay. No major therapeutic response was observed in this study. Minor responses were observed in 2 patients. Toxicities were those expected from the IL-2 dose administered.

Adult↗
PubMed1993

Analysis of cytolytic effector cell response in vitro against autologous human tumor cells genetically altered to synthesize interleukin-2.

Recently, there has been a surge of interest in gene therapy in cancer particularly with cytokine transduced tumor cells as a novel form of tumor vaccine. In two autologous human tumor systems, using the tumor cells engineered to produce interleukin-2 by gene transduction techniques, we have examined whether or not such genetically altered cells are capable of inducing a tumor specific cytolytic T cell (CTL) response, in vitro, in co-culture with the respective autologous peripheral blood lymphocytes (PBL). We found that in neither system did co-cultures of the IL-2 producing tumor cells and the autologous PBL generate much cytolytic effector cell activity directed against the respective tumor cells, although these co-cultures did lead to the generation of substantial levels of natural killer (NK) cell activity when measured against the prototype NK sensitive target K562 line. More surprisingly, the levels of lymphokine activated killer cell responses against the respective autologous targets that could be generated in the PBL with exogenous IL-2 alone were compromised by the presence of the autologous tumor cells in the co-culture.

Antigens, Neoplasm↗
PubMed1993

Measurement of vascular volume in experimental rat tumors by 19F magnetic resonance imaging.

RATIONALE AND OBJECTIVES: In-vivo assessment of tumor vascular volume may provide useful information for treatment planning or the assessment of treatment effectiveness. The goals of our study were to measure percent vascular volume in two experimental tumor sublines using 19F magnetic resonance imaging (MRI) and to assess changes in tumor blood volume with growth. METHODS: An emulsion of perfluorotributylamine (FTBA) was used as a vascular contrast agent for 19F MRI: The amount of emulsion in the tumor vasculature was measured by 19F MRI and used to calculate percent vascular volume. A separate ex-vivo study of vascular volume was conducted using the dye Hoechst 33342. A total of five rats were studied by MRI and 14 by the ex-vivo method. RESULTS: The ranges of percent vascular volume values measured in the imaging and Hoechst dye studies were 2% to 9% and 1.25 to 7%, respectively. A trend toward decreasing percent vascular volume with increasing tumor volume was evident in one tumor subline. CONCLUSIONS: The quantitative 19F MRI technique was effective for measuring percent vascular volume and changes in vascular volume with growth.

Adenocarcinoma↗
PubMed1992

Effect of pharmacological purging on natural killer cell number and activity in human bone marrow.

We assayed natural killer (NK) cell activity and phenotype from human bone marrow (BM) following "purge" with 4-hydroperoxycyclophosphamide (4HC) at 60 micrograms/ml for 30 min in vitro. In all cases studied, lytic activity against the K562 cell line was either significantly decreased or abolished following 4HC purge. Although NK activity was significantly affected by 4HC treatment, no major differences in the phenotype between the purged and unpurged population were seen. Further, while in vitro culture of BM with IL2 resulted in a significant increment of NK activity, no IL-2 responsive cells were found in the 4HC purged BM after 14 days of culture. This study demonstrates that pharmacological purging of bone marrow results in a persistent functional decline of NK cell activity and may serve as a useful model for the study of the ontogeny of NK cells.

Bone Marrow↗
PubMed1992

Fluorinated blood substitute retention in the rat measured by fluorine-19 magnetic resonance imaging.

RATIONALE AND OBJECTIVES: Emulsions of perfluorocarbons (PFCs) have been tested as blood substitutes. However, evidence exists that there is long-term retention of some PFCs by the organs of the reticuloendothelial system (RES). The authors investigate organ retention of the blood substitute component, perfluorotripropylamine (FTPA), using fluorine-19 (19F) magnetic resonance imaging (MRI). METHODS: Various dosages of an emulsion of FTPA were administered to five rats. At intervals up to 86 weeks after infusion, 19F MRI was used to measure the amount of FTPA in liver and spleen. The data were fit to both linear and exponential elimination models, and organ retention half-lives were calculated. RESULTS: The exponential half-lives for combined liver and spleen FTPA ranged from 110 to 190 days. Linear half-lives ranged from 175 to 300 days. CONCLUSIONS: FTPA retained by the liver and spleen may be quantified by 19F MRI: The half-lives that were measured are longer than those reported previously for FTPA.

Animals↗
PubMed1991

Suppression of lymphokine-activated killer cell generation by tumor-infiltrating lymphocytes.

A functional analysis of tumor-infiltrating lymphocytes (TILs) from renal cell carcinoma (RCC) and malignant melanoma was performed. TILs were expanded in recombinant interleukin-2 (50 U/ml) in Iscoves medium. Phenotypic and functional (cytolytic vs regulatory) analyses were carried out with the fresh and expanded TIL populations after 4 weeks in culture. Only one TIL population from an RCC case (out of six cases studied) was CD8+ and demonstrated MHC class I-restricted tumor-specific cytotoxicity against the autologous RCC target. TIL populations from the other five cases became predominantly CD4+ and they neither killed the respective autologous tumor cells nor killed the NK-sensitive target K-562 cells. When studied for other functions, two CD4+ TIL populations were found to suppress the lymphokine-activated killer cell response by peripheral blood lymphocytes (PBL) in coculture. Of these two, a TIL population from an RCC case (MJ TIL) was used to study the cellular and molecular mechanisms of suppression. The MJ TIL synthesized a supernatant factor that blocked activation of resting PBL as measured by the induction of high-affinity IL-2 receptor (IL-2R) when stimulated by phytohemagglutinin but did not down-regulate the fully expressed IL-2R on activated T cells. The suppression of high-affinity IL-2R induction on T cells did not result from tumor necrosis factor-alpha and beta or from transforming growth factor-beta as these cytokines were not detected in the cell-free supernatant from the MJ TIL culture. The supernatant factor also suppressed IL-2-mediated enhancement of cytotoxicity by natural killer (NK) cells without demonstrating direct toxic effect on the NK cells. Thus, when TIL are used for adoptive immunocytotherapy, it may be useful to fully characterize them functionally, in vitro.

CD4 Antigens↗
PubMed1991

Clonal expansion of T cells following in vitro stimulation with autologous melanoma cells and interleukin-2 studied by molecular analysis of a T cell receptor.

Twelve autologous mixed peripheral blood (PBL) tumor cell interactions (MLTC) followed by in vitro expansion of the stimulated T cells in recombinant interleukin-2 (IL-2) were analyzed for the potential emergence of oligoclonal or monoclonal T cell populations in the PBL by Southern blot analysis of the T cell receptor (TCR) beta gene. The emergence of oligoclonal or monoclonal TCR beta gene rearranged populations was seen in 5 of the 12 cases. In 2 of these 5 cases only one dominantly rearranged band was observed. The emergence of oligoclonal or monoclonal T cell populations following stimulation with autologous melanoma cells was associated with predominant CD4 phenotype of the stimulated PBL exhibiting a varied degree of cytotoxicity toward the respective autologous melanoma cells. The evidence of emergence of monoclonal or oligoclonal T cell populations following stimulation with autologous tumor cells strongly supports the existence of T cell-mediated responses against autologous melanomas. Furthermore, cellular and molecular analyses of T cell responses in autologous mixed lymphocyte tumor cell interactions will provide valuable information on the nature of the T cell responses and on the pattern of gene segment usages by the T cells in response to the autologous tumor cells.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1991

A stable perfluorochemical blood substitute.

A stable emulsion of perfluorodecalin, made up of 34 percent (vol/vol) perfluorodecalin dispersed by sonication in isotonic Tyrode's buffer (pH 7.4) containing egg yolk lecithin, has been developed. The viscosity of the emulsion is the same as that of human blood, and the particle size is 0.2 microns in diameter. On storage at 5 degrees C, there was no change in viscosity for up to 60 weeks. At 21 degrees C, viscosity increased after 20 weeks of storage; this increase was considerably diminished by the presence of tocopherol in the emulsion. The accumulation of malondialdehyde indicated that there was continuous slow oxidation of the lecithin on storage of the emulsion at either 5 or 21 degrees C; this oxidation was markedly reduced by the presence of tocopherol.

