Impact of afatinib on intestinal and salivary IgA: Immune response alterations linked to gastrointestinal side effects.

BACKGROUND

Afatinib, an oral molecular-targeted anticancer agent, is effective but causes significant gastrointestinal side effects. These effects are associated with EGFR inhibition in intestinal cells and changes in the microbiota.

OBJECTIVE

To investigate the effects of afatinib on intestinal mucosal immunity in rats, focusing on IgA levels in the intestine and saliva, and to understand the innate and acquired immune responses to these side effects.

METHODS

Male Wistar rats received afatinib (5.2 mg/kg) daily for 24 h (Day 1) and for 2 weeks (Day 14). Gene expression in the intestine was analyzed using quantitative polymerase chain reaction. IgA levels in the intestine and saliva were measured using enzyme-linked immunosorbent assay.

RESULTS

Afatinib suppressed α-defensin 5 and pIgR in the jejunum and ileum, indicating reduced innate immunity. It increased IgA levels in the intestine and saliva, suggesting altered acquired immunity. Salivary IgA levels significantly correlated with intestinal IgA levels.

CONCLUSIONS

Afatinib affects gastrointestinal mucosal immunity, suppresses innate defense, and alters IgA production. Salivary IgA could serve as a marker for monitoring these effects, aiding cancer therapy management.