On Jan. 9, 2026, scientists at the Icahn School of Medicine at Mount Sinai, in partnership with the Multiple Myeloma Research Foundation (MMRF) and in collaboration with leading institutions across the country, have helped generate the largest single-cell immune cell atlas of the bone marrow in patients with multiple myeloma, a blood cancer that, while treatable, remains incurable. The findings, published in Nature Cancer, provide unprecedented insight on immune dysfunction in myeloma and could lead to improved tools for predicting which patients are at higher risk of relapse after treatment. 

The study analyzed nearly 1.5 million immune cells from the bone marrow of 335 newly diagnosed patients in the MMRF’s CoMMpass study dataset, using a cutting-edge technique called single-cell RNA sequencing. This approach allowed researchers to examine the molecular features of individual cells, revealing previously hidden patterns in how the immune system behaves in the presence of multiple myeloma. 

The team discovered that some patients who relapsed quickly after initial therapy had distinct immune cell populations in their bone marrow at the time of diagnosis. Notably, a subset of T cells (immune cells typically responsible for attacking tumors) appeared to show a state of immunosenescence, meaning they were present but not functioning effectively and contributing to immune suppression. In addition, the study uncovered patterns of communication between immune cells and cancer cells that may support tumor growth. 

These insights suggest that the immune system’s response to myeloma could be used as a predictive tool, offering a complementary layer to traditional genetic testing. While the current technology used in the study is primarily for research, the investigators hope the findings will inform the development of simple, broadly available tests in the future. 

The large patient sample size and robust clinical annotations—enabled by the MMRF’s extensive biorepository and 12 years of patient data—make this one of the most comprehensive resources of its kind. This report will significantly contribute to our understanding of immune function in multiple myeloma.