Antigen-specific influence of GM/KM allotypes on IgG isotypes and association of GM allotypes with susceptibility to Plasmodium falciparum malaria.
BACKGROUND
Plasmodium falciparum malaria is a complex disease in which genetic and environmental factors influence susceptibility. IgG isotypes are in part genetically controlled, and GM/KM allotypes are believed to be involved in this control.


METHODS
In this study, 216 individuals from Daraweesh, an area of seasonal malaria transmission in Sudan, were followed for nine years for malaria infection. Total IgG and IgG isotypes against four malaria antigens, MSP2-3D7, MSP2-FC27, AMA1, and Pf332-C231 were measured in plasma obtained from the cohort at the end of the study, during the dry malaria-free period. The GM/KM allotypes of the donors were determined.


RESULTS
The GM 1,17 5,13,14,6 phenotype was associated with a higher incidence of malaria compared with the non-1,17 5,13,14,6 phenotypes (P = 0.037). Paradoxically, the carriers of the GM 1,17 5,13,14,6 phenotype had significantly higher baseline levels of total IgG and non-cytophilic IgG isotypes as compared to non-carriers. The KM allotypes influence on IgG isotypes level was limited. Finally, the differences in the baseline concentrations of total IgG and IgG isotypes between the different GK/KM phenotype carriers were antigen-dependent.


CONCLUSIONS
The results show that GM but not KM allotypes appeared to influence host susceptibility to uncomplicated malaria as well as the antibody profile of the donors, and the carriers of the GM 1,17 5,13,14,6 phenotype were the most susceptible


CONCLUSIONS
The GM allotypes have significant influence on susceptibility to uncomplicated P. falciparum malaria and antigen-dependent influence on total IgG and IgG subclasses.
Giha
Hayder A
HA
Department of Biochemistry, Faculty of Medicine and Medical Sciences, Arabian Gulf University (AGU), PO Box 26671, Manama, Kingdom of Bahrain. gehaha2002@yahoo.com
Nasr
Amre
A
Iriemenam
Nnaemeka C
NC
Arnot
David
D
Troye-Blomberg
Marita
M
Theander
Thor G
TG
Berzins
Klavs
K
ElGhazali
Gehad
G
Pandey
Janardan P
JP
D000293:Adolescent; D000328:Adult; D000818:Animals; D000913:Antibodies, Protozoan / Q000276:immunology*; D000953:Antigens, Protozoan / Q000276:immunology*; D002648:Child; D004198:Disease Susceptibility; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000145:classification / Q000276:immunology*; D007129:Immunoglobulin Gm Allotypes; D007131:Immunoglobulin Km Allotypes; D015994:Incidence; D016778:Malaria, Falciparum / Q000453:epidemiology / Q000276:immunology*; D008297:Male; D010963:Plasmodium falciparum / Q000276:immunology*; D013397:Sudan; D055815:Young Adult
D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D007074:Immunoglobulin G; D007129:Immunoglobulin Gm Allotypes; D007131:Immunoglobulin Km Allotypes