This mouse study evaluated whether oral probiotic *Limosilactobacillus reuteri* DSM 17938 (LR17938) could protect the ocular surface in a desiccating stress (DS) dry eye model, using antibiotic-induced dysbiosis mice and mice colonized with human gut microbiota from Sjögren's disease (SjD) or healthy donors.
LR17938 gavage improved corneal barrier function, preserved conjunctival goblet cell density, reduced corneal MMP-9 expression, increased T-regulatory cells, and decreased inflammatory T-cells in cervical lymph nodes; benefits held regardless of whether mice carried SjD or healthy human microbiota. Probiotic treatment did not significantly alter gut microbiome composition.
Preclinical mouse model only — results may not translate directly to humans. The study used antibiotic-induced dysbiosis, which is an artificial gut environment. No clinical endpoints (e.g., patient-reported symptoms, Schirmer's test) were assessed.
While still preclinical, oral *L. reuteri* DSM 17938 shows promise as a complementary approach for dry eye, particularly in the context of gut dysbiosis or Sjögren's disease. Clinicians should watch for forthcoming human trials before adopting this strategy.
