Antibody (Ab)-dependent and-independent activation of the duck complement (C') system were studied. Ab-independent C' activity exhibited characteristics similar to those of the mammalian alternative C' pathway (ACP), including the selective lysis of rabbit erythrocytes (RRBC), a requirement for Mg2+, but not Ca2+, depletion of activity by zymosan, and lack of sensitivity to the mammalian C1 inhibitor carrageenan. Measurement of C' activity using antisera against sheep erythrocytes (SRBC) revealed that duck Abs activate C' by a pathway resembling the mammalian classical pathway (CCP) requiring both Ca2+ and Mg2+.
View Article and Find Full Text PDFThe activation requirements and pathways of the serum C' system of the marsupial Monodelphis domestica were characterized using standard hemolytic procedures. The existence of distinct classical and alternative activation pathways was established on the basis of their ionic requirements, hemolytic capacity at different temperatures, kinetics of hemolysis, and differential susceptibility to the classical pathway inhibitor carrageenan. For the most part, the activities of these pathways were influenced by factors and conditions in a manner similar to the way they affect the activity of eutherian complement.
View Article and Find Full Text PDFClinical and animal studies suggest that burn injury induces alterations in zinc metabolism. It also has been established that zinc nutriture can cause alterations in the immune response, but there is a paucity of information concerning the interrelationship between burn injury, zinc nutriture and the immune response. In the present study, rats were subjected to full skin thickness dorsal scald injuries covering 30 per cent of the total body surface and then maintained on sufficient or deficient zinc intake.
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