Search PubMed⌕ Search

Biomedical subjects

C P Engelfriet

Publications and source records attributed to C P Engelfriet.

At least 145 records · Page 8Linked to original sources
PubMed1977

Histocompatibility antigens and other genetic markers in ankylosing spondylitis and inflammatory bowel diseases.

Of 118 Dutch patients suffering from ankylosing spondylitis (AS) 81-4% were found to be positive for the HLA antigen B27. The B27 frequency proved to be significantly higher in patients in whom the disease had an early onset. In addition to B27, another HLA antigen may be associated with AS; the antigen Bw 16 was found to be significantly increased in B27 negative AS patients. HLA phenotype frequencies were also determined in 109 patients with idiopathic inflammatory bwel disease (IBD). In fifty-eight ulcerative colitis (UC) patients a raised incidence of A 11 was noticed. In fifty-one patients with Crohn's disease (CD) the antigen B18 showed an increased frequency. Both deviations were statistically significant. In thirty-nine patients suffering from both AS and IBD 50% proved to be B27 positive, which is significantly diffrent from B27 frequency in patients with AS alone. In the B27 negative patients with AS and IBD and increased frequency of Bw16 was also shown.

Colitis, Ulcerative↗
PubMed1977

Segregation of HLA haplotypes in 100 families with a myasthenia gravis patient.

An analysis of the HLA data of 100 myasthenia gravis (MG) patients and their first degree relatives and spouses is presented. The family studies confirmed the excess of B8 in the myasthenia gravis patients and showed that the excess was not limited to the A1, B8 haplotype. An excess of B8 homozygous patients was found from the matings of two B8 heterozygous parents, suggesting the existence of a dominant B8 linked MG susceptibility. B8 homozygous individuals run a 4-7 times higher risk of acquiring myasthenia gravis than B8 heterozygous individuals.

Female↗
PubMed1977

IgG4 autoantibodies against erythrocytes, without increased haemolysis: a case report.

A patient is described who, notwithstanding a strongly positive direct antiglobulin test with anti-IgG serum, apparently did not suffer from haemolytic anaemia. The survival of the patient's red cells, measured with 51Cr, was only slightly decreased. In vitro, the sensitized cells of the patient showed only a minimal tendency to adhere to monocytes. The patient's spleen functioned normally, since 51Cr-labelled donor erythrocytes, either sensitized with IgG-anti-D or damaged by heating, were eliminated rapidly from the circulation and sequestered in the spleen. These apparently contradictory findings could be explained by the fact that the patient's red cells were sensitized with autoantibodies, mainly belonging to the IgG4 subclass. Only weak IgG1 and IgG3 autoantibodies were detectable. Since previously the patient had suffered from a severe haemolytic anaemia, it is postulated that a switch has occurred from 'active' to 'inactive' IgG autoantibodies, perhaps induced by prednisone therapy.

Aged↗
PubMed1976

[Immunological damage to erythrocytes].

The mechanisms by which red cells are destroyed under the influence of antibodies with different immunochemical and biological characteristics are described. It is shown that the interaction of antibody with the red cell per se does not lead to a disturbance of red cell function. Activation of the whole complement system leads to direct lysis of the erythrocyte (complement hemolysis). The fixation of red cells coated with activated C3:C3 receptors on phagocytic cells is another mechanism which leads to red cell destruction. The hypothesis that adherence to the Fc-receptors of phagocytic cells is essential for the destruction of red cells under the influence of noncomplement-binding antibodies is discussed. Arguments in favour of this theory are correlation between the subclass of IgG red cell autoantibodies and the absence or presence of increased hemolysis in the patient and a correlation between the degree to which red cells of patients with this kind of antibody adhere to monocytes in vitro and the degree of hemolysis in the patient. It is shown by in vitro experiments how this adherence process can take place in vivo in the presence of normal plasma IgG although the latter completely inhibits the adherence phenomenon in vitro.

Antibodies↗
PubMed1975

Immunofluorescence microphotometry for the detection of platelet antibodies. III. Demonstration of autoantibodies against platelets.

After a survey of the literature dealing with the demonstration of platelet autoantibodies by immunofluorescence techniques, the results are given of a study in which immunofluorescence microphotometry was used for this purpose. The serum of 58, the platelets of 34, and the megakaryocytes of 2 patients with thrombocytopenia were investigated. In 21 of 52 sera (40%) in which the presence of platelet autoantibodies could be expected, positive results were obtained that could not be due to isoantibodies, either because the patients had not been pregnant and had not received blood transfusions or because the reactivity of the serum with the patient's own platelets was demonstrated. The platelets of 28 patients with thrombocytopenia not due to a platelet defect or decreased thrombopoiesis were investigated. In the platelets of 15 (54%) of these, significant differences in fluorescence were found with anti-immunoglobulin conjugate as well as with anti-IgG, -IgA, -IgM, or -complement reagents. It was concluded that in these patients in vivo sensitization of the platelets with autoantibody was demonstrated. In two patients an indication of the in vivo sensitization of the megakaryocytes was also obtained.

Antibodies, Anti-Idiotypic↗
PubMed1975

Removal of leukocytes from whole blood and erythrocyte suspensions by filtration through cotton wool. V. Results after transfusion of 1,820 units of filtered erythrocytes.

1,820 units of leukocyte- and platelet-poor erythrocyte suspensions were prepared by filtration through cotton wool. On the average more than 98% of the leukocytes and 90-95% of the platelets could be removed. The red cell recovery was 96%. 97% of the units given to polytransfused patients did not cause febrile reactions. Serological follow-up of future transplantation recipients indicated that the immunization may be avoided by using erythrocyte suspensions of fresh, filtered blood.

Antibodies↗
PubMed1975

Removal of leucocytes from whole blood and erythrocyte suspensions by filtration through cotton wool. IV. Immunization studies in rabbits.

Hetero-immunization experiments in rabbits were performed to evaluate the quantity of leucocyte antigens present in red cell suspensions prepared by the filtration method of DIEPENHORST et al., in which no intact leucocytes could be detected. It was found that the quantity of leucocyte antigens is smallest in blood filtered immediately after taking. More leucocyte-antigenic material seems to be present in blood that is filtered after storage and in frozen-thawed red cell suspensions. Evidence was obtained that granulocyte-specific antigens are more strongly immunogenic in the rabbit than lymphocyte-specific antigens or antigens common to both cells.

ABO Blood-Group System↗
PubMed1974

Myasthenia gravis, autoantibodies, and HL-A antigens.

The serum of 100 patients with myasthenia gravis and 441 of their first-degree relatives was studied for the presence of autoantibodies against several antigens. Antibodies to skeletal muscle were present in 22% of the patients and in 2% of the relatives. Both these frequencies were significantly higher than those in matched control subjects. Also, antinuclear antibodies were present more often both in the patients and in the relatives. Typing for HL-A antigens had shown a positive correlation between HL-A 8 and myasthenia gravis which was significantly higher in women than in men. Antibodies to skeletal muscle and thymomas were found to be much rarer in HL-A 8-positive patients than in HL-A 8-negative patients; HL-A 8-positive patients acquired the disease at an earlier age.HL-A 2-positive patients more often had thymomas and antibodies to skeletal muscle than HL-A 2-negative patients; HL-A 2-positive patients acquired myasthenia gravis at a later age.The fact that the clinical aspects of the HL-A 8-negative and HL-A 2-positive patients were different from those of the HL-A 8-positive and HL-A 2-negative patients justifies the hypothesis that there are two forms of myasthenia gravis.

Adrenal Glands↗