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F Jotereau

Publications and source records attributed to F Jotereau.

At least 37 records · Page 2Linked to original sources
PubMed1997

Human monocyte-derived macrophages and dendritic cells are comparably effective in vitro in presenting HLA class I-restricted exogenous peptides.

Recent experimental data have shown that mice could be immunized efficiently, in particular against cancer, by the injection of antigen-loaded dendritic cells (DC) or macrophages (MPH). In the present work, these two antigen-presenting cells (APC) were prepared in humans from circulating mononuclear cells (MNC). MPH were obtained from MNC that were cultured in hydrophobic plastic bags and purified by elutriation. DC were from the culture of adherent elutriation-purified monocytes in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4). The two APC were prepared in parallel from the same donors and their phenotype and antigen-presenting capacity were compared. DC differed from MPH by a higher expression of HLA-DR and CD23 and a lower expression of CD14, CD64 and of adhesion molecules. DC and MPH were comparably effective in (a) enhancing the mitotic response of autologous lymphocytes to immobilized anti-CD3 (accessory function); (b) presenting melanoma peptides to specific cytotoxic T lymphocyte (CTL) clones; and (c) stimulating the generation of CTL directed against a myxovirus influenza peptide. However, DC were more effective than MPH in inducing the mitotic response of allogeneic peripheral blood leucocytes (PBL), possibly because of their higher expression of HLA class II molecules. In conclusion, DC and MPH prepared from blood MNC did not differ substantially in their ability to activate HLA class I-restricted T-cell responses by exogenous peptide presentation.

Antigen Presentation↗
PubMed1996

Suboptimal activation of melanoma infiltrating lymphocytes (TIL) due to low avidity of TCR/MHC-tumor peptide interactions.

Coculture of melanoma cells and T cell clones derived from tumor-infiltrating lymphocytes (TIL) generally results in lysis of the antigen-bearing tumor cells but to inefficient proliferation and IL-2 secretion by responder T cells. This suboptimal activation is classically explained by an inability of tumor cells to provide costimulatory signals. Here we analyzed the responses to synthetic peptides of HLA-A2.1-restricted CTL clones specific for melanoma antigens MART-1 and NA17-A. We showed that peptide concentrations ranging from 1 pM to 10 nM efficiently sensitized the peptide transporter-deficient T2 cells to lysis. T2 cells pulsed with melanoma peptides also induced TIL proliferation and detectable secretion of IL-2, IFN-gamma and GM-CSF, but only for peptide concentrations 10- to 10,000-fold higher than those required for lysis. Hence this suggests that partial triggering of TIL clones by melanoma cells could be due to expression of appropriate MHC-peptide complexes at subthreshold levels. In support of this, we showed that melanoma cells, unable to trigger IL-2 secretion, developed this ability when incubated with the appropriate peptide. These results indicate that the level of antigens expressed on melanoma tumors critically affects TIL activation status and thus, the efficiency of specific immune reactions mediated by these cells.

Antigens, Neoplasm↗
PubMed1996

A peptide recognized by human cytolytic T lymphocytes on HLA-A2 melanomas is encoded by an intron sequence of the N-acetylglucosaminyltransferase V gene.

A cytolytic T lymphocyte (CTL) clone that lyses many HLA-A2 melanomas was derived from a population of tumor-infiltrating lymphocytes of an HLA-A2 melanoma patient. The gene coding for the antigen recognized by this CTL was identified by transfection of a cDNA library. It is the gene which has been reported to code for N-acetylglucosaminyltransferase V (GnT-V). Remarkably, the antigenic peptide recognized by the CTL is encoded by a sequence located in an intron. In contrast to the fully spliced GnT-V mRNA, which was found in a wide range of normal and tumoral tissues, the mRNA containing the intron region coding for the antigen was not found at a significant level in normal tissues. This mRNA was observed to be present in about 50% of melanomas. Our results suggest that a promoter located near the end of the relevant intron is activated in melanoma cells, resulting in the production of an mRNA coding for the antigen.

Amino Acid Sequence↗
PubMed1995

Selective lysis of autologous tumor cells by recurrent gamma delta tumor-infiltrating lymphocytes from renal carcinoma.

