Identification of a second T-cell antigen receptor in human and mouse by an anti-peptide gamma-chain-specific monoclonal antibody

Human abdominal aortic aneurysm (AAA): Evidence for an autoimmune antigen-driven disease

Abdominal aortic aneurism (AAA) is a complex immunological disease with a strong genetic component, and one of the ten leading causes of death of individuals 55-74 years old worldwide. Strong evidence has been accumulated suggesting that AAA is an autoimmune specific antigen-driven disease. Mononuclear cells infiltrating AAA lesions comprised of T and B lymphocytes and other cells expressing early-, intermediate- and late-activation antigens, and the presence of antigen-presenting cells have been documented, demonstrating an ongoing immune response. The three components of the trimolecular complex, T-cell receptor (TCR)/peptide (antigen)/HLA have been identified in AAA, and specifically: (i) clonal expansions of T-cell clones in AAA lesions; (ii) the association of AAA with particular HLA Class I and Class II; and (iii) self or nonself putative AAA-associated antigens. IgG autoantibodies recognizing proteins present in normal aortic tissue have been reported in patients with AAA. Molecular mimicry, defined as the sharing of antigenic epitopes between microorganisms (bacteria, viruses) and self antigens, maybe is responsible for T-cell responses and antibody production in AAA. Also, the frequency and the suppressor activity of CD4 + CD25 + FOXP3+ Tregs and the expression of FOXP3 transcripts and protein have been reported to be significantly impaired in AAA patients vs normal donors.

Human breast tumor cells express IL-10 and IL-12p40 transcripts and proteins, but do not produce IL-12p70

IL-10 transcripts were expressed in 14/15 primary breast adenocarcinomas and in 5/8 established breast tumor lines. Immunohistochemistry and immunoprecipitation from lysates and supernatants revealed that established breast tumor lines produced IL-10 protein. Immunohistochemistry revealed that IL-10 is localized to tumor cells of primary breast adenocarcinomas and to occasional infiltrating MNC. Established breast tumor cell lines expressed IL-12p40 transcripts (6/8) and protein (4/7) and IL-12p35 transcripts (6/7). Using two sandwich ELISAs, specific, respectively, for IL-12p40 and IL-12p70 proteins, we demonstrated that established breast tumor cell lines produce IL-12p40 monomer/homodimer, but not IL-12p70. Positive staining for IL-12p70 in primary breast adenocarcinomas was found only in MNC infiltrating the tumor while tumor cells were negative. IL-12p40 homodimer/monomer inhibit as antagonists IL-12 or IL-23, although they may also act as agonists and positive regulators. Also, primary breast adenocarcinomas (15/15) and established breast tumor cell lines (6/8) expressed TGF-β1 transcripts. IL-10, IL-12p40 and TGF-β1 may inhibit substantially the anti-tumor immune response.

Characterization of a newly discovered T-cell receptor beta-chain heterodimer expressed on a CD8+ bone marrow subpopulation that promotes allogeneic stem cell engraftment

The facilitating cell is a rare CD8+ bone marrow subpopulation that can enhance allogeneic hematopoietic stem cell engraftment across complete major histocompatibility complex barriers without inducing acute graft-versus-host disease. Here we describe a CD3epsilon-associated complex on the facilitating cell surface that consists of the T-cell receptor beta-chain disulfide-linked to a previously unknown 33-kilodalton glycoprotein. Provisionally called FCp33, this glycoprotein does not represent any of the known protein chains or surrogates associated with CD3-T-cell receptor beta. Expression of this CD3-T-cell receptor beta-FCp33 complex directly correlates with the facilitating cell's functional ability to enhance allogeneic stem cell engraftment in vivo.

Selective gamma-chain T-cell receptor gene rearrangements in a patient with Omenn's syndrome: absence of V-II subgroup (V gamma 9) transcripts

Only gamma-chain T-cell receptor transcripts utilizing V-1 subgroup gene segments were found in peripheral blood lymphocytes from a patient with Omenn's syndrome. gamma-Chain T-cell receptor transcripts utilizing the V gamma 9 (V-II subgroup) gene segment were absent in peripheral blood lymphocytes from this patient. V gamma 9 J gamma 1.2 C gamma 1 rearrangements are those primarily found in peripheral blood lymphocytes (70 to 85%) from normal donors.

