Biomedical subjects
Publications and source records attributed to H Matej.
Data on the antigen non-specific and antigen specific genetic control of immune response are presented. Particular emphasis is placed on the role of the major histocompatibility complex in the regulation of immune functions.
Lymphocytes of 6 patients with infectious mononucleosis were found to be capable of responding in mixed lymphocyte culture (MLC) to Epstein-Barr virus (EBV)--transformed lymphoblastoid cell lines and Raji cells, whereas their response to PWM-induced blasts and non-T cells was significantly depressed. This means that despite the suppression of cellular reactivity, observed in infectious mononucleosis, the specific response to EBV-infected cells remains unaffected.
The MLC response of normal lymphocytes to different kinds of EBV-transformed LCL was investigated. The response to allogeneic LCL cells remarkably exceeded the response to xenogeneic and autologous LCL cells. Stimulation performed with EBV-transformed and normal cells obtained from the same donors showed a correlation in the reaction levels (Q = 0.434). This incomplete correlation was not improved by the reduction of the number of stimulating LCL cells. In MLC stimulated with LCL no statistically significant differences between responses to 2,1 or alloantigens were found.
A segregation procedure of human lymphocytes by successive rosetting with mouse and sheep red blood cells, and separation of rosettes by Ficoll Hypaque gradient centrifugation, is described. This method yields four lymphocyte subpopulations: lymphocytes with mouse and sheep receptors (M+E+), with mouse receptor only (M+E-), with sheep receptor only (M-E+), and without any receptors (M-E-). Presence of surface membrane receptors: E, C3, Fc, and DR on the cells in the subpopulations have indicated that M-E+ and M+E+ cells are T cells, M+E- cells are B cells and M-E- cells are nonhomogeneous, consisting of B cells, T cells, monocytes, and granulocytes.
In fifty-four healthy individuals aged from 22 to 53 the response of lymphocytes to PHA stimulation and to stimulation with allogeneic lymphocytes were determined. A linear age-related decrease in reactivity to PHA (r = 0.500, P less than 0.01), as well as to allogeneic stimulation (r = 0.351, P less than 0.01) was found. The correlation between these two parameters of T lymphocyte function was weak (r = 0.207, not significant).
A technique for obtaining highly enriched B lymphocyte subpopulation from isolated peripheral blood lymphocytes is described. The method consists in combined use of mouse and sheep red cell rosettes. In the first step of the method, B cells-containing fraction of lymphocytes and papainized mouse red cells form rosettes which are separated by Ficoll-Hypaque gradient centrifugation. In the second step, after lysis of mouse erythrocytes in the sediment, the recovered B cell rich fraction is purified by E rosetting procedure, B lymphocyte subpopulation obtained in this way, presents a good viability and is almost completely pure.
Allogeneic bone marrow or spleen cells were transplanted in rabbits treated with a single dose of 110 kmg/g of cyclophosphamide or four doses of 50 mg/kg. Chimerism of peripheral blood cells occurred in about 50% of the recipients, lasting from about the 14th day until 180 days after transplantation. The chimerism was limited to some kinds of cells since dissociation of proliferation of hemopoietic cells and split chimerism of lymphocytes were observed. Dissociation of proliferation of hemopoietic cells consisted in the appearance of only one cell line, namely lymphocytes, whereas the erythrocyte cells did not proliferate. Split chimerism occurred within lymphocytes, manifested by the presence of the donor's T lymphocytes but absence of proliferation of the donor's B lymphocytes.
B lymphocyte subpopulations taken from 89 individuals were investigated with 180 sera from the seventh Histocompatibility Workshop. The results obtained served in determining the frequency of 8 DRw antigens in a tested population sample. Their incidence was comparable to the frequencies determined during the Workshop for the reference group of European Caucasoids.
The incidence of antinuclear antibodies (ANA) in asbestos textile workers was compared with the results of HLA typing. HLA B8 antigen was more frequent in the ANA-positive group as compared to the ANA-negative group. The relative risk of this associati-n is 2.77 (p less than 0.02) without correction for the number antigens tested. A decrease in frequency of HLA A10 in workers with ANA was also found. The results suggest that the development of ANA under asbestos hazard may depend on inherited predisposition of which HLA B8 is a marker.
Allogenic transplantations of bone marrow or spleen cells were carried out on rabbits treated with cyclophosphamide. About 50% of the recipients developed chimerism of peripheral blood cells. Chimerism was a passing phenomenon prevailing from 14 to 180 days after grafting. A phenomenon indicating that not all cell lines develop after transplantation from the donor stem cells, was observed. This phenomenon has been called "restricted chimerism". The GvH reaction was of a chronic type. Relative spleen weights were significantly increased in animals receiving the spleen cell grafts, but not in animals receiving bone marrow grafts. A direct positive erythrocyte Coombs test was found in almost all graft recipients. In addition cytotoxic autoantibodies against lymphocytes were present in sera of about 20% of the recipients.
Efficiency of three different methods: Bernstein's, maximum likelihood and determinant method were compared. A relative efficiency calculated as a ratio of variances of estimators was used for the comparison. It was shown that the determinant method is almost as efficient for estimating of recessive gene frequency as the method of maximum likelihood, and more efficient than the Bernstein's method.
The investigation was carried out with HeLa cells which were not sensitive to antiviral action of human diploid cell interferon and do not produce interferon after induction with Newcastle disease virus. Identity of this line was confirmed by determination of stable genetic markers such as isoenzymes and histocompatibility antigens. On electrophoresis of lysed HeLa cells the following human red cell enzymes phenotypes were found: PGM (1-1), AP, EsD, and GTP. It was shown that on the surface of HeLa cells membranes HLA antigens are expressed: A28, BW35, A3. The results are in agreement with those which were obtained from Henrietta Lack's family study. Chromosome G-banding analysis revealed disproportion between the number of chromosomes connected with production and action of interferon and chromosomes which are supposed to control these processes.
One hundred thirty-four workers in an asbestos factory who had been in contact with asbestos for about 20 years, were typed for 22 HLA antigens of the A and B loci. In this group, 22 workers were diagnosed as asbestosis patients on the basis of chest radiography and clinical findings; the remaining 112 were without signs of asbestosis. In the group of asbestosis patients an increase of B27 antigen was observed in comparison with the group without asbestosis (27-27% and 9-82% respectively). The relative risk = 3-44 is significant at the level of p less than 0-05. These results may indicate that a genetic factor, connected with HLA locus has influence on the development of asbestosis under conditions of contact with asbestos.
One hundred twenty-five patients with rheumatoid arthritis were typed for 21 HLA antigens from A and B loci. The antigen frequencies found in patients were compared with the frequencies in a control population of 300 healthy individuals. No statistically significant differences were observed between patients and the control group.
The appearance, distribution in serum fractions, and specificity of cytophilic and cytotoxic antibodies in rabbits after skin allotransplantation were investigated. The sera were obtained from rabbits receiving three subsequent skin allografts across the RL-A barrier. The direct cytophilic test and the microcytotoxic test using the graft recipients sera and lymphocytes from the donor rabbits, as well as lymphocytes from other rabbits were performed. In all the sera under investigation both cytophilic and cytotoxic antibodies were found. The specificity of cytotoxic antibodies was directed against rabbit histocompatibility antigens (RL-A), in contrary to cytophilic antibodies, which were strongly active with the donor lymphocytes, and to a somewhat lesser degree with other lymphocytes, regardless their RL-A constitution. Posttransplantation cytophilic and cytotoxic antibodies were present in the gamma1 and gamma2 classes of immunoglobulins and absent from the IgM immunoglobulins. It is concluded, that allografted rabbits develop, besides the known cytotoxic antibodies, also cytophilic antibodies, not connected with the strong histocompatibility antigen system.
A panel of 150 Rh+ and Rh-- donors was tested by the NIH-microcytotoxicity test against 90 antisera determing 21 HL-A antigens. For platelet and leukocyte transfusions, donors compatible in ABO and Rh groups as well as in HL-A antigens, were used. In some cases the donor and recipient were compatible in three HL-A antigens, in other cases the degree of compatibility was less satisfactory. Platelet and leukocyte concentrates were prepared by double thrombo- and leukocyte-pheresis. Before transfusions the cross cytotoxicity test with donor's lymphocytes was performed. No transfusion accidents occurred; in some patients a beneficial effect was noticed.
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