Animals↗
PubMed1990

Autologous melanoma-induced activation of regulatory T cells that suppress cytotoxic response.

The host immune response toward autologous human cancer is subject to regulation by the immunoregulatory network. We show that certain CD4+ T cell clones, derived from melanoma involved lymph node lymphocytes and from PBL stimulated by autologous melanoma cells, selectively down-regulated the induction of cytotoxic immune response of PBL against the respective autologous melanoma cells in two autologous systems. In both systems, only the generation of cytotoxic response against the autologous melanoma cells were suppressed. Cytotoxic response against EBV-infected autologous lymphoblastoid cell line in one case and cytotoxic responses against allogeneic targets in the other were not affected. In addition to suppressor activity selectively expressed against the autologous melanoma cells, the T cell clones up-regulated their Tac receptors when cocultured with the autologous melanoma cells and APC. These results support the existence of a putative tumor Ag-driven activation of regulatory T cells that affect cytotoxic immune response, in vitro, against autologous human melanoma.

CD4-Positive T-Lymphocytes↗
PubMed1990

T-cell clones that react against autologous human tumors.

T cells (derived from peripheral blood lymphocytes [PBL], lymph nodes or tumor tissues and restimulated with autologous tumor cells and expanded in interleukin-2 [IL-2]), when cloned, produce three functional classes of clone. Class I T-cell clones exhibit the phenotype of alpha/beta cytotoxic T lymphocytes (CD3+, CD8+, CD4-, WT31+), use their CD3-alpha/beta complexes for cognate function, and lyse the autologous tumor cells specifically in a major histocompatibility complex (MHC) Class I-restricted manner. The second class of T cell clone expresses identical phenotype but exhibits a rather broad cytotoxic profile against the autologous and allogeneic tumor cells derived from tumors with similar and/or dissimilar histologies. Although these CTL clones can, at times, show MHC Class I-restricted killing and use their T-cell receptors (TCR) complexes for function, activation via certain accessory molecules, particularly lymphocyte-function associated (LFA-1) antigens, might induce their broad cytotoxic behavior. The nature of the tumor antigen recognized by the Class I antigen-specific CTL clones remains unknown. It is evident, however, that more than one antigen can be associated with a given tumor and they are recognized by different CTL clones from individual patients. The third class of T-cell clone is usually of CD4+ alpha/beta T cells (CD3+, CD4+, CD8-, WT31) and these T-cell clones exhibit no cytotoxicity toward the autologous or allogeneic target cells. When tested for potential regulatory property, one type of CD4+ T-cell clone exhibits the characteristics of helper T cells. This type induces or amplifies cytotoxic response in fresh PBL by elaborating interleukin-2 (IL-2) and interferon-gamma). These helper T-cell clones can proliferate against the autologous tumor cells and demonstrate functional specificity for the autologous tumor cells. The other type of CD4+ T-cell clone exhibits the phenotype of the helper T-cell clone (CD3+, CD4+, CD8-, WT31+) but suppresses the cytotoxic response of the autologous PBL in co-culture in the presence of the autologous tumor cells and exogenous IL-2. In some situations, these CD4+ suppressor T-cell clones exhibit considerable specificity for the autologous tumor cells. They do not suppress the cytotoxic response against allogeneic targets or against EBV-infected autologous lymphoblastoid cells. Furthermore, they specifically up-regulate their IL-2 receptors (IL-2R) when stimulated by the autologous tumor cells or with autologous tumor cell-pulsed antigen-presenting cells.(ABSTRACT TRUNCATED AT 400 WORDS)

Clone Cells↗
PubMed1989

Clonal analysis of cytotoxic and regulatory T cell responses against human melanoma.

