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F Triebel

Publications and source records attributed to F Triebel.

At least 37 records · Page 2Linked to original sources
PubMed1990

Immunotherapy with lymphokine-activated natural killer cells and recombinant interleukin-2: a feasibility trial in metastatic renal cell carcinoma.

Clinical immunotherapy trials have been performed recently where ex vivo interleukin-2 (IL-2)-activated peripheral blood mononuclear cells (i.e., the "LAK" cells) have been transfused in addition to IL-2 infusions. In such protocols, patients have received highly heterogeneous cell suspensions and the nature of the effector cells that may have contributed to tumor regression has remained unclear. In certain animal models, it has appeared that natural killer lymphocytes were the effector cell type responsible for tumor regression. To test whether NK cells could eventually be relevant for the treatment of human tumors, we have performed a feasibility trial where purified lymphokine-activated natural killer (LANAK) cells have been prepared and transfused to a limited series of renal cell carcinoma patients receiving IL-2 (continuous infusions at 3 x 10(6) U/m2/day). Natural killer lymphocytes (1-2 x 10(6] were purified from peripheral blood mononuclear cells and expanded during 4-5 weeks in the presence of IL-2 on microtiter plates containing feeder layers cells. In vitro, the resulting LANAK cell suspensions were 100 times (range of 2 to 10(3] more efficient against Daudi target cells than their autologous LAK counterparts. Twelve patients were included; 9 received the two planned courses of treatment with LANAK cells and IL-2. Overall toxicity was relatively moderate. Besides occasional chills, there were no apparent secondary effects due to cell infusions. The mean number of LANAK cells transfused per patients was 45.1 x 10(9), ranging from 7 to 125 x 10(9). The biodistribution of LANAK cells was similar to that reported previously for LAK cells with no preferential localization to tumor sites. We conclude from this study that using well-defined populations of effector lymphocytes is a feasible cellular therapy approach that may lead to improved understanding and efficacy of the novel immunotherapy methods.

Adult↗
PubMed1989

cDNA cloning of functional T cell receptor gamma/delta chains expressed in human peripheral blood lymphocytes.

We have identified in earlier studies two V delta rearrangements corresponding to a 4.5-kb Eco RI fragment detected with a V delta1 probe and to a 7-kb Eco RI band detected with a V delta2 probe. These rearrangements have been found in two human T cell clones, F6C7 and G6, displaying surface phenotypes unfrequent in human peripheral blood, namely Ti gamma A+ BB3- (F6C7) and Ti gamma A- BB3+ (G6). Herein, we report the sequences of the functional transcripts encoded by these rearranged genes and show that the 4.5- and the 7-kb Eco RI fragments correspond to V1/D3/J delta 3 and to V2/D3/J delta 3 recombinations, respectively. In addition, we have sequenced the V2/D3/J1/C delta transcripts expressed in two clones, AB12 and VTC, which have a Ti gamma A+ BB3+ surface phenotype corresponding to that of most gamma/delta peripheral lymphocytes. Analyses of the delta transcripts expressed by these four cells further strengthen the hypothesis that anti-BB3 and anti-delta-TCS-1 monoclonal antibodies recognize a V delta 2- and a V1/(D)/J delta 1-encoded epitope, respectively. Sequence of the gamma transcripts expressed by AB12 and F6C7 cells shows that they encode a V9/JP/C gamma 1 chain. Finally, we confirm that non-combinatorial diversity in the gamma and delta proteins is generated by both junctional flexibility and N-region addition without any somatic mutation.

Amino Acid Sequence↗
PubMed1989

Subpopulations of human peripheral T gamma delta lymphocytes.

In the search for the genes encoding the alpha and beta chains of the T-cell receptor, Tonegawa et al. discovered a third class of rearranging T-cell specific genes. This finding led them to postulate the existence of additional forms of T-cell receptors. In this article, Frédéric Tribel and Thierry Hercend briefly discuss recent results, which may help in the delineation of human peripheral blood gamma delta+ subsets based on the molecular structure of this receptor.

