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M Nĕmec

Publications and source records attributed to M Nĕmec.

11 recordsLinked to original sources
PubMed1990

Ontogeny of MHC class II antigens in pigs.

Cells constitutively expressing MHC class II antigens have been studied in the course of prenatal development in the Minnesota miniature pig. Frozen sections, cell suspensions and peripheral blood mononuclear cells were examined by using the HL-40 monoclonal antibody cross-reactive with a light chain determinant of the SLA-D molecule (MHC class II porcine antigen). It could be demonstrated that the yolk sac contained cells expressing SLA-D antigens as early as the 24th day, the liver and the spleen on the 39th day of gestation. Splenic cells bearing SLA-D molecules formed periarteriolar structures. Except the spleen, peripheral blood, lymph nodes, bone marrow and intestinal wall were the main sites of SLA-D expression in the perinatal period of the pig.

Animals↗
PubMed1989

Detection of blood group A antigen expression in human colon cancer using monoclonal antibodies with different specificities.

Blood group antigen expression in human colon cancer was studied by means of two monoclonal antibodies of broad anti-A (HE-14) and anti-type 3 and type 4 chain-based A and H (HE-10) specificity. These antigens were proved to reappear in tumors of the distal colon, the HE-10 antibody reacting more frequently (9 out of 12 samples) than HE-14 (5 out of 12 samples) and frequently with supranuclear staining of the cytoplasm probably in those places of the Golgi apparatus where carbohydrate antigens are synthesized. This staining pattern is characteristic of HE-10 in normal colonic mucosa as well. With HE-14, staining was often absent in less differentiated tumors, while HE-10 did react in such tumors. In this connection, the possible expression of type 3 and type 4 chain H antigens in the tumor tissue is discussed. In some cases, these two antibodies gave different staining patterns in parallel sections from the same tissue sample, primarily at the cellular level. Three out of 12 cases showed blood group antigen expression in the mucosa of the distal colon adjacent to the tumor only when HE-10 antibody was used.

ABO Blood-Group System↗
PubMed1988

Expression of MHC class II antigens and immunoglobulins in immunized pig foetuses.

Pig foetal spleen, liver and thymus cells were examined by using polyclonal antibody to pig immunoglobulins and monoclonal antibody reacting with a light chain determinant of pig MHC class II antigens. Pig foetuses were immunized with flagellin on the 72nd day of prenatal life. On the 14th day following antigen administration, large numbers of class II antigen-bearing cells and Ig-containing cells were demonstrated in the spleen using the immunofluorescence technique. Topographical localization of these cells in cryostat sections was very similar.

Animals↗
PubMed1987

Murine monoclonal antibodies to human A erythrocytes: differential reactivity with N-acetyl-D-galactosamine.

Six different hybridoma cell lines were obtained producing IgM monoclonal antibodies (MAbs) against human blood group A antigen. All these MAbs agglutinate the A1, A1B and A2 erythrocytes, while only one of them agglutinates the A2B erythrocytes. The agglutination activity of 3 of these MAbs is inhibited by N-acetyl-D-galactosamine (D-GalNAc). Dissociation constants of complexes of these MAbs with D-GalNAc are approximately 2.2 X 10(-3) mol/l.

ABO Blood-Group System↗
PubMed1987

Limited enzymatic cleavage of pig immunoglobulin and of specific antibodies. V. Monoclonal antibodies to individual fragments and polypeptide chains.

Six hybridomas that produce monoclonal antibodies to different antigenic determinants of heterogeneous pig IgG and of pig anti-Dnp antibodies were obtained by fusion between spleen cells from BALB/c mice immunized with non-specific pig IgG and the myeloma line P3-X63-Ag8.653. Antigenic determinants which correspond to individual monoclonal antibodies were located in the individual domains of the IgG molecule by investigating the interaction of monoclonal antibodies with Fab, Fc, and pFc' fragments and with kappa, lambda, and gamma polypeptide chains. To evaluate the interaction, a quantitative equilibrium competitive radioimmunoassay was developed and [14C]formaldehyde-labelled non-specific pig IgG served as labelled antigen. Antibodies PGG-01, PGG-04, and PGG-06 were shown to be directed against determinants in the C lambda domain, antibody PGG-03 very probably against the determinant in the C chi domain, and antibodies PGG-02 and PGG-05 against determinants in the CH3 domain. Antibodies PGG-02 and PGG-05 are highly selective for IgG subpopulations; when combined, they interact with no more than 42% of the heterogeneous IgG population. These two antibodies can be used as a basis for preparing a complete set of reagents for identification of individual subclasses.

