Transcriptomic responses of cumulus granulosa cells to SARS-CoV-2 infection during controlled ovarian stimulation

Cumulus granulosa cells (CGCs) play a crucial role in follicular development, but so far, no research has explored the impact of SARS-CoV-2 infection on ovarian function from the perspective of CGCs. In the present study, we compared the cycle outcomes between infected and uninfected female patients undergoing controlled ovarian stimulation, performed bulk RNA-sequencing of collected CGCs, and used bioinformatic methods to explore transcriptomic changes. The results showed that women with SARS-CoV-2 infection during stimulation had significantly lower number of oocytes retrieved and follicle-oocyte index, while subsequent fertilization and embryo development were similar. CGCs were not directly infected by SARS-CoV-2, but exhibited dramatic differences in gene expression (156 up-regulated and 65 down-regulated). Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses demonstrated a high enrichment in antiviral, immune and inflammatory responses with necroptosis. In addition, the pathways related to telomere organization and double strand break repair were significantly affected by infection in gene set enrichment analysis. Further weighted gene co-expression network analysis identified a key module associated with ovarian response traits, which was mainly enriched as a decrease of leukocyte chemotaxis and migration in CGCs. For the first time, our study describes how SARS-CoV-2 infection indirectly affects CGCs at the transcriptional level, which may impair oocyte-CGC crosstalk and consequently lead to poor ovarian response during fertility treatment.