Functional NADPH oxidase 2 in T cells amplifies salt-sensitive hypertension and associated renal damage

Infiltrating T cells in the kidney amplify salt-sensitive (SS) hypertension and renal damage, but the mechanisms are not known. Genetic deletion of T cells (SS^CD247/) or of the p67^phox subunit of NADPH oxidase 2 (NOX2; SS^p67phox^/) attenuates SS hypertension in the Dahl SS rat. We hypothesized that reactive oxygen species produced by NOX2 in T cells drive the SS phenotype and renal damage. T cells were reconstituted by adoptively transferring splenocytes (10 million) from the Dahl SS (SSCD247) rat, the SS^p67phox^/ rat (p67^phoxCD247), or only PBS (PBSCD247) into the SS^CD247/ rat on postnatal day 5. Animals were instrumented with radiotelemeters and studied at 8 wk of age. There were no detectable differences in mean arterial pressure (MAP) or albuminuria between groups when rats were maintained on a low-salt (0.4% NaCl) diet. After 21 days of high-salt diet (4.0% NaCl), MAP and albuminuria were significantly greater in SSCD247 rats compared with p67^phoxCD247 and PBSCD247 rats. Interestingly, there was no difference between p67^phoxCD247 and PBSCD247 rats in albuminuria or MAP after 21 days. The lack of CD3⁺ cells in PBSCD247 rats and the presence of CD3⁺ cells in rats that received the T cell transfer demonstrated the effectiveness of the adoptive transfer. No differences in the number of CD3⁺, CD4⁺, or CD8⁺ cells were observed in the kidneys of SSCD247 and p67^phoxCD247 rats. These results indicate that reactive oxygen species produced by NOX2 in T cells participates in the amplification of SS hypertension and renal damage. NEW & NOTEWORTHY Our current work used the adoptive transfer of T cells that lack functional NADPH oxidase 2 into a genetically T cell-deficient Dahl salt-sensitive (SS) rat model. The results demonstrated that reactive oxygen species produced by NADPH oxidase 2 in T cells participate in the amplification of SS hypertension and associated renal damage and identifies a potential mechanism that exacerbates the salt-sensitive phenotype.