However, a study with children from the United States showed that greater IgA titers (>200) correlated with protection from natural infection.70 As for the mechanism of protection, it has been hypothesized that the serum and/or sIgA may neutralize rotavirus.71 However, work using IgA mAbs directed against the intermediate capsid protein VP6 of rotavirus in mice did not neutralize the virus, but inhibition of viral transcription in epithelial cells was observed.4 The role of serum IgA Fc functions in rotavirus protection and clearance is yet to be reported. The gene discussed is CD79A; the disease is infection.