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Biomedical subjects

R Matre

Publications and source records attributed to R Matre.

198 records · Page 11Linked to original sources
PubMed1978

Traffic of T and B lymphocytes in the normal spleen.

The occurrence of C3b and C3d complement receptors and of Fc and E receptors in normal splenic tissue was studied in cryostat sections incubated with specific marker cells. Thereby the topographic distribution of T and B lymphocytes in the splenic tissue was mapped: Te lymphocytes are found especially in the periateriolar sheaths, B lymphocytes in eccentric zones around the arterioles. The cells in the splenic pulp carry especially Fc, but also C3b receptors, whereas C3d receptors appear to be specific of lymphocytes. The basic lymphocyte traffic behind the mapped distribution of the lymphocyte subpopulations in the spleen was elucidated by lymphocyte kinetic studies using autologous 51Cr-labelled reinfused lymphocytes. These studies were performed partly on normal persons and partly on splenectomized persons without immune defects. The results indicate the presence of an exchangeable pool of T as well as of B lymphocytes in the spleen, the T cell pool being larger and making up in normals about 30% of the total exchangeable T lymphocyte mass. The matrix for the T lymphocyte pool in the spleen is the periateriolar sheaths. The difference in structure between the lymph nodes and the lymphoid tissue of the spleen, including differences in the distribution of lymphocyte subpopulations, are explained by the special vascular arrangement in the spleen.

Adult↗
PubMed1978

Acute hemolytic anemia related to diphtheria-pertussis-tetanus vaccination.

Three infants developed severe hemolytic anemia following the second or third diphtheria-pertussistetanus vaccination. Direct antiglobulin tests were positive, and the infant most severely affected also had reduced serum complement levels, indicating an immunological mechanism for the hemolysis. The presence of IgM on the erythrocytes from 2 of the infants could be demonstrated by antiglobulin tests or immunization experiments. Heat eluates of the erythrocytes from one of the infants contained antibodies to tetanus and diphtheria toxoids, as well as to Bordetella pertussis, suggesting that these antibodies were antigenically bound to the erythrocytes. Virus antibodies or isoagglutinins, present in the serum, were not found in the eluate. No antibodies against the vaccine components could be demonstrated in eluates of erythrocytes from control subjects. In vivo experiments showed that tetanus and diphtheria toxoids were easily bound to human erythrocytes. This finding could help explain the pathogenesis of the autohemolysis.

Acute Disease↗
PubMed1978

Fcgamma receptors in human choroid plexus.

Crysotat sections of human choroid plexus adsorbed erythrocytes sensitized with IgG antibodies of human and rabbit origin. No adsorption occurred when the erythrocytes were sensitized with F(ab')2 or Facb fragments. The reaction was strongly inhibited by intact IgG and by Fc fragments and not inhibited by Facb and F(ab')2 or albumin. These properties are similar to those of corresponding receptors in human placenta. The presence of an Fcgamma receptor in choroid plexus may be of significance for the transfer of IgG from blood to cerebrospinal fluid.

Choroid Plexus↗
PubMed1977

Similarities of Fcgamma receptors on trophoblasts and placental endothelial cells.

The trophoblastic tissue and endothelium of fetal stem vessels in cryostat sections of first-trimester and term human placentae adsorbed erythrocytes sensitized with IgG antibodies of human, rabbit, and guinea pig origin. Native and heat-aggregated human and rabbit IgG, and human IgG subclasses except IgG2 inhibited the hemadsorption. However, the Fc fragment of IgG2 inhibited the hemadsorption similarly to the Fc of pooled IgG. No inhibition was obtained with other immunoglobulin classes or fragments. The inhibitory activity of IgG and Fc fragments was abolished by partial reduction and alkylation, indicating that inter-heavy-chain disulfide bonds are required for the binding. Immune complexes prepared at slight antigen excess showed an eightfold stronger inhibition than antiserum alone. Both receptors were sensitive to formaldehyde, periodic acid, and heat. The Fcgamma receptors on the trophoblasts and on the endothelium in human placentae are apparently similar.

