Role of TLR1 and TLR6 in the host defense against disseminated candidiasis

Abstract

Toll-like receptor-1 (TLR1) and TLR6 are receptors of the TLR family that form heterodimers with TLR2. The role of TLR1 and TLR6 for the recognition of the fungal pathogen Candida albicans was investigated. TLR1 is not involved in the recognition of C. albicans, and TLR1 knock-out (TLR1 À/À) mice showed a normal susceptibility to disseminated candidiasis. In contrast, recognition of C. albicans by TLR6 modulated the balance between Th1 and Th2 cytokines, and TLR6 knock-out mice displayed a defective production of IL-10 and an increased IFN-g release. Production of the monocyte-derived cytokines tumor necrosis factor, IL-1, and IL-6 was normal in TLR6 À/À mice, and this was accompanied by a normal susceptibility to disseminated candidiasis. In conclusion, TLR6 is involved in the recognition of C. albicans and modulates the Th1/Th2 cytokine balance, but this results in a mild phenotype with a normal susceptibility of TLR6 À/À mice to Candida infection.

Histones from Dying Renal Cells Aggravate Kidney Injury via TLR2 and TLR4

“…C57BL/6J mice, 6-12 weeks old, genetically deficient (.F6) in Tlr1, 37 Tlr2, 22 Tlr4, 22 Cd14, 38 Tlr6, 37 Rage, 39 Myd88, 40 or Trif 41 have been described. Tlr2-and Tlr4-deficient mice were crossed to produce Tlr2/4 double-deficient mice.…”

The role of pattern recognition receptors in the innate recognition ofCandida albicans

“…145 TLR1 was indicated not involved in the recognition of C. albicans, while TLR6 might play a role in modulating the balance between Th1 and Th2 cytokines. 146 The TLR6 knock-out mice displayed a defective production of IL-10 and an increased IFN-g release. 146 These results indirectly suggest that DCs might regulate adaptive immunity through TLR6.…”

“…146 The TLR6 knock-out mice displayed a defective production of IL-10 and an increased IFN-g release. 146 These results indirectly suggest that DCs might regulate adaptive immunity through TLR6. Whether the phagosomal TLRs (such as TLR3 and TLR7) on DCs were involved in recognizing RNA of C. albicans is still unclear.…”

Fungal killing by mammalian phagocytic cells

“…Galectin-3 is a β-1,2 mannan receptor that specifically recognizes the pathogenic yeast C. albicans but not the non-pathogenic Saccharomyces cerevisiae [11] and to exerts direct fungicidal effect [12]. TLR1 and TLR6, known to form heterodimers with TLR2, have been recently shown to have no or mild effect on macrophage recognition of C. albicans [13].…”