IMMUNOGLOBULIN-G (IGG) SUBCLASS AND IGE RESPONSES IN HUMAN PARAGONIMIASES CAUSED BY 3 DIFFERENT SPECIES

In 40 cases of human paragonimiases caused by Paragonimus,westermani ( 20 cases), P. miyazakii (10 cases), and P. skrjabini (10 cases), respo nses of serum immunoglobulin G (IgG), IgG subclasses, and IgE were ana lyzed by immunoblotting with crude antigens prepared from egg, 4-week old juvenile, and adult forms of P. westermani. The 32- and 35-kDa pro teins in the adult extracts showed specific reactions regardless of th e causative species (39 of 40 cases; 98%). Sera of patients infected w ith P. westermani and P. miyazakii reacted strongly with the 28-, 46-, and 94-kDa proteins of egg extracts, while those from patients infect ed with P. skrjabini reacted faintly. No sera from patients with other trematodiases (0 of 15 cases), cestodiases (0 of 20 cases), or lung c ancer (0 of 5 cases) or from healthy controls (0 of 10 individuals) sh owed positive reactions. Analysis by IgG subclass revealed that IgG4 ( 33 of 40 cases; 83%) and IgG1 (29 of 40 cases; 73%) antibodies in the patient sera recognized the 32- and 35-kDa proteins predominantly. IgG 3 reaction was found in 50% (10 of 20 cases) and 30% (3 of 10 cases) o f the sera of patients infected with P. westermani and P. miyazakii, r espectively. In an IgE immunoblot, 83% (33 of 40 cases) of the sera fr om paragonimiasis patients reacted with the 32- and 35-kDa proteins wh ile no sera from patients with heterologous diseases and healthy contr ols showed a positive reaction. Both 32- and 35-kDa proteins in adult extracts of P. westermani were highly reliable for serodiagnosis of hu man paragonimiases.