CXCR4 Lower in Women With HIV, Subclinical CVD
In women with HIV, reduced CXCR4 expression on non-classical monocytes was associated with subclinical carotid artery disease even after adjustment for confounders.
In women with HIV and subclinical cardiovascular disease (CVD), CXCR4 expression in non-classical monocytes is significantly lower compared with women without either HIV or CVD, according to study results published in Cardiovascular Research.
The findings suggested that CXCR4 has an athero-protective role in non-classical monocytes.
Participants from the Women's Interagency HIV Study (WIHS) (n=92) comprised the study cohort. The researchers stratified participants into four groups based on HIV and subclinical CVD status: HIV−/sCVD−, HIV−/sCVD+, HIV+/sCVD−, HIV+/sCVD+ (n=23 in each group). They determined 3 subsets of monocytes from archived peripheral blood mononuclear cells and used flow cytometry to count and phenotype surface markers. The researchers tested for differences based on HIV and subclinical CVD status.
The researchers did not find any differences in monocyte subset size between the four groups.
These results indicated that expression of 7 surface markers differed significantly across the 3 monocyte subsets. They found that CXCR4 expression, evaluated via median fluorescence intensity, in non-classical monocytes was highest in participants who did not have HIV or subclinical CVD (median 628; interquartile range [IQR] 295-1389). The next highest was found in participants with HIV but not subclinical CVD (median 486; IQR 248-699), followed by participants without HIV but who did have subclinical CVD (median 398; IQR 89-901), and finally, participants with both HIV and subclinical CVD (median 226; IQR 73-519; P =.006). CXCR4 expression on non-classical monocytes was also significantly higher in participants without subclinical CVD (median 501.5; IQR 249.5-887.3) compared with individuals with subclinical CVD (median 297; IQR 81.75-626.8; P =.028; n=46 per group).
The researchers found that CXCR4 expression on non-classical monocytes was significantly correlated with cardiovascular and HIV-related risk factors, including systolic blood pressure, platelet and T cell counts, and duration of antiretroviral therapy (P <.05).
“These findings highlight the important role for monocyte subsets in the progression of HIV-related cardiovascular pathology and need to be investigated in further large-scale studies,” the researchers concluded.
Mueller KAL, Hanna DB, Ehinger E, et al. Loss of CXCR4 on non-classical monocytes in participants of the Women's Interagency HIV Study (WIHS) with subclinical atherosclerosis [published online December 5, 2018]. Cardiovasc Res. doi:10.1093/cvr/cvy292