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K Miklós

Publications and source records attributed to K Miklós.

12 recordsLinked to original sources
PubMed1992

Antibody mediated lysis of hapten-conjugated target cells by macrophages and by complement: the influence of IgG subclass, antibody and hapten density.

Lysis of 51Cr-labeled TNP-SRBC sensitised by rat IgG1 or IgG2a type antibodies by homologous, paraffin oil-elicited peritoneal macrophages (ADCC) or by homologous complement was studied. IgG2a was found to be markedly more efficient in mediating both ADCC and complement dependent lysis compared to IgG1. Inhibition of the ADCC pointed to the involvement of separate but partially overlapping interaction sites for the two isotypes. We suggest that FcRII type receptors play a favoured role in both IgG2a and IgG1 mediated ADCC. The threshold amount of bound antibody required for ADCC was lower than that sufficient for complement dependent lysis regardless on the subclass or on hapten density. The extent of lysis (both ways) was found to depend on hapten density using equal amounts of antibody. The results are interpreted as terms of the possible requirements for association of IgG molecules on the target cell surface.

Animals↗
PubMed1992

Interaction between rat peritoneal macrophages and sensitised erythrocytes: dependence on IgG subclass, antibody density and the degree of hapten conjugation.

The interaction between macrophages (M phi) and antibody sensitised target cells was studied by the use of rat peritoneal macrophages, TNP hapten conjugated sheep red blood cells (SRBC) and homologous antibodies of subclasses IgG1 and IgG2a. Under optimal conditions, the great majority of the M phi formed rosettes with IgG1-sensitised antibodies while a maximum of 50% was achieved when target cells were sensitised by IgG2a. Using a double rosette technique, the major part of rosette-forming cells was found to bind both of the isotypes. IgG1-mediated rosette formation was observed at very low degrees of sensitisation as opposed to IgG2a-mediated target cell binding. Not only the amount of bound antibody but also the degree of hapten conjugation (epitope density) appear to influence the ratio of rosette-forming cells. IgG1-mediated rosette formation was partially inhibited by monomeric IgG1 and more efficiently by soluble ovalbumin (OVA)-anti-OVA complexes involving IgG1-type antibodies, while IgG2a mediated rosette formation was inhibited by OVA-anti-OVA complexes containing IgG2a type antibodies, and less efficiently by complexes involving IgG1. No inhibition was found by monomeric IgG2a. Based on the present data, we propose that two types of receptors are involved in the interaction of M phi and target cells coated by IgG1 and/or IgG2a type antibodies. One requires a multiple antibody-receptor interaction, binding both subclasses at overlapping binding sites; the other is able to interact with IgG1 and does not depend on the multiplicity of interactions.

Animals↗
PubMed1979

Studies of pre- and postimmunization antibodies of sheep.

Serum samples were taken serially from three nonimmunized sheep over a long period of time. Antibodies to human serum albumin (HSA), ovalbumin (OA) and FITC were separated from the samples. Than, two of the animals were injected with HSA+ complete Freund's adjuvant, the third with adjuvant without antigen. Serial postimmunization serum samples were subjected to the same procedures as the pre-immunization ones. The specific antibodies increased in concentration, and only the postimmunization antibody population was able to precipitate. In the presence of the antigen, the postimmunization antibodies bound to the Fc receptors of lymphocytes to an increased degree. There was no difference between pre- and postimmunizaton antibody populations either in complement-activating capacity or in the quantity of antigen necessary for reaching antigen-antibody equivalence. Isoelectro-focusing showed no new bands which would indicate antibodies different from the pre-existing ones. However, changes were observed in the relative participation of the antibodies forming different bands. No sharp limit was observed between pre- and postimmunization antibody populations. The Ig increment demonstrated after immunization was accompanied by a similar increment in the specific antibodies tested in the animal that had not given antigen, but not in the others. The authors attribute a role to humoral antibodies already in the earliest phase of immune response.

Animals↗
PubMed1976

[Modification of the Romeis method for cartilage staining].

When staining of the cartilage by the method of Romeis one can increase of the electivity using more acidic staining solution for a shorter period. For fixation instead of solution of ammoniummolibdate, solution of phosphotungstic acid is recommended.

Animals↗
PubMed1976

[Demonstration of bone lacunes and canicules].

Schmorl's thionin-dye was applied to paraffin embedded sections after decalcination in a ferrichlorid-hydrochlorid acid solution. Using this modification long-lasting treatment with Müller's solution or celloidin embedding can be avoided.

Bone and Bones↗
PubMed1975

[Glia staining].

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Neuroglia↗