FABP-4，也稱為脂肪細胞脂肪酸結合蛋白 (A-FABP) 或 AP2，已被證明在肥胖和代謝綜合徵中起關鍵作用。儘管肥胖症增加，但 A-FABP 敲除小鼠基本上可以免受胰島素抵抗、血脂異常、2 型糖尿病和脂肪肝疾病的影響。
在臨床研究中，發現肥胖受試者的循環 A-FABP 水平升高，並且與非酒精性脂肪肝、中風和頸動脈粥樣硬化有關。
 

該測定是定量夾心ELISA。免疫板預先包被了對人 FABP4 具有特異性的小鼠單克隆抗體。標準品和样品被移入孔中，任何存在的人 FABP4 都被固定的抗體結合。洗去任何未結合的物質後，將生物素標記的特異於人 FABP4 的多克隆抗體添加到孔中。在去除任何未結合試劑的洗滌步驟後，加入鏈黴親和素-HRP 偶聯物，在最後一個洗滌步驟後，加入 HRP 底物溶液，顏色與最初結合的人 FABP4 的量成比例。 停止測定並使用酶標儀測定孔的光密度。由於吸光度的增加與捕獲的人 FABP4 的量成正比，因此可以從每個測定中包含的參考曲線中插入未知樣品濃度。

一種。 標準曲線的典型代表

以下標準曲線僅供演示。應為每組樣品測定生成標準曲線。 

B. 敏感性

該測定可檢測到的最低 FABP4 水平為 0.39 納克/毫升。

C. 特異性

該檢測中使用的抗體對人 FABP4 具有特異性，不會與小鼠和大鼠 FABP4 以及其他細胞因子或激素分子發生交叉反應。

D. 精度

測定內精密度（測定內的精密度）CV  <4.1%。

測定間精密度（測定之間的精密度）CV <4.5%。

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