CD4(+) or CD8(+) T cells were isolated from diabetic LEW.1AR1-iddm rats or diabetes-resistant LEW.1AR1 rats. The primary step in the pathogenesis of diabetes mellitus is the activation of host T lymphocytes against specific antigens present on the patient’s beta cells. HLA-B15 is associated with IDDM in populations of Northern European and British origin, while B18 seems to replace B15 in Southern European populations. Patients with macrovascular disease also reported greater depressive symptomatology (P < 0.05). The overall prevalence of anti-GAD antibodies was 1.7% (2 of 121) in patients with previously undiagnosed NIDDM, whereas 1 of 100 controls had positive antibodies. Moreover, it should be possible to identify, from an early age, changes in the prediabetic period that persist to diagnosis and have predictive value. An evaluation of the treatment significance of estimation errors showed that the majority of errors were relatively benign. However, marked discordance between retinopathy and nephropathy occurs, as illustrated by patients with normal UAE or low-level microalbuminuria, normal glomerular structural measures, and advanced retinopathy. We conclude that adipose tissue lipolysis is normally exquisitely sensitive to insulin and that sensitivity, but not responsiveness to insulin, is impaired in poorly controlled IDDM. 10.4 ± 1.6 μmol · min−1 · kg−1; P < 0.05).