We show here that tumor infiltrating lymphocytes (TIL) derived from three renal carcinoma (RC) tumors, which developed in the same patient over a 3-yr period, were systematically enriched in gamma delta + T cells (27-74%) after short term in vitro culture. Analysis of the repertoire of gamma delta + TIL and PBL from this patient, revealed the predominant expression of structurally diverse V delta 1 gamma delta TCR by TIL from the three tumors, contrasting with the classically dominant use of V delta 2 TCR by PBL. Functional analysis further showed that, independently of the V gamma genes expressed, all the V delta 1+ TIL clones exhibited a lytic activity apparently restricted to RC lines, while V gamma 9+V delta 2+ clones (either PBL- or TIL-derived) had a broad killing activity. Surprisingly most V delta 1+ CTL clones lysed several allogeneic, but not the autologous, RC lines. Only one V gamma 3+V delta 1+ TIL clone, identified by its specific variable TCR gene sequence, consistently killed autologous tumor cells, apparently via TCR-mediated MHC-unrestricted recognition. This clone also lysed two allogeneic RC lines out of four tested but did not kill 30 non-RC lines, except for one breast carcinoma line. Significantly, this clone was found in recurrent fashion in all three tumors analyzed, including a metastasis. The high frequency of V delta 1 expressing RC-reactive gamma delta cells among TIL from this patient suggests that this gamma delta subset was selectively trapped and/or preferentially induced to proliferate in the autologous tumors. The recurrence of a single V gamma 3+V delta 1+ gamma delta clone, reacting with autologous tumor cells, inside three tumors of different localizations additionally suggests that, for this clone, intratumor selection and/or proliferation was due to TCR-mediated recognition of a non-MHC-restricted RC-specific Ag.

Adolescent↗
PubMed1995

HLA class II-restricted recognition of common tumor epitopes on human melanoma cells by CD4+ melanoma-infiltrating lymphocytes.

CD4+ T cell clones derived from lymphocytes infiltrating four human melanomas specifically recognized melanoma-derived tumor epitopes as shown by secretion of tumor necrosis factor (TNF) in vitro upon interaction with autologous melanoma cells, whereas they did not recognize HLA class II-expressing autologous lymphoblasts or HLA class II mismatched allogeneic melanoma cells. Specificity was further established by demonstrating that TNF responses to tumor cells were inhibited by HLA-DR or HLA-DQ monoclonal antibodies. Most of these clones cross-reacted with allogeneic melanoma cells expressing a potentially restricting HLA allele or a structurally similar one. These data show that shared epitopes of human melanoma cells presented on HLA class II molecules are frequently recognized by autologous CD4+ T lymphocytes.

Alleles↗
PubMed1995

T cell activation by antigens on human melanoma cells--co-stimulation by B7-1 is neither sufficient nor necessary to stimulate IL-2 secretion by melanoma-specific T cell clones in vitro.

B7-1 expression, induced by transfection in poorly immunogenic murine tumours, was shown to elicit a T cell-mediated rejection of these tumours and further active immunity against the non-transfected tumour. We therefore asked to what level similarly induced expression of B7 on human melanoma cells would affect the antigen-dependent responses of tumour-specific T cell clones in vitro. Data presented show that B7-1 expression by melanoma lines: (i) significantly induced, or improved, an IL-2-dependent proliferative response of such clones to the antigen; (ii) increased the amount of IL-2 produced by two clones in response to the parental non-transfected tumour cells; and (iii) increased the TNF responses of all the CD4+ clones. However, despite these clear co-stimulatory effects on antigen-induced responses of all T cell clones, which demonstrated an effective interaction of the B7-1 transfected molecule with one or the other of its counter-receptors expressed on T cell clones, B7 co-stimulation did not correct the defect of IL-2 secretion exhibited by many of these clones in response to in vitro antigen presentation by melanoma cells. We further show that defective IL-2 secretion in response to melanoma antigens was not due to a T cell clone refractoriness induced by the culture, since one of these clones could be induced to secrete IL-2 by an antigen-expressing melanoma line, upon increased lymphocyte function associated antigen-3 expression induced by gene transfection. Together these data suggest that defective IL-2 secretion by many tumour-infiltrating lymphocytes clones in response to antigen presentation by melanoma cells in vitro is not exclusively due to the inability of these cells to provide an appropriate co-stimulation through the B7-1 molecule.

