Since it was cleared as an in vitro assessment of cell-mediated immunity in immunosuppressed patient populations, numerous clinical investigations have contributed to defining the role of the Cylex ImmuKnow assay among recipients of solid organ transplants. In the largest immune monitoring experience in heart transplantation, investigators at UCLA’s David Geffen School of Medicine followed 337 cardiac transplant patients with ImmuKnow to determine whether ImmuKnow assay values can be correlated with the incidence of infection or rejection. The lead investigator, Jon Kobashigawa, MD, favorably remarked, “These results suggest that ImmuKnow as a non-invasive immune monitoring is indeed a promising means for individualizing immunosuppression in heart transplant recipients.” “This study expands our understanding of the applicability of the ImmuKnow immune function assay in effective management of heart transplant recipients in the post-transplant setting,” stated Dr. Kobashigawa. Additionally, Kobashigawa and his colleagues conclude that the noninvasive ImmuKnow assay appears to predict infection with the promise of balancing risk of infection and rejection in heart transplant patients pending additional larger studies. As described in this study, the use of the ImmuKnow assay for identifying patients at risk for infection or rejection following heart transplantation has not been cleared by the US Food & Drug Administration. The company may use data from this or similar studies to support future FDA marketing applications.