Marchetti Piero, Antonelli Alessandro, Lupi Roberto, Marselli Lorella, Fallahi Poupak, Nesti Claudia, Baj Germano, Ferrannini Ele
Department of Endocrinology and Metabolism, University of Pisa, Pisa, Italy.
Diabetes. 2002 Dec;51 Suppl 3:S474-7. doi: 10.2337/diabetes.51.2007.s474.
Autoantibodies against CD38 (adenosine-5'-diphosphate[ADP]-ribosyl cyclase/cyclic ADP-ribose hydrolase) have been described in 10-12% of patients with type 2 diabetes. In human islets, anti-CD38 autoantibodies (CD38Abs) acutely stimulate insulin release (IR) and increase the cytosolic calcium concentration (Ca(2+)). Whether CD38Abs affect human islet cell function and survival upon prolonged in vitro exposure is not known. We cultured human islets for up to 7 days in the presence of sera from 10 patients with type 2 diabetes that had neither CD38Ab- nor Ca(2+)-mobilizing activity (-/-), sera from 6 patients with type 2 diabetes that was CD38Ab-positive and had Ca(2+)-mobilizing activity (+/+), or no sera (control). At baseline, +/+ sera caused a significant (P < 0.002) acute stimulation of IR (IR at 3.3 mmol/l glucose was 45 +/- 19, 84 +/- 24, and 34 +/- 12 micro U/ml in control, +/+, and -/- sera, respectively; the corresponding IR at 16.7 mmol/l glucose was 72 +/- 25, 204 +/- 56, and 80 +/- 32 micro U/ml). At 3 days, IR at 3.3 mmol/l glucose was 42 +/- 18, 27 +/- 11, and 43 +/- 24 micro U/ml (P = 0.0003) for control, +/+, and -/- sera, respectively, whereas at 16.7 mmol/l glucose, it was 95 +/- 76, 45 +/- 35, and 76 +/- 42 micro U/ml, respectively. After 7 days of exposure, the corresponding IR at 3.3 mmol/l glucose was 40 +/- 11, 28 +/- 12, and 35 +/- 15 micro U/ml, respectively, whereas at 16.7 mmol/l glucose it was 79 +/- 39, 39 +/- 17, and 62 +/- 39 micro U/ml. At both 3 and 7 days, IR still increased when switching from 3.3 to 16.7 mmol/l glucose (P < 0.0003), and incubation with +/+ sera induced a significant decrease in the insulin response (P < 0.002). At 7 days, the number of dead cells (as evaluated by an enzyme-linked immunosorbent assay technique) differed significantly between control (1.2 +/- 0.3 OD units) cells, islets exposed to -/- sera (1.4 +/- 0.1), and islets coincubated with +/+ sera (1.9 +/- 0.4, P < 0.01). We conclude that prolonged exposure of human islets to sera positive for the presence of CD38Abs with Ca(2+)-mobilizing activity impairs beta-cell function and viability in cultured human pancreatic islets.
在2型糖尿病患者中，10% - 12%的患者体内存在抗CD38（腺苷-5'-二磷酸[ADP] - 核糖基环化酶/环ADP - 核糖水解酶）自身抗体。在人胰岛中，抗CD38自身抗体（CD38Abs）可急性刺激胰岛素释放（IR）并增加胞质钙浓度（Ca(2 + )）。然而，长时间体外暴露时CD38Abs是否会影响人胰岛细胞功能和存活尚不清楚。我们用来自10例2型糖尿病患者的血清培养人胰岛长达7天，这些患者的血清既无CD38Ab也无Ca(2 + )动员活性（- / -），6例2型糖尿病患者的血清为CD38Ab阳性且具有Ca(2 + )动员活性（+ / +），或不添加血清作为对照。基线时，+ / +血清引起IR的显著（P < 0.002）急性刺激（对照、+ / +和 - / -血清中，3.3 mmol/l葡萄糖时的IR分别为45±19、84±24和34±12微U/ml；16.7 mmol/l葡萄糖时相应的IR分别为72±25、204±56和80±32微U/ml）。3天时，对照、+ / +和 - / -血清在3.3 mmol/l葡萄糖时的IR分别为42±18、27±11和43±24微U/ml（P = 0.0003），而在16.7 mmol/l葡萄糖时分别为95±76、45±35和76±42微U/ml。暴露7天后，3.3 mmol/l葡萄糖时相应的IR分别为40±11、28±12和35±15微U/ml，而在16.7 mmol/l葡萄糖时分别为79±39、39±17和62±39微U/ml。在3天和7天时，从3.3 mmol/l葡萄糖转换为16.7 mmol/l葡萄糖时IR仍会增加（P < 0.0003），并且与+ / +血清孵育会导致胰岛素反应显著降低（P < 0.002）。7天时，通过酶联免疫吸附测定技术评估的死细胞数量在对照（1.2±0.3 OD单位）细胞、暴露于 - / -血清的胰岛（1.4±0.1）和与+ / +血清共同孵育的胰岛（1.9±0.4，P < 0.01）之间存在显著差异。我们得出结论，人胰岛长时间暴露于具有Ca(2 + )动员活性的CD38Abs阳性血清会损害培养的人胰岛中β细胞的功能和活力。
