The role of CD44-hyaluronic acid interaction in exogenous mesenchymal stem cells homing to rat remnant kidney.

Background/aims: The aim of our study was to reveal the role of CD44-Hyaluronic acid (HA) in the homing and improving renal function of systemically transplanted MSCs in chronic renal failure.

Methods: First, a remnant kidney model was established in rats and the expression of HA was determined using immunohistochemistry (IHC) and western blotting. Next, chemotaxis assay using flow cytometry, and cell migration assay of MSCs were performed in vitro. Then, MSCs were transplanted into rats, thus, sprague-Dawley (SD) rats were randomly divided into sham group, 5/6 nephrectomy (5/6 Nx) group, MSC group and MSC/Anti-CD44 group (n = 8 for all groups). Migration of MSCs to the kidney in these rats was assessed by using cell tracking experiments, and tissue damage was evaluated by morphological analysis using Masson's trichrome staining and periodic acid Schiff staining.

Results: HA was significantly observed in 5/6 Nx group, but not in sham group. Meanwhile, HA was discovered induced MSCs migration remarkably (p < 0.05) and anti-CD44 antibody inhibited the migration significantly (p < 0.05) in vitro. In vivo, the GFP-MSCs were observed in MSC group and the cells reduced in MSC/Anti-CD44 groups, especially, in the tubulointerstitium.

Conclusion: Our findings reveal that CD44-HA has the potential to induce MSCs homing to injured tissue, while its effect on the ability of MSCs, improving tissue function, is not significant.