The opsonic properties of immune γG-globulins isolated from patients with chronic septicemic conditions, principally subacute bacterial endocarditis were studied. Opsonic capacity as well as complement-fixing properties of γ-globulins appeared to be closely associated with integrity of Fc structures. Progressive pepsin digestion of immune γG-globulins, as monitored by successive loss of Gm(a) and Gm(b) antigens, abolished opsonic activity. Colostral γA, containing agglutinating antibacterial antibodies but no demonstrable complement-fixing activity, was devoid of opsonic capacity. Reduction of γ-globulin opsonins with 0.01 or 0.1 M mercaptoethanol progressively abolished opsonic activity in parallel with loss of ability of treated γ-globulins to fix complement with bacteria. Treatment of γ-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-γ-globulin factors showing primary reactivity with Fc structures, indicate that the opsonic property of immune γ-globulins requires the participation of structures integral to the Fc region of γ-globulin.
PHAGOCYTOSIS IN SUBACUTE BACTERIAL ENDOCARDITIS : LOCALIZATION OF THE PRIMARY OPSONIC SITE TO FC FRAGMENT
- Views Icon Views
- PDF LinkPDF
- Share Icon Share
- Search Site
Paul G. Quie, Ronald P. Messner, Ralph C. Williams; PHAGOCYTOSIS IN SUBACUTE BACTERIAL ENDOCARDITIS : LOCALIZATION OF THE PRIMARY OPSONIC SITE TO FC FRAGMENT . J Exp Med 1 October 1968; 128 (4): 553–570. doi: https://doi.org/10.1084/jem.128.4.553
Download citation file: