PBMCs were isolated from venous blood sample from drug-naive endemic normals (EN) and drug-deprived filarial lymphoedema (FL) individuals using density gradient centrifugation. Adhesion, transwell migration and in vitro matrigel assays were employed to characterise the lymphvasculogenic potential of PBMCs. CLPs were phenotypically characterised using flow cytometry; expression levels of lymphatic markers and inflammatory cytokines were quantified using qRT-PCR and ELISA, respectively.
PBMCs from FL group display poor adherence to fibronectin (P = 0.040), reduced migration towards SDF-1α (P = 0.035), impaired tubular network (P = 0.004) and branching point (P = 0.048) formation. The PBMC mRNA expression of VEGFR3 (P = 0.039) and podoplanin (P = 0.050) was elevated, whereas integrin α9 (P = 0.046) was inhibited in FL individuals; additionally, the surface expression of CD34 (P = 0.048) was significantly reduced in the FL group compared to the EN group.
PBMCs from filarial lymphoedema show defective and dysregulated lymphvasculogenic function compared to endemic normals.