Thymosin β4 Alleviates Autoimmune Dacryoadenitis via Suppressing Th17 Cell Response

Area of Science:

• Ophthalmology
• Immunology
• Pharmacology

Background:

• Autoimmune dacryoadenitis, a model for Sjögren's syndrome dry eye, causes significant ocular discomfort.
• Understanding therapeutic targets for dry eye disease is crucial for improving patient outcomes.

Purpose of the Study:

• To investigate the therapeutic potential of recombinant thymosin β4 (rTβ4) in a rabbit model of autoimmune dacryoadenitis.
• To elucidate the underlying mechanisms of rTβ4's action on ocular inflammation and T helper 17 (Th17) cell responses.

Main Methods:

• Rabbits with induced autoimmune dacryoadenitis received topical rTβ4 or PBS treatment.
• Clinical scores, tear secretion, and ocular surface integrity were assessed.
• Gene and protein expression of inflammatory mediators and Th17-related factors (e.g., RORC, IL-17) were analyzed using RT-PCR and Western blotting.

Main Results:

• Topical rTβ4 significantly ameliorated clinical symptoms and ocular surface inflammation.
• rTβ4 suppressed the expression of key Th17-related genes and IL-17 protein in lacrimal glands.
• rTβ4 inhibited signal transducer and activator of transcription 3 (STAT3) phosphorylation, a key pathway in Th17 activation.

Conclusions:

• rTβ4 demonstrates therapeutic efficacy in alleviating autoimmune dacryoadenitis.
• The mechanism involves the suppression of Th17 responses, partly through modulation of the STAT3 pathway.
• rTβ4 offers a potential new therapeutic strategy for dry eye disease associated with Sjögren's syndrome.