Objective  To evaluate the infection characteristics of several recombinant adeno-associated virus (rAAV) subtypes including rAAV1, rAAV2, rAAV2/8, and rAAV6 on cells within the mouse testis.

Methods  HEK293T cells were used for rAAV packaging. The viruses were inoculated via intratubular injection or testicular interstitial injection to the mice. On the 7th day postinoculation, testes were collected to make frozen sections after mice were sacrificed by cervical dislocation, and immunofluorescence staining was performed to examine and evaluate the infection and foreign protein expression of rAAV vectors to testicular cells.

Results  rAAV1, rAAV2 and rAAV6 subtypes were capable of infecting both sertoli cells and germ cells, with rAAV2 exhibiting a relative stronger infection capability on sertoli cells. rAAV2/8 demonstrated an infection preference specifically for sertoli cells when inoculated via the seminiferous tubules, while it specifically infected leydig cells when inoculated via testicular interstitia.

Conclusion  rAAV1 and rAAV6 did not show specific infection preference in testicular cells. rAAV2 displayed a relative preference towards sertoli cells though it was able to infect both germ cells and sertoli cells. rAAV2/8 was unable to penetrate the blood-testis barrier, showing specific infection on sertoli cells when inoculated via seminiferous tubules and on leydig cells when inoculated via testicular interstitia.

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