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What is A child is suffering from recurrent chronic infections with encapsulated bacteria; Which subclass of IgG does the child has deficiency and explain in detail?
* IgG has four subclasses: IgG1, IgG2, IgG3 and IgG4 * IgG2 antibody is directed against polysaccharide antigens and hence it is most impoant defence against encapsulated bacteria. Ref:- Review of medical microbiology and immunology 13th ed; pg num:- 1127