MECHANISMS FOR THE ELIMINATION OF POTENTIALLY LYTIC COMPLEMENT-FIXINGVARIABLE SURFACE GLYCOPROTEIN ANTIBODY-COMPLEXES IN TRYPANOSOMA-BRUCEI

Live antibody-coated Trypanosoma brucei parasites remove variable surf ace glycoprotein (VSG)antibody complexes from their surface upon warmi ng to 37 degrees C and evade antibody-activated complement lysis by bo th protein synthesis-dependent and protein synthesis-independent mecha nisms. The protein synthesis-dependent process follows antibody-mediat ed trypanosome agglutination, whereas the protein synthesis-independen t mechanism can occur in the absence of trypanosome agglutination. The latter process leads to a more rapid elimination of complement-fixing VSG-antibody complexes.