Animals↗
PubMed1977

Multiple FC receptors in the human placenta.

The presence of Fc receptors on endothelium and trophoblastic tissue in cryostat sections of full-term human placentae has been verified. Fc receptor activity on stem vessel endothelium can be manifest both by immunofluoresence with heat-aggregated IgG and by haemadsorption with antibody-sensitized erythrocytes. However, Fc receptor activity on trophoblastic tissue is manifest only in the haemadsorption reaction, and not in the immunofluorescence reaction. The haemadsorption and immunofluorescence were both independent of temperature, and were completely abolished by formaldehyde fixation of the tissue sections. Both reactions were expressed on first-trimester placental tissue, although more limited and diffuse. In terms of their anatomical location and specificity characteristics the Fc receptors in human placentae may have a biological significance.

Endothelium↗
PubMed1977

Surface markers in non-phagocytic hairy cell leukemia.

By phase contrast and scanning electron microscopy hairy cells were demonstrated in the peripheral blood, bone marrow and spleen of a patient with hairy cell leukemia. Immunofluorescent tests revealed IgD on the surface of 92 per cent, IgG, on 76 per cent, IgM on 12 per cent and albumin on 95 per cent of the cells from the spleen. After overnight culture, IgG and albumin were detected on 4 and 6 per cent of the cells respectively, while the number of IgD and IgM positive cells persisted. Fifty-two per cent of the hairy cells formed rosettes with erythrocytes sensitized with IgG antibodies (EA), whereas 70 per cent formed rosettes after trypsin and protease treatment. The hairy cells did not form rosettes with erythrocytes sensitized with IgM antibodies and complement (EAC), or with sheep and mouse erythrocytes. Cryostat sections of spleen strongly adsorbed EA, whereas no adsorption occurred with EAC or sheep erythrocytes. The hairy cells did not phagocytize latex particles or ingest a strain on yellow staphylococci. The results suggest that hairy cells from this patient probably were of B-lymphocyte origin.

Bone Marrow↗
PubMed1977

A human IgA myeloma protein interacting with staphylococcal alpha-toxin and protein A.

High anti-staphylolysin activity was found in the serum from a patient with multiple myeloma. The activity was confined to the monoclonal IgA protein and was dependent on an intact Fc part of the molecule. An Fc-dependent interaction with protein A was also demonstrated. In addition, a part of the monoclonal IgA was found to be complexed with alpha2-macroglobulin. The results imply an unusual Fc-reactivity of the IgA protein.

Adult↗
PubMed1976

Properties of Fcgamma receptors in normal and malignant human tissues.

Properties of the IgG receptors were studied by treating tissue sections or suspensions of peripheral mononuclear cells with various chemical reagents and determining changes in their ability to react with IgG-sensitized erythrocytes (EA). A heterogeneity of the Fc receptors was revealed. Iodoacetamide, 2-mercaptoethanol, sodium azide, EDTA, and a pH varying from 6.0 to 8.2 had no effect on Fc receptors in sections of normal lymphoreticular tissue and malignant tissue. Formaldehyde, low pH, and high salt concentrations affected receptor activity to various degrees. Receptors in liver sections and on monocytes were generally more resistant than receptors in spleen sections and on B lymphocytes. Receptors in malignant tissue behaved either like receptors in spleen or like receptors in liver. Although all tissues were sensitive to periodic acid, the Fc receptors in malignant tissue were always more resistant.

Azides↗
PubMed1976

Complement receptors in human renal glomeruli.

Glomeruli in Cryostat sections of foetal and adult renal tissues adsorbed sheep erythrocytes sensitized with IgM antibody and human or mouse complement (EAC). Activated complement was essential for the reaction to occur. The receptor had specificity for the C3b fragment of C3 and is probably of protein or glycoprotein nature. Complement receptors in glomeruli may explain the deposition of complement components or complement-containing complexes in immune-complex glomerulonephritis.

