Innate Immune Interference Attenuates Inflammation In Bacillus Endophthalmitis

Area of Science:

• Ophthalmology
• Immunology
• Microbiology

Background:

• Bacillus endophthalmitis is a severe intraocular infection.
• The innate immune system plays a critical role in the inflammatory response to bacterial infections.
• Current treatments, including corticosteroids, are often insufficient for Bacillus endophthalmitis.

Purpose of the Study:

• To investigate the impact of innate immune pathway interference on intraocular inflammation during Bacillus endophthalmitis.
• To identify specific genes and pathways affected by innate immune modulation in this condition.

Main Methods:

• Bacillus endophthalmitis was induced in a mouse model.
• Innate immune activation was inhibited using a S layer protein-deficient Bacillus thuringiensis strain or a TLR2/4 inhibitor.
• Gene expression in infected and treated eyes was analyzed using a NanoString murine inflammation panel.

Main Results:

• Innate immune interference significantly reduced the expression of numerous inflammatory genes, including cytokines, chemokines, and complement factors.
• Key innate pathway genes such as TLRs, MyD88, NF-κB, and inflammasome components showed blunted expression upon interference.
• Specific gene expression reductions were observed in both the S layer protein-deficient Bacillus thuringiensis infected group and the TLR2/4 inhibitor treated group compared to wild-type infected eyes.

Conclusions:

• Interference with innate immune activation effectively dampens the intraocular inflammatory response in Bacillus endophthalmitis.
• This approach presents a promising therapeutic strategy for Bacillus endophthalmitis, an infection often resistant to conventional treatments like corticosteroids.