Biomedical subjects

F Koning

Publications and source records attributed to F Koning.

At least 109 records · Page 6Linked to original sources

PubMed1987

Independent association of T cell receptor beta and gamma chains with CD3 in the same cell.

We have demonstrated that the PEER cell line, which expresses a CD3-associated TCR gamma chain on the cell surface, synthesizes TCR beta chain intracellularly. A percentage of this TCR beta chain associates with the CD3 complex intracellularly. These results indicate that TCR beta and gamma chains can be synthesized by one cell line, and that these chains can independently associate with the CD3 complex. However, the results argue against the formation of TCR beta gamma chain complexes in this cell line.

Antigens, Differentiation, T-Lymphocyte↗

PubMed1987

Production of a T cell hybridoma that expresses the T cell receptor gamma/delta heterodimer.

We have produced a T cell hybridoma line by fusion of an IL-2-dependent, long-term T cell receptor (TCR) gamma/delta+ Thy-1+, bone marrow-derived, dendritic epidermal cell line to the BW5147 tumor line. The resultant hybridoma was rapidly growing, lymphokine independent, and expressed T3 in association with the TCR gamma/delta heterodimer. Several subclones of the hybridoma line produced easily detectable levels of IL-2 after stimulation by anti-T3 or Con A. The availability of these cloned cell lines should greatly facilitate further functional, biochemical, and molecular studies of the TCR delta chain.

Animals↗

PubMed1987

Identification of a T3-associated gamma delta T cell receptor on Thy-1+ dendritic epidermal Cell lines.

The murine epidermis contains a subpopulation of bone marrow-derived lymphocytes that have a dendritic morphology and that express Thy-1 and T3 cell-surface antigens but not other markers (L3T4 or Lyt-2) characteristic of mature peripheral T lymphocytes. An alternative type of T cell receptor was earlier identified on a subpopulation of murine thymocytes with a similar phenotype (T3+, L3T4-, Lyt-2-), but not on peripheral murine T lymphocytes. Two independently derived Thy-1+, L3T4-, and Lyt-2- dendritic cell lines of epidermal origin that express a T3-associated disulfide-linked heterodimer composed of a 34-kilodalton gamma-chain and 46-kilodalton partner (the delta chain) have now been identified. Analysis of N-linked glycosylation revealed that this receptor is similar to that detected on thymocytes. These results demonstrate that Thy-1+ dendritic epidermal cell lines can express gamma delta T cell receptors in vitro and suggest that Thy-1+ dendritic epidermal cells express such receptors in vivo. The localization of these gamma delta T cell receptor-expressing cells in the epidermis may be of importance for understanding the function of these receptors.

Animals↗

PubMed1987

Expression of the human T cell receptor as defined by anti-isotypic antibodies.

Anti-isotypic reagents against the human T cell receptor (TcR) were made by immunizing rabbits with peptides which corresponded to sites within the constant region of the alpha- and beta-chains. These antibodies were shown to immunoprecipitate a heterodimer of 80,000 to 90,000 m.w. that could be reduced to chains of 44,000 to 50,000 and 37,000 to 40,000 m.w. In addition, an anti-peptide serum against CD3 delta-chain was made. The anti-alpha peptide serum reacted with all human TcR (from phytohemagglutinin-stimulated lymphocytes, cytotoxic T cell clones, and the T cell leukemias: HPB-ALL, Jurkat, JA3, and JM), and the anti-beta peptide serum reacted with only human TcR of the C beta 2 isotype (from a cytotoxic T cell clone which had a C beta 2 transcript, HPB-ALL, and a proportion of phytohemagglutinin-stimulated lymphocytes, but not with Jurkat, JA3, and JM). A comparison of the detergents NP-40 and digitonin revealed that digitonin was more efficient at keeping the TcR/CD3 complex intact, but was less efficient at solubilizing the total amount of TcR or the total amount of CD3. With these reagents and the use of digitonin, it was shown that all of the alpha, beta, and CD3 moieties on the surface of a T cell leukemia HPB-ALL occur as a bound TcR/CD3 complex. The proportion of C beta 1 to C beta 2 isotype expressed on the surface of phytohemagglutinin-stimulated peripheral blood lymphocytes was 0.8, indicating approximately equal use of the two beta-chain isotypes.