Antibodies, Monoclonal↗
PubMed1989

The T-cell receptor V delta genes predominantly used by human peripheral gamma/delta+ T lymphocytes are not rearranged in CD3- natural killer cells.

We have analyzed, in 19 CD3- natural killer cell clones, the genomic organization of the T-cell receptor delta locus with two distinct V delta probes, V delta 1 and V delta 2. These two V delta genes code for surface proteins expressed in more than 90% of peripheral blood T-cell receptor gamma/delta+ lymphocytes, as shown by double color immunofluorescence analysis with anti-TCR delta 1, anti-BB3, and anti-delta TCS1 monoclonal antibodies. The V delta 1 and V delta 2 genes were found to be in germline position in all these clones, which are distinct phenotypically and represent a variety of the corresponding peripheral natural killer cell populations. We also studied in these cloned cell lines the transcriptional activity of the T-cell receptor delta locus with a C delta probe: short transcripts (1.7 and 0.8 kb) were found exclusively. These experiments further suggest that CD3- natural killer peripheral cells are likely to constitute a unique lineage distinct from T lymphocytes.

Antibodies, Monoclonal↗
PubMed1989

T cell receptor gamma/delta+ lymphocyte subsets during HIV infection.

The gamma/delta T cell receptor is expressed on 1-15% of normal human peripheral blood lymphocytes (PBL). This subpopulation is recognized by anti-TcR-delta 1 MoAb which is functionally defined as a pan-delta MoAb. Two other antibodies, anti-Ti-gamma A and anti-delta-TcS1 are directed at variable determinants of either the gamma or the delta chain, respectively. In normal individuals anti-Ti-gamma A characterizes two thirds of the TcR-delta 1+ subpopulation whereas anti-delta TcS1 reacts with most of the delta-TcR1+, Ti-gamma A- cells. In the present study, we have used these three MoAbs to characterize the TcR gamma/delta+ peripheral lymphocytes during HIV infection. Fifty patients at three distinct clinical stages (SPC/PGL, ARC, AIDS) of the infection have been studied. The Ti-gamma A+ subset in the whole group accounted for 3.45% of PBL and did not differ from controls; it was also unchanged when the three groups were analysed separately. The Ti-gamma A+ circulating cells were in a resting state as assessed by the absence of surface-expressed activation markers. In contrast, in some patients the proportion of circulating TcR-delta 1+, Ti-gamma A-, delta TcS1+ cells was increased (4.75%) leading to an inversion of the Ti-gamma A/delta-TcS1 ratio. Altogether, those data suggest a conservation of the Ti-gamma A+ subset during HIV infection, contrasting with an increase of the delta-TcS1+, Ti-gamma A- fraction in some cases.

AIDS-Related Complex↗
PubMed1988

Characterization of human peripheral lymphocytes expressing the CD3-gamma/delta complex with anti-receptor monoclonal antibodies.

Three mAb, anti-Ti gamma A, anti-TCR delta 1, and anti-delta TCS1, have been developed against the CD3-associated gamma/delta molecular complex. One of this antibody anti-Ti gamma A is specific for an epitope encoded by the V9 gamma-gene. The two others react with the delta-chain but their fine epitopic specificity has not been characterized previously. In the present study, we have compared the surface expression of these three antigenic determinants on 27 cloned and 5 polyclonal CD3+ TCR gamma/delta + cell lines derived from human peripheral blood of 13 distinct individuals. It was found that all CD3+ TCR alpha/beta- clones and polyclonal cell lines tested were recognized by anti-TCR delta 1. In contrast, only a fraction of both clones and cell lines reacted with either anti-Ti gamma A or anti-delta TCS1 mAb. In fact reactivity of the latter reagents was found to be mutually exclusive on the cell panel. Northern blot analysis of RNA extracted from a series representative clones showed a positive correlation between the surface expression of the delta TCS1 epitope and the transcription of the V-delta gene isolated from the IDP2 cell line. These data support the view that anti-TCR delta 1 can be used to positively define the entire TCR gamma/delta+ fraction. Moreover, the reciprocal reactivity of anti-delta TCS1 and anti-Ti gamma A on cultured cell lines suggests that these reagents should delineate in human peripheral blood distinct, essentially non-overlapping, subsets. Taken together, the present results indicate that the complementary use of these three antibodies will be helpful to further characterize the TCR gamma/delta + peripheral lymphocyte fraction.