Animals↗
PubMed1994

Oligoclonality of tumor-infiltrating lymphocytes from human melanomas.

A PCR-based method that determines VDJ junction size patterns in 24 human TCR V beta subfamilies was used to analyze T cells infiltrating sequential malignant melanoma biopsies for the presence of clonal expansions. Infiltrating T cell populations were found to present clonal expansions over a more or less complex polyclonal background. Two clones from a single patient were sequenced and detected in three different tumor sites (skin biopsies), whereas only one of them was also present in peripheral blood. Biopsies from this patient did not show major repertoire changes during in vivo IL-2 treatment. In contrast, in biopsies from a second patient, the expression of all the detected V beta subfamilies was increased and a larger number of clones expanded, probably as a result of therapy. A similar evolution was found among infiltrating T cells cultured in vitro from a third patient for several weeks in the presence of IL-2, where the largely polyclonal repertoire of fresh T cells (from invaded lymph nodes) was dramatically reduced to mainly clonal expansions in all V beta subfamilies detected. The high resolution method used here enables a rapid, comprehensive, qualitative, and semiquantitative description of the T cell repertoire of heterogeneous cell populations. Its use in conjunction with a functional analysis of clones detected within these populations should provide a better understanding of the evolution of the T cell repertoire among tumor-infiltrating lymphocytes during the progression of the disease and as a response to immunotherapy.

Base Sequence↗
PubMed1994

Defective lymphokine production by most CD8+ and CD4+ tumor-specific T cell clones derived from human melanoma-infiltrating lymphocytes in response to autologous tumor cells in vitro.

Human melanomas are infiltrated by tumor-reactive T lymphocytes. However, the ability of these cells to elicit a specific anti-tumor response in vivo remains to be established. Because lymphokine production is critical for T cell functions, we have analyzed the capacity of melanoma-specific tumor-infiltrating lymphocyte (TIL) clones to produce major lymphokines: interleukin-2 (IL-2), interferon-gamma (IFN-gamma) and interleukin-4 (IL-4), as well as tumor necrosis factor (TNF), in response to direct antigen presentation by autologous and allogeneic tumor cells. We report here that, upon stimulation by autologous melanoma cells, all TIL clones secreted TNF but only a few of them produced significant amounts of IL-2, IL-4 or IFN-gamma. Nonetheless, all these clones consistently produced two or three of these last lymphokines upon stimulation with phorbol myristate acetate and calcium ionophore, as well as IL-2 upon CD3 stimulation, showing the existence of three lymphokine profiles among them: Th1, Th0 and a profile characterized by IL-2 and IL-4, but not IFN-gamma secretion. Stimulation of TIL clones by allogeneic melanoma lines sharing the appropriate HLA-peptide complexes revealed that defective IL-2 production seemed to be a constant feature for some clones, while it was, for other clones, dependent on the antigen-presenting tumor cells. For this last type of clone, we further showed that defective IL-2 induction resulted from an LFA-3 defect of some melanoma cells or from distinct yet undefined defects of other melanoma lines. Our data suggest that defective lymphokine secretion may be an essential component of the in vivo failure of melanoma-reactive TIL to control tumor development. Interestingly both CD4+ and CD8+ TIL clones from one patient were fully activated by the autologous melanoma cells in vitro, supporting a potential role of such TIL in spontaneous or induced tumor rejection.

Antibodies, Monoclonal↗
PubMed1993

Recognition of shared melanoma antigen by HLA-A2-restricted cytolytic T cell clones derived from human tumor-infiltrating lymphocytes.

