At-Risk and Recent-Onset Type 1 Diabetic Subjects Have Increased Apoptosis in the CD4+CD25+(high) T-Cell Fraction

BACKGROUND: In experimental models, Type 1 diabetes T1D can be prevented by adoptive transfer of CD4+CD25+ FoxP3+ suppressor or regulatory T cells. Recent studies have found a suppression defect of CD4+CD25+(high) T cells in human disease. In this study we measure apoptosis of CD4+CD25+(high) T cells to see if it could contribute to reduced suppressive activity of these cells. METHODS AND FINDINGS: T-cell apoptosis was evaluated in children and adolescent 35 females/40 males subjects comprising recent-onset and long-standing T1D subjects and their first-degree relatives, who are at variable risk to develop T1D. YOPRO1/7AAD and intracellular staining of the active form of caspase 3 were used to evaluate apoptosis. Isolated CD4+CD25+(high) and CD4+CD25− T cells were co-cultured in a suppression assay to assess the function of the former cells. We found that recent-onset T1D subjects show increased apoptosis of CD4+CD25+(high) T cells when compared to both control and long-standing T1D subjects p<0.0001 for both groups. Subjects at high risk for developing T1D 2–3Ab+ve show a similar trend p<0.02 and p<0.01, respectively. On the contrary, in long-standing T1D and T2D subjects, CD4+CD25+(high) T cell apoptosis is at the same level as in control subjects p = NS. Simultaneous intracellular staining of the active form of caspase 3 and FoxP3 confirmed recent-onset FoxP3+ve CD4+CD25+(high) T cells committed to apoptosis at a higher percentage 15.3±2.2 compared to FoxP3+ve CD4+CD25+(high) T cells in control subjects 6.1±1.7 p<0.002. Compared to control subjects, both recent-onset T1D and high at-risk subjects had significantly decreased function of CD4+CD25+(high) T cells p = 0.0007 and p = 0.007, respectively. CONCLUSIONS: There is a higher level of ongoing apoptosis in CD4+CD25+(high) T cells in recent-onset T1D subjects and in subjects at high risk for the disease. This high level of CD4+CD25+(high) T-cell apoptosis could be a contributing factor to markedly decreased suppressive potential of these cells in recent-onset T1D subjects

Apoptosis of CD4+CD25high T Cells in Type 1 Diabetes May Be Partially Mediated by IL-2 Deprivation

from T1D subjects. in T1D may be caught up in a relatively deficient cytokine milieu. function in subjects predisposed to T1D

The Importance of Artificial Intelligence in Upper Gastrointestinal Endoscopy

Recently, there has been a growing interest in the application of artificial intelligence (AI) in medicine, especially in specialties where visualization methods are applied. AI is defined as a computer’s ability to achieve human cognitive performance, which is accomplished through enabling computer “learning”. This can be conducted in two ways, as machine learning and deep learning. Deep learning is a complex learning system involving the application of artificial neural networks, whose algorithms imitate the human form of learning. Upper gastrointestinal endoscopy allows examination of the esophagus, stomach and duodenum. In addition to the quality of endoscopic equipment and patient preparation, the performance of upper endoscopy depends on the experience and knowledge of the endoscopist. The application of artificial intelligence in endoscopy refers to computer-aided detection and the more complex computer-aided diagnosis. The application of AI in upper endoscopy is aimed at improving the detection of premalignant and malignant lesions, with special attention on the early detection of dysplasia in Barrett’s esophagus, the early detection of esophageal and stomach cancer and the detection of H. pylori infection. Artificial intelligence reduces the workload of endoscopists, is not influenced by human factors and increases the diagnostic accuracy and quality of endoscopic methods

Figure 1

<p>Representative FACS pictures of CD4+CD25− and CD4+CD25+^high T cells using YOPRO1/7AAD method from representative subjects of clinical groups. Apoptosis was calculated as the percentage of apoptotic cells YOPRO1+ve/7AAD-ve amongst live cells total 7AAD-ve cells comprising both YOPRO1+ve and YOPRO1-ve cells. This is simply designated as YOPRO1+ve.</p

Figure 3

<p>Comparison of apoptosis measurement in the same subjects using two different methods. a CD4+CD25+^high T cells apoptosis in three clinical groups using YOPRO/7AAD stain combination; control subjects CD4+CD25+^high T cells apoptosis significantly differs from both recent-onset T1D and high at-risk subjects p = 0.0001 and p = 0.01, respectively. Apoptotic cells are presented on y-axis as YOPRO1+ve. b CD4+CD25+^high T cells apoptosis in the same subjects using intracellular staining of aaCas3. CD4+CD25+^high T cells apoptosis from control subjects significantly differs from both recent-onset T1D and high at-risk subjects p = 0.0006 and p = 0.009, respectively. Spearman's rank correlation coefficient between two apoptosis measurement methods in control and recent-onset T1D subjects is significant r = 0.59 and p = 0.0006. Apoptotic cells are presented on y-axis as aaCas3+ve.</p

Figure 5

<p>CD4+CD25+^high T cells suppressive potential across major clinical groups. Control subjects show statistically higher suppression compared to the other three groups recent-onset T1D, high at-risk and longstanding T1D subjects p = 0.0007, p = 0.007 and p = 0.04, respectively. Standardized suppression assay was performed with 1×10⁴ responder T cells, 10⁴ irradiated PBMCs 5000rad alone and in co-culture with CD4+CD25+^high T cells in 1∶10 ratio, stimulated with aCD3 coated beads 1ug/ml, 3 beads/per cell.</p

Impaired survival of peripheral T cells, disrupted NK/NKT cell development, and liver failure in mice lacking Gimap5

The loss of Gimap5 (GTPase of the immune-associated protein 5) gene function is the underlying cause of lymphopenia and autoimmune diabetes in the BioBreeding (BB) rat. The in vivo function of murine gimap5 is largely unknown. We show that selective gene ablation of the mouse gimap5 gene impairs the final intrathymic maturation of CD8 and CD4 T cells and compromises the survival of postthymic CD4 and CD8 cells, replicating findings in the BB rat model. In addition, gimap5 deficiency imposes a block of natural killer (NK)- and NKT-cell differentiation. Development of NK/NKT cells is restored on transfer of gimap5−/− bone marrow into a wild-type environment. Mice lacking gimap5 have a median survival of 15 weeks, exhibit chronic hepatic hematopoiesis, and in later stages show pronounced hepatocyte apoptosis, leading to liver failure. This pathology persists in a Rag2-deficient background in the absence of mature B, T, or NK cells and cannot be adoptively transferred by transplanting gimap5−/− bone marrow into wild-type recipients. We conclude that mouse gimap5 is necessary for the survival of peripheral T cells, NK/NKT-cell development, and the maintenance of normal liver function. These functions involve cell-intrinsic as well as cell-extrinsic mechanisms