Decay accelerating factor (DAF) as the host antigen with protective activity to complement killing of schistosomula

• Published in: Memórias do Instituto Oswaldo Cruz
• Main Author: F. Juarez Ramalho-Pinto
• Format: Article in Journal/Newspaper
• Language: English
• Published: Instituto Oswaldo Cruz, Ministério da Saúde 1987
• Subjects: Arctic medicine. Tropical medicine; RC955-962; Microbiology; QR1-502; Arctic
• Online Access: https://doi.org/10.1590/S0074-02761987000800037; https://doaj.org/article/e956252b00e240d1b557f22acab45d0b

The acquisition of host antigens by Schistosoma mansoni was studied by evaluating the resistance of schistosomula to the complement attack mediated by lethal antibody. Schistosomula cultured for 24 hours with intact human erythrocytes (N-HuE) or ghosts of any type of ABO or Rh blood group, showed a marked resistance to complement damage. Sheep red blood cells, pronase-treated N-HuE or erythrocytes from patients with paroxysmal nocturnal hemoglobinuria, which are complement-sensitive cells, were unable to protect schistosomula. Schistosomula protected by N-HuE became again susceptible to complement killing after incubation with a monoclonal antibody anti-DAF. These results indicate that, in vitro, host DAF from N-HuE can be acquired by schistosomula surface in a biological active form that protects the parasite from the complement lesion.