Adult↗
PubMed1988

Identification of a CD2- CD3+ T cell receptor-gamma+ peripheral blood lymphocyte subpopulation.

We have identified, in a healthy individual, a sub-population of human peripheral lymphocytes which surface express a CD3-TCR-gamma complex recognized by anti-Ti gamma A mAb, while being unreactive with a phycoerythrin-conjugated anti-CD2 antibody with T11/1 specificity. Further immunofluorescence analyses performed on uncultured cells indicated that such a putative CD2-CD3+ phenotype was restricted to a fraction of those T lymphocytes which carry a surface receptor of the "second family" (gamma/delta). The actual lack of CD2 expression was confirmed by a subsequent series of cloning experiments which showed that none of the three well characterized CD2 epitopic clusters, namely T11/1, T11/2, and T11/3, were detectable on the surface of the relevant cells. The cultured CD2-, CD3+/TCR gamma + lymphocytes were found to display, as well as their CD2+ counterparts, both non-MHC-restricted cytotoxic function and proliferative responses induced via the gamma receptor complex. In contrast, the proliferative capacity of the CD2-, CD3+/TCR-gamma + cells observed in a culture system designed for in vitro expansion of lymphocytes with undefined specificity was extremely limited. This may relate to an impaired interaction of the CD2- cloned lymphocytes with lymphocyte function-associated (LFA)3+ irradiated cells present in the feeder layer. Further characterization of such minor CD2- T lymphocytes subsets may help to better understand the biologic relevance of the CD2/LFA3 pathway of cell-cell interaction.

Adult↗
PubMed1988

CD3/Ti gamma A: a functional gamma-receptor complex expressed on human peripheral lymphocytes.

We have recently developed a mAb designated anti-Ti gamma A, which was found to immunoprecipitate from the well characterized CD3+ TCR alpha/beta- F6C7 fetal clone a CD3-associated disulfide-linked gamma-glycoprotein. This antibody recognizes approximately 3% of adult peripheral lymphocytes and delineates a CD2+ CD3+ TCR alpha/beta- CD4- NKH1- subset where expression of CD8 appears to vary widely from one individual to another. In the present study, we have used anti-Ti gamma A mAb to assess whether gamma-chains expressed on these adult lymphocytes are used as functional R. The two activities which have been associated thus far with TCR gamma+ cells, that is, IL-2-dependent proliferation and non-MHC-restricted cytotoxicity, were investigated here by using either resting or activated Ti gamma A+ lymphocytes. On the resting state, these cells (which appear as a very homogeneous population of granular lymphocytes) mediate little if any NK activity that could not be augmented by anti-Ti gamma A mAb. In contrast, after initial stimulation by PHA plus rIL-2 and subsequent culture in the presence of IL-2, activated Ti gamma A+ lymphocytes were strongly lytic against a series of conventional NK target cell lines. This cytotoxic function was either blocked or enhanced by anti-Ti gamma A mAb, depending upon experimental conditions. With respect to proliferation, it was possible to induce responses of resting Ti gamma A+ lymphocytes with antibody-coated CNBr beads only in the presence of exogenous IL-2, whereas, in culture, the same cells proliferated directly and secreted IL-2 after treatment by anti-Ti gamma A beads. Taken together, these data demonstrate that a major subset of circulating CD3+ TCR alpha/beta- lymphocytes use protein products of T cell gamma rearranging genes as functional R structures.

Animals↗
PubMed1988

A unique V-J-C-rearranged gene encodes a gamma protein expressed on the majority of CD3+ T cell receptor-alpha/beta- circulating lymphocytes.