Three melanoma-specific cytotoxic T lymphocytes (CTL) clones were derived from the tumor-infiltrating lymphocyte (TIL) of human melanoma M17, and were used to study the expression of immunogenic melanoma peptides on allogeneic tumors. Antibody inhibition studies showed that two of these TIL clones were restricted by an HLA-A2 molecule which was identified as A2.1 by gene sequencing. The third CTL clone was not restricted by HLA-A2, but by a B or C HLA antigen. HLA-A2-restricted CTL clones M17-1 and M17-2 lysed 5 and 12 out of 15 HLA-A2+ allogeneic melanomas, respectively. Since they did not lyse autologous Epstein-Barr virus B cells, HLA-A2.1-transfected P815 cells, 13 HLA-A2+ non-melanoma tumor cell lines and 10 HLA-A2- melanomas, these clones appeared specific for melanoma-restricted epitopes presented by the HLA-A2.1 molecule. We then tried to determine why a few HLA-A2+ melanomas were refractory to TIL lysis. By using a combination of flow cytometry analysis, partial cloning and sequencing of their HLA-A2 genes, we show that failure to lyse did not result from low expression or polymorphism of the HLA-A2 molecule, or from deficient expression of the adhesion molecules ICAM-1 and LFA-3 by these melanomas. Taken together, our data confirm at the clonal level the existence of shared melanoma antigens recognized by TIL in the HLA-A2.1 context. They further show that individual peptides derived from these antigens are expressed by a large majority of HLA-A2+ melanomas. Identification of such peptides appears crucial for the future of vaccination therapies.

Antigens, Neoplasm↗
PubMed1992

Specificity, T cell receptor diversity and activation requirements of CD4+ and CD8+ clones derived from human melanoma-infiltrating lymphocytes.

To try to understand the functional significance of human melanoma-infiltrating lymphocytes (TIL), a clonal analysis of the specificity, T cell receptor (TcR) diversity and activation requirements of these lymphocytes isolated from four different tumors was carried out. Supporting the presence of in vivo primed tumor-specific T lymphocytes in these four tumors, a high frequency of the Cd8+ and CD4+ clones, obtained from the TIL cultured for a few days with recombinant interleukin (rIL)-2 and autologous tumor cells, exhibited a restricted lysis or proliferation in response to the autologous tumor cell line. In contrast, no tumor-specific clone was obtained from freshly extracted TIL, suggesting that the frequency of tumor-specific effectors remained low in these tumors. Only the CD8+ clones lysed the autologous tumor cells and their activity was major histocompatibility complex MHC class I restricted. Significant expansion of CD4+ and CD8+ tumor-specific clones required regular restimulation by autologous melanoma cells but also the addition of exogenous IL-2 and of Epstein-Barr virus-transformed B feeder cells. Five different tumor-specific clones, three CD8+ and two CD4+ clones were identified in a single tumor on the basis of their TcR gene configuration. Together, these data suggest that a spontaneous and diverse immune response, mediated by tumor-specific CD4+ as well as CD8+ T lymphocytes, arises in most MHC-bearing human melanomas but that antigen-MHC complex presentation by tumor cells does not, at least in vitro, allow a significant proliferation of these lymphocytes.

CD4 Antigens↗
PubMed1992

Molecular analysis of a pro-T cell clone transformed by Abelson-murine leukemia virus, displaying progressive gamma delta T cell receptor gene rearrangement and surface expression.

We present a molecular analysis of T cell differentiation in a set of clones derived from in vitro Abelson murine leukemia virus (A-MuLV) infection of fetal liver cells. The parental clone had partial rearrangement of the beta and gamma loci and spontaneously displayed progressive rearrangement of V gamma genes during in vitro culture. Further differentiation of these clones leading to delta gene rearrangement and CD4 expression, then CD8, CD3 and T cell receptor gamma delta chain surface expression was obtained after intrathymic transfer followed by in vitro co-culture with thymic tissue. These A-MuLV clones, therefore, appear to represent a powerful model system for studying the early molecular events of T cell development at the clonal level.

Abelson murine leukemia virus↗
PubMed1992

Patterns of responsiveness of T cell lines and thymocytes reveal waves of specific activity in the post-natal murine thymus.

