Effect of Culture Supernatant Derived from Trichophyton Rubrum Grown in the Nail Medium on the Innate Immunity-related Molecules of HaCaT

Chin Med J (Engl). 2015 Nov 20;128(22):3094-100. doi: 10.4103/0366-6999.169106.

Abstract

Background: Trichophyton rubrum is superficial fungi characteristically confined to dead keratinized tissues. These observations suggest that the soluble components released by the fungus could influence the host immune response in a cell in contact-free manner. Therefore, this research aimed to analyze whether the culture supernatant derived from T. rubrum grown in the nail medium could elicit the immune response of keratinocyte effectively.

Methods: The culture supernatants of two strains (T1a, T XHB ) were compared for the β-glucan concentrations and their capacity to impact the innate immunity of keratinocytes. The β-glucan concentrations in the supernatants were determined with the fungal G-test kit and protein concentrations with bicinchoninic acid protein quantitative method, then HaCaT was stimulated with different concentrations of culture supernatants by adopting morphological method to select a suitable dosage. Expressions of host defense genes were assessed by quantitative polymerase chain reaction after the HaCaT was stimulated with the culture supernatants. Data were analyzed with one-way analysis of variance, followed by the least significant difference test.

Results: The T. rubrum strains (T1a and T XHB ) released β-glucan of 87.530 ± 37.581 pg/ml and 15.747 ± 6.453 pg/ml, respectively into the media. The messenger RNA (mRNA) expressions of toll-like receptor-2 (TLR2), TLR4, and CARD9 were moderately up-regulated in HaCaT within 6-h applications of both supernatants. HaCaT cells were more responsive to T1a than T XHB . The slight increase of dendritic cells-specific intercellular adhesion molecule 3-grabbing nonintegrin expression was faster and stronger, induced by T1a supernatant than T XHB . The moderate decreases of RNase 7, the slight up-regulations of Dectin-1 and interleukin-8 at the mRNA level were detected only in response to T1a rather than T XHB . After a long-time contact, all the elevated defense genes decreased after 24 h.

Conclusion: The culture supernatant of T. rubrum could directly and transiently activate the innate immune response of keratinocytes.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Line, Tumor
  • Culture Media, Conditioned / pharmacology*
  • Humans
  • Immunity, Innate / drug effects*
  • Keratinocytes / drug effects*
  • Keratinocytes / metabolism*
  • Trichophyton / metabolism*
  • beta-Glucans / metabolism

Substances

  • Culture Media, Conditioned
  • beta-Glucans