Immunopathogenesis of juvenile rheumatoid arthritis: role of T cells and MHC

Juvenile rheumatoid arthritis (JRA) is defined as chronic arthritis of unknown etiology appearing in patients less than 16 years of age. The disease is heterogeneous and is classified as pauciarticular, polyarticular, or systemic-onset disease. A few lines of evidence suggest that T cells are involved in the pathogenesis of the disease. T cells infiltrating the synovial membrane bear markers of activation and produce cytokines. The association of particular subtypes of JRA with certain HLA class II alleles provides strong evidence in favor of T cell involvement through an HLA-peptide-T cell receptor complex. Limited data from a few patients with JRA on T cell receptor transcripts from synovial membrane or synovial fluid cells point towards oligoclonality. This further supports the concept that T cells infiltrating the synovial membrane or extravasating into synovial fluid in patients with JRA reflect antigen-driven T cell proliferation.

Differences between inner membrane and peptidoglycan-associated PBP1B dimers of Escherichia coli

Earlier studies revealed that PBP1B of Escherichia coli occurred as a monomeric as well as a dimeric form (C.A.L. Zijderveld, M.E.G. Aarsman, T. den Blaauwen, and N. Nanninga, J. Bacteriol. 173:5740-5746, 1991). In this study, the dimer of PBP1B was further analyzed. It appeared that the dimeric form could be divided into two classes. One class, which cofractionated with the cell wall fraction, could be artificially cross-linked to peptidoglycan, indicating a close association with the latter. This class of PBP1B dimers was sensitive to beta-mercaptoethanol. The second class, like the monomeric form of PBP1B, could be isolated with the inner membrane fraction. This dimeric form dissociated in the presence of zinc in combination with beta-mercaptoethanol.

Characterization of T-cell receptor V beta repertoire in ovarian tumour-reacting CD3+ CD8+ CD4- CTL lines

T cells from tumour infiltrating lymphocytes (TIL) cultured in media containing IL-2 were shown to mediate in vitro and in vivo antitumor responses. To characterize the T-cell antigen receptor (TCR) V beta expression in autologous cytotoxic effectors we isolated CD3+ CD8+ CD4- cells from cultures of TIL and tumour-associated lymphocytes (TAL) and analysed the TCR V beta repertoire of CD3+ CD8+ CD4- lines of known HLA-A, -B and -C phenotype, using polymerase chain reaction (PCR). These lines showed preferential lysis of autologous tumours and lysed, to a much lesser extent, NK and LAK cell-sensitive targets. Tumour lysis was inhibited by antibodies to CD3 and MHC class I antigens indicating that they are cytotoxic T lymphocytes (CTL). These CD8+ CTL lines expressed a broad distribution of TCR V beta repertoire which was dominated by particular groups of V beta families in each CTL line. However, no predominant expression of one or the same V beta segment in all CTL lines was observed although statistical correlations between V beta family usage and magnitude of the antitumour cytolytic response were found. These results suggest that certain TCR V beta families may be selected by antigen in ovarian tumour-reactive T cells and this selection may be affected by Ag expression, and/or host factors. To our knowledge, this is the first documentation of TCR V beta repertoire of human ovarian tumour-reactive CD3+ CD8+ CD4- CTL from different individuals of known HLA types.

T-cell antigen receptors in rheumatoid arthritis

Rheumatoid arthritis (RA) is a systemic disease of unknown etiology characterized by chronic inflammation mainly in the joints. Several lines of evidence suggest that T cells are involved in the pathogenesis of the disease. RA is associated with certain HLA-DR alleles. Studies analyzing T-cell receptor transcripts in RA have found biased or preferential usage of certain V alpha and/or V beta gene segments by T cells infiltrating the synovial membrane or extravasating into the synovial fluid compared to peripheral blood. In certain patients few T-cell antigen receptor (TCR) clones dominated the infiltrating T cells, suggesting that T cells from the synovial membrane or the synovial fluid comprise oligoclonal populations of T cells. However, other studies have found a polyclonal population of T cells. In interpreting these results the phase of the disease (early vs. late RA), the source of T cells and the limitations of the methods used in these studies should be taken into consideration. However, it appears that synovial T cells comprise oligoclonal populations of T cells and that there is a bias towards particular TCR gene segments, although a specific TCR gene segment in RA has not emerged.

