Effect of treating Schistosoma haematobium infection on Plasmodium falciparum-specific antibody responses.
BACKGROUND
The overlapping geographical and socio-economic distribution of malaria and helminth infection has led to several studies investigating the immunological and pathological interactions of these parasites. This study focuses on the effect of treating schistosome infections on natural human immune responses directed against plasmodia merozoite surface proteins MSP-1 (DPKMWR, MSP1(19)), and MSP-2 (CH150 and Dd2) which are potential vaccine candidates as well as crude malaria (schizont) and schistosome (whole worm homogenate) proteins.


METHODS
IgG1 and IgG3 antibody responses directed against Schistosoma haematobium crude adult worm antigen (WWH) and Plasmodium falciparum antigens (merozoite surface proteins 1/2 and schizont extract), were measured by enzyme linked immunosorbent assay (ELISA) in 117 Zimbabweans (6-18 years old) exposed to S. haematobium and P. falciparum infection. These responses were measured before and after anti-helminth treatment with praziquantel to determine the effects of treatment on anti-plasmodial/schistosome responses.


RESULTS
There were no significant associations between antibody responses (IgG1/IgG3) directed against P. falciparum and schistosomes before treatment. Six weeks after schistosome treatment there were significant changes in levels of IgG1 directed against schistosome crude antigens, plasmodia crude antigens, MSP-1(19), MSP-2 (Dd2), and in IgG3 directed against MSP-1(19). However, only changes in anti-schistosome IgG1 were attributable to the anti-helminth treatment.


CONCLUSIONS
There was no association between anti-P. falciparum and S. haematobium antibody responses in this population and anti-helminth treatment affected only anti-schistosome responses and not responses against plasmodia crude antigens or MSP-1 and -2 vaccine candidates.
Reilly
L
L
Institute for Immunology and Infection Research, School of Biological Sciences, Ashworth Laboratories, University of Edinburgh, Edinburgh, UK. l.j.reilly@sms.ed.ac.uk
Magkrioti
C
C
Mduluza
T
T
Cavanagh
D R
DR
Mutapi
F
F
D000293:Adolescent; D000818:Animals; D000871:Anthelmintics / Q000627:therapeutic use; D000909:Antibodies, Helminth / Q000097:blood; D000913:Antibodies, Protozoan / Q000097:blood*; D000953:Antigens, Protozoan / Q000276:immunology; D002648:Child; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D016778:Malaria, Falciparum / Q000150:complications* / Q000276:immunology*; D020066:Merozoite Surface Protein 1 / Q000276:immunology; D010963:Plasmodium falciparum / Q000276:immunology*; D011223:Praziquantel / Q000627:therapeutic use; D015800:Protozoan Proteins / Q000276:immunology; D012553:Schistosomiasis haematobia / Q000150:complications* / Q000188:drug therapy* / Q000276:immunology
D000871:Anthelmintics; D000909:Antibodies, Helminth; D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D007074:Immunoglobulin G; D020066:Merozoite Surface Protein 1; D015800:Protozoan Proteins; C065974:merozoite surface protein 2, Plasmodium; D011223:Praziquantel