Differentiation of alloreactive versus CD3/CD28 stimulated T‐lymphocytes using Raman spectroscopy: A greater specificity for noninvasive acute renal allograft rejection detection

Acute rejection (AR) remains problematic in renal transplantation. As a marker, serum creatinine is limited, warranting a more effective screening tool. Raman spectroscopy (RS) can detect T‐cell activation with high sensitivity. In this study we explore its specificity. Seventy‐five inactivated, 40 alloantigen‐activated, and 75 CD3/CD28‐activated T cells were analyzed using RS. CD3/CD28‐activated peak magnitudes (PM) were 4.3% to 23.9% lower than inactivated PM at positions: 903, 1031, 1069, 1093, 1155, 1326, and 1449 cm −1 , with a difference in peak ratio (PR) observed at the 1182:1195 cm −1 position (0.91 ± 0.06 vs. 1.2 ± 0.01, respectively: P = 0.006). Differences in CD3/CD28‐ and alloantigen‐activated PM were observed at: 903, 1031, 1093, 1155, 1326, and 1449 cm −1 , with no PR differences at the 1182:1195 cm −1 position (0.91 ± 0.06 vs. 0.86 ± 0.09: P = 0.8). Spectral signature separation of CD3/CD28—and alloantigen‐activated groups was 100% specific and sensitive. We conclude that RS can differentiate T cells activated by different stimuli with high sensitivity and specificity. © 2009 International Society for Advancement of Cytometry