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Biomedical subjects

R C Williams

Publications and source records attributed to R C Williams.

At least 613 records · Page 34Linked to original sources

Phagocytosis in subacute bacterial endocarditis. Localization of the primary opsonic site to Fc fragment.

The opsonic properties of immune gammaG-globulins isolated from patients with chronic septicemic conditions, principally subacute bacterial endocarditis were studied. Opsonic capacity as well as complement-fixing properties of gamma-globulins appeared to be closely associated with integrity of Fc structures. Progressive pepsin digestion of immune gammaG-globulins, as monitored by successive loss of Gm(a) and Gm(b) antigens, abolished opsonic activity. Colostral gammaA, containing agglutinating antibacterial antibodies but no demonstrable complement-fixing activity, was devoid of opsonic capacity. Reduction of gamma-globulin opsonins with 0.01 or 0.1 M mercaptoethanol progressively abolished opsonic activity in parallel with loss of ability of treated gamma-globulins to fix complement with bacteria. Treatment of gamma-globulin opsonins with 0.01 M sodium metaperiodate also produced complete loss of opsonic capacity in parallel with loss of Gm(b) Fc antigens. These findings, together with antiopsonic effects demonstrable with anti-gamma-globulin factors showing primary reactivity with Fc structures, indicate that the opsonic property of immune gamma-globulins requires the participation of structures integral to the Fc region of gamma-globulin.

Agglutination Tests↗

Serum opsonin, bacteria, and polymorphonuclear leukocyte interactions in subacute bacterial endocarditis. Anti-gamma-globulin factors and their interaction with specific opsonins.

The effect of anti-gamma-globulin factors on 7S gamma-globulin opsonins from patients with subacute bacterial endocarditis has been examined with a quantitative in vitro phagocytosis system. Human anti-gamma-globulin factors from patients with subacute bacterial endocarditis and rheumatoid arthritis inhibited the opsonic action of 7S gamma-globulin specifically bound to bacteria. A similar antiopsonic effect was obtained with rabbit antiserum to human gammaG globulin. The antiopsonic effect of anti-gamma-globulin factors did not correlate with their ability to potentiate agglutination of bacteria by 7S antibody. Competition was demonstrated between the antiopsonic effect of anti-gamma-globulin factors and the phagocytosis-promoting action of heat-labile serum factors containing hemolytically active complement.

Agglutination Tests↗