An injectable antibacterial hydrogel to regulate ocular immune for endophthalmitis treatment

Bacterial endophthalmitis is a serious ocular infection and frequently results in vision loss or even blindness. Most of the present treatment methods are mainly embodied in strengthening the bactericidal effect, whereas the bacteria induced vigorous host immune response often leads to irreversible damage to eye tissue. Herein, we report an injectable hydrogel to treat endophthalmitis by killing invading bacteria and regulating ocular immunity. The designed hydrogel was formed by dynamic coordination crosslinking of sulfhydryl modified gelatin and silver ion while embedding the anti-CXCL1 antibody evenly. The injectable hydrogel can not only kill bacteria by releasing silver ions with its degradation, but also alleviate the bacteria-triggered excessive immune response via releasing anti-CXCL1 antibody to neutralize chemokine CXCL1, thus avoiding the host inflammatory response mediated bystander damage. Both in vitro and in vivo experiments showed that it has excellent ability against bacteria and immunomodulatory performance, preserving more integral retinal architecture and promoting visual recovery. This work may open up new avenues for combining antibacterial and immunotherapy in infectious endophthalmitis.