In vitro immunomodulatory capacity of Lactoferrin liposomes

Abstract

Purpose : LTF Lactoferrin (LTF) is an antimicrobial, immunomodulatory and anti-inflammatory protein and it has been advocated that LTF plays an important role at the ocular surface. Therefore, LTF liposomes have been produced in order to be applied as eyedrops and exert an immunomodulatory ocular response. LTF liposomes used in prophylaxis of cataract surgery showed to improve the physiological defenses and control bacterial ocular surface contamination. Now, to evaluate its role in the immune response after an exogenous stimulus in vitro assay was performed.

Methods : To assess immunomodulatory capacity, human corneal epithelial cells (HCE-2) were seeded and grown for 48 h. LPS was employed as inflammatory stimulus (10 μg/mL) to produce an immune response. Afterwards, treatments were applied for 24 h as prevention therapy and LPS was added for 24 h. Supernatants were collected and analyzed using ProcartaPlex. IL-8 a pro-inflammatory cytokine and Monocyte Chemoattractant Protein-1 (MCP-1) involved in the recruitment of macrophages were quantified.

Results : To evaluate the immunomodulatory capacity, IL-8 and MCP-1 were quantified and compared against free LTF and a control group (Figure 1). Regarding IL-8, both free LTF and LTF liposomes showed statistical differences against LPS (p<0.01 and p<0.005, respectively). No differences were obtained between free and encapsulated LTF in IL-8 values thus confirming that both possess ability to modulate the immune response. In addition, both free LTF and LTF liposomes decreased significantly MCP-1 against both LPS (p<0.0001) as well as against the healthy cells (p<0.0001). No differences were obtained between free and encapsulated LF confirming that in vitro both are able to modulate the immune response.

Conclusions : LTF liposomes did not cause cytotoxicity and possess an immunomodulatory response in vitro by preventing the release of inflammatory molecules such as IL-8 and MCP-1. Although further investigations are needed to assess the expression and modulation of other mediators involved and to better define the action of liposomal Lactoferrin at the ocular level, this study reports the immunomodulatory capacity of LTF liposomes and their capacity to control ocular inflammation processes.

This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.