The Role of Tumour-Infiltrating Lymphocytes in the Immune Microenvironment of Lymphoma and Their Immunotherapeutic Potential

BACKGROUND: T cells, B cells and natural killer cells, play a key role in anti-tumour immune responses and modulate tumour immune escape via crosstalk with immunosuppressive factors in the tumour microenvironment. Despite inherent anti-tumour activity, TIL function is largely constrained by immune escape and cellular exhaustion. TILs also synergise with PD-1/PD-L1 and CTLA-4 to regulate the magnitude and persistence of anti-tumour immunity, and have emerged as valuable biomarkers for evaluating immunotherapeutic efficacy in lymphoma. METHODS: This review systematically summarises recent published literature regarding the biological function, immune regulatory mechanisms and clinical research progress of TILs in lymphoma. RESULTS: TILs exhibit promising potential in lymphoma immunotherapy, whereas TIL-based strategies remain challenged by complex cell preparation, unstable therapeutic efficacy and drug resistance. Further research is required to clarify TIL heterogeneity, characterise diverse immune escape mechanisms, and optimise clinical culture protocols. CONCLUSIONS: This review clarifies the pivotal role of TILs in the lymphoma immune microenvironment and their immunotherapeutic value. Optimising TIL culture conditions combined with gene editing and bioengineering will improve therapeutic efficacy and clinical applicability, offering novel insights for clinical treatment of lymphoma.