In vitro immunoregulatory role of recombinant Ancylostoma ceylanicum calreticulin

Abstract

<i>Ancylostoma ceylanicum</i> is a zoonotic soil-derived nematode that parasitizes the intestines of humans and animals (dogs and cats), leading to malnutrition and iron-deficiency anemia. Helminth parasites secrete calreticulin (CRT), which regulates or blocks the host’s immune response. However, no data on <i>A. ceylanicum</i> calreticulin (<i>Ace</i>-CRT) are available. We investigated the biological function of recombinant <i>Ace</i>-CRT (<i>rAce</i>-CRT). rAce-CRT showed reliable antigenicity and stimulated the proliferation of mouse splenocytes and canine peripheral blood mononuclear cells. Quantitative reverse-transcription PCR assays revealed that r<i>Ace</i>-CRT primarily promoted the expression of T helper 2 cytokines, particularly IL-13, in canine peripheral blood lymphocytes. r<i>Ace</i>-CRT inhibited complement-mediated sheep erythrocyte hemolysis in vitro. Our findings indicate that <i>Ace</i>-CRT plays an immunomodulatory role and may be a promising candidate molecule for a hookworm vaccine.