Aging-associated and CD4 T-cell–dependent ectopic CXCL13 activation predisposes to anti–PD-1 therapy-induced adverse events
Hirotake Tsukamoto, Yoshihiro Komohara, Yusuke Tomita, Yuji Miura, Takanobu Motoshima, Kosuke Imamura, Toshiki Kimura, Tokunori Ikeda, Yukio Fujiwara, Hiromu Yano, Tomomi Kamba, Takuro Sakagami, Hiroyuki Oshiumi
Abstract
Clinical success of immune-checkpoint blockade (ICB) cancer immunotherapy is compromised by increased risk of immune-related adverse events (irAEs). However, mechanistic action(s) of immune responses underlying development of irAE remain not fully explored. Here, we found that in tumor-bearing aged, but not young, mice, antiprogrammed death receptor (PD)-1 therapy elicited irAE-like multiorgan dysfunctions with ectopic accumulation of T and B cells in damaged organs. In this preclinical model, the organ toxicities were mediated by immunoglobulin G (IgG) deposition because administration of IG from ICB-treated aged mice induced the pathogenicity specifically in naïve aged hosts. Mechanistically, CD4 T-cell–derived interleukin (IL)-21 upregulated B-cell–homing chemokine, CXCL13, preferentially in irAE organs from aged mice treated with anti–PD-1 therapy. The ICB-induced pathogenicity was alleviated by B-cell depletion or by blockade of IL-21 or CXCL13 activity. These results suggest that age-associated immune regulatory milieu contributes to the formation of tertiary lymphoid structure-like lymphocytic aggregates in irAE organs and irAE-related toxicity employing IL-21-CXCL13-auto-antibody axis. Supporting this, a systemic increase in CXCL13 and Il21 expression in CD4 T cells correlated with irAE incidence in ICB-treated patients. These findings provide rationale for therapeutic usefulness of CXCL13 in irAE management.