Sex Differences in RANTES (CCL5) in Patients With Intermediate Age-Related Macular Degeneration (AMD) and Controls With no AMD.

PURPOSE: To determine if there are sex differences in levels of regulated upon activation, normal T cell expressed and secreted (RANTES) in patients with intermediate age-related macular degeneration (iAMD) and in controls with no AMD. METHODS: Patients with iAMD and controls defined by multi-modal imaging were recruited into a Colorado AMD registry. Plasma levels of the chemokine RANTES were measured using a multiplex assay. A nonparametric (rank-based) regression model was fit to RANTES with a sex by AMD category interaction. RESULTS: The plasma level of RANTES was significantly higher in the control group in comparison with the iAMD group. When moderated by sex, RANTES was significantly lower (P = 0.005) in males (median, 4525.6 pg/mL; interquartile range, 2589-7861 pg/mL) compared with females (median, 6686 pg/mL; interquartile range, 3485-12488 pg/mL) within the iAMD cohort. No significant difference was found in levels of RANTES between males and females in the control group. CONCLUSIONS: We found that levels of RANTES were moderated by sex in cases with iAMD with lower levels in males compared with females. The findings illustrate the importance of including sex as a biological variable in AMD research. There is a need for further studies of RANTES, stratified by sex, in the advanced phenotypes of AMD. TRANSLATIONAL RELEVANCE: The biomarker RANTES identified in the plasma of patients with iAMD reflects systemic alterations when stratified by sex.