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Biomedical subjects

A Paraf

Publications and source records attributed to A Paraf.

At least 163 records · Page 9Linked to original sources
PubMedDate not supplied

Modulation of membrane-bound enzyme activity by binding of antibodies to major histocompatibility complex antigens.

The preparation of right side-out vesicles from mouse plasmocytoma plasma membranes can be used to study the early functionnal events of the plasma membrane upon binding of ligands. Activation of two membrane-bound enzymes, 5'-nucleotidase and Na+/K+ ATPase, induced specifically by several anti-H-2 antisera was investigated. A simultaneous stimulation of these two enzymes was reported at high dilutions of antisera directed against antigens of the MHC. Comparison between the enzyme activation test and the classical cytotoxicity test showed the former being more sensitive than the latter by at least one order of magnitude. A structural coordination between some histocompatibility antigens and/or other cell surface receptors and the membrane-bound enzymes could be envisionned for the initiation of lymphocyte activation.

Adenosine Triphosphatases↗
PubMedDate not supplied

Inhibition of murine plasmocytoma tumours with antibody activity by their respective specific antigens.

Three murine plasmocytoma tumour which secrete specific antibodies have been studied for the effect of specific antigens (pneumococcal C polysaccharide and dinitrophenylated bovine gamma globulin) on the growth of these tumours in vivo. In each case, the effect of the specific antigen was to inhibit the growth of that tumour which synthesized the specific antibody. Low molecular weight haptens had no effect on tumour growth. We suggest that this antigen specific growth inhibitory effect is a function of the antigen's binding to membrane bound antibody resulting in defective membrane function.

Animals↗