Abstract Body: Background:
Cardiovascular disease is more common in older individuals. At the same time, blood cell composition can change with age. The adult bone marrow is responsible for all blood cell production. Yet, it is not known how the bone marrow is altered in individuals with cardiovascular disease.
Methods:
We analyzed the bone marrow obtained from the sternum collected during cardiothoracic surgery. Bone marrow mononuclear cells from 75 patients were profiled using a 32-marker spectral flow cytometry panel. Multivariable linear regression was applied to assess independent associations between 16 clinical covariates and abundance of 30 immune cell populations adjusting for age, sex, BMI, smoking, and surgical context.
Results:
Age was independently associated with naive T cell depletion (31% of variance, p=0.006), and metabolic comorbidities were associated with expansion of immunosuppressive myeloid populations. Coronary artery disease, heart failure, and hypertension were each independently associated with significant depletion of total T cells, CD4+ T cells, CD8+ T cells, effector CD8+ T cells, and central memory CD8+ T cells (all p<0.05). In contrast, history of stroke was independently associated with significant expansion of total T cells (p<0.001), CD4+ T cells (p<0.001), effector CD8+ T cells ( p=0.014), B cells ( p<0.001), and innate lymphoid cells ( p<0.001). These data indicate varying immune changes in patients with cardiac disease.
Conclusion:
Our data illustrate noted differences that exist in the blood composition of patients with cardiac conditions. We identify acute lymphocyte mobilization and chronic immune exhaustion as distinct processes that may remodel the bone marrow immune compartment. These results uncover a previously unrecognized interplay between adult bone marrow blood production and cardiovascular disease.