Riau Andri K, Mondal Debasish, Aung Thet T, Murugan Elavazhagan, Chen Liyan, Lwin Nyein C, Zhou Lei, Beuerman Roger W, Liedberg Bo, Venkatraman Subbu S, Mehta Jodhbir S
‡School of Materials Science and Engineering and △Center for Biomimetic Sensor Science, Nanyang Technological University, Singapore.
§Tissue Engineering and Stem Cell Research Group, ⊥Anti-Infectives Research Group, and #Ocular Proteomics Laboratory, Singapore Eye Research Institute, Singapore.
ACS Biomater Sci Eng. 2015 Dec 14;1(12):1324-1334. doi: 10.1021/acsbiomaterials.5b00396. Epub 2015 Nov 11.
Bacterial infection following implantation of an artificial corneal scaffold is a serious complication. Conventional antibiotic prophylaxis, which includes topical vancomycin application, is limited by low bioavailability, high dosing requirement, and poor patient compliance. The ideal option to overcome these issues is an antibiotic-eluting corneal prosthesis that sustains the local release of drug. In this study, we incorporated vancomycin in thick 15% collagen hydrogels to create an artificial corneal scaffold with anti-infective capability. The incorporation of vancomycin did not significantly alter the Young's modulus, transparency and refractive index of the vancomycin-loaded hydrogel (VH), which were 0.79 ± 0.04 MPa ( = 0.233 compared to blank hydrogel), 94.3 ± 2.3% ( = 0.115) and 1.346 ± 0.005 ( = 0.264), respectively. In vitro, the drug elution was sustained for up to 7 days. The VH was subsequently implanted intrastromally in rabbit corneas, replacing stromal tissue that was removed following femtosecond laser-assisted small incision lenticule extraction procedure. In vivo, the vancomcyin could be detected in the aqueous humor for up to 10 days. We then created a corneal infectious keratitis model by intrastromal injection of 1 × 10 CFU/ml of inoculate on day 2 postimplantation. On day 3 postinfection, the VH-implanted corneas were clear and nonedematous and showed a substantial reduction of log 2.5 in compared to the blank hydrogel-implanted corneas, which appeared hazy, edematous, and had excessive inflammation. Immunohistochemistry of inflammatory marker, CD18, demonstrated a significant reduction in inflammatory cells in VH-implanted corneas (49 ± 9 cells/unit area) compared to blank hydrogel-implanted corneas (523 ± 15 cells/unit area) ( < 0.001). In conclusion, we have demonstrated the efficacy of a drug-eluting corneal implant in preventing perioperative bacterial infections.
人工角膜支架植入后的细菌感染是一种严重的并发症。传统的抗生素预防措施,包括局部应用万古霉素,存在生物利用度低、给药剂量要求高和患者依从性差等局限性。克服这些问题的理想选择是一种能持续局部释放药物的抗生素洗脱角膜假体。在本研究中,我们将万古霉素掺入15%的厚胶原水凝胶中,制成具有抗感染能力的人工角膜支架。万古霉素的掺入并未显著改变载万古霉素水凝胶(VH)的杨氏模量、透明度和折射率,其杨氏模量、透明度和折射率分别为0.79±0.04兆帕(与空白水凝胶相比,P = 0.233)、94.3±2.3%(P = 0.115)和1.346±0.005(P = 0.264)。在体外,药物洗脱可持续长达7天。随后将VH基质内植入兔角膜,替代飞秒激光辅助小切口基质透镜切除术切除的基质组织。在体内,房水中可检测到万古霉素长达10天。然后,在植入后第2天通过基质内注射1×10⁶CFU/ml的接种物建立角膜感染性角膜炎模型。在感染后第3天,植入VH的角膜清晰且无水肿,与植入空白水凝胶的角膜相比,细菌数量对数减少了2.5,后者显得模糊、水肿且炎症过度。炎症标志物CD18的免疫组织化学显示,与植入空白水凝胶的角膜(523±15个细胞/单位面积)相比,植入VH的角膜中炎症细胞显著减少(49±9个细胞/单位面积)(P < 0.001)。总之,我们证明了一种药物洗脱角膜植入物在预防围手术期细菌感染方面的有效性。