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F Koning

Publications and source records attributed to F Koning.

At least 91 records · Page 5Linked to original sources
PubMed1990

Structural comparison of alpha/beta and gamma/delta T cell receptor-CD3 complexes reveals identical subunit interactions but distinct cross-linking patterns of T cell receptor chains.

Here we compare the subunit interactions within the alpha/beta and gamma/delta T cell receptor-CD3 (TcR-CD3) complexes. By using different detergent solubilization protocols, subunit interactions can be defined within such cell surface receptor complexes. It was found that in both TcR-CD3 complexes analogous subunit interactions can be defined: CD3 gamma and CD3 delta each form a stable complex with separate CD3 epsilon chains. Both the TcR gamma/delta and TcR alpha/beta form stable receptor complexes with these CD3 gamma/epsilon and CD3 delta/epsilon subunit. A zeta homodimer is present in these TcR-CD3 complexes. However, biochemical cross-linking results in a covalent bond between the CD3 gamma chain and the TcR beta chain in alpha/beta TcR-CD3 complexes and between the CD3 gamma chain and the TcR delta in gamma/delta TcR-CD3 complexes. This latter observation was independent of the type of TcR gamma/delta studied (e.g. disulfide or non-disulfide linked). These cross-linking results either indicate that the TcR beta and delta chains are each others structural homolog or that in TcR-CD3 complexes both TcR chains (alpha and beta, gamma and delta) are spatially closely associated with the CD3 gamma chain. The identical subunit interactions in the alpha/beta and gamma/delta TcR-CD3 complexes indicate no large structural differences between these receptor complexes but rather suggest a striking conservation of crucial interaction between subunits in the TcR-CD3 complexes.

Animals↗
PubMed1990

Analysis of early fetal T-cell receptor delta chain in humans.

In the mouse it has been found that a number of T-cell receptor (Tcr) gd phenotypes are generated during fetal thymic development. To examine whether such "waves" of Tcrgd phenotypes can be found in man, we studied the V-region usage and junctional diversity of the T-cell receptor delta chain in human fetal and post-partum thymocytes and peripheral blood T cells. Using the polymerase chain reaction (PCR)-amplification technique it was found that in fetal thymocytes of 15-17 weeks of gestation the Tcrd-V3 gene segment was mainly employed, whereas in post-partum thymocytes the Tcrd-V1 gene segment was preferentially used. These Tcrd-V3 transcripts contained only a single D element (D delta 3) and a limited random nucleotide insertion. The D delta 3 element was also present in Tcrd-V3-containing transcripts derived from peripheral blood gamma delta Tcr+ clones. These data suggest that a wave of Tcr gamma delta might exist early in human fetal development that preferentially use the Tcrd-V3 gene segment.

Base Sequence↗
PubMed1990

Gamma delta T-cell receptor repertoire in human peripheral blood and thymus.

T-cell clones expressing the gamma delta T-cell receptor (Tcr) were generated from peripheral blood lymphocytes (PBLs) and from a thymus sample. In the panel of ten thymus-derived clones, four gamma delta Tcr phenotypes [as defined by the reaction of monoclonal antibodies (mAbs) directed against known V gamma and V delta regions] were identified. All the clones lacked expression of the V delta 3 V region, while seven clones were V delta 1+. V delta 1 was found in combination with V gamma 9 or with undefined V gamma V regions. In addition, two other gamma delta Tcr phenotypes were identified on these clones: V gamma 9+V delta 1-V delta 3- and V gamma 9-V delta 1-V delta 3-. One of the clones expressed CD4 and another was CD8-positive. The remaining clones were CD4-CD8-. In the panel of 76 PBL-derived, gamma delta Tcr-bearing clones, five gamma delta Tcr phenotypes could be identified. In contrast to the thymus-derived clones, 30% of the clones were V delta 3+ whereas V delta 1 was expressed by a minority of the clones only. One clone was CD4-positive and approximately 30% of the clones were CD8-positive. Four of the five mAb-defined gamma delta Tcr phenotypes could be identified on both thymus and PBL-derived T-cell clones. However, biochemical analysis of the Tcrs demonstrates differences in the usage of C gamma 1- and C gamma 2-encoded gamma chains by T cells derived from the thymus and PBLs. The results therefore indicate that, at the clonal level, similarities and differences exist between the gamma delta Tcr repertoires expressed in the thymus and by PBLs. Furthermore, they indicate that combinatorial gamma delta Tcr heterogeneity is larger than has so far been described. The receptor diversity, combined with the potential of gamma delta Tcr+ cells to express CD4 or CD8, indicates that these cells are a heterogeneous population that might mediate a number of immune functions.