Preferential rearrangements of the V gamma I subgroup of the gamma-chain of the T-cell antigen receptor to J gamma 2C gamma 2 gene segments in peripheral blood lymphocyte transcripts from normal donors

To investigate whether there are preferential VJC gene rearrangements of the gamma-chain of the human T-cell antigen receptor (TCR), we amplified and sequenced gamma-chain TCR transcripts from peripheral blood lymphocytes from adult normal donors. cDNA was synthesized from total RNA and amplified by the polymerase chain reaction (PCR) using 5' primers specific for either the V gamma I or the V gamma II subgroups of the gamma-chain of the TCR. The amplified cDNAs were then cloned and sequenced. The majority (approximately 83%) of the cDNAs employing V-I subgroup gene segments rearranged to J gamma 2 (J gamma 2.1 or J gamma 2.3) C gamma 2 gene segments. This was in contrast to the predominant rearrangement of the V gamma II subgroup (V gamma 9) to J gamma 1.2C gamma 1. The remaining 13% of the cDNAs employing V gamma I subgroup gene segments rearranged to J gamma 1.1C gamma 1 or J gamma 1.3C gamma 1. There was significant N diversity as well as imprecise joining at the VJ junction. gamma delta TCR utilizing the C gamma 1 gene segment are disulfide-linked, whereas those utilizing the C gamma 2 gene segment are non-disulfide-linked. These results demonstrate that peripheral blood gamma-chain transcripts exhibit preferential rearrangements of V gamma I subgroup gene segments to J gamma 2(2.1,2.3)C gamma 2 gene segments. By contrast, V gamma II subgroup (V gamma 9) transcripts exhibit rearrangements to J gamma 1.2C gamma 1.

Cytotoxic T-cell clones isolated from ovarian tumour infiltrating lymphocytes recognize common determinants on non-ovarian tumour clones

CTL-TIL lines have been developed from tumour infiltrating lymphocytes (TIL) from the ascites of patients with ovarian carcinoma, and used to investigate whether common tumour antigens are expressed on allogeneic ovarian tumours epithelial tumour lines derived from colon and pancreatic carcinoma. Three CTL lines expressed preferential cytolytic activity against autologous tumour cells and against certain allogeneic ovarian tumour cells that shared HLA-A2 molecules. Analysis of the target specificity of these CTL lines indicated that they also lysed human colon and pancreatic tumour lines sharing HLA-A2. CTL-TIL clones isolated from these lines were found to lyse HLA-A2+ ovarian, colon and pancreatic tumours, and to recognize clonally distributed common epitopes on pancreas and colon tumour clones. These results indicate that shared tumour antigens can be found among tumours of common epithelial cell origin. These results indicate a novel class of T-cell-definable tumour antigens recognized by tumour-reactive CTL on human tumours and may be significant for understanding of cellular immunity in ovarian cancer, identification of CTL-defined tumour antigens and future adoptive specific immunotherapeutic approaches in ovarian cancer.

Gamma/delta T cell antigen receptors expressed on tumor-infiltrating lymphocytes from patients with solid tumors

