THE HUMAN IMMUNE SYSTEM
BLOOD GROUPS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Antibodies are most often immune
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Associated with HTR
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Shows reactive dosage between homozygous vs heterozygous cells
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Strongly fixes complement
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Detailed explanation-1: -Although IgA coated directly on plastic surfaces activated the alternative complement pathway in a dose-dependent manner, IgA antibodies bound to antigen failed to fix complement by either classical or alternative pathways.
Detailed explanation-2: -If this antigen is cell-localized, then the deposition of complement elements will cause cell lysis. CFix to IgM is stronger (> 1000 times/antibody molecule) than that to IgG. CFix antibodies can be raised against some or all viral proteins.
Detailed explanation-3: -Serum IgM exists as a pentamer in mammals and comprises approximately 10% of normal human serum Ig content. It predominates in primary immune responses to most antigens and is the most efficient complement-fixing immunoglobulin.
Detailed explanation-4: -However, the complement fixed by IgG antibody was shown to be highly lytic both for sheep red cells and dog kidney tissue culture cells. The fixation of complement by IgM antibodies resulted in weak and relatively ineffective cytolysis of dog kidney cells, but effective haemolysis of sheep red cells.