Targeted delivery of herpes simplex virus glycoprotein D to CD169 macrophages using ganglioside liposomes alleviates herpes simplex keratitis in mice.

Herpes simplex keratitis (HSK) is a common blinding corneal disease caused by herpes simplex virus type 1 (HSV-1) infection. Antiviral drugs and corticosteroids haven't shown adequate therapeutic efficacy. During the early stage of HSV-1 infection, macrophages serve as the first line of defense. In particular, CD169 macrophages play an important role in phagocytosis and antigen presentation. Therefore, we constructed GM-gD-lip, a ganglioside GM1 liposome vaccine encapsulating HSV-1 glycoprotein D and targeting CD169 macrophages. After subconjunctival injection of the vaccine, we evaluated the survival rate and ocular surface lesions of the HSK mice, as well as the virus levels in the tear fluid, corneas, and trigeminal ganglia. We discovered that GM-gD-lip reduced HSV-1 viral load and alleviated the clinical severity of HSK. The GM-gD-lip also increased the number of corneal infiltrating macrophages, especially CD169 macrophages, and polarized them toward M1. Furthermore, the number of dendritic cells (DCs) and CD8 T cells in the ocular draining lymph nodes was significantly increased. These findings demonstrated that GM-gD-lip polarized CD169 macrophages toward M1 to eliminate the virus while cross-presenting antigens to CD8 T cells via DCs to activate adaptive immunity, ultimately attenuating the severity of HSK. The use of GM-gD-lip as an immunotherapeutic method for the treatment of HSK has significant implications.