The expression of gamma/delta T cell antigen receptors (TcR) in T cell lines or clones derived from tumor-infiltrating lymphocytes (TIL) from patients with solid tumors was investigated. gamma/delta TcR T cell lines were derived from TIL from patients with Wilms tumor, sarcoma or metastatic melanoma by stimulation with autologous tumor cells alone and recombinant interleukin 2 and they exhibited nonspecific cytotoxicity against autologous and allogeneic tumor cells, or cells of the K562 or the MEL21 tumor cell lines. Two T cell lines were derived from a patient with Wilms tumor. One of them expressed a non-disulfide-linked gamma/delta TcR using the 60-kDa gamma chain, whereas, the other expressed a disulfide-linked gamma/delta TcR. A T cell line was derived from a patient with sarcoma and expressed a disulfide-linked gamma/delta TcR, whereas, a T cell line derived from a patient with melanoma expressed a non-disulfide-linked gamma chain of 62 kDa. Several T cell clones were developed from patients with metastatic melanoma or Wilms tumor and expressed either disulfide- or non-disulfide-linked gamma/delta TcR. Northern analysis of RNA from certain of these clones revealed a full-length gamma chain transcript, whereas, the alpha or beta chain transcripts were either absent or truncated. These T cell clones exhibited nonspecific cytotoxicity. Both disulfide- and non-disulfide-linked TIL T cell lines and clones expressed the delta TCS1 determinant. gamma/delta TcR+ cells in freshly prepared TIL from these patients were present in low proportions (less than 5%) and their delta TCS1/delta 1 ratios were within the range observed in the peripheral blood of normal donors. These results demonstrate that both disulfide- and non-disulfide-linked gamma/delta TcR are expressed on T cell lines and clones derived from TIL from solid tumors. Non-disulfide-linked gamma/delta TcR using the 56-66-kDa gamma chain are frequently found on TIL-derived T cell lines and clones. These 56-66-kDa gamma chains are rarely expressed on T cell lines or clones derived from peripheral blood lymphocytes of normal donors.

Induction of interleukin-2 receptor by tumor necrosis factor alpha on cultured ovarian tumor-associated lymphocytes

We have recently reported that autologous tumor-specific cytotoxic T lymphocyte (CTL) lines and clones can be developed from lymphocytes infiltrating ovarian malignant ascites (TAL). In this study, we investigated the biological effects of tumor necrosis factor alpha (TNF alpha) in the induction, expansion, long-term proliferation and lytic function of CD8+ TAL. TNF alpha up-regulated the IL-2 receptor (IL-2R) alpha chain (Tac antigen) on the surface of CD3+ CD8+ CD4- TAL, enhanced the proliferation of autologous tumor-specific CTL, and potentiated their lytic function in long-term cultures. Furthermore, in the induction and expansion phase of CD8+ TAL, the presence of TNF alpha was associated with a selective increase in CD8+ IL-2R+ (Tac+) cells, and subsequent decrease in CD4+ IL-2R+ (Tac+) cells. These results suggest that the observed facilitation of the outgrowth of CD8+ cells in TAL cultures may be due, at least in part, to the up-regulation of IL-2R, and indicate the usefulness of TNF alpha in the analysis of signalling in autologous tumor-reactive CTL.

IL-2-dependent murine T-cell lines and clones expressing gamma/delta T-cell antigen receptors. I. Functional and biochemical characterization

We have developed two stable IL-2-dependent T-cell lines designated AKV-I and AKV-N from the enlarged spleens, respectively, of an AKV1 and an NFS mouse. Immunofluorescence staining with the appropriate monoclonal antibodies revealed that cells of the AKV-I cell line were alpha beta TCR-CD3+CD4-CD5-CD8+CD25+, whereas cells of the AKV-N cell line were alpha beta TCR-CD3+CD4-CD5+CD8-CD25+. A number of T-cell clones were developed from the AKV-I or AKV-N T-cell lines by limiting dilution and analysed by immunofluorescence. All clones tested were alpha beta TCR-CD3+CD4-CD25+. Certain T-cell clones expressed the CD5 antigen, whereas others expressed the CD8 antigen. The AKV-I cell line responded by proliferation to rIL2, rIL4, phorbol myristate acetate (PMA), PMA plus IL-4 and PMA plus PHA or Con A. In contrast, the AKV-N cell line did not respond to rIL-4 or rIL-4 plus PMA and exhibited only a modest proliferative response to PMA alone. Both AKV-I and AKV-N T-cell lines as well as a large number of T-cell clones examined were able to lyse cells of the PU5-IR murine cell line in the presence of the anti-CD3 (clone 145-2C11) MoAb, demonstrating their ability to mediate cytotoxicity in this system. Biochemical analysis of both AKV lines and a number of clones by immunoprecipitation with the anti-CD3 MoAb, followed by one-dimensional (either non-reducing or reducing) or two-dimensional (non-reducing/reducing) SDS-PAGE, revealed that the AKV lines and clones expressed a disulphide-linked dimer. Under non-reducing conditions, a band in the range of 75-85 kDa was observed and upon reduction it was resolved into two discrete polypeptide chains of 43-44 kDa and 48 kDa in certain AKV-I cells or 38 kDa and 42 kDa in certain AKV-N cells. In other T-cell clones or lines a broad band of 42-47 kDa was observed in AKV-I cells or 38-45 kDa in AKV-N cells. These results suggest the presence of different forms of disulphide-linked dimers on these cells. Northern blotting analysis using probes specific for the constant regions of the alpha-, beta-, gamma- and delta-chains of the T-cell antigen receptor revealed that all the AKV cell lines or clones tested expressed full-length alpha-, gamma- and delta-chain mRNA, whereas beta-chain mRNA was absent.(ABSTRACT TRUNCATED AT 250 WORDS)

Tetanus toxin receptor. Specific cross-linking of tetanus toxin to a protein of NGF-differentiated PC 12 cells

A subclone of rat pheochromocytoma cells expresses high affinity receptors for tetanus toxin on differentiation with NGF [Walton, K.M., Sandberg, K., Rogers, T.B. and Schnaar, R.L. (1988) J. Biol. Chem. 263, 2055-2063]. In the presence of protein cross-linking agents, [125I]tetanus toxin, bound to these cells at 0 degree C, forms a cross-linked product with apparent molecular weight of 120 kDa. The formation of [125I]tetanus toxin conjugate involves the heavy chain of the toxin, is prevented by cold toxin and it is largely reduced by pretreating cells with proteases. The cross-linked product is formed only upon incubation of the toxin with NGF-differentiated cells. These results suggest that a protein with apparent molecular weight of 20 kDa is involved in the neurospecific binding of tetanus toxin.

Development of a cell surface reacting human monoclonal antibody recognizing ovarian and certain other malignancies

A human monoclonal antibody designated AC6C3 was developed by fusing regional lymph node lymphocytes from a patient with epithelial ovarian carcinoma with cells of the hybrid myeloma SPAZ 4. This monoclonal antibody recognized a determinant expressed on the cell surface of ovarian tumor cell lines. The AC6C3 hybridoma has been maintained for more than 24 months by repeated cloning and secretes IgM at concentrations of 2-8 micrograms/10(6) cells/24h. The AC6C3 monoclonal antibody reacted with a cell surface component of ovarian tumor cell lines, as determined by cell surface immunofluorescence staining using the fluorescent activated cell sorter (FACS). In contrast, nylon wool nonadherent peripheral blood lymphocytes or red blood cells from normal donors were negative (less than 5% of the cells were stained). Immunoperoxidase staining with the AC6C3 monoclonal antibody of nonpermeabilized cryostat sections of freshly obtained or cryopreserved ovarian carcinoma specimens and human ovarian tumor xenografts demonstrated strong reactivity of these specimens. Most normal tissues including brain, liver, heart, kidney and peritoneum demonstrated negative or weak reactions with AC6C3. Other carcinomas including breast, colon and some malignancies of neuroectodermal origin were strongly reactive with AC6C3. AC6C3 mediated complement-dependent cytotoxicity and identified a 32 Kd band in Western blotting and immunoprecipitation experiments conducted on surface labelled SKOV3 cells. The association constant for AC6C3 was determined at 2.3 x 10(10) M-1.

T cell responses to ovarian tumor vaccines: identification and significance for future immunotherapy

The cellular immune responses to ovarian cancer patients treated with viral oncolysates (VO) ovarian tumor vaccines to vaccines are described. CD3+ cells proliferated after stimulation with the tumor vaccines in a dose-dependent manner. The proliferation of CD3+ cells stimulated with the tumor vaccine was blocked by anti-HLA-DR monoclonal antibody and anti-CD4 mAb indicating that CD3+ CD4+ cells from the blood of the patients treated with VO recognize tumor derived determinants in conjunction with MHC class II antigens. The regulatory activity of the T cells collected after VO treatment was assayed by co-cultivation with PBMC collected before VO treatment. These cells demonstrated increased helper activity for immunoglobin production by cells collected before vaccination and secreted IL-2 in response to stimulation by vaccine. Finally, when biochemical fractionation of the components of VO was attempted, PBMC from VO treated patients responded by proliferation to several fractions suggesting that they recognize multiple epitopes in the ovarian tumor vaccine. Therefore, these data provide novel evidence for the involvement of the T cells in response to ovarian tumor vaccines.

Disulfide-linked gamma delta T cell antigen receptors expressed on T cells derived from patients with primary immunodeficiency disorders

T cell lines or clones from two patients, one with a partial DiGeorge syndrome and one with severe common variable immunodeficiency expressed disulfide-linked gamma delta T cell antigen receptor (TCR) comprised of a gamma-chain polypeptide of 40-43 kD, and a delta-chain polypeptide of 37-40 kD. This gamma delta TCR appears to be similar to that found on T cell clones, and lines derived from peripheral blood lymphocytes from normal donors. Previous studies have shown that T cell lines derived from the peripheral blood of patients with immunodeficiency disorders express non-disulfide-linked gamma delta TCR. In contrast to the latter and coincident with findings in the present study, the vast majority of T cell lines and clones derived from the peripheral blood of normal donors express disulfide-linked gamma delta TCR.

Specific, major histocompatibility complex-unrestricted recognition of tumor-associated mucins by human cytotoxic T cells

We have previously reported the establishment of cytotoxic T-cell lines from pancreatic cancer patients, by continuously stimulating tumor-draining lymph node cells with allogeneic pancreatic tumor cell lines. After the preliminary characterization of their phenotype and tumor specificity, detailed studies performed with one of the cell lines, W.D., show that it recognizes a specific antigen, a large and heavily glycosylated mucin molecule, expressed on pancreatic and breast tumors and tumor cell lines. Although this recognition appears major histocompatibility complex (MHC)-unrestricted, the antigen receptor used by the cytotoxic T cell is the alpha/beta heterodimer, typically found on MHC-restricted T cells. The target antigen is atypical, however, in its ability to directly bind and activate the T cells in the absence of self MHC, presumably by abundant and regularly repeated antigenic epitopes. These findings are important because they demonstrate a specific T-cell response against a human tumor-associated antigen. In addition to pancreatic and breast tumors, various mucin molecules are known to be produced by other tumors of epithelial cell origin and could be expected to stimulate similar T-cell-mediated immune responses.

Development of a monoclonal antibody specific for the gamma chain of the T-cell antigen receptor using an open reading frame expression vector

To develop an anti-framework monoclonal antibody (mab) specific for the gamma (gamma)-chain of the T-cell antigen receptor (TCR), we expressed a part of the constant region of the gamma-chain (C gamma 2 gene segment) in E. coli using the pWR590 vector. This plasmid contains the E. coli lac promoter, operator, a truncated beta-galactosidase (beta-gal) gene (coding for the first 590 of the 1,007 amino acids of the beta-gal) and a polylinker region (at the 3' end of the beta-gal) containing nine restriction sites. These can be cleaved by any one of eight common restriction enzymes, permitting the introduction of the DNA fragment of interest. We employed the pT gamma 1 gamma-chain cDNA probe, which like the vast majority of the gamma-chain specific probes is aberrant and contains an in-frame stop codon at the junction of V and J regions. Computer analysis of the pT gamma 1 sequence revealed several MaeIII restriction sites that could result in a number of fragments. One of these fragments consisted of 245 base pairs (nucleotides 404-648) and contained most of the CI exon of the C gamma 2. Successful insertion of this fragment to the pWR590 vector was confirmed using restriction enzyme analysis. The C gamma insert was 12% of the construct. Expression of the pWR590-HpT gamma 1 recombinant plasmid in E. coli followed by SDS-PAGE analysis revealed a hybrid protein with a molecular weight of 85 kd which constituted at least 25% of the total E. coli insoluble protein. In contrast, cells transformed with the control pWR590 vector without insert expressed a 78 kd polypeptide chain. We developed several mabs against the pWR590-HpT gamma 1 hybrid protein by fusing spleen lymphocytes from BALB/c mice immunized with the pWR590-HpT gamma 1 protein, with cells of the NS1 mouse myeloma cell line. Screening of the mabs was carried out by ELISA against the pWR590-HpT gamma 1 hybrid protein and the control pWR590 beta-gal protein (beta-gal 590), derived by expressing in E. coli the pWR590 vector without gamma-chain insert. Two groups of mabs were obtained, those reacting with the pWR590-HpT gamma 1 hybrid protein only and those reacting with both the hybrid and the control beta-gal 590 proteins. The specificity of these mabs was further studied by Western blotting with similar results.(ABSTRACT TRUNCATED AT 400 WORDS)

