Culturally Targeted Video Intervention to Increase PrEP Use Intentions Among Latinx Sexual Minority Men: A Pilot Randomized Controlled Trial.

Background: Latinx sexual minority men experience the greatest second highest human immunodeficiency virus (HIV) burden in the United States. Pre-exposure prophylaxis (PrEP) is the most effective HIV prevention tool available, however, PrEP uptake remains low among this group. Methods: This two-arm pilot randomized controlled trial study aimed to assess the feasibility and preliminary efficacy of delivering an online culturally targeted video intervention that aims to increase PrEP uptake intentions among Latinx sexual minority men. The intervention group received a culturally targeted video that contained the same PrEP information as the control group and incorporated positive aspects of Latinx masculinity (i.e., caballerismo). Participants were recruited through Amazon's MTurk crowd-sourcing platform. A total of twenty-five participants met the study inclusion criteria (N = 25). Results: The control group had a higher mean PrEP intentions score (M: 3.3, 95% CI: 2.7-3.9) when compared with the intervention group. A moderate, negative, linear correlation was observed between machismo and PrEP intention scores (r = -.34). In contrast, a small, positive correlation was found between caballerismo and PrEP intentions (r = .19). Conclusions: While the culturally targeted video intervention did not increase PrEP use intentions, the study highlights the importance of understanding and addressing cultural factors such as Latin masculinity.

Widespread and dynamic expression of granzyme C by skin-resident antiviral T cells.

After recognition of cognate antigen (Ag), effector CD8+ T cells secrete serine proteases called granzymes in conjunction with perforin, allowing granzymes to enter and kill target cells. While the roles for some granzymes during antiviral immune responses are well characterized, the function of others, such as granzyme C and its human ortholog granzyme H, is still unclear. Granzyme C is constitutively expressed by mature, cytolytic innate lymphoid 1 cells (ILC1s). Whether other antiviral effector cells also produce granzyme C and whether it is continually expressed or responsive to the environment is unknown. To explore this, we analyzed granzyme C expression in different murine skin-resident antiviral lymphocytes. At steady-state, dendritic epidermal T cells (DETCs) expressed granzyme C while dermal γδ T cells did not. CD8+ tissue-resident memory T cells (TRM) generated in response to cutaneous viral infection with the poxvirus vaccinia virus (VACV) also expressed granzyme C. Both DETCs and virus-specific CD8+ TRM upregulated granzyme C upon local VACV infection. Continual Ag exposure was not required for maintained TRM expression of granzyme C, although re-encounter with cognate Ag boosted expression. Additionally, IL-15 treatment increased granzyme C expression in both DETCs and TRM. Together, our data demonstrate that granzyme C is widely expressed by antiviral T cells in the skin and that expression is responsive to both environmental stimuli and TCR engagement. These data suggest that granzyme C may have functions other than killing in tissue-resident lymphocytes.

Antiviral Activities of Group I Innate Lymphoid Cells.

Even before the adaptive immune response initiates, a potent group of innate antiviral cells responds to a wide range of viruses to limit replication and virus-induced pathology. Belonging to a broader family of recently discovered innate lymphoid cells (ILCs), antiviral group I ILCs are composed of conventional natural killer cells (cNK) and tissue-resident ILCs (ILC1s) that can be distinguished based on their location as well as by the expression of key cell surface markers and transcription factors. Functionally, blood-borne cNK cells recirculate throughout the body and are recruited into the tissue at sites of viral infection where they can recognize and lyse virus-infected cells. In contrast, ILC1s are poised in uninfected barrier tissues and respond not through lysis but with the production of antiviral cytokines. From their frontline tissue locations, ILC1s can even induce an antiviral state in uninfected tissue to preempt viral replication. Mounting evidence also suggests that ILC1s may have enhanced secondary responses to viral infection. In this review, we discuss recent findings demonstrating that ILC1s provide several critical layers of innate antiviral immunity and the mechanisms (when known) underlying protection.