Role of calreticulin from parasites in its interaction with vertebrate hosts.
Although parasites range from protozoan to complex, evolutionary advanced arthropods, in general, a hallmark of parasite life cycles is their ability to adapt to changes in temperature, pH and host defense strategies. Calreticulin, a calcium-binding protein, highly conserved and multifunctional, is present in every cell of higher organisms, except erythrocytes. The surprising array of calreticulin-associated functions include lectin-like chaperoning, calcium storage and signaling, modulation of gene expression, cell adhesion, enhancement of phagocytosis of C1q or collectin opsonized apoptotic cells, inhibition of angiogenesis and tumoral growth, inhibition of perforin pore formation in T and NK cells, and inhibition of C1q-dependent complement activation. Likewise, calreticulin is present in a wide spectrum of sub cellular compartments. Parasite calreticulin shows a surprisingly high degree of conservation within the framework of its functional domains. Its role within the parasite/host relationship needs to be assessed further, in particular with regard to its impact on parasite infectivity, by helping to evade from its hosts' immune response. With special emphasis on calreticulin from Trypanosoma cruzi, the intracellular protozoan agent of American trypanosomiasis (Chagas' disease), we wish to exemplify and highlight the various implications of parasite calreticulin, within the pathophysiology of parasite-mediated human and animal disease.
Ferreira
Viviana
V
Programa de Immunología, ICBM, Facultad de Medicina, Universidad de Chile, Santiago, Chile.
Molina
María Carmen
MC
Valck
Carolina
C
Rojas
Alvaro
A
Aguilar
Lorena
L
Ramírez
Galia
G
Schwaeble
Wilhelm
W
Ferreira
Arturo
A
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D037282:Calreticulin / Q000235:genetics / Q000378:metabolism*; D014355:Chagas Disease / Q000378:metabolism*; D003165:Complement System Proteins / Q000378:metabolism; D006790:Host-Parasite Interactions / Q000502:physiology; D006801:Humans; D018832:Molecular Chaperones / Q000378:metabolism; D014349:Trypanosoma cruzi / Q000378:metabolism*; D014714:Vertebrates / Q000469:parasitology
D037282:Calreticulin; D018832:Molecular Chaperones; D003165:Complement System Proteins; D002118:Calcium