美國食品和藥物管理局（FDA）8月20日批準了*鋅轉運體8自身抗體（ZnT8Ab）酶聯免疫吸附法（Elisa）檢測試劑盒，可用于幫助確定患者患有1型糖尿病，而不是其他類型的糖尿病。該款ZnT8Ab Elisa試劑盒由美國愛達荷州的自身免疫檢測專家Kronus公司研發。當與其他檢測方法及患者臨床資料配合使用時，ZnT8Ab Elisa試劑盒可能會幫助某些1型糖尿病患者得到及時的診斷和治療。

1型糖尿病是兒童和青少年中zui常見的糖尿病類型，但在某些情況下，成人也可能患1型糖尿病。1型糖尿病患者，因其免疫系統攻擊并破壞產生胰島素的胰腺β細胞，導致體內胰島素生成很少或沒有。胰島素（insulin）是一種激素，能夠將來源于食物的葡萄糖轉化為機體所需的能量。1型糖尿病患者需要注射胰島素來調節血糖水平，因為恰當的調節對于降低長期并發癥風險至關重要，包括失明、腎功能衰竭和心血管疾病。

許多1型糖尿病患者的免疫系統會產生鋅轉運體8自身抗體（ZnT8Ab），但其他類型糖尿病（2型糖尿病和糖尿病）患者體內不產生ZnT8Ab。該款ZnT8Ab Elisa試劑盒能夠檢測出患者血液中存在的ZnT8Ab。1型糖尿病的及早治療對于防止胰腺β細胞的進一步惡化至關重要。ZnT8Ab試劑盒可幫助患者得到及時的診斷，并幫助更早的啟動正確治療。

Kronus公司的ZnT8Ab Elisa試劑盒通過全面上市前（de novo premarket）審查途徑審查，該監管途徑用于一些與已上市設備無實質等效性的低-中風險醫療器械的審查。

FDA審查了一項涉及569份血樣的臨床研究的數據，其中323份來自確診1型糖尿病的血樣，ZnT8Ab Elisa試劑盒檢出ZnT8Ab的陽性率為65%；其余246份來自確診為其他類型糖尿病、自身免疫性疾病及其他臨床疾病的血樣，ZnT8Ab Elisa試劑盒檢出ZnT8Ab的假陽性率低于2%。

FDA指出，ZnT8Ab檢測結果陰性，并不能排除1型糖尿病。該款試劑盒不應用于監測疾病的階段或對治療的反應。

關于鋅轉運體8（ZnT8）及其自身抗體（ZnT8Ab）：

鋅是胰島素儲存和分泌機制中的一個重要組分，β細胞需要有效且特異的轉運體來累積足夠量的鋅。鋅轉運體8（ZnT8）是新近發現的一種1型糖尿病自身抗原，具有高度β細胞特異性，通過影響鋅離子濃度而在胰島素合成和分泌中發揮重要作用。ZnT8自身抗體對自身免疫性糖尿病（尤其對其他自身抗體陰性者）有著重要的診斷與預測價值。ZnT8基因（SLC30A8基因）多態性影響ZnT8自身抗體的特異性。（生物谷Bioon.com）

英文原文：FDA allows marketing of first ZnT8Ab autoantibody test to help diagnose type 1 diabetes

Today, the U.S. Food and Drug Administration allowed marketing of the first zinc transporter 8 autoantibody (ZnT8Ab) test that can help determine if a person has type 1 diabetes and not another type of diabetes. When used with other tests and patient clinical information, the test may help some people with type 1 diabetes receive timely diagnosis and treatment for their disease.

Type 1 diabetes is the most common type of diabetes diagnosed in children and adolescents, but in some instances it may also develop in adults. People with the disease produce little or no insulin because their immune system attacks and destroys the cells in the pancreas that produce insulin, a hormone that converts sugars (glucose) in food to the energy the bodyneeds. People with type 1 diabetes mustinject insulinto regulate their blood glucose because proper regulation is critical to lower their risk of long-term complications such as blindness, kidney failure and cardiovascular disease.

The immune system of many people with type 1 diabetes produces ZnT8Ab, but patients with other types of diabetes (type 2 and gestational) do not. The KRONUS Zinc Transporter 8 Autoantibody (ZnT8Ab) ELISA Assay detects the presence of the ZnT8 autoantibody in a patient’s blood.

“Early treatment of type 1 diabetes is important in helping to prevent further deterioration of insulin producing cells,” said Alberto Gutierrez, Ph.D., director of the Office of In Vitro Diagnostics and Radiological Health in the Center for Devices and Radiological Health at the FDA. “This test can help patients get a timely diagnosis and help start the right treatment sooner.”

The KRONUS ZnT8Ab ELISA Assay was reviewed through the de novo premarket review pathway, a regulatory pathway for some low- to moderate-risk medical devices that are not substantially equivalent to an already legally marketed device.

The agency reviewed data from a clinical study of 569 blood samples -- 323 from patients with diagnosed type 1 diabetes and 246 samples from patients diagnosed with other kinds of diabetes, other autoimmune diseases, and other clinical conditions. The test was able to detect the ZnT8 autoantibody in 65 percent of the samples from patients with diagnosed type 1 diabetes and incorrectly gave a positive result in less than two percent of the samples from patients diagnosed with other disease.

A negative result from the test does not rule out a diagnosis of type 1 diabetes. The test should not be used to monitor the stage of disease or the response to treatment.

KRONUS Zinc Transporter 8 Autoantibody (ZnT8Ab) ELISA Assay is manufactured by KRONUS Market Development Associates, Inc. in Star, Idaho.