Animals↗

PubMed1987

Phenotypical and functional analysis of B lymphocytes of two siblings with combined immunodeficiency and defective expression of major histocompatibility complex (MHC) class II antigens on mononuclear cells.

Phenotypic and functional analysis of B lymphocytes in two siblings with combined immunodeficiency associated with defective expression of class I and class II major histocompatibility complex (MHC) antigens on mononuclear cells is described. The results of the analysis of the membrane phenotype of the B cells performed at the age of 1 and 5 years, respectively, by the use of monoclonal antibodies against class I (HLA-A, -B, -C) and class II (HLA-DR, -DP, -DQ) MHC antigens showed a decreased expression of class I antigens and a complete lack of class II antigens. Class I antigen expression consistently remained of the same magnitude during follow-up. Class II antigen expression remarkably had been positive early in life on B cells and activated T cells, whereas monocytes were negative for class II from birth onward. B lymphocytes of both patients responded in vitro to polyclonal activation with Staphylococcus aureus Cowan I staphylococci (SAC) with the production of IgM-type immunoglobulins only. This neonatal type of response was in agreement with the membrane immunoglobulin phenotype of the B cells since a high sIgM/sIgD ratio characteristic of neonatal B cells was present. However, the expression of the FMC7 antigen on B cells of both patients was comparable to that on B cells of normal adults. We hypothesized that the lack of MHC antigen expression may impose a resting state on the lymphocytes in these patients due to ineffective cellular interactions. In this view the high sIgM/sIgD ratio reflects the activation state of the B cells rather than the maturational state of the cells.(ABSTRACT TRUNCATED AT 250 WORDS)

B-Lymphocytes↗

PubMed1987

Molecular localization of LB-Q1, a DRw52-like T-cell recognition epitope and identification at the genomic level of associated shared hybridizing fragments.

In this paper we report on the molecular localization of LB-Q1, a supertypic HLA class II determinant which we previously identified by the use of proliferative T cells. The population distribution shows that each of the DRw52 associated specificities DR3, DR5, and DRw6 may occur with and without LB-Q1. DNA from nine DR3, six DR5, and 14 DRw6 homozygous B-cell lines were digested with the enzymes TaqI, EcoRI, and PvuII. Using a DR beta cDNA probe, shared hybridizing fragments were observed that correlate completely with the presence or absence of LB-Q1. T-cell recognition of LB-Q1 can be blocked with a monoclonal antibody (7.3.19.1) which in some haplotypes selectively reacts with the DR beta III chains, but cannot be blocked with a monoclonal antibody (I-LR2) reacting in those same haplotypes exclusively with DR beta I chains. Therefore, LB-Q1 maps to the DR beta III molecule. These data suggest the occurrence of relatively frequent previous recombinations between the two DR beta chain genes present in DRw52 haplotypes.

Antibodies, Monoclonal↗

PubMed1987

Thy-1+ dendritic epidermal cells express T3 antigen and the T-cell receptor gamma chain.

The murine epidermis is a heterogeneous epithelium composed of keratinocytes, melanocytes, Langerhans cells, and a recently described subpopulation (2-3%) of bone-marrow-derived leukocytes with a dendritic morphology and the cell surface phenotype Thy-1+, L3T4-, Lyt-2-. Previous studies have demonstrated that cell lines derived from freshly explanted Thy-1+ dendritic epidermal cells (DEC) have abundant mRNA for rearranged T-cell receptor (TCR) gamma-chain genes. Analysis of Thy-1+ DEC in situ, freshly isolated cell suspensions of Thy-1+ DEC, and long-term Thy-1+ DEC lines demonstrated that 100% of the Thy-1+ DEC reacted with a monoclonal antibody to the epsilon chain of the murine T3 complex and that 40-60% of resident Thy-1+ DEC were also reactive with an antiserum to the TCR gamma chain. Two Thy-1+ DEC lines expressed a disulfide-linked 70-kDa molecule that could be precipitated with an anti-gamma-chain antiserum and could be coprecipitated with an antiserum to the T3 delta chain; the molecule appeared as a single 34-kDa band under reducing conditions. The phenotype of Thy-1+ DEC (T3+, L3T4-, Lyt-2-, TCR gamma chain+) thus resembles that of the recently described subpopulation of murine and human lymphocytes that have been identified in the thymus, peripheral blood, and fetal blood.

