In respiratory and GIT infections, which is the most affected immunoglulin -
Immunoglobulin A is an antibody that plays a critical role in immune function in the mucous membranes. More IgA is produced in mucosal linings than all other types of antibody combined Ref: Ananthanarayan & Parker's textbook of microbiology 9th edition pg:97-98
IgA
IgG
IgM
IgD
Immunology