2,4-Dinitrophenol↗
PubMed1987

HLA-DQ1 + DQ3-specific monoclonal antibody cross-reacts with a rat MHC-encoded polymorphic determinant.

From a panel of seven mouse monoclonal antibodies against human class II molecules only one, HL-37, directed against the beta chain of human DQ1 and DQ3 antigens cross-reacted in membrane immunofluorescence with the RT1b haplotype of the rat major histocompatibility complex. From the results obtained using an indirect immunoprecipitation method with 35S- and 125I-labelled rat samples from RT1b-carrying lymph node cells it can be supposed that the rat homologue of the human DQ beta chain was detected.

Animals↗
PubMed1986

Characterization of seven new monoclonal antibodies against human DR, DR + DP and DQ1 + DQ3 antigens.

Seven murine monoclonal antibodies were prepared that react with human class II antigens. Four of them (HL-39, MEM-12, MEM-24G, and MEM-32B: react with a monomorphic determinant dependent on association of heavy and light chains of DR antigens, two others (HL-38 and HL-40) recognize a monomorphic determinant localized on the light chains of DR and DP antigens. The antibody HL-37 is directed against a determinant present on DQ1 and DQ3, but not DQ2 molecules; at least in the case of DQ1, the epitope recognized is located on the light chain.

Animals↗
PubMed1979

Dissociation of the proliferative and effector non-H-2 minor histocompatibility-alloimmune responses.

The first-set and second-set allotransplantation reactions against skin grafts and the primary and secondary proliferative graft-versus-host reactions in the popliteal lymph nodes were compared in both directions in a non-H-2 system (mouse strain combinations C57BL/10ScSnPh (further B10) and B10.C3H(40NX) further 40NX) differing at H-1 plus H-?). While 40NX recipients gave stronger reactions against B10 antigens in the allotransplantation reactions, the situation was reversed in the GVHR, B10 cells reacting more strongly against 40NX antigens. The findings of a dissociation between the mechanisms of allotransplantation reaction adn proliferative GVHR suggest that the genetic determination of the target antigens and the reacting lymphocyte populations are more complex at the minor histocompatibility systems than has been expected.

Animals↗
PubMed1977

Time dependence of the effect of splenectomy on graft-versus-host reactivity of lymph node cells.

Changes in cell-mediated reactivity of lymph node cells at various intervals after splenectomy were investigated in three assays measuring the GVH reactivity of parental cells in F1 hybrids --splenomegaly test in very young recipients and popliteal lymph node enlargement assay in adults measuring the proliferative component of the reaction, and mortality assay in sublethally irradiated recipients measuring the killer activity of the cell inoculum. During the early postsplenectomy period the reactivity of the particular amounts of lymph node cells was lower than that of cells from normal donors, but at about 3 weeks after splenectomy it was higher. The increase was of short duration in the proliferation assay and at 5 weeks the reactivity declined markedly below the control values. The increase in activity persisted for 5 weeks after splenectomy in the "killer" assay. It is probable that the described changes in cell-mediated reactivity are involved in the total effect of splenectomy on the host's complex immune response, especially against normal and tumour allografts.

Animals↗
PubMedDate not supplied

Female popliteal lymph node responses to H-Y antigen on male thymocytes in mice. II. H-2 restriction of secondary responses.

C57BL/10 (abbreviation B10) female mice give a high primary popliteal lymph node (PLN) response to syngeneic male thymocytes. The PLN response to the H-Y antigen is suppressed if B10 females are primed by an intraperitoneal injection of syngeneic male cells. Suppression of the response can be induced by priming with not only syngeneic B10 male thymocytes but also allogeneic thymocytes which share the H-2D locus of the H-2b haplotype with the responder (Db restriction). On the other hand, B10.D2, B10.A, and HTO female mice, giving a low primary PLN response to H-Y, give high secondary PLN responses when primed intraperitoneally with syngeneic male thymocytes. A high secondary response can also be obtained by priming with allogeneic male thymocytes which share the K end loci (K, A beta, A alpha, E beta, and E alpha) of the H-2 complex with the responder. Apparently the male thymocytes used for priming must share class I (and possibly class II) H-2 loci with the female recipients to enable the recognition of the H-Y antigen and subsequent development of the genetically determined type (suppression or amplification) of the secondary PLN response.

Animals↗