Consistent with J chain expression and with the reported ability of nasal administration of L.RGG to stimulate mucosal humoral immunity [29,30,31,32], a higher presence of IgA+ cells was detected in lung parenchyma from L.RGG-treated mice (Figure 4A,E,F), even infiltrating the tumor nodules of heat-killed L.RGG-treated lung (Figure 4B,J). Here, CD79A is linked to neoplasm.