Antibodies, Monoclonal↗
PubMed1989

Murine T cells express a cell surface receptor for multiple extracellular matrix proteins. Identification and characterization with monoclonal antibodies.

Cell-cell and cell-extracellular (ECM) protein interactions are mediated through heterodimers termed integrins. We have demonstrated that dendritic epidermal T cell (DETC) lines adhere to the ECM proteins, fibronectin, fibrinogen, and vitronectin but not to collagen, laminin, or control proteins. This adhesion was blocked by the tetrapeptide RGDS, but not the control peptide, RGES. We have derived a hamster mAb H9.2B8, and a rat mAb, 8.18E12, from immunizations with DETC lines. The mAbs in combination, but not individually, specifically inhibited the adhesion of DETC lines to fibronectin, fibrinogen, and vitronectin. Immunoprecipitation analysis revealed that both mAbs reacted with a heterodimer composed of noncovalently linked 140- and 95-kD subunits. The 140-kD subunit can be reduced to 120- and 23-kD fragments. Although the two mAbs did not cross-compete for binding to DETC, sequential immunoprecipitation studies indicated that they react with the same 120-kD fragment. While all DETC cell lines and several T cell clones were reactive with the mAbs, the mAbs were not reactive with normal spleen, lymph node, thymus, or skin. Stimulation of splenic T cells with Con A or allogeneic cells induced mAb reactivity after 1 wk in vitro. These data demonstrate that a single lymphocyte receptor, with biochemical features characteristic of integrins, mediates RGD-dependent binding to the ECM proteins, fibronectin, fibrinogen, and vitronectin. Furthermore, since this integrin is expressed by long-term activated T cells, this receptor may play a physiological role in T cell function.

Animals↗
PubMed1989

Isolation of CD4- CD8- mycobacteria-reactive T lymphocyte clones from rheumatoid arthritis synovial fluid.

The majority of peripheral T cells express a heterodimeric, alpha/beta T-cell receptor, which recognizes specific antigenic peptides bound to self major histocompatibility complex (MHC) molecules, and either the CD4 or CD8 surface markers. An additional subset of T cells, whose physiological function is unknown, express a distinct CD3-associated receptor composed of gamma and delta chains. This subset includes cells lacking both CD4 and CD8 surface markers, which may be involved in autoimmunity. The recognition specificity of the gamma/delta receptors is not well characterized and has been defined in only one case to date, a murine cell line which shows MHC-linked specificity. In this report, we describe the isolation of CD4- CD8-, gamma/delta TCR bearing T cell clones from the synovial fluid of a rheumatoid arthritis patient. These T cell clones respond specifically to mycobacterial antigens without MHC restriction.

Arthritis, Rheumatoid↗
PubMed1989

Coordinated V gamma and V delta gene segment rearrangements in human T cell receptor gamma/delta+ lymphocytes.

Monoclonal antibodies (mAb) were used to characterize a panel (n = 46) of T cell receptor (TcR) gamma/delta+ T cell clones. Three of these antibodies have been described to react with specific variable region-encoded protein products and can therefore be used to detect functional gene rearrangements. The majority of peripheral blood-derived clones (43 out of 45) expressed the epitopes recognized by mAb BB3, encoded by the V delta 2 gene segment and mAb Ti gamma A, encoded by the V gamma 9 gene segment. These clones lacked the antigenic determinant recognized by mAb delta-TCS-1, encoded by the V delta 1 gene segment. The other two peripheral blood-derived clones and an ascites-derived clone were Ti gamma A-, BB3- and delta-TCS-1+. Biochemical analysis revealed that all Ti gamma A+, BB3+ T cell clones expressed the disulfide-linked form of the receptor. The two peripheral blood-derived delta-TCS-1+ T cell clones expressed the nondisulfide-linked form whereas the ascites-derived delta-TCS-1+ clone, AK119 expressed the disulfide-linked form of the TcR gamma/delta heterodimer. This indicates that V delta 1-encoded delta chains can be associated either with a C gamma 1- or a C gamma 2-encoded gamma chain. The preferential use of certain V gamma and V delta gene segments suggests the existence of a limited combinatorial diversity in TcR gamma/delta heterodimers, i.e. Ti gamma A+ (V gamma 9), BB3+ (V delta 2) and delta-TCS-1- disulfide-linked heterodimers and Ti gamma A-, BB3- and delta-TCS-1+ (V delta 1) disulfide- or non disulfide-linked forms.

