Panda Anita, Vanathi M, Kumar A, Dash Yeshoda, Priya Satya
Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India.
Surv Ophthalmol. 2007 Jul-Aug;52(4):375-96. doi: 10.1016/j.survophthal.2007.04.008.
Penetrating keratoplasty is the most widely practiced type of transplantation in humans. Irreversible immune rejection of the transplanted cornea is the major cause of human allograft failure in the intermediate and late postoperative period. This immunological process causes reversible or irreversible damage to the grafted cornea in several cases despite the use of intensive immunosuppressive therapy. Corneal graft rejection comprises a sequence of complex immune responses that involves the recognition of the foreign histocompatibility antigens of the corneal graft by the host's immune system, leading to the initiation of the immune response cascade. An efferent immune response is mounted by the host immune system against these foreign antigens culminating in rejection and graft decompensation in irreversible cases. A variety of donor- and host-related risk factors contribute to the corneal rejection episode. Epithelial rejection, chronic stromal rejection, hyperacute rejection, and endothelial rejection constitute the several different types of corneal graft rejection that might occur in isolation or in conjunction. Corneal graft failure subsequent to graft rejection remains an important cause of blindness and hence the need for developing new strategies for suppressing graft rejection is colossal. New systemic pharmacological interventions recommended in corneal transplantation need further evaluation and detailed guidelines. Two factors, prevention and management, are of significant importance among all aspects of immunological graft rejection. Preventive aspects begin with the recipient selection, spread through donor antigenic activity, and end with meticulous surgery. Prevention of corneal graft rejection lies with reduction of the donor antigenic tissue load, minimizing host and donor incompatibility by tissue matching and suppressing the host immune response. Management of corneal graft rejection consists of early detection and aggressive therapy with corticosteroids. Corticosteroid therapy, both topical and systemic, is the mainstay of management. Addition of immunosuppressive to the treatment regimen helps in quick and long term recovery. Knowledge of the immunopathogenesis of graft rejection may allow a better understanding of the immunological process thus helping in its prevention, early detection and management.
穿透性角膜移植术是人类中实施最为广泛的一种移植手术。移植角膜的不可逆免疫排斥是术后中期和后期同种异体移植失败的主要原因。尽管使用了强化免疫抑制疗法，但在某些情况下，这种免疫过程仍会对移植角膜造成可逆或不可逆的损害。角膜移植排斥反应包括一系列复杂的免疫反应，其中涉及宿主免疫系统识别角膜移植物的外来组织相容性抗原，从而引发免疫反应级联。宿主免疫系统会针对这些外来抗原发起传出免疫反应，在不可逆的情况下最终导致排斥和移植物失代偿。多种供体和宿主相关的危险因素会导致角膜排斥反应。上皮排斥、慢性基质排斥、超急性排斥和内皮排斥构成了几种不同类型的角膜移植排斥反应，这些反应可能单独出现或同时发生。移植排斥后导致的角膜移植失败仍然是失明的一个重要原因，因此开发抑制移植排斥的新策略的需求非常巨大。角膜移植中推荐的新的全身药理学干预措施需要进一步评估和详细的指导方针。在免疫移植排斥的各个方面中，预防和管理这两个因素非常重要。预防方面始于受体选择，贯穿供体抗原活性，最后以精细的手术结束。角膜移植排斥的预防在于减少供体抗原性组织负荷，通过组织配型使宿主和供体的不相容性最小化，并抑制宿主免疫反应。角膜移植排斥的管理包括早期检测和用皮质类固醇进行积极治疗。局部和全身使用皮质类固醇疗法是治疗的主要手段。在治疗方案中添加免疫抑制剂有助于快速和长期恢复。了解移植排斥的免疫发病机制可能有助于更好地理解免疫过程，从而有助于其预防、早期检测和管理。
