Crystal structure of Trichinella spiralis calreticulin and the structural basis of its complement evasion mechanism involving C1q.

ABSTRACT: Helminths produce calreticulin (CRT) to immunomodulate the host immune system as a survival strategy. However, the structure of helminth-derived CRT and the structural basis of the immune evasion process remains unclarified. Previous study found that the tissue-dwelling helminth Trichinella spiralis produces calreticulin (TsCRT), which binds C1q to inhibit activation of the complement classical pathway. Here, we used x-ray crystallography to resolve the structure of truncated TsCRT (TsCRT^Δ), the first structure of helminth-derived CRT. TsCRT^Δ was observed to share the same binding region on C1q with IgG based on the structure and molecular docking, which explains the inhibitory effect of TsCRT on C1q-IgG-initiated classical complement activation. Based on the k

SUBMITTER: Jia Z 

PROVIDER: S-EPMC11059001 | biostudies-literature | 2024

REPOSITORIES: biostudies-literature