Antibodies, Monoclonal↗
PubMed1989

Phenotypical heterogeneity among human T cell receptor gamma/delta-expressing clones derived from peripheral blood.

Human T cell clones expressing the T cell receptor (TcR) gamma/delta were isolated from peripheral blood lymphocytes of two unrelated donors. The TcR gamma/delta+ clones derived from one of these donors were all of the Ti gamma A+, delta-TCS1-, BB3+ phenotype indicating the exclusive use of the V gamma 9 and V delta 3 gene segments. In contrast, the T cell clones derived from the second donor were either Ti gamma A+, delta-TCS1-, BB3+:Ti gamma A-, delta-TCS1+, BB3- or Ti gamma A-, delta-TCS1-, BB3-. The delta-TCS1 determinant was expressed on both nondisulfide- and disulfide-linked TcR gamma/delta. Northern blot and DNA sequence analysis indicated that the Ti gamma A-, delta-TCS1-, BB3- clones do use the V delta 1 gene segment demonstrating that the delta-TCS1 monoclonal antibody does not react with all TcR gamma/delta using this particular gene segment. In contrast to the delta-TCS1+ T cell clones, the V delta 1+ delta-TCS1- T cell clones were found to express V delta 1 in conjunction with the J delta 3 gene segment suggesting that this particular V delta 1-J delta 3 combination is not recognized by the delta-TCS1 monoclonal antibody. In T cell clones derived from one individual the V delta 1 gene segment was found to be expressed with either J delta 1, J delta 2 or J delta 3. Heterogeneity among the 18 clones was detected with respect to the expression of the CD4, CD5 and CD8 antigens: one clone was CD4+, nine clones were CD5+ and two clones were CD8+. Thus, in this panel of clones, heterogeneity exists both with regard to CD antigen expression and the TcR gamma/delta phenotype. Also, our results indicate that the delta-TCS1 monoclonal antibody does not react with all TcR gamma/delta using the V delta 1 gene segment.

Antibodies, Monoclonal↗
PubMed1989

A novel T-cell-defined HLA-DR polymorphism not predicted from the linear amino acid sequence.

Recent investigations have shown that alloreactive T cells are capable of responding to structures defined by specific linear amino acid sequences on class II molecules. In the present study we show that also a polymorphism can be recognized that is not defined by such linear amino acid sequences. Two human T-cell clones, sensitized to DRw13 haplotypes, are described. The description of clone c50 serves to exemplify the first model. This DRB1-specific clone responds to stimulator cells that carry DR molecules, different in their DRB1 first and second hypervariable regions (HV1 and HV2) but identical in their HV3 regions (i.e., DRw13,Dw18; DRw13,Dw19; DR4,Dw10; and DRw11,LDVII). The second clone, c1443, behaves nonconventionally. It responds to DRw13,Dw18; DRw13,Dw19; and DR4,Dw4 stimulator cells, although no specific amino acid sequence is shared between these specificities. The latter pattern of reactivity suggests the existence of a novel polymorphism recognized by alloreactive T cells. This particular polymorphism may also be biologically significant.

Amino Acid Sequence↗
PubMed1988

Expression of C gamma 4 T cell receptors and lack of isotype exclusion by dendritic epidermal T cell lines.

Although four murine C gamma gene segments (C gamma 1, 2, 3, and 4) are known to exist, the large majority of expressed gamma-chains have been shown to be of the C gamma 1 isotype and no evidence exists for the expression of more than one receptor by gamma delta TCR-bearing cells. We investigated the nature of the TCR expressed on a number of murine dendritic epidermal T cell-derived cell lines by using both Northern blot and immunoprecipitation analyses. One of these CD3+ cell lines (T195) expresses C gamma 4, V gamma 1, and delta mRNA, and its CD3-associated TCR complex can be precipitated by both anti-C gamma 4 and anti-delta sera, indicating that this receptor is a C gamma 4/delta heterodimer. Furthermore, we show that two cell lines (Y245, Y93) express two distinct TCR gamma-chains, one derived from the C gamma 4 locus, whereas the second gamma-chain is probably derived from the C gamma 2 locus. Together with the previous demonstration of C gamma 1/delta TCR on a number of dendritic epidermal T cell lines (DETC), these results indicate that such DETC are capable of expressing a variety of gamma delta TCR and that, in some DETC, isotype exclusion of gamma-chain expression does not occur.

