Although immunotherapy research to date has focused largely on T cells, there is mounting evidence that tumour-infiltrating B cells and plasma cells (collectively referred to as tumour-infiltrating B lymphocytes (TIL-Bs)) have a crucial, synergistic role in tumour control. In many cancers, TIL-Bs have demonstrated strong predictive and prognostic significance in the context of both standard treatments and immune checkpoint blockade, offering the prospect of new therapeutic opportunities that leverage their unique immunological properties. Drawing insights from autoimmunity, we review the molecular phenotypes, architectural contexts, antigen specificities, effector mechanisms and regulatory pathways relevant to TIL-Bs in human cancer. Although the field is young, the emerging picture is that TIL-Bs promote antitumour immunity through their unique mode of antigen presentation to T cells; their role in assembling and perpetuating immunologically ‘hot’ tumour microenvironments involving T cells, myeloid cells and natural killer cells; and their potential to combat immune editing and tumour heterogeneity through the easing of self-tolerance mechanisms. We end by discussing the most promising approaches to enhance TIL-B responses in concert with other immune cell subsets to extend the reach, potency and durability of cancer immunotherapy.

尽管迄今为止的免疫疗法研究主要集中在 T 细胞上，但越来越多的证据表明肿瘤浸润 B 细胞和浆细胞（统称为肿瘤浸润 B 淋巴细胞 (TIL-Bs)）在肿瘤控制中具有至关重要的协同作用. 在许多癌症中，TIL-B 在标准治疗和免疫检查点封锁的背景下都显示出强大的预测和预后意义，提供了利用其独特免疫特性的新治疗机会的前景。我们从自身免疫中汲取见解，回顾了与人类癌症中 TIL-B 相关的分子表型、结构背景、抗原特异性、效应机制和调节途径。虽然这个领域很年轻，新出现的情况是，TIL-B 通过其独特的抗原呈递模式促进抗肿瘤免疫；它们在组装和维持涉及 T 细胞、骨髓细胞和自然杀伤细胞的免疫“热”肿瘤微环境中的作用；以及它们通过放松自我耐受机制来对抗免疫编辑和肿瘤异质性的潜力。最后，我们讨论了与其他免疫细胞亚群协同增强 TIL-B 反应以扩大癌症免疫疗法的范围、效力和持久性的最有希望的方法。以及它们通过放松自我耐受机制来对抗免疫编辑和肿瘤异质性的潜力。最后，我们讨论了与其他免疫细胞亚群协同增强 TIL-B 反应以扩大癌症免疫治疗的范围、效力和持久性的最有希望的方法。以及它们通过放松自我耐受机制来对抗免疫编辑和肿瘤异质性的潜力。最后，我们讨论了与其他免疫细胞亚群协同增强 TIL-B 反应以扩大癌症免疫治疗的范围、效力和持久性的最有希望的方法。