T cell-mediated immune response against autologous melanoma cells was analyzed, at population and clonal levels, in 31 patients with recurrent and/or metastatic disease. Fresh PBL and lymph node lymphocytes (LNL) from melanoma-involved nodes were not cytotoxic against the respective melanoma cells. When activated in in vitro coculture (IVC) against the autologous melanoma cells in the presence of IL-2, a majority of the activated PBL and LNL became cytotoxic against the autologous targets. The activated effector cells were cloned in limiting dilution microcultures, and growing clones were phenotypically defined and were functionally characterized for cytotoxicity and for potential regulatory function. Functional T cell clones were obtained from 15 of 31 cases. Of these, CTL responses exhibiting cytotoxicity restricted against the autologous melanoma were seen in four cases. All four CTL clones were CD3+, CD8+, and CD4-. Three of these four CTL clones were studied extensively. All three of these CTL clones expressed MHC class I-restricted cytotoxicity. mAb anti-CD3 blocked cytotoxicity in two and enhanced cytotoxicity in the other. Neither autologous sera nor autologous nonactivated fresh PBL modulated the cytotoxic functions of the CTL clones at the effector phase. T cell lines exhibiting regulatory function were obtained in 11 cases. The regulatory T cell lines were CD3+, CD4+, and CD8-. In three cases CD4+ clones amplified the cytotoxic response in the PBL in coculture, while in eight other cases the T cell lines downregulated the cytotoxic responses. Such T cell-mediated down-regulations were either restricted to the autologous system, induced by D/DR antigens expressed by the autologous or allogeneic melanoma cells, or induced by stimulus other than D/DR antigens. Taken together, these findings clearly demonstrate the existence of T cell-mediated cytotoxic and regulatory responses against human melanoma.

Antigens, Neoplasm↗
PubMed1989

Effects of reduction in drugs or dosage after long-term control of systemic hypertension.

The possibility of discontinuing--compared to reducing--antihypertensive drug treatment was investigated in 606 male hypertensive patients with entry diastolic blood pressure (BP) in the range of 90 to 114 mm Hg. Diastolic BP was controlled at less than 90 mm Hg with 1 of 4 regimens: low dose hydrochlorothiazide (HCTZ), 25 mg twice daily; high dose HCTZ, 50 mg twice daily; or high dose HCTZ plus a low or high dose of a step II drug (propranolol, clonidine or reserpine). After 6 months of treatment that controlled BP, dosages were reduced in two-thirds of the patients. In those patients receiving low dose HCTZ and randomized to dose reduction, antihypertensive drugs were completely discontinued. Although approximately half of these patients remained normotensive for the first 6 months, a significantly greater proportion had elevation of BP compared to the control group, which continued to receive treatment (p less than 0.0001). In the high dose HCTZ drug group, the proportion of patients remaining normotensive did not differ among those stepped down to low dose HCTZ and the fully treated control group. While not achieving significance the trend was similar with the step II regimens. Although some patients remained normotensive after discontinuation of step II drugs, a greater proportion returned to elevated BP than when step II dosage was unchanged. Therefore, while stopping therapy may be effective in some patients, a decreased dosage is significantly more effective as a method for maintaining an antihypertensive effect. Decreasing drug dosages offers the dual benefit of minimizing side effects and reducing drug costs.

Antihypertensive Agents↗
PubMed1989

Functionally different HTLV I-infected T cell lines with the same phenotype derived from a patient with melanoma.

Two autologous T cell lines infected with HTLV I are described. T cells from a patient with malignant melanoma were infected with HTLV I by co-culture with a HTLV I-producing T cell line, SLB I. Both T cell lines express identical phenotype (CD3+, CD4+, 4B4+, 2H4-) but they demonstrate marked differences in growth characteristics and function. One of these two lines, referred to as TFTx, established from the autologous tumor activated peripheral blood lymphocytes (PBL), grows in culture without any exogenous interleukin-2 (IL-2), secretes no detectable amount of IL-2 or gamma interferon (IFN) or tumor necrosis factor (TNF) alpha or beta. The other line (TFATx), established from a co-culture between the autologous PBL, lethally irradiated TFTx and the autologous melanoma cells TF-M, is IL-2-dependent for growth, secretes IFN gamma and TNF alpha and beta. TFTx exerts profound suppression of generation of cytotoxicity in the autologous PBL in co-culture with the autologous melanoma cells TF-M. In contrast, the TFATx enhances the cytotoxic response in similar co-culture. In addition to suppression of cytotoxic response, supernatant from TFTx suppresses the lectin-activated proliferation of PBL. In 4-h chromium release microcytotoxicity assays, neither line exhibits conventional characteristics of cytotoxic cells. Thus, phenotypically identical HTLV I-infected CD4+ T cell lines derived from the same individual exhibit opposite regulatory functions.