Antibody binding of CD3, CD4, or CD8 molecules can induce cytoplasmic calcium mobilization in T lymphocytes, usually interpreted as indicating signal transduction. Using such assays, in a CD4+ CD8+ thymocyte line and its single positive progeny we have identified characteristic patterns of responsiveness that are reproducible in vivo in a subpopulation of newborn 'double positive' thymocytes but virtually absent in adult thymuses. In particular, these cells appear to be high responders to the binding of anti-CD3 F(ab)'2 fragments. We have followed the presence of such highly responsive thymocytes in the perinatal period and the first 15 days of life. Intriguingly, these cells populate the newborn thymus in three distinct waves. Such patterns of responsiveness may define early 'selectable' thymocytes.

Animals↗
PubMed1991

High-fold expansion of human cytotoxic T-lymphocytes specific for autologous melanoma cells for use in immunotherapy.

We set up a culture protocol that consistently allows high-fold expansion of tumor-specific T-lymphocytes from most melanoma-invaded biopsies with low doses of recombinant interleukin-2 (rIL-2). Between 2-60 x 10(6) T-lymphocytes could be obtained and cryopreserved from 12 out of 13 patients, by culturing only 50 mm3 tumor tissue with rIL-2. Thawed lymphocytes from 11 of these patients could then be expanded by a median factor of 32,800 by culturing them successively in microplates on irradiated feeder cells with rIL-2 for approximately 2 weeks and then in culture bags or flasks with only rIL-2 for 1-2 additional weeks. Dead feeder cells disappeared during the last phase of the lymphocyte culture with rIL-2. Interestingly, each time they were expanded under these conditions, tumor-infiltrating lymphocytes (TIL) or lymph-node lymphocytes developed a lytic activity apparently restricted to the autologous melanoma line. Tumor-specific lysis, which was maximum at around the end of T-lymphocyte expansion, ranged between 31-63% lysis at an effector:target (E:T) ratio of 20:1. This culture method would thus appear to be suitable for reliable production of over 10(10) T-lymphocytes with good tumor-specific lytic activity from most melanoma-invaded biopsy. It should permit analysis of the immunotherapeutic potential of these populations reinjected into cancer patients.

Cell Division↗
PubMed1990

Fucose and galactose receptor and liver recognition by lymphoma cells.

A syngeneic model system for the study of metastases is described. The system consisted of 2 lymphoma clones (A/63-I and A/63-2) derived from a single thymoma (A/63) induced by a wild-type Abelson-Moloney viral complex. Phenotype and genotype analyses revealed that both clones were derived from transformation of early T-cell precursors. An in vivo study of the colonizing potential following intravenous (i.v.) injection of clones showed that only the A/63-I cell clone colonized the liver. This observation was confirmed by quantitative analysis of organ distribution of both cell clones consecutive to i.v. injection of 125IUdR-labelled cells. In the same way, an in vitro study of the invasive potential of both clones was performed on frozen liver sections and showed that only the A/63-I cell clone had the ability to attach to liver. This specific adhesion was inhibited by L-fucose, D-galactose, N-acetyl-D-galactosamine (D-GalNAc) and with D-galactose- and L-fucose-containing neoglycoproteins. Differences in cell surface carbohydrates of the 2 cell clones were detected using various lectins: peanut agglutinin (PNA), Dolichos biflorus (DBA), Aleuria aurantia (AAA) and Galactia tenuiflora agglutinins (GTA). A/63-I was found to react strongly with PNA, DBA and GTA, and the removal of sialic acid by neuraminidase treatment increased DBA and PNA receptor sites of A/63-2 as compared to A/63-I. The present data suggest that cell-surface GalNAc, galactosyl and fucosyl residues are responsible for the ability of the A/63-I cell clone to recognize liver tissue probably through binding to a Kupffer-cell-associated lectin.

Abelson murine leukemia virus↗
PubMed1990

Selective expansion of a specific anti-tumor CD8+ cytotoxic T lymphocyte clone in the bulk culture of tumor-infiltrating lymphocytes from a melanoma patient: cytotoxic activity and T cell receptor gene rearrangements.

