IFNA1 and HIV-1 infection: Models of Simian Immunodeficiency Virus (SIV), a retrovirus closely related to HIV-1, demonstrate that pDCs traffic from the circulation, where they are depleted, to the GALT, where their overabundance contributes to inflammation through the release of cytokines.11, 12, 13 In the acute stages of HIV-1 infection, pDCs produce type 1 interferons (IFN-Is) as one of the first lines of defense against the virus,14 and are therefore protective.