AIM: To explore whether adaptive immunity is involved in initiation of fungal keratitis(FK).

METHODS: Balb/c mice and severe combined T/B-null immunodeficiency(SCID)mice on same background were subjected to keratitis induction via intrastromal injection of 1×10⁵ Candida albican or Aspergillus fumigatus spores. The disease was monitored using slit-lamp and scored according to area and density of opacity and surface irregularity of the affected corneas. At desired time points, murine eyes were enucleated for histological examination by hematoxylin-eosin and Periodic acid Schiff staining. The number of live-fungi in corneal tissue was detected with colony forming assay, and the levels of IL17, IFNγ and IL10 in plasma and corneal tissue homogenate were evaluated by ELISA.

RESULTS: Both Balb/c mice and SCID mice developed typical keratitis when subjected to FK induction. Gross clinical presentation and disease scoring, as well as histology and pathogen load assay showed no significant difference between Balb/c mice and SCID mice with either pathogen. With the cytokine levels in either plasma or cornea, neither IL17 nor IFNγ showed significant difference between these two mouse strains, but IL10 was undetectable in any SCID mice though it could be detected in Balb/c mice, especially at early time points after FK induction.

CONCLUSION: The presence or absence of adaptive immunity compartment, at least in the studied Balb/c and SCID mice pairing, does not alter the course of primary FK, supporting the hypothesis that innate immunity component is more relevant with the pathogenesis of FK.