Molecular heterogeneity of gamma delta T-cell antigen receptors expressed by CD4- CD8- T-cell clones from normal donors: both disulfide- and non-disulfide-linked receptors are delta TCS1+

We investigated the molecular heterogeneity of gamma delta T-cell antigen receptors (TCR) expressed on T-cell clones generated from peripheral blood lymphocytes of normal donors. Extensive molecular heterogeneity was seen at the gamma-chain level and, to a lesser extent, at the delta-chain level. Both disulfide and non-disulfide gamma delta TCR were found and use different gamma chains with similar molecular masses (range, 41-43 kDa). In contrast, gamma chains of 55-60 kDa, which are expressed on T-cell lines derived from the peripheral blood of patients with immunodeficiency disorders, were not found on T-cell clones derived from the peripheral blood of normal donors. delta chains expressed on these T-cell clones had a molecular mass of 37 kDa and were either disulfide or nondisulfide linked. Significant delta-chain heterogeneity was identified in these clones using the anti-delta TCS1 and the anti-TCR delta 1 monoclonal antibodies. All clones tested were TCR delta 1+, whereas only 25% of the clones were delta TCS1+. The anti-delta TCS1 monoclonal antibody stained and immunoprecipitated both disulfide- and non-disulfide-linked gamma delta TCRs from different T-cell clones from normal donors.

Application of a T cell receptor antibody beta F1 for immunophenotypic analysis of malignant lymphomas

One hundred sixty-five non-Hodgkin's lymphomas (101 B, 63 T, one histiocytic) were immunostained with an antibody (beta F1) reactive with a common framework determinant on the beta-subunit of the T cell receptor (TCR). beta F1 stained T lymphomas exclusively, including 53% of peripheral T cell lymphomas but only 33% of T lymphoblastic lymphomas. When expression of beta F1 and CD3 were considered together, 4 types of T lymphoma were delineated: 1) beta F1+CD3+; 2) beta F1+CD3-; 3) beta F1-CD3+, and 4) beta F1-CD3-. The first represented lymphomas with classical T immunophenotype. The second might represent T lymphomas with aberrant loss of CD3 expression. The third might represent T lymphomas with a putative second TCR or cases with an immature phenotype expressing cytoplasmic CD3 only. The fourth type included cases that may be derived from natural killer cells instead of T cells, cases of T lymphoma with aberrant loss of both beta F1 and CD3, and some cases of immature T cell (lymphoblastic) lymphoma. beta F1-CD3- lymphomas exhibited a remarkable predilection for the nasal region. beta F1 is useful in studying T cell lymphomas and distinguishing a novel immunophenotype frequently expressed by nasal lymphomas.

Genetics and strain distribution of concanavalin A-reactive Ly-2-, L3T4- peripheral precursors of autoreactive T cells

