Abstract:
Evolution of SARS-CoV-2 in immunocompromised hosts may result in novel variants with changed properties. While escape from humoral immunity certainly contributes to intra-host evolution, escape from cellular immunity is poorly understood. Here, we report a case of long-term COVID-19 in an immunocompromised patient with non-Hodgkin’s lymphoma who received treatment with rituximab and lacked neutralizing antibodies.
Over the 318 days of the disease, the SARS-CoV-2 genome gained a total of 40 changes, 34 of which were present by the end of the study period. Among the acquired mutations, 12 reduced or prevented the binding of known immunogenic SARS-CoV-2 HLA class I antigens. By experimentally assessing the effect of a subset of the escape mutations, we show that they resulted in a loss of as much as ~1% of effector CD8 T cell response. Our results indicate that CD8 T cell escape represents a major underappreciated contributor to SARS-CoV-2 evolution in humans.
Source: Stanevich OV, Alekseeva EI, Sergeeva M, Fadeev AV, Komissarova KS, Ivanova AA, Simakova TS, Vasilyev KA, Shurygina AP, Stukova MA, Safina KR, Nabieva ER, Garushyants SK, Klink GV, Bakin EA, Zabutova JV, Kholodnaia AN, Lukina OV, Skorokhod IA, Ryabchikova VV, Medvedeva NV, Lioznov DA, Danilenko DM, Chudakov DM, Komissarov AB, Bazykin GA. SARS-CoV-2 escape from cytotoxic T cells during long-term COVID-19. Nat Commun. 2023 Jan 10;14(1):149. doi: 10.1038/s41467-022-34033-x. PMID: 36627290; PMCID: PMC9831376. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9831376/ (Full text)