Role of conventional dendritic cells in schistosomiasis-induced pulmonary hypertension.

BACKGROUND

Schistosomiasis is a major cause of pulmonary hypertension (PH) worldwide, and CD4 T cells are critical in disease pathogenesis. The role of dendritic cells (DCs) in Schistosoma-induced PH (SchPH) is unknown. There are two types of conventional DCs, cDC1 and cDC2, that prototypically activate CD8 and CD4 T cells, respectively.

METHODS

We exposed wildtype, DC reporter, and DC knockout mice to Schistosoma mansoni and quantified PH severity by heart catheterization and cell density by flow cytometry.

RESULTS

Experimental S. mansoni exposure increased the density of pulmonary DCs, particularly cDC2s. Deleting both cDC subsets did not significantly modify SchPH disease severity. Deleting only cDC1s caused more severe SchPH, associated with more Th2 CD4 and CD8 T cells. In contrast, deleting only cDC2s reduced SchPH disease severity.

CONCLUSIONS

cDC1s appear to be protective, whereas cDC2s promote disease in SchPH.