Abstract 14173: Activation of Cellular Immunity in Peripartum Cardiomyopathy: Results of the Multicenter IPAC Registry
Introduction: Peripartum Cardiomyopathy (PPCM) remains a major cause of maternal morbidity and mortality. Cellular immunity is downregulated during normal pregnancy and reset during the peripartum period. While pathogenic activation of cellular immunity may underlie PPCM, this has not been previously investigated. We evaluated cellular immune activation in PPCM subjects in the IPAC (Investigations in Pregnancy Associated Cardiomyopathy) study.
Method: IPAC investigated 31 PPCM subjects within 6 weeks post partum,8 normal postpartum women and 10 non-postpartum women. All controls had normal cardiac function by echocardiography. Peripheral blood was drawn at entry for assessment of T-cell, monocyte, and NK cell activation by flow cytometry. Cellular subsets were defined by forward and side scatter gates to identify lymphocytes and monocytes, and by the presence of specific antigens (T-cells: CD3, CD4, CD8; monocytes: CD14, CD16; NK cells: CD56, CD16), and cellular activation markers (HLADR, CD38 and CD25).
Results: The PPCM cohort was 40% NYHA class 3-4, 15% black, mean age 28±6, and LVEF 0.29±0.09, postpartum controls were 12.5% black, age 32±6, and nonperipartum controls were 10% black, mean age 38±6. Relative to normal peripartum women, PPCM patients had a significant (p<0.02) increase in activated double negative CD3+ T-cells (CD3+CD4-CD8-CD38+, a population of cells shown to have regulatory function); a significant decrease (p<0.04) in activated inflammatory monocytes (CD14+CD16+HLADR+), and a significant alteration in cells expressing NK cell markers (increased CD3-CD56+CD16-, p<0.04, suggesting activation of innate immunity; decreased CD3-CD56+CD16+, p<0.0001), with additional significant differences observed both between normal peripartum and normal non-postpartum, and between PPCM patients and normal non-postpartum.
Conclusion: Alterations in cellular immunity are clearly evident in PPCM patients relative to both normal postpartum women, and normal non-post partum controls. An increase in activation of regulatory T-cells (CD3+CD4-CD8-CD38+) and innate immunity (increased CD3-CD56+CD16- NK cells) may reflect activation of cellular immunity in PPCM patients.
- © 2011 by American Heart Association, Inc.