Animals↗

PubMed1987

Differential expression of DRw52-like determinants detected by monoclonal antibodies.

The reactivity of three monoclonal antibodies (MoAb) directed against DRw52-like determinants was studied in relation to the reactivity of an anti-DR MoAb using fluorescence-activated cell sorter (FACS) analysis. The MCS-7 MoAb reacted with all DRw52+ cells and in addition with DR2+, DR4+, and a DR7+ cell. Both the I-LR2 and the 7.3.19.1 MoAb reacted with DR3+, DR5+, and DRw6+ cells only. However, whereas the 1-LR2 MoAb reacted strongly with all those cells compared with the anti-DR MoAb, the 7.3.19.1 MoAb reacted strongly with DR3+ cells only, and somewhat less with DR5+ and DRw6+ cells. The implications of this for the location of DRw52-like determinants on DR beta chains is discussed.

Antibodies, Monoclonal↗

PubMed1986

T90/44 (9.3 antigen). A cell surface molecule with a function in human T cell activation.

T90/44 is a cell surface antigen which is present on human T cells of the helper and cytotoxic subsets and which binds the 9.3 monoclonal antibody (9.3 mAb). It is expressed in the form of 90-kDa disulfide-bonded dimers of a 44-kDa polypeptide and of free 44-kDa subunits. The function of T90/44 was investigated in a series of T cell function assays. 9.3 mAb was found to inhibit the activation of class II-restricted cloned T helper cells derived from leprosy patients and reactive with M. leprae antigens. The inhibition was first found at 1-10 ng/ml 9.3 mAb and regularly increased with the antibody concentration. The extent of the inhibition varied among different T cell clones in proportion to the respective different levels of T90/44 expression at their cell surface. The proliferative responses of peripheral blood lymphocytes (PBL) to purified protein derivative of M. tuberculosis (PPD) and tetanus toxoid were enhanced by the 9.3 mAb resulting in up to 20-30-fold increase of [3H]-thymidine incorporation. After phytohemagglutinin-induced activation of PBL, the number of T90/44 molecules per cell expressed at the cell surface rose from day 0 to day 7 by a factor of about 10. High concentrations of 9.3 mAb (5-10 micrograms/ml) at low cell densities and in the presence of monocytes in culture media supplemented by fetal calf serum were directly mitogenic for resting lymphocytes. The cytolytic effector functions of class I-restricted cytotoxic T lymphocytes (CTL) were not modulated by 9.3 mAb. The mixed lymphocyte reactions of three class I-restricted CTL to their specific target cells were found not to be significantly influenced by 9.3 mAb. In conclusion it is proposed that an antigen-independent T cell activation pathway can be entered at T90/44.

Antibodies, Monoclonal↗

PubMed1986

Divergent and invariant HLA class II beta chain isoelectric points.

Class II molecules were isolated from consanguineous HTCs (DR1-DRw8) by sequential immunoprecipitation with the monoclonal antibodies 7.3.19.1 (anti-DRw52-like), B8.11.2 (anti-DR backbone), and 7.5.10.1 (anti-HLA class II backbone). Depending upon the DR-serotype of the cell line used, two or three class II antigen families, distinct in molecular weight, could be isolated (see Hum Immunol 9:221, 1984). Immunoprecipitated class II molecules were treated with NaNase and then analyzed on 1D-IEF gels. Each HLA class II antigen family contained two alpha chains conserved in pI. Furthermore, the various haplotypes show distinct electrophoretic beta chain patterns. The number of beta chain charge configurations detected varies from 2 to 5, depending upon the antigen family or haplotype studied. Some of these chains have a pI which is specific for a given class II serotype whereas other beta chain pIs are invariant and shared among more antigen families or haplotypes.

Antibodies, Monoclonal↗

PubMed1986

TA10 and 2B3, two new alleles in the HLA-DQ region recognized by monoclonal antibodies.

