Impaired Granularity in T cell Subsets but not in B cell Favors the Carcinogenesis of the Breast: A Preliminary Study in Indonesian Women Cohort.

Objective: The progress made in cancer immunology has led to the development of innovative therapeutic strategies. However, despite these advances, the superficial characteristics of immune cells have been frequently overlooked: This oversight may be attributed to a limited understanding of the intricate relationships between immune cells and their microenvironment. This study seeks to address this limitation by comprehensively examining cell size and granularity in breast cancer (BC) patients and healthy donors (HD).

Methods: Peripheral blood mononuclear cell (PBMC) samples were isolated from BC patients and HD. We examined the size (FSC-A%rCV) and granularity (SSC-A%rCV) of immune cell subsets in both patient groups and HD using flowcytometry.

Results: Despite the absence of statistically significant variations in cell size between BC and HD, visual examination reveals noticeable discrepancies. There is a substantial decrease in granularity in CD8 and CD4 T-cell populations in BC compared to HD which is not observed in B cells.

Conclusion: Our analysis shows that while the size of immune cells may not be significantly altered in breast cancer patients compared to healthy donors, a closer examination of cell granularity reveals a distinct pattern. Specifically, the T-cell populations, including CD8 and CD4 cells, exhibit a substantial decrease in granularity in BC compared to HD. In contrast, B cells remain unaffected, suggesting that the granularity of T cells is uniquely susceptible to perturbations in breast cancer. This observation highlights the importance of considering cell granularity as a critical aspect of immune cell function, particularly in the context of cancer development.