Serum matters: human platelet lysate enables physiological modeling of HIV-1 infection in dendritic cells

Monocyte-derived Dendritic Cells (moDC) are fundamentally involved in infectious processes and serve as model cell type for studying immune regulatory functions in vitro . How DCs behave in viral infections is influenced by various intra- and extracellular factors. Thus, working as physiologically as possible is crucially important for gaining mechanistic insights. We and others previously stressed a critical role of DCs in the course and transmission of human immunodeficiency virus (HIV) infection. Up to date, moDCs are differentiated in presence of FCS-based media, comprising undefined factors that might impact cell differentiation behavior and function. While a few studies addressed working under xeno-free conditions enhancing reproducibility and clinical applicability, differences between FCS and hPL-generated DCs with respect to infection disease processes remain poorly defined. In this study we established an animal component-free protocol to induce primary moDCs, and systematically compared FCS stimulated DCs versus hPL-induced DCs phenotypically and functionally. Our data revealed, that hPL shows high differentiation potential and infection potency of DCs by complement-opsonized HIV-1 (HIV-C). All in all, we established an animal component-free in vitro model to generate primary CD11c + CD209 + -moDCs by use of hPL, which is a valuable tool to study viral infections and interactions in vitro and under more defined conditions compared to FCS-generated DCs.