CD4-Positive T-Lymphocytes↗
PubMed1989

In vivo measurements of vascular oxygen tension in tumors using MRI of a fluorinated blood substitute.

The authors measured the level of blood oxygenation in vivo in a series of rats with implanted mammary adenocarcinoma. The technique used was 19F magnetic resonance imaging of a perfluorochemical blood substitute. The method is based on the effect of oxygen on the T1 relaxation time of the fluorochemical and allows the determination of mean vascular PO2 independent of the blood volume in the tissue. The PO2 levels in the liver, lung, and spleen also were determined and were consistent with previously reported results. When the rats breathed air, the tumor PO2 levels were somewhat lower than in the other organs and were in a range typical of venous blood. When the rat was given 100% oxygen to breathe, the tumor PO2 levels increased far less than the PO2 levels of the other organs. This may indicate a greatly diminished blood flow to this particular tumor.

Adenocarcinoma↗
PubMed1988

Alteration by perfluorodecalin of hepatic metabolism and excretion of phenobarbital.

The bile duct was cannulated in rats that had been infused intravenously with an emulsion of perfluorodecalin at intervals from 2 to 34 weeks earlier. After injection of [14C]phenobarbital, urine and bile were collected during the next 24 hr and were analyzed for phenobarbital and its metabolites. There was a decrease in the biliary excretion of phenobarbital and its metabolites for several weeks after infusion of perfluorodecalin, but conjugation of the metabolites was not decreased. The reduced excretion returned to normal after about 20 weeks.

Animals↗
PubMed1988

Imaging pattern of previously in vitro sensitized and interleukin-2 expanded autologous lymphocytes in human cancer.

In vivo patterns of lymphocytes sensitized against autologous tumor (in vitro) were studied in seven patients with metastatic cancer as a potential candidate for an alternative method of radioimmunodetection and adoptive immunocytotherapy. Peripheral blood lymphocytes (PBL) were either activated in Interleukin-2 (IL-2) [lymphokine activated killer (LAK) cells] or sensitized against autologous tumor cells by in vitro co-culture (IVC) and expanded in IL-2 (educated cells); both were then labelled with 111In. Labelled autologous cells (1 x 10(7)-5 x 10(8)) were administered to patients and biodistribution studied by imaging under a gamma camera at various time intervals. In 4/7 cases, imaging with the educated cells showed concentrations of radioactivity at sites that correlated positively with clinically detectable metastatic tumor. By contrast, only one instance of positive uptake was seen with the LAK cells. Other than slight fever in three cases, infusions of labelled PBL were well tolerated. Educated lymphocytes were cytotoxic against autologous tumor cells and the cytotoxic reactivities of the educated cells were maintained in continuous culture in IL-2 for 4-6 weeks. Evidence of accumulation of radiolabelled educated autologous cells at a significantly higher frequency than that of the LAK cells suggests that in vitro expanded educated PBL might be better candidates for radioimmunodetection of human cancer, and continuous cultures of such educated autologous PBL might be sources for repeated administration of these effector cells.

Adult↗
PubMed1988

Utilization of tumour-sensitized ('educated') and radiolabelled lymphocytes for tumour localization.

Upon coculture of peripheral blood lymphocytes (PBL) in the presence of irradiated autologous tumour cells, the PBL can be sensitized to the tumour (or perhaps more correctly resensitized), as shown by in vitro cytotoxic properties. The cells can be proliferated in the presence of interleukin-2, radiolabelled with 111In and injected back into the cell donor. Using this technique, tumour deposits were localized in five out of seven patients. Possible techniques for increasing the specificity of this form of adoptive immunocytotherapy are pointed out.

Antigens, Neoplasm↗