Expression of TNF-alpha, IL-1beta, and IFN-gamma in Staphylococcus epidermidis slime-positive experimental endophthalmitis is closely related to clinical inflammatory scores.
OBJECTIVE
The purpose of this study was to investigate the expression of inflammatory cytokines TNF-alpha, IL-1beta, and IFN-gamma in the vitreous after experimentally induced endophthalmitis by a Staphylococcus epidermidis slime-producing strain.


METHODS
Seventy-two experimental Lewis rats received an intravitreal injection of 7000 viable organisms of Staphylococcus epidermidis slime-producing ATCC strain 35983, while 72 control rats received an intravitreal injection of sterile normal saline. Eyes were graded daily for signs of clinical inflammation and were removed 6, 12, 24, 48, 72 h, and 7 days after injection. Vitreous was obtained and titers of TNF-alpha, IL-1beta, and IFN-gamma were measured with established enzyme-linked immunosorbent assays.


RESULTS
In the experimental group, the clinical inflammatory score reached maximum (4+) within 24 h, while inflammation was almost abolished by day 7 (score 0-0.5+). Statistically increased levels of TNF-alpha and IL-1beta were detected in the experimental vitreous with maximum levels observed at 12 h. IFN-gamma was also detected in the experimental vitreous and reached maximum levels at 48 h. None of the cytokines examined was detected in sera at any time point in experimental or control rats.


CONCLUSIONS
The results of this study suggest that Staphylococcus epidermidis experimental endophthalmitis induces the expression of cytokines TNF-alpha, IL-1beta, and IFN-gamma in the vitreous. The time course of those cytokine expression levels is closely associated to the clinical presentation of this endophthalmitis model.
Department of Ophthalmology, University Hospitals of Geneva, 22 Alcide-Jentzer street, 1211, Geneva 14, Switzerland.
Ioannis K
IK
Petropoulos
Chrysoula V
CV
Vantzou
Fotini N
FN
Lamari
Nikolaos K
NK
Karamanos
Evangelos D
ED
Anastassiou
Nikolaos M
NM
Pharmakakis
D000818:Animals; D004195:Disease Models, Animal; D009877:Endophthalmitis / Q000378:metabolism* / Q000382:microbiology; D004797:Enzyme-Linked Immunosorbent Assay; D015818:Eye Infections, Bacterial / Q000378:metabolism* / Q000382:microbiology; D007371:Interferon-gamma / Q000378:metabolism*; D053583:Interleukin-1beta / Q000378:metabolism*; D008297:Male; D051381:Rats; D011917:Rats, Inbred Lew; D013203:Staphylococcal Infections / Q000378:metabolism* / Q000382:microbiology; D013212:Staphylococcus epidermidis / Q000502:physiology*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism*; D014822:Vitreous Body / Q000378:metabolism / Q000382:microbiology
D053583:Interleukin-1beta; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma