Toll-like Receptors Involved in the Pathogenesis of Experimental Candida albicans Keratitis

作者:Yuan Xiaoyong; Wilhelmus Kirk R*
来源:Investigative Ophthalmology & Visual Science, 2010, 51(4): 2094-2100.
DOI:10.1167/iovs.09-4330

摘要

PURPOSE. To investigate the expression and function of toll-like receptors (TLRs) during experimental keratomycosis.
METHODS. Scarified corneas of BALB/c mice were topically inoculated with Candida albicans and compared with control corneas by a murine gene microarray and immunostaining. Real-time reverse transcription polymerase chain reaction (RTPCR) determined relative TLR gene expression in murine and human donor corneas. The scarified corneas of TLR2(-/-) mice, TLR4(-/-) mice, and C57BL/6J control mice were also inoculated with C. albicans, to determine relative severity, fungal load, and cytokine transcript levels.
RESULTS. TLR1, -2, -4, -6, and -13 were significantly upregulated (5- to 10-fold; P < 0.01) by microarray, and TLR1, -2, -4, and -13 were significantly increased (4- to 11-fold; P < 0.05) by real-time RT-PCR in BALB/c murine corneas. Similarly, TLR2, -6, and -13 were significantly upregulated (5- to 16-fold; P <= 0.001) by real-time RT-PCR in C57BL/6J murine corneas the day after inoculation, and TLR2 and -13 remained significantly (P < 0.05) increased after 1 week. TLR2 transcript was also upregulated twofold (P = 0.04) in C. albicans-inoculated explanted human corneas. Although murine keratitis severity scores were similar, significantly more fungi were recovered from TLR2(-/-) mouse corneas (P = 0.04) than from TLR4(-/-) mouse corneas (P = 0.9). Tumor necrosis factor-alpha, interleukin 23, chemokine C-C ligands 3 and 4, and dectin-1 were significantly (P < 0.05) downregulated in C. albicans-infected corneas of TLR2(-/-) mice.
CONCLUSIONS. TLR2 signals proinflammatory cytokines that control fungal growth during C. albicans keratitis. TLR13 may have an additional role in the innate immune response of murine corneal candidiasis. (Invest Ophthalmol Vis Sci. 2010; 51: 2094-2100) DOI:10.1167/iovs.09-4330

  • 出版日期2010-4