Splenocytes from transgenic mice are not diabetogenic. A: ATs of splenocytes from 20- to 25-week-old Ins2-CCL21 NOD mice (100%, red, n = 12) or from age-matched diabetic nontransgenic mice (0%, black, n = 3, median transfer time 28 days) into 6-week-old NOD-scid mice. At least three donors per group, two recipients per donor, and 10 million cells per AT were used. ***P < 0.01. Experimental details are reported in Table 2. B: Quantification of CD44+ IGRP-reactive CTLs in pancreatic islets (P < 0.05) and in blood (P < 0.05) of 12-week-old Ins2-CCL21 NOD mice (n = 5) compared with nontransgenic littermate mice (n = 5). Pancreatic islets: Ins2-CCL21 NOD, 0.11 ± 0.3%; nontransgenic NOD, 4.64 ± 2.31%, P < 0.05. Blood: Ins2-CCL21 NOD, 0.10 ± 0.10%; nontransgenic NOD, 8.34 ± 9.68%, P < 0.05. C: Quantification of CD44+ INS-reactive CTLs in pancreatic islets (P < 0.05) and blood (P = 0.08) of 12-week-old Ins2-CCL21 NOD mice (n = 5) compared with nontransgenic littermate NOD mice (n = 5). Pancreatic islets: Ins2-CCL21 NOD, 1.23 ± 0.17%; nontransgenic NOD, 3.28 ± 1.04%, P = 0.01. Blood: Ins2-CCL21 NOD, 21.77 ± 10.66%; nontransgenic NOD, 10.82 ± 3.60%, P = 0.08. Data are indicated as % CD8+ cells. wks, weeks.