In vitro culture of metastatic melanoma fragments with 150 units of recombinant interleukin 2 resulted in the successive expansion of CD4+ and then CD8+ tumor-infiltrating lymphocytes (TIL) throughout a 2-month period. TIL cultured for 43 days and consisting of 95% CD8+ and 10% CD4+ T lymphocytes were cloned by limiting dilution (LD). Thirteen CD8+ and thirty-one CD4+ clones were obtained, indicating that the frequency of clonogenic CD8+ proliferative T lymphocytes was much lower than that of their CD4+ homologues. When LD was performed in the presence of autologous melanoma cells the frequency of CD8+ clones was increased by factor 4. The DNA from TIL of day 43 bulk culture and of six CD8+ clones was hybridized with T cell receptor (TcR) beta and gamma probes. Identical configuration of the nonfunctional gamma and functional beta TcR genes was found in "bulk culture" and cloned TIL. The CD8+ clones therefore derived from a clonal population of CD8+ cells which had expanded in vitro before the LD. All the CD8+ clones tested were strongly cytotoxic for autologous melanoma cells but did not kill autologous fibroblasts or concanavalin A blasts, or any of the 10 allogeneic tumor targets tested, including 5 melanomas, 2 breast cell lines, 1 neuroblastoma, K-562 and the Epstein-Barr virus-transformed cell line used as a feeder. Furthermore, specific killing was inhibited by monoclonal antibodies against CD3, CD8, TcR alpha/beta and against class I major histocompatibility complex antigens indicating that these cytotoxic T lymphocyte clones recognized autologous tumor cells through the TcR, in an HLA class I-restricted manner. These data show that it is feasible to obtain tumor-specific cytotoxic T lymphocytes from melanoma TIL with a simple culture technique and that a single clone could be expanded to more than 10(10) cells which should allow testing of immunotherapeutic potential of these cells by adoptive transfer into melanoma patients.

Antibodies, Monoclonal↗
PubMed1990

High proliferative capacity and specific antiautologous melanoma cytotoxicity of a human T-lymphocyte clone derived from tumor-infiltrating lymphocytes.

A CD8+ clone, identified by its T-cell receptor gamma- and beta-gene configuration, was shown to preferentially develop, in the bulk culture of melanoma tumor-infiltrating lymphocytes with recombinant interleukin 2 after 1 month. Thirteen CD8+ clones were obtained by limiting dilution culture of tumor-infiltrating lymphocytes from 43-days old culture. Four of these clones, analyzed for T-cell receptor rearrangements, exhibited exactly the same T-cell receptor gene pattern as tumor-infiltrating lymphocytes from the bulk culture, showing, therefore, that all the CD8+ clones were subclones. All the 13 CD8+ subclones were strongly cytotoxic for autologous melanoma cells but did not kill K562. A more complete cytotoxicity analysis showed that the clones did not kill autologous fibroblasts or Con A blasts or allogeneic tumor targets. Furthermore, specific killing was inhibited by monoclonal antibodies against CD3, CD8, T-cell receptors alpha beta, and class I major histocompatibility complex antigens indicating that effector-to-target cell recognition was mediated through the T-cell receptor in a major histocompatibility complex-restricted fashion. These data showed that human melanoma-specific cytotoxic T lymphocytes can be obtained from melanoma TIL and that a single cytotoxic T lymphocyte clone can be expanded to more than 10(10) cells without a loss of autotumor specificity.

Antibodies, Monoclonal↗
PubMed1987

Cell kinetics in the fetal mouse thymus: precursor cell input, proliferation, and emigration.

The entry and differentiation of lymphoid precursor cells (LPC) in grafted mouse fetal thymuses and the emigration of explants thymocytes has been followed in a system in which donor and host lymphocytes could be distinguished on the basis of Thy-1 expression. It appears that LPC that invade the fetal mouse thymus between 10 and 13 days rapidly differentiate into Thy-1 positive thymocytes, giving rise to all of the lymphoid populations of both cortical and medullary locations until approximately the end of the first week after birth. Lymphoid precursor cells that enter the fetal thymus after 13 days of fetal life only differentiate into Thy-1 positive lymphocytes 6 or 7 days after birth, when they give rise to a second generation of thymocytes that grows exponentially and completely replaces the first generation in approximately 8 days. All cells leaving the thymus during the first 2 wk of life appear to be derived from the first wave of precursors.

Animals↗