Cytotoxic treatment of BALB/c cells from different peripheral lymphoid tissues by a cocktail of monoclonal antibodies against Thy-1, Ly-1, L3T4 and Ly-2 differentiation markers (anti-T cocktail) plus complement eliminates all mature T lymphocytes. Yet a population of dull Thy-1+, Ly-1-, L3T4-, Ly-2-, corresponding to about 1% of the initial population, can be detected by flow cytometry which proliferate under concanavalin A stimulation. These anti-T killing-resistant cells (TKR) were previously shown to be capable of differentiating in culture into class II-restricted autoreactive T helper cells. We demonstrate here that such cells can be detected in mice of BALB/c and DBA/2 genetic background but are absent in C57BL/6 and B10 animals. The presence of TKR cells is dominant in (BALB/c x C57BL/6)F1 hybrids and genetically controlled by two genes which are neither H-2 nor Igh linked. TKR cells are also detected in young NZB mice but disappear with the development of the systemic autoimmune disease in old animals. Thy-1+, L3T4-, Ly-2- cells from MRL lpr/lpr mice also respond to concanavalin A but are removed by the anti-T treatment. Altogether, arguments are presented suggesting that TKR cells represent a particular subset of double-negative peripheral T cells which may correspond to autoreactive T cell recursors that would escape the thymic selection. We postulate that these cells are present in all mouse strains but their susceptibility to killing by anti-Thy-1 antibodies differs depending on background genes.

Unusual forms of T cell gamma mRNA in a human T cell leukemia cell line: implications for gamma gene expression

The expression and rearrangement of T cell rearranging (TRG) gamma genes in human leukemic cell lines has been examined. The cell line MOLT-17 produces abundant gamma mRNA which is translated into a protein found on the cell surface which is associated with the CD3 molecule. The analysis of the gamma mRNA sequences in MOLT-17, by cDNA cloning, shows transcripts of aberrantly rearranged genes as well as the productively rearranged allele. The productive allele consists of a rearranged V gamma 8 gene joined to J gamma 2. Two forms of aberrant transcript originate from the other rearranged gamma allele. One of these initiates just upstream of the unrearranged J gamma 2 segment, and the other initiates from a V gamma 8 gene segment joined to another J gamma segment, upstream of J gamma 2. An unusual feature of the latter transcript is that polyadenlyation has occurred at the end of the first exon of C gamma 2, where two conserved poly(A) addition signals occur. The MOLT-4 cell line, on the other hand, has productively and nonproductively rearranged gamma alleles, from which relatively little transcription occurs. These results define new J gamma segments in the human TRG gamma locus and suggest that positive activation of the gamma locus is necessary for high level transcription after rearrangement.

Anti-Thy-1-induced proliferation of immature thymocytes expressing the CD3-associated gamma/delta heterodimer

A series of rat monoclonal antibodies (mAb) directed against the Thy-1 molecule have been evaluated for their ability to stimulate immature (CD4-8-) murine thymocytes. CD4-8- thymocytes could be induced to proliferate by several anti-Thy-1 mAb provided that exogenous interleukin 1 or interleukin 2 was provided. Apparently non-stimulatory anti-Thy-1 mAb could be rendered stimulatory if cross-linked by a rabbit anti-rat immunoglobulin reagent. Anti-Thy-1-stimulated CD4-8- thymocytes were found to uniformly express CD3 but did not stain positively with F23.1, a mAb reactive with alpha/beta T cell receptors utilizing the V beta 8 gene family. Immunoprecipitation analysis of such stimulated CD4-8- thymocytes indicated that they expressed a CD3-associated heterodimer of 45 kDa/35 kDa most likely corresponding to the product of the gamma and (putative) delta T cell receptor genes. Taken together, these data demonstrate that anti-Thy-1 mAb selectively activate a subset of CD4-8- thymocytes committed to the gamma/delta T cell receptor lineage.

Immunochemical proof that a novel rearranging gene encodes the T cell receptor delta subunit

The T cell receptor (TCR) delta protein is expressed as part of a heterodimer with TCR gamma, in association with the CD3 polypeptides on a subset of functional peripheral blood T lymphocytes, thymocytes, and certain leukemic T cell lines. A monoclonal antibody directed against TCR delta was produced that binds specifically to the surface of several TCR gamma delta cell lines and immunoprecipitates the TCR gamma delta as a heterodimer from Triton X-100 detergent lysates and also immunoprecipitates the TCR delta subunit alone after chain separation. A candidate human TCR delta complementary DNA clone (IDP2 O-240/38), reported in a companion paper, was isolated by the subtractive library approach from a TCR gamma delta cell line. This complementary DNA clone was used to direct the synthesis of a polypeptide that is specifically recognized by the monoclonal antibody to TCR delta. This complementary DNA clone thus corresponds to the gene that encodes the TCR delta subunit.