The monoclonal antibodies (MoAbs) A10/13 and IIB3 were studied in parallel with routine HLA-DR typings. The specificities TA10 and 2B3, recognized by A10/13 and IIB3 MoAb, respectively, showed clear segregation in families and never occurred together on the same haplotype. TA10 and 2B3 appeared to be in perfect Hardy-Weinberg equilibrium. The TA10 specificity is DQw3 related and is in linkage disequilibrium with DR5 (DRw11 and DRw12) and it is also weakly associated with DR4. The 2B3 specificity is DQw1 related and it is in linkage disequilibrium with DR2, DR4, DRw9, and DRw13. The 2B3 and TA10 specificities appear to be alleles of a polymorphic system, closely related, but different from HLA-DQ.

Alleles↗

PubMed1986

Identification of a new lymphocyte subset surface antigen, the expression of which disappears after in vitro and in vivo stimulation. Distribution, biochemistry, and functional studies.

Two monoclonal antibodies (MoAbs) are described (MD 2.6, IgG1 and MD 4.3, IgG2a) that react with a nonlineage specific lymphocyte subset surface antigen. This antigen is expressed on B cells, a subset of both T8+ and T4+ cells, cells that exert killer and natural killer cell activity in vitro, B cells in lymph nodes, and a small percentage of thymocytes. Expression of the antigen was found to be variable on T cells but not on B cells among individuals. Following polyclonal activation, expression of the determinant detected was lost from the cell surface. Both MD+ and MD+ cells responded to PHA and in MLC. MLC resulted in the generation of cytotoxic T lymphocytes and primed T lymphocytes in both the MD+ and MD+ subpopulations. In contrast, the response to soluble antigens was found to reside almost exclusively in the MD-subset. Immunoprecipitation indicates that the MoAbs react with an antigen that has a molecular weight of 220-240 KD which can be cleaved into subunits of 70-80 kD by beta-mercaptoethanol.

Antibodies, Monoclonal↗

PubMed1986

Multiple epitopes on a single DQ molecule from the DQw3-carrying haplotypes.

Multiple polymorphisms on the DQ molecule(s) have been detected by monoclonal antibodies (MoAbs). Among these, TA10 and IIB3 have been described as two new alleles in the DQ region other than the conventional DQw1-w3 allelism. The TA10 specificity is DQw3-related and is in linkage disequilibrium with DR5 and weakly associated with DR4. The IIB3 specificity is DQw1-related and is in linkage disequilibrium with DR2, DR4, DRw9 and DRw13. Thus, the DQw3-carrying haplotypes are either positive with TA10 or IIB3. The molecular and topological analysis has revealed that both TA10 and IIB3 determinants were expressed on a single DQ molecule that also carried the DQw3 determinants on DR5 and DR4 cell lines, respectively. Thus, a single DQ molecule generated multiple epitopes detected by alloantisera and/or MoAbs at least on the DQw3-carrying haplotypes. These would be useful for unraveling the largely unknown functions of the DQ class II molecules.

Antibodies, Monoclonal↗

PubMed1986

Antibody dependent cellular cytotoxicity mediated by HLA-class II specific monoclonal antibodies.

The ability of mouse monoclonal antibodies (MoAbs) directed against HLA-class II molecules to mediate in Antibody Dependent Cellular Cytotoxicity (ADCC) was investigated. The results indicate that both MoAbs to monomorphic and polymorphic HLA-DR and DQ determinants are able to mediate ADCC in an antigen specific manner. However, not all antibodies mediate ADCC to a similar extent. Furthermore, antibodies were identified that appeared to mediate ADCC in an HLA-DR haplotype dependent fashion. These results indicate that the inhibition of HLA-class II specific proliferative responses by anti-class II MoAbs may be influenced by ADCC directed against class II positive stimulator cells.

Animals↗

PubMed1986

Selective removal of clonogenic neoplastic B cells from human bone marrow using anti-HLA-DQ antibodies and complement.

