Functional analysis of HPV-like particle-activated Langerhans cells in vitro.

Langerhans cells (LCs) are antigen-presenting cells responsible for initiating an immune response against human papillomaviruses (HPVs) entering the epithelial layer in vivo as they are the first immune cell that HPV comes into contact with. LCs become activated in response to foreign antigens, which causes internal signaling resulting in the increased expression of co-stimulatory molecules and the secretion of inflammatory cytokines. Functionally activated LCs are then capable of migrating to the lymph nodes where they interact with antigen-specific T cells and initiate an adaptive T-cell response in vivo. However, HPV has evolved in a manner that suppresses LC function, and thus the induction of antigen-specific T cells is hindered. While many methods exist to monitor the activity of LCs in vitro, the migration and induction of cytotoxic T cells is ultimately indicative of a functional immune response. Here, methods in analyzing functional migration and induction of antigen-specific T cells after stimulation of LCs with HPV virus-like particles in vitro are described.