Association between α4β7 expression and HIV seroconversion. Differences measured in percent of α4β7hiCD4+ T cells between cases and controls in MSM (A) and PWID (B). Statistical analysis was done using conditional logistic regression between matched cases and controls. (ns-nonsignificant; *-p < 0.05, by conditional logistic regression). PWID in the ALIVE study were matched on age group, race, injection drug use in the past six months. For MSM and transgender women in the HVTN 505 vaccine trial, the multivariable model was adjusted for age, race/ethnicity, behavioral risk score, and vaccine group (per protocol). For PWID in the ALIVE study, the multivariable model was adjusted for age (continuous), sex, injection cocaine use in the past six months, and number of sexual partners in the past six months.