title: Antibody isotype responses, infection and re-infection for Schistosoma japonicum in a marshland area of China.
abstract: Antibody isotype responses to adult worm antigen (AWA) of Schistosoma japonicum and two recombinant proteins (paramyosin (PMY) and a 22 kDa tegumental membrane-associated antigen (TEG)) were analyzed in 137 individuals from an area moderately endemic for schistosomiasis in the Dongting Lake region, Hunan Province, China. The prevalence and geometric mean (GM) intensity of infection before the implementation of curative chemotherapy were 28.5% and 234.4 epg, respectively, but 9 months after treatment the prevalence (6.6%) and intensity (38.3 epg) had decreased. There was no significant difference in either the prevalence or intensity of infection between males and females. Specific IgG (total), IgG4, IgG2, IgA and IgE responses to AWA, PMY and TEG were measured by ELISA. Males produced significantly (P < 0.05) more anti-AWA total IgG, IgE, IgA, IgG4 and IgG2 antibodies, and anti-TEG IgG2 antibody than their female counterparts. The OD450 levels of anti-AWA, PMY and TEG antibody isotypes did not present clear age-dependent trends except for peak levels of anti-AWA IgG4 antibodies evident among subjects 20-29 years of age. The total IgG and IgG4 antibody profiles against AWA correlated well with current S. japonicum infections while anti-AWA IgG2, IgA and IgE antibodies did not show such an association. Anti-AWA-specific IgE antibody levels were positively correlated (r = 0.55) with anti-AWA specific IgG4 antibody levels. In addition, the overall percentage of responders (using a cut-off value obtained from normal controls) to all isotypes to AWA were higher than those observed for both the recombinant antigens. Only 18.2%, 16.8% and 7.3% of the study population were IgE responders to AWA, PMY and TEG. A longer follow-up period is required before we can more fully understand the role of IgE, if any, in protective immunity against schistosomiasis japonica.
authors.affiliation: Australian Centre for International and Tropical Health and Nutrition, The University of Queensland and the Queensland Institute of Medical Research, Brisbane. yueshenl@qimr.edu.au
authors.forename: Y S
authors.initials: YS
authors.lastname: Li
authors.forename: A G
authors.initials: AG
authors.lastname: Ross
authors.forename: A C
authors.initials: AC
authors.lastname: Sleigh
authors.forename: Y
authors.initials: Y
authors.lastname: Li
authors.forename: G J
authors.initials: GJ
authors.lastname: Waine
authors.forename: G J
authors.initials: GJ
authors.lastname: Williams
authors.forename: M
authors.initials: M
authors.lastname: Tanner
authors.forename: D P
authors.initials: DP
authors.lastname: McManus
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood*; D000947:Antigens, Helminth / Q000276:immunology; D002648:Child; D002681:China / Q000453:epidemiology; D015331:Cohort Studies; D019353:Endemic Diseases; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005618:Fresh Water; D015801:Helminth Proteins; D006801:Humans; D007132:Immunoglobulin Isotypes / Q000097:blood*; D008297:Male; D008562:Membrane Glycoproteins / Q000276:immunology; D008875:Middle Aged; D011223:Praziquantel / Q000627:therapeutic use; D015995:Prevalence; D012008:Recurrence; D012424:Rural Population; D012554:Schistosomiasis japonica / Q000188:drug therapy / Q000453:epidemiology* / Q000276:immunology*; D012737:Sex Factors; D014335:Tropomyosin / Q000276:immunology
chemical_list: D000909:Antibodies, Helminth; D000947:Antigens, Helminth; D015801:Helminth Proteins; D007132:Immunoglobulin Isotypes; D008562:Membrane Glycoproteins; D014335:Tropomyosin; C072491:membrane glycoprotein antigen GP22, Schistosoma; D011223:Praziquantel