Animals↗
PubMed1976

Specificity of Fcgamma receptors in human malignant tissue and normal lymphoreticular tissue.

The specificity of the Fcgamma receptors in normal spleen and liver and in malignant tissues was studied using hemadsorption to cryostat sections. Indicator cells (EA) were sheep erythrocytes (E) sensitized with rabbit IgG antibody (A). The binding of EA to sections of normal and malignant tissues was inhibited by pooled IgG of human, rabbit, and guinea pig origin and by human IgG1, and IgG3, and IgG4 myeloma proteins. Heat-aggregated IgG inhibited the binding to sections of liver and some malignant tissues more effectively than monomeric IgG. The Fc fragments of IgG were also inhibitory, but not the F(ab')2, Fab', and Facb fragments. The inhibition obtained increased with decreasing amounts of A used for sensitization of E. The inhibitory activity of IgG was abolished after partial reduction and alkylation. No inhibition was obtained with IgG2, IgM, IgA, or albumin. E sensitized with Facb or F(ab')2 fragments of A did not bind to normal or malignant tissues. The specificity of the Fc receptors in normal spleen and liver and in malignant tissues is apparently very similar.

Antibody Specificity↗
PubMed1975

Fc receptors in human placenta.

Cryostat sections of placental tissue strongly adsorbed erythrocytes sensitized with IgG antibodies of human, rabbit, and guinea pig origin. No adsorption occurred using erythrocytes sensitized with F(ab')2 fragments. The reaction was strongly inhibited by intact IgG and by Fc fragments, weakly inhibited by pFc' fragments, and not inhibited by Facb and F(ab')2 or albumin. These properties are similar to those of corresponding receptors in normal lymphoid tissues. Results obtained with sections of hydatidiform mole showed that the reaction occurred with the trophoblastic tissue. Porcine placenta had no Fc receptor activity. The presence of an Fc receptor in human placental tissue may therefore be of significance for the selective transfer of IgG from mother to foetus.

Animals↗
PubMed1975

Specificity of human serum antibodies against endotoxin from N. gonorrhoeae.

Sera from patients with gonorrhoea were used to study the specificity of human antibodies against determinant a of endotoxin from gonococcal strains 8551, V, and VII. The sera were tested by an indirect haemagglutination technique before and after absorption with endotoxin from the same strains. The sera were used untreated and treated with mercaptoethanol (ME). The untreated and ME-treated sera showed antibody activity against all the a determinants when examined unabsorbed. After absorption with any of the endotoxin preparations the sera usually demonstrated antibody activity against one or both of the other preparations. The pattern of reactivity thus observed differed from one serum to another. Treatment of sera with ME resulted in an altered pattern of reactivity of four of the five sera. The results indicate multispecificity of human antibodies against the a determinants.

Animals↗
PubMedDate not supplied

In-situ characterization of mononuclear cell infiltrates in lesions of multiple sclerosis.

The mononuclear cell infiltrates in autopsy material from brains and spinal cords of six patients with multiple sclerosis (MS) were characterized in situ. Receptors for sheep erythrocytes and anti-T lymphocyte serum were used to identify T lymphocytes. Receptors for the activated third components of complement and for the Fc-portion of IgG (Fc gamma receptors) were used as markers for macrophages and lymphocytes. In acute and recent MS lesions, perivascular infiltrates of mononuclear cells were commonly found. Most cells were T lymphocytes. Some B lymphocytes were also demonstrated. The demyelinating lesions contained large numbers of lipid macrophages expressing Fc gamma receptors. The lipid macrophages are probably derived from microglial cells. The chronic, demyelinated lesions contain a few mononuclear cells, mainly B lymphocytes and plasma cells.

Adult↗