Scheme 1.
Hsp70 binds to TREM-1 on monocytes and induces mRNA expression of TNFα and IFNγ. Signal transduction recruits CD3+CD4+ lymphocytes and leads to appearance of IL-2 in conditioned medium, which promotes the maturation of cytotoxic lymphocytes CD3+CD4+, CD16+CD56+, and CD3+CD8+. At the same time, Hsp70 directly binds to NK cells and promotes their transition to cytotoxic cells.