LncRNA SNHG16 Inhibits Intracellular Growth Involving Cathelicidin Pathway, Autophagy, and Effector Cytokines Production.

Long noncoding small nucleolar RNA (LncRNA) host gene 16 (SNHG16) is associated with certain diseases, including cancers. However, its role and mechanism in () infection remain unclear. Here, we demonstrated that SNHG16 expression levels were suppressed in peripheral blood mononuclear cells (PBMCs) and CD14 monocytes of tuberculosis (TB) patients. SNHG16 was up-regulated by acute infection of PBMCs from healthy control (HC) subjects. Such TB suppression of SNHG16 was consistent with an immunosuppressive-like state driven by IL-10 signaling as seen in TB patients. Notably, SNHG16 limited growth in macrophages/monocytes through autophagy and vitamin D receptor (VDR)-dependent cathelicidin (CAMP) antimicrobial pathways. Concurrently, SNHG16 was highly expressed in lymphocytes, including CD8 and Vγ2 Vδ2 T-cell subsets in HCs. SNHG16 overexpression in lymphocytes allowed them to control infection in macrophages, and SNHG16 epigenetically increased the expression of anti- effector cytokines in lymphocytes by developing more accessible chromatin states in gene loci encoding IFN-γ, TNF-α, and Granzyme B. Furthermore, the adoptive transfer of SNHG16-overexpressing human PBMCs into -infected SCID mice conferred protective immunity against infection. Thus, SNHG16 drove the induction of pleiotropic effector functions that inhibited intracellular growth in vitro and in vivo, serving as an immunotherapy target in TB.