We have recently described an mAb, anti-Ti gamma A, that recognizes an antigenic determinant carried by a TCR gamma chain. This antibody binds to approximately 3% of human PBLs and delineates a CD2+, CD3+, TCR-alpha/beta-, CD4-, CD8+/-, CD5+, NKH1-, and HLA class II- subset. The present study was designed to identify the gene encoding the Ti gamma A epitope. A first analysis was carried out on a previously characterized TCR gamma + fetal-cloned cell line termed F6C7. It was found that F6C7 cells have one gamma rearrangement on each chromosome: one joins V gamma 3 to J gamma 1, and the second joins V gamma 9 to J gamma P. Because only the latter allele appeared to be transcribed in the F6C7 lymphocytes, these data strongly suggested that anti-Ti gamma A mAb is specific for either a V gamma 9 or a V gamma 9-J gamma P-encoded peptide. To confirm this point, we studied an additional series of 13 randomly selected Ti gamma A+ cloned cells derived from peripheral blood of three distinct adult individuals. Each one of these lymphocytes was shown to both possess and transcribe a V gamma 9-J gamma P-C gamma 1-rearranged gene. It is therefore concluded that a predominant subpopulation of CD3+ TCR-alpha/beta- human circulating T lymphocytes (namely, the subset defined by anti-Ti gamma A mAb) surface expresses a gamma protein with a limited potential of variability from one cell to another.

Adult↗
PubMed1988

Evidence for expression of two distinct T cell receptor beta-chain transcripts in a human diphtheria toxoid-specific T cell clone.

We have cloned and sequenced the human T cell receptor alpha- and beta-chains cDNA present in a lambda gt10 library derived from a human CD4+ diphtheria toxoid-specific T cell clone, PH28. Two 1.3-kb beta-transcripts within frame V, D, J joining were found. These two functional beta-transcripts use two members of different V beta-families, V beta 3 and V beta 4, one joined to D beta 1-1, J beta 1-1, C beta 1, the other joined to D beta 1-1, J beta 2-1, C beta 2. Moreover, we have cloned the two different V beta germ-line counterparts whose sequences confirm that these two V beta are not pseudogenes. Analysis of T cell receptor beta and alpha rearrangements in PH28 showed that a single rearrangement on each chromosome could be assigned either at the J beta or the J gamma loci. These results strongly suggest an absence of allelic exclusion for 1.3-kb mRNA beta-transcripts in a human antigen-specific T cell clone.

Amino Acid Sequence↗
PubMed1988

Cloned CD3+ TcR alpha/beta- Ti gamma A- peripheral blood lymphocytes compared to the Ti gamma A+ counterparts: structural differences of the gamma/delta receptor and functional heterogeneity.

We have assessed the organization of T cell gamma rearranging genes (TRG) in circulating TcR gamma/delta+ lymphocytes which do not express V gamma 9-encoded Ti gamma A+ gamma chain. Following purification of the minor TcR gamma/delta+ Ti gamma A- fraction, cloned cell lines were developed from peripheral blood of 5 individuals. Out of the 26 clones studied, only 3 TcR gamma/delta+ Ti gamma A- cells were found to express a disulfide-linked C1-encoded gamma chain. The remaining 23 Ti gamma A- clones with a C2-encoded nondisulfide-linked receptor were found to display rearrangements of various V genes to J2 segments on both chromosomes; there was no predominance of a unique rearrangement even though the TRG-V3 and -V4 genes belonging to subgroup I were frequently employed. Together, these findings further strengthen the hypothesis that lymphocytes with a C gamma 1 encoded chain are produced earlier in T cell ontogeny than the C gamma 2 counterparts. The "non-major histocompatibility complex (MHC) requiring" (i.e., "natural killer-like") cytotoxicity mediated by many TcR gamma/delta+ Ti gamma A- cells appeared to be very low as compared to that of Ti gamma A+ clones. Yet, treatment by the OKT3 monoclonal antibody revealed a strong lytic potential in the Ti gamma A- lymphocytes with little, if any, natural killer-like activity. Thus, with respect to the latter function, a substantial heterogeneity is found in cells expressing distinct gamma chains. In an attempt to characterize undefined specificities of Ti gamma A- lymphocytes, they were screened against a panel of Epstein-Barr virus-transformed B cell lines homozygous for HLA-DR1 to DR10 determinants; one of the clones was found to recognize DR7. In light of reports from other groups describing class I-related specificities, it is apparent that TcR gamma/delta+ lymphocytes are able, like the TcR alpha/beta+, to recognize and kill target cells through either an MHC-dependent (with involvement of either class I or class II gene products) or a non-MHC-requiring pathway.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1988

A novel human V delta gene expressed predominantly in the Ti gamma A fraction of gamma/delta+ peripheral lymphocytes.