Animals↗
PubMed1988

Peripheral murine CD3+, CD4-, CD8- T lymphocytes express novel T cell receptor gamma delta structures.

A mAb directed against the CD3 molecule was used to identify a subset of CD3+, CD4-, CD8- T cells previously undefined in the peripheral lymphoid organs of the mouse. Biochemical analysis of CD3+, CD4-, CD8- splenocytes revealed that the vast majority of these cells express one of at least two distinct CD3-associated TCR gamma delta heterodimeric structures, but no detectable TCR alpha beta. One disulfide-linked heterodimer (77 kDa) is composed of two chains of 45 to 46 and 32 kDa. The latter chain was immunoprecipitated with an anti-TCR C gamma 1/C gamma 2 antiserum and was not glycosylated. An antiserum produced against a peptide corresponding to the C-terminal region of the predicted C gamma 4 gene product immunoprecipitated additional heterodimers (80 to 90 kDa). One heterodimer, composed of disulfide-linked 41- to 45-kDa protein (including a V gamma/C gamma 4 component), is expressed on a T cell hybridoma, DN-1.21, which was derived from fused splenic CD3+, CD4-, CD8- T cells. Another V gamma/C gamma 4-containing heterodimer is composed of disulfide-linked 46- to 47-kDa glycoproteins. These findings demonstrate that CD3+, CD4-, CD8- T cells present in the peripheral lymphoid organs express a variety of paired TCR gamma delta proteins. Unlike CD3+, CD4-, CD8- thymocytes, these cells express high levels of C gamma 4, but little, if any TCR alpha beta.

Animals↗
PubMed1988

Characterization of a cell surface-expressed disulfide-linked dimer involved in murine T cell activation.

We have produced a hamster mAb, H1.2F3, which was derived by immunization with a murine TCR-gamma delta + epidermal T cell line. H1.2F3 immunoprecipitates a cell surface-expressed disulfide-linked dimer that has a m.w. of 85,000 under non-reducing conditions and consists of subunits of 35,000 to 39,000 m.w. This dimer is distinct from the CD3-associated TCR-gamma delta complex (CD3/TCR), inasmuch as H1.2F3 does not co-precipitate or co-modulate with the CD3/TCR complex and recognizes an Ag with a single-peptide backbone of 22,000 m.w. after N-Glycanase treatment. H1.2F3 is weakly reactive with a small percentage of cells from unfractionated thymus, spleen, or lymph node, but reactivity with both T and B lymphocytes is markedly enhanced by a brief period of stimulation with Con A or PMA in vitro. This enhancement requires de novo protein synthesis. Enhanced expression of the H1.2F3 Ag can also be induced in vivo by injection of Con A or anti-CD3. H1.2F3 is a potent stimulator of T, but not B, cell proliferation in the presence of PMA and FcR-bearing accessory cells. These functional and biochemical studies strongly suggest that the Ag recognized by H1.2F3 is the murine homologue of the human CD28 Ag recognized by mAb 9.3.

Aging↗
PubMed1988

The biosynthesis and assembly of T cell receptor alpha- and beta-chains with the CD3 complex.

