HIV-1 p17 matrix protein enhances type I interferon responses through the p17-OLA1-STING axis.

Stimulator of IFN genes (STING; also known as STING1) is an important adaptor protein for detecting cytosolic double-stranded DNA, which can come from HIV infection. Several HIV proteins, such as p6, Vpx and Vif, can influence STING-mediated innate immunity, but the function of p17 is still unknown. In this study, we find that HIV-1 p17, but not HIV-2 p17 or SIV p17, promotes STING signaling induced by cyclic GMP-AMP (cGAMP) treatment.

Newly synthesized AIFM1 determines the hypersensitivity of T lymphocytes to STING activation-induced cell apoptosis.

STING is a well-known signaling adaptor essential for sensing cytosolic dsDNA to produce type I interferon. Although the detailed underlying mechanisms remain enigmatic, recent studies show that STING activation can lead to T lymphocyte apoptosis. Here, we report that AIFM1 facilitates STING activation-induced cell apoptosis in T lymphocytes.

Protocol using lentivirus to establish THP-1 suspension cell lines for immunostaining and confocal microscopy.

THP-1, a monocyte cell line growing in suspension, is widely used in immunology research. However, establishing suspension cell lines and performing confocal microscopy can be challenging. Here, we present a protocol to efficiently generate THP-1 cell lines using lentivirus and perform immunostaining and confocal microscopy.

ALG2 regulates type I interferon responses by inhibiting STING trafficking.

Stimulator of IFN genes (STING), an endoplasmic reticulum (ER) signaling adaptor, is essential for the type I interferon response to cytosolic double-stranded DNA. Translocation from the ER to perinuclear vesicles following cyclic GMP-AMP (cGAMP) binding is a critical step for STING to activate downstream signaling molecules, which leads to the production of interferon and pro-inflammatory cytokines. Here, we found that apoptosis-linked gene 2 (ALG2, also known as PDCD6) suppressed STING signaling induced by herpes simplex virus-1 (HSV-1) infection or cGAMP presence.

ALG2 Influences T cell apoptosis by regulating FASLG intracellular transportation.

In the immune system, T lymphocytes undergo rapid clonal expansion upon pathogen infection. Following pathogen clearance, most of proliferated T cells will be eliminated by the apoptosis pathway to keep the balance of immune cells. FASLG, by interacting with its cognate receptor FAS, plays a major role in controlling the T cell death.