Polymorphic HLA-DQ (DC/MB) determinants appeared to be not expressed on human hematopoietic progenitor cells (HPC), using several murine monoclonal and human polyclonal antibodies in a complement-dependent cytotoxicity (CDC) assay. Since mature HLA-DR-positive malignant lymphoma cells prove to be HLA-DQ positive, an attempt was made to remove clonogenic neoplastic DQwl-positive B cells selectively from DQwl-positive marrow samples without affecting hematopoietic progenitor cells. Using a combination of a clonogenic tumor cell assay, an HPC culture assay, and a mixed-tumor-cell-HPC culture assay, selective elimination of more than 98% of clonogenic neoplastic cells from tumor-cell-contaminated bone marrow suspensions was achieved with monoclonal anti-DQ antibodies and complement without depletion of HPC. These results indicate that anti-HLA-DQ antibodies can be used in autologous bone marrow transplantation to deplete the bone marrow cell suspension of DQ-positive malignant cells.

Antibodies, Monoclonal↗

PubMed1986

Expression of CD11, CDw15, and transferrin receptor antigens on human hematopoietic progenitor cells.

The expression of transferrin receptor-associated antigens and of CD11 and CDw15 antigens was investigated on myeloid committed progenitor cells (CFU-GM day 10, CFU-GM day 7, and cluster-forming cells [CFC] day 4), on erythroid committed progenitor cells (BFU-E and CFU-E), and on multilineage progenitor cells (CFU-GEMM). Both complement-dependent cytotoxicity and fluorescence-activated cell-sorting assays were performed. Complement-dependent cytotoxicity appeared to be the more sensitive assay. Transferrin receptor-associated antigens appeared to be clearly present on all myeloid and erythroid committed progenitor cells, but were found to be only weakly expressed on CFU-GEMM. CD11 antigens appeared to be strongly expressed only on mature granulocytes, monocytes, and certain lymphocytes, but not significantly on myeloid committed precursor cells. Surprisingly, CD11 antigens were weakly, but significantly, present on CFU-E. CDw15 antigens appeared to be restricted to myeloid differentiation and were increasingly expressed from CFU-GM day 10 to CFC day 4. Thus, antitransferrin receptor, CD11, and CDw15 antibodies can be used to separate hematopoietic progenitor cells and may be useful tools in the study of hematopoietic differentiation.

Antibodies, Monoclonal↗

PubMed1985

Typing for HLA class II at the product level.

Class II antigens were isolated from consanguineous homozygous typing cells by sequential immunoprecipitation with the MoAbs: 7.3.19.1 (anti-DRw52-like), B.8.11.2 (anti-DR backbone) and 7.5.10.1 (anti-HLA class II backbone). Depending on the DR serotype of the cell line used, two or three families of class II antigens could be isolated [1]. For each homozygous typing cell the different families of class II antigens were analysed on 1D-IEF gels. Charge heterogeneity showed that the different haplotypes are distinct in electrophoretic beta chain patterns. For each homozygous typing cell at least one beta chain was observed that possessed a haplotype unique pI. This means that typing for HLA class II at the product level is possible.

Antibodies, Monoclonal↗

PubMed1985

HLA class II restriction repertoire of antigen-specific T cells. II. Evidence for a new restriction determinant associated with DRw52 and LB-Q1.

We have studied the HLA class II restriction repertoire of antigen-specific T lymphoblasts (T-LB) in response to purified protein derivative (PPD) and tetanus toxoid (TET), presented by allogeneic antigen-presenting cells (APC). In 102 fully DR(1-w14) mismatched T-LB/APC combinations matching for DRw53 (MT3) had a significant influence on T-LB proliferation (p = 0.0005). Moreover, the supertypic specificity DRw52 (MT2) and LB-Q1 (a new class II determinant in strong linkage disequilibrium with DRw52) appeared to be markers for a new RD (p less than 0.0005). LB-Q1 was most strongly associated with this RD and among DRw52 identical T-LB/APC combinations additional LB-Q1 sharing significantly increased T-LB responsiveness (p = 0.02). DRw52- and LB-Q1-restricted responses could be inhibited by an anti-DRw52 and an anti-DR framework monoclonal antibody, indicating that DR(w52), LB-Q1, and the new RD are located at the same molecule.

Antibodies, Monoclonal↗