XCL1 and infection: Figure 6A shows that XCL1 was unable to capture VSV-G pseudotyped virions, indicating the HIV-1 capture observed in Figure 5A required the presence of the HIV-1 envelope. To verify the relevance of these observations to the antiviral activity of XCL1, we performed acute infection assays with VSV-G pseudotyped virions in primary PBMC. We did not observe any inhibitory effect of XCL1, as evidenced by measuring both the absolute numbers of infected cells (Figure 6B), and the levels of reporter gene (GFP) expression within the gated population of infected cells (Figure S3).