MedLec, a C-type lectin receptor, has crucial role in response to systemic A. fumigatus infection

Submitted by ROrritt on 23 April 2018

The C-type lectins, a family of pattern recognition receptors responsible for recognizing microbes, are key players in antifungal immunity. C-type lectins start a chain reaction in the immune system following identification of fungal species.

A letter published in the journal Nature has described a C-type lectin receptor that recognises fungal melanin, aptly named the melanin-sensing C-type lectin receptor (MelLec). This receptor recognises melanin in conidial spores of Aspergillus fumigatus, and in any other type of fungi that have 1,8-dihydrocynaphthalene (DHN)-melanin.

The authors of this letter have found that MedLec is expressed by endothelial cells in mice, and was required for appropriate immune response to disseminated A. fumigatus infection. They also found that MedLec is expressed by both epithelial and myeloid cells in humans, and identified a single nucleotide polymorphism that inhibited myeloid inflammatory responses and increased the susceptibility of stem-cell transplant recipients to disseminated Aspergillus infection.

The letter speculates that screening for the less effective single nucleotide polymorphism in stem-cell donors could help to reduce the incidence of disseminated aspergillosis in stem-cell transplant recipients.