Effect of CAP10 gene on immune response in mice infected with Cryptococcus neoformans

ABSTRACT Background Capsule is an vital virulence factor in Cryptococcus neoformans infection. Recent studies show CAP10 is a key gene in capsular formation. However, the role of CAP10 in the pathophysiology of cryptococcosis is still not well understood. This study aims to investigate the association of CAP10 expression with the immune responses to infected mice. Methods The shRNA expression plasmid was designed to interfere with the synthesis of CAP10. The animal model was established with C. neoformans wt strain H99, cap10-shRNA C. neoformans and PBS control in the respiratory tract. On the 7 days and 21 days after infection, mice lung histopathological examination and homogenate culture were performed, and cytokines expression level in the serum of mice were quantitatively detected. Results The lower degree of edema and infiltration of inflammatory cells were observed in cap10-shRNA group. The growth rate of cap10-shRNA strain was significantly reduced. In addition, interference with CAP10 altered the expression profile of Th1, Th2, Th17 and Treg type cytokine. Down-regulation of CAP10 was beneficial to the balance of Th1/Th2, Th17/Treg ratio. Conclusions Taken together, our results indicated the expression of the CAP10 was associated with an antifungal immune response to mice infected with C. neoformans. CAP10 might play an important role in regulating the inflammatory response, and could expected to be a new molecular therapeutic target in cryptococcosis.