However, ATB/HIV+ individuals did exhibit significantly reduced IgG2, IgG4, IgA1, IgA2, and IgM titers to tetanus toxoid (Fig. S1 and S2), as well as reduced IgG1, IgG2, and IgM titers to influenza HA compared with ATB/HIV− individuals (Fig. S1 and S2). This evidence concerns the gene IGHA1 and influenza.