HELP! CAN SOMEBODY TRANSLATE THIS IN SPANISH? Increased IgG1–IgG4 and decreased IgA1 levels were found in CHC patients . Changes in salivary IgA1 ⁄ IgA2 concentration ratio could result from the preferential stimulation of antibody production by IgA1- or IgA2-synthesizing plasma cells by antigen in the oral cavity . It is also well known that salivary IgA1 can be cleaved by a variety of enzymes from oral microorganisms. Furthermore, IgA subclass ratio may be changed during the active immune response, reflecting the generation of specific antibodies to various antigens of mucosal pathogens, so that decreased salivary IgA1 seen in our CHC patients may indicate the failure of protective effect of IgA1 antibodies in these patients.