We have characterized a functional T cell receptor (TcR) delta transcript in a Ti gamma A+ human cloned cell line derived from peripheral blood. This cDNA includes a novel V gene (V-AB12), whose expression was initially studied in a series of TcR gamma/delta+ clones. Nine Ti gamma A+ clones derived independently from distinct donors have been tested: each of them was found to possess a unique V-AB12/J-IDP2 5.5-kb Eco RI rearrangement, which was constantly transcribed. Surface expression of the protein encoded by this unique rearranged gene was demonstrated by immunoprecipitations performed on three Ti gamma A+ polyclonal cell lines using a specific rabbit heteroantiserum. Further analysis strongly suggested that a monoclonal antibody (mAb), designated anti-BB3, detects a V-AB12-encoded antigenic determinant on the cell surface. Double-color immunofluorescence analysis of peripheral blood lymphocytes from ten donors indicated that most BB3+ cells are recognized by anti-Ti gamma A mAb. In previous studies, we have shown that a majority of TcR gamma/delta+ peripheral T cells expresses a gamma chain including V9 (Ti gamma A) and most frequently JP-encoded peptides. Given the present results on the delta chain, it can be concluded that, in many individuals, a predominant fraction (V gamma 9+/V-AB12+) of circulating CD3+ TcR alpha/beta- T lymphocytes expresses a receptor with little, if any, combinatorial diversity.

Amino Acid Sequence↗
PubMed1988

Prominent expansion of circulating lymphocytes bearing gamma T-cell receptors, with preferential expression of variable gamma genes after allogeneic bone marrow transplantation.

The presence of two distinct T-cell receptors (TCR) alpha/beta dimers or gamma/delta dimers, was systematically analyzed in peripheral blood lymphocytes form 26 recipients of allogeneic bone marrow transplants for leukemia. When using monoclonal antibody WT31, which recognizes a common epitope on the alpha/beta heterodimer, the expansion of peripheral CD3+, WT31- cells to 40% of the PBLSs was detected in two patients. In patient 2, the presence of circulating TCR gamma-bearing cells was directly demonstrated with monoclonal antibody Ti gamma A directed against the V gamma 9 J gamma p gene products. From CD3, WT31- clones derived from patients 1 and 2, sequential immunoprecipitations were performed with anti-CD3 and anti-C gamma to determine the CD3-associated structure. Molecular weights of gamma subunits were different in both patients, thus indicating structural heterogeneity. The ability of TCR gamma clones to proliferate when stimulated with anti-CD3 beads was observed for clones from patient 2, whereas this response required exogenous interleukin-2 for clones from patient 1. We have already shown that the TCR gamma cells from patient 1 might have played a role in the immunodeficient state. Similar conclusions cannot be drawn from patient 2. Southern blot analysis of total PBL gamma cell lines and clones indicated that this major circulating subset of TCR gamma cells retained a TCR beta gene in germline configuration and preferentially expressed a single V gamma gene, V gamma 5 for patient 1 and V gamma 9 for patient 2.

Antibodies, Monoclonal↗
PubMed1988

[Principles of treatment with cells called "LAK" cells].

