IgE response in schistosomiasis japonica: characterization of a cercarial allergen in comparison with purified egg allergens.
The relationship between the cercarial allergen and two previously isolated egg allergens (J1, J2) of Schistosoma japonicum was examined especially in terms of the cross-reactivity between them. Semi-purified cercarial allergen (JAC) was obtained from the crude extract of S. japonicum cercariae by gel chromatography on Sephadex G-200. The apparent molecular weight of JAC was estimated approximately as 60-100 kDa. JAC could bind to Con A-Sepharose, indicating its glycoprotein nature. Three groups of BALB/c mice were immunized with JAC , J1 or J2 using A1(OH)3 as adjuvant, and the cross-reactivity of each anti-serum was examined by PCA. Anti-JAC, anti-J1 or anti-J2 serum was highly specific to the corresponding antigen. When IgE-ELISA of S. japonicum patient sera was performed using JAC, J1 or J2 as an antigen, the correlation between anti-J1 and anti-J2 (r = 0.78) was high, whereas the correlation between anti-JAC and anti-J1 (r = 0.27) or between anti-JAC and anti-J2 (r = 0.12) was low. These results suggest that most IgE epitopes on cercarial allergen are independent from those on egg allergens in S. japonicum.
Owhashi
M
M
Faculty of Integrated Arts and Sciences, The University of Tokushima, Minami-Johsanjima, Tokushima 770, Japan.
Horii
Y
Y
Ishii
A
A
D000818:Animals; D000947:Antigens, Helminth / Q000032:analysis*; D003429:Cross Reactions; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes; D005260:Female; D007073:Immunoglobulin E / Q000096:biosynthesis*; D051379:Mice; D008807:Mice, Inbred BALB C; D010063:Ovum / Q000276:immunology; D012552:Schistosomiasis / Q000276:immunology*; D012554:Schistosomiasis japonica / Q000276:immunology*; D012680:Sensitivity and Specificity
D000947:Antigens, Helminth; D000939:Epitopes; D007073:Immunoglobulin E