METHODS: Genomic DNA was isolated from buffy coat for TCR and BCR clonotype profiling using the Immunoseq platform and diversity was quantified with Pielou\'s evenness index. MILLIPLEX MAP Human Cytokine/Chemokine Magnetic Bead Panel was used to measure serum cytokine levels, which were compared between groups using moderated t-statistic with Benjamini-Hochberg correction for multiple testing.
RESULTS: TCR and BCR diversity was high (Pielou\'s index > 0.75) in all samples. Baseline receptor diversities and change in diversity pre- and post-treatment were not associated with pathologic response or irAE status, except for BCR diversity that was significantly lower post-treatment in patients who developed irAE (unadjusted p = 0.0321). Five cytokines increased after treatment in patients with pathologic complete response (pCR) but decreased in patients with RD, most prominently IL-8. IFNγ, IL-7, and GM-CSF levels were higher in pre-treatment than in post-treatment samples of patients who developed irAEs but were lower in those without irAEs.
CONCLUSIONS: Baseline peripheral blood cytokine levels may predict irAEs in patients treated with immune checkpoint inhibitors and chemotherapy, and increased post-treatment B-cell clonal expansion might mediate irAEs.
方法:使用Immunoseq平台从血沉棕黄层中分离基因组DNA用于TCR和BCR克隆型分析,并使用Pielou的均匀度指数定量多样性。MILLIPLEXMAP人细胞因子/趋化因子磁珠面板用于测量血清细胞因子水平,使用适度的t统计量和Benjamini-Hochberg校正进行多重检验,在组间进行比较。
结果:所有样本中的TCR和BCR多样性都很高(Pielou指数>0.75)。治疗前后的基线受体多样性和多样性变化与病理反应或irAE状态无关。除了发生irAE的患者治疗后BCR多样性显着降低(未调整的p=0.0321)。5种细胞因子在病理完全缓解(pCR)患者治疗后增加,但在RD患者中减少。最突出的是IL-8。IFNγ,IL-7和GM-CSF水平在治疗前高于发生irAE的患者的治疗后样品,但在没有irAE的患者中更低。
结论:基线外周血细胞因子水平可以预测接受免疫检查点抑制剂和化疗的患者的irAE,治疗后B细胞克隆扩增增加可能介导irAE。