HLA-C and infection: To further evaluate and compare antigen processing and presentation and T cell activation by CD11c+ APC populations from the BAL, lung parenchyma and the spleen, we set out to infect CD11c+ APC populations by using a recombinant adenovirus expressing OVA, a process that would involve natural infection, intracellular antigen processing and MHC pathway targeting and subsequent antigen presentation.