A novel approach for immunotherapy of cancer is presently under investigation. This treatment initially developed by Steven Rosenberg and colleagues is based on both the transfusion of autologous lymphocytes preactivated in vitro using interleukin 2 and the simultaneous infusion of the lymphokine in vivo. The two major limiting factors for these new protocols are, on the one hand, the heavy infrastructure necessary for in vitro cell treatment, and, on the other hand, the dose-dependent toxicity of IL2 infusions. Results of clinical trials are still preliminary; they suggest that the therapy may be of interest in melanomas and renal cell carcinomas. However, only a minority of patients with these relatively susceptible tumors display substantial responses. Thus, the protocols need to be improved which makes it critical to understand the biological mechanisms underlying tumor regression in vivo. The dominant working hypothesis is that IL2 enhances firstly in vitro and then in vivo the activity of certain lymphocytes able to destroy tumor cells via a direct cytotoxic effect. This view supported by murine experimental models remains to be demonstrated in the human. One way of testing it, is to infuse highly purified fractions of killer lymphocytes instead of the whole peripheral blood suspensions that are used presently. We are attempting to develop this approach and a trial is presently beginning at the Gustave-Roussy Institute in a series of patients with renal cell carcinoma.

Humans↗
PubMed1987

A novel subset of human lymphocytes with a T cell receptor-gamma complex.

We have previously characterized a CD3+ T cell receptor (TCR) alpha/beta- human fetal cloned cell line, termed F6C7, which surface-expresses a CD3-associated gamma chain identified by anti-NKFi, an mAb with a restricted clonotypic reactivity. Here, we have produced an additional antibody, anti-Ti-gamma A, which recognizes a public epitope of the gamma molecule defined by anti-NKFi. Ti-gamma A is present on approximately 3% of circulating lymphocytes with a wide range (1-15%) among 30 healthy individuals tested. Two-color immunofluorescence experiments performed with anti-Ti-gamma A and BMA 031 mAb (a reagent specific for the TCR-alpha/beta receptor) showed that surface expression of Ti-alpha/beta and Ti-gamma A is mutually exclusive. Moreover, it was found that most Ti-gamma A+ cells are CD2+, CD3+, CD4-, CD5+, NKH1-, HLA class II-negative. In contrast, the expression of the CD8 molecule on these T lymphocytes appears to be variable from one individual to another. Finally, we found that Ti-gamma A+ cells represent a majority of peripheral lymphocytes that express CD3 proteins but not the TCR-alpha/beta heterodimer. The delineation of this unique lymphocyte subset should help further studies on the biology of cells with a CD3-associated gamma complex.

Animals↗
PubMed1987

Cloned human CD3- lymphocytes with natural killer-like activity do not express nor rearrange T cell receptor gamma genes.

Here we report the characterization of T cell receptor (TCR) gene activation in 14 CD3- cloned lymphocytes with natural killer-like activity from different origins. No transcription of either alpha or beta or gamma genes is detected in any of these clones. All J beta, C beta clusters are in germ-line configuration. The 5 presently described J gamma loci (J gamma P1, J gamma P, J gamma 1, J gamma P2, J gamma 2) are also in germ-line configuration on each chromosome. These results indicate that several distinct populations of CD3- cloned NK cells do not use gamma gene products as a recognition structure. Perhaps more importantly, these cells do not appear to be engaged in the earliest presently known stage of T lymphocyte differentiation, namely rearrangement at one of the J gamma loci.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1987

Monoclonal B-cell response to diphtheria toxoid: evidence for cross-reactive epitopes.

Our previous studies on the human specific B- and T-cell responses against diphtheria toxoid (DT) had shown that the B- and T-cell antigenic determinants were mostly assembled topographic sites with large intra-molecular cross-reactivities. In order to characterize further the B-cell responses against DT, and to investigate these cross-reactivities, we have produced 54 murine monoclonal antibodies (moAbs) against the native DT. Determination of their antigenic specificity showed that 25 moAbs recognized conformational determinants on the native DT, 20 moAbs reacted against the A fragment (DTA) of the toxin, and nine moAbs reacted with at least three distinct highly purified CNBr peptides of the B fragment (DTB); some of them simultaneously recognized two or three purified CNBr peptides of DTB. As shown by cross-inhibition studies, the epitopes cross-reacting with those moAbs were distinct. Previously described sequence data indicated that these epitopes were not induced by repetitive amino-acid sequences. Finally, a cross-reactive idiotype was shared by moAbs specific for the CB1 and the CB3 peptides of DTB. Altogether, these data indicate that anti-DT moAbs are mostly directed against conformational determinants, and may cross-react with several DTB CNBr peptides.

Animals↗