Alloimmune injury is a major cause of long-term kidney allograft failure whether due to functionally stable (subclinical) or overt clinical rejection. These episodes may be mediated by immune cells (cellular rejection) or alloantibody (antibody-mediated rejection). Early recognition of immune injury is needed for timely appropriate intervention to maintain graft functional viability. However, the conventional measure of kidney function (i.e., serum creatinine) is insufficient for immune monitoring due to limited sensitivity and specificity for rejection. As a result, there is need for biomarkers that more sensitively detect the immune response to the kidney allograft. Recently, several biomarkers have been clinically implemented into the care of kidney transplant recipients. These biomarkers attempt to achieve multiple goals including (1) more sensitive detection of clinical and subclinical rejection, (2) predicting impending rejection, (3) monitoring for the adequacy of treatment response, and (4) facilitating personalized immunosuppression. In this review, we summarize the findings to date in commercially available biomarkers, along with biomarkers approaching clinical implementation. While we discuss the analytical and clinical validity of these biomarkers, we identify the challenges and limitations to widespread biomarker use, including the need for biomarker-guided prospective studies to establish evidence of clinical utility of these new assays.

中文翻译：

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肾移植排斥反应的生物标志物。


同种免疫损伤是长期同种异体肾移植失败的主要原因，无论是由于功能稳定（亚临床）还是明显的临床排斥反应。这些发作可能由免疫细胞（细胞排斥反应）或同种抗体（抗体介导的排斥反应）介导。需要及早识别免疫损伤，以便及时进行适当干预以维持移植物的功能活力。然而，由于对排斥反应的敏感性和特异性有限，肾功能的常规测量（即血清肌酐）不足以进行免疫监测。因此，需要更灵敏地检测对同种异体肾移植物的免疫反应的生物标志物。最近，几种生物标志物已在临床上应用于肾移植受者的护理中。这些生物标志物试图实现多个目标，包括 （1） 更灵敏地检测临床和亚临床排斥反应，（2） 预测即将发生的排斥反应，（3） 监测治疗反应的充分性，以及 （4） 促进个性化免疫抑制。在这篇综述中，我们总结了迄今为止市售生物标志物的发现，以及接近临床实施的生物标志物。在我们讨论这些生物标志物的分析和临床有效性时，我们确定了生物标志物广泛使用的挑战和局限性，包括需要生物标志物指导的前瞻性研究来确定这些新检测的临床效用的证据。