The biosynthesis, processing, and assembly of the TCR alpha- and beta-chains with each other and with the CD3 complex were investigated on both cell surface positive (TCR+CD3-) and negative (TCR-CD3-) cell lines. The results indicate that 1) in cell surface TCR-CD3- cell lines (MOLT 3, CCRF-CEM), TCR-beta, but not alpha-chains are present intracellularly. TCR-beta-CD3 complexes are readily found in these cell lines, but no evidence for final processing or cell surface expression of such incomplete TCR-CD3 complexes is observed. 2) In the cell surface TCR+CD3+ cell line HPB-ALL, both alpha- and beta-chains are present intracellularly. Whereas non-glycosylated forms of TCR-beta chain can be detected, only more mature forms of TCR alpha-chains are detected indicating that the alpha-chains are more rapidly glycosylated than the beta-chains. 3) The large majority of the intracellular alpha- and beta-chains is not disulfide linked and a small fraction of these is associated with CD3. 4) Only small amounts of the total intracellular TCR chains are found as CD3-associated disulfide-linked alpha beta-heterodimers. 5) Final processing of TCR chains for cell surface expression takes place after formation of these TCR-alpha beta-CD3 complexes. Thus, both the TCR alpha- and beta-chains are over-produced and only relatively small amounts of these chains form CD3-associated heterodimers that are processed for cell surface expression. Analogous results were obtained with a non-leukemic CTL clone. Based on these observations, a model for the biosynthesis and assembly of the TCR-CD3 complex is presented.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1988

T cell receptor gamma/delta chain diversity.

The TCR-gamma and -delta chains of six murine hybridomas were compared by one-dimensional SDS-PAGE and two-dimensional NEPHGE/SDS-PAGE analysis. This allowed the identification of three distinct gamma chains (gamma a, gamma b, and gamma c) and three distinct delta chains (delta a, delta b, and delta c). Four gamma/delta chain combinations (gamma a delta a, gamma b delta b, gamma b delta c, and gamma c delta a) were observed. These results indicate that multiple forms of the delta chain are expressed and suggest that the delta chains are encoded for by an Ig-like rearranging gene. This delta chain polymorphism significantly enhances the potential diversity of TCR-gamma/delta, which may be of importance for a better understanding of the putative ligand(s) recognized by this receptor.

Animals↗
PubMed1988

Characterization of T cell receptors on resident murine dendritic epidermal T cells.

Cell lines derived from Thy-1+ dendritic epidermal cells (Thy-1+DEC) display a marked heterogeneity in T cell receptor (TcR) expression including CD3-associated alpha/beta, C gamma 1/delta or C gamma 2/delta and C gamma 4/delta TcR. In order to investigate whether this heterogeneity is primarily imposed by in vitro culture conditions or, alternatively, is already present within the epidermis, we studied TcR expression by Thy-1+DEC in situ and on freshly isolated epidermal cell suspensions greatly enriched for Thy-1+DEC. Immunolabeling experiments showed that resident Thy-1+DEC are CD45+, Thy-1+, CD3+, TcR V beta 8-, CD5-, CD4- CD8-, CD25- lymphocytes. Immunoprecipitation of lysates from 125I-surface-labeled Thy-1+DEC-enriched epidermal cells with anti-CD3 epsilon, anti-C gamma 1,2,3 and anti-C gamma 4 antibodies, respectively, and subsequent analysis of the precipitates by two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed only CD3-associated 35 kDa/45 kDa gamma/delta heterodimers. The demonstration of TcR heterodimers on resident Thy-1+DEC strongly implies that these cells are functional T cells. The selective expression of C gamma 1/delta (C57BL/6) and C gamma 1/delta or C gamma 2/delta (C3H/He) TcR makes these cells useful for the study of gamma/delta TcR function.

Animals↗
PubMed1988

Functional polymorphism of the HLA-DR beta III chain.

Several clusters of class II HLA genes contribute to variation in human antigen-presenting capacity. In the HLA-DR cluster, most of the variation is due to the highly polymorphic DR beta I gene. Recent work by others has shown some nucleotide and implied amino acid sequence variation in DR beta III chains, but this variation is not known to be functionally significant. We show here that two proliferating human T-cell clones define three allelic variants of DR beta III (assignment to DR beta III based on blocking of proliferation by selected monoclonal antibodies). Thus, the DR beta III locus encodes at least three alleles that are distinguishable by human T cells and most probably contribute to the human antigen-presenting repertoire. The three DR beta III alleles subdivide the "supertypic" HLA antigen DRw52 into subtypes provisionally called DRw52.1-52.3. The DR3 haplotypes studied to date have been either DRw52.1 or 52.2; DR5 haplotypes have all (23 of 23) been 52.2; DRw6 haplotypes have included all three DRw52 subtypes, nearly half being 52.3. Our data, combined with other published data, imply that DRw8 must either have a fourth DRw52 subtype or be DR beta III null.

Alleles↗