TSP-1 Deficiency Alters Ocular Microbiota: Implications for Sjögren's Syndrome Pathogenesis.
OBJECTIVE
The potential role of commensals as triggering factors that promote inflammation in dry eye disease has not been explored. The objective of this study was to evaluate whether ocular microbiota changes with the onset of dry eye disease in thrombospondin-1-deficient (TSP-1(-/-)) mice, a strain that develops Sjögren's syndrome-like disease.


METHODS
Conjunctival swabs were collected from TSP-1(-/-) and C57BL/6 mice and analyzed for bacterial presence. Opsonophagocytosis of the bacterial conjunctival isolates derived from the aged TSP-1(-/-) mice by neutrophils derived from either TSP-1(-/-) or C57BL/6 bone marrow was evaluated. The bactericidal activities of TSP-1-derived peptide were examined.


RESULTS
We found that in TSP-1(-/-) mice, the conjunctival colonization with Staphylococcus aureus and coagulase negative staphylococci sp (CNS) species was significantly increased with aging and preceded that of the wild-type C57BL/6 control mice. This correlated with increased neutrophil infiltration into the conjunctiva of the TSP-1(-/-) mice, suggesting that TSP-1 plays a significant role in regulating immunity to commensals. Accordingly, the TSP-1(-/-) PMNs opsonophagocytozed the ocular commensals less efficiently than the TSP-1-sufficient neutrophils. Furthermore, a TSP-1-derived peptide, 4N1K, exhibited significant antimicrobial activity when compared to a control peptide against commensal sp.


CONCLUSIONS
These studies illustrate that alterations in the commensal frequency occur in the early stages of development of Sjögren's-like pathology and suggest that interventions that limit commensal outgrowth such as the use of TSP-1-derived peptides could be used for treatment during the early stages of the disease to reduce the commensal burden and ensuing inflammation.
1 Division of Infectious Diseases, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School , Boston, MA.
Marielle
M
Terzulli
2 Department of Ophthalmology, Boston University , School of Medicine, Boston, MA.
Laura
L
Contreras-Ruiz
Laura Contreras
LC
Ruiz
1 Division of Infectious Diseases, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School , Boston, MA.
Abirami
A
Kugadas
2 Department of Ophthalmology, Boston University , School of Medicine, Boston, MA.
Sharmila
S
Masli
1 Division of Infectious Diseases, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School , Boston, MA.
Mihaela
M
Gadjeva
D000818:Animals; D004195:Disease Models, Animal; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005123:Eye / Q000382:microbiology; D007249:Inflammation / Q000382:microbiology / Q000473:pathology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D064307:Microbiota; D012859:Sjogren's Syndrome / Q000209:etiology / Q000378:metabolism* / Q000382:microbiology* / Q000473:pathology; D013211:Staphylococcus aureus / Q000254:growth & development; D019700:Thrombospondin 1 / Q000172:deficiency*
D019700:Thrombospondin 1; C585483:Thbs1 protein, mouse