HIV-associated preeclampsia: evaluation of lymphangiogenesis in placental bed samples

The role of angiogenesis in preeclampsia pathogenesis is widely studied; however, despite the lymphatic vessels' complementary role to the blood vascular system, studies on their morphology in the placenta and placental bed are lacking. In total, 87 placental bed specimens were utilized, which were grouped into normotensive pregnant (n = 28), early-onset preeclampsia (n = 31), and late-onset preeclampsia (n = 28), and further stratified by human immunodeficiency virus (HIV) status. Tissue was immunostained with podoplanin antibody to investigate whether HIV infection affects lymphangiogenesis. The lymphatic capillary density and luminal areas within the placental bed were morphometrically assessed. Lymphatic microvessel density and mean area/lumen in the preeclampsia group were higher and larger than in the normotensive group, respectively (p = 0.01 and p = 0.001). A correlation between blood pressure levels and lymphatic microvessel density was observed (r ≥ 0.272; p ≤ 0.032). Significant differences were observed between the mean microvessel density of normotensive HIV-uninfected and HIV-infected groups (5.9 ± 2.3 versus 7.5 ± 2.8, p = 0.01) and late-onset preeclampsia HIV-uninfected and HIV-infected groups (7.1 ± 3.9 versus 7.8 ± 2.7, p = 0.01). The mean area/lumen between normotensive HIV-uninfected and HIV-infected, and late-onset preeclampsia HIV-uninfected and HIV-infected groups were significantly different (p = 0.03 and p = 0.001). Small lymphatic capillaries were significantly abundant in late-onset preeclampsia HIV-infected (p = 0.03) and normotensive HIV-infected (p = 0.0001) groups compared with uninfected groups. Lymphatic capillary density and area/lumen upregulation was observed in the placental bed of HIV-infected women, with a positive correlation between maternal blood pressure and lymphatic microvessel density, potentially affecting birth weight in the preeclampsia group.