Other promising non-human trials have demonstrated that vaccines may improve gastrointestinal tract immunity by recruiting IgA secreting plasma cells to the mucosa or decreasing the local HIV burden [38, 39], and the use of a bovine serum immunoglobulin in adults with HIV enteropathy improved duodenal absorptive function and increased mucosal CD4+ T cell density [40]. Here, CD4 is linked to HIV enteropathy.