Immunological circumvention of multiple organ metastases of multidrug resistant human small cell lung cancer cells by mouse-human chimeric anti-ganglioside GM2 antibody KM966

Antigen-Presenting Intratumoral B Cells Affect CD4+ TIL Phenotypes in Non-Small Cell Lung Cancer Patients

Effective immunotherapy options for patients with non-small cell lung cancer (NSCLC) are becoming increasingly available. The immunotherapy focus has been on tumor-infiltrating T cells (TILs); however, tumor-infiltrating B cells (TIL-Bs) have also been reported to correlate with NSCLC patient survival. The function of TIL-Bs in human cancer has been understudied, with little focus on their role as antigen-presenting cells and their influence on CD4⁺ TILs. Compared with other immune subsets detected in freshly isolated primary tumors from NSCLC patients, we observed increased numbers of intratumoral B cells relative to B cells from tumor-adjacent tissues. Furthermore, we demonstrated that TIL-Bs can efficiently present antigen to CD4⁺ TILs and alter the CD4⁺ TIL phenotype using an in vitro antigen-presentation assay. Specifically, we identified three CD4⁺ TIL responses to TIL-Bs, which we categorized as activated, antigen-associated, and nonresponsive. Within the activated and antigen-associated CD4⁺ TIL population, activated TIL-Bs (CD19⁺CD20⁺CD69⁺CD27⁺CD21⁺) were associated with an effector T-cell response (IFNγ⁺ CD4⁺ TILs). Alternatively, exhausted TIL-Bs (CD19⁺CD20⁺CD69⁺CD27^-CD21^-) were associated with a regulatory T-cell phenotype (FoxP3⁺ CD4⁺ TILs). Our results demonstrate a new role for TIL-Bs in NSCLC tumors in their interplay with CD4⁺ TILs in the tumor microenvironment, establishing them as a potential therapeutic target in NSCLC immunotherapy. Cancer Immunol Res; 5(10); 898-907. ©2017 AACR.

Genetically engineered humanized anti-ganglioside GM2 antibody against multiple organ metastasis produced by GM2-expressing small-cell lung cancer cells

Small-cell lung cancer (SCLC) grows rapidly and metastasizes to multiple organs. We examined the antimetastatic effects of the humanized anti-ganglioside GM2 (GM2) antibodies, BIW-8962 and KM8927, compared with the chimeric antibody KM966, in a SCID mouse model of multiple organ metastases induced by GM2-expressing SCLC cells. BIW-8962 and KM8927 induced higher antibody-dependent cellular cytotoxicity and complement-dependent cytotoxicity than KM966 against the GM2-expressing SCLC cell line SBC-3 in vitro. These humanized antibodies inhibited the production of multiple organ metastases, increased the number of apoptotic cells, and prolonged the survival of the SCID mice. Histological analyses using clinical specimens showed that SCLC cells expressed GM2. These findings suggest that humanized anti-GM2 antibodies could be therapeutically useful for controlling multiple organ metastases of GM2-expressing SCLC.