title: Association between serum zinc concentration and the Plasmodium falciparum antibody titer among rural villagers of Attapeu Province, Lao People's Democratic Republic.
abstract: Experimental studies have indicated that low serum zinc levels affect immune responses. However, few studies have evaluated the impact of serum zinc levels on antibody responses in the field in developing countries. We investigated an association between the anti-Plasmodium falciparum (Pf) antibody (immunoglobulin G) titer and serum zinc concentration among villagers in rural areas of the Lao People's Democratic Republic. Blood samples were collected to detect Pf infection. An enzyme-linked immunosorbent assay (ELISA) was used to measure the anti-PfIgG antibody titer. Each serum sample was assayed to measure the concentration of zinc. Pearson's correlation coefficient was applied to the association between zinc concentration and anti-PfIgG antibody titers. Multiple linear regression analysis was used to assess the association between zinc concentration and anti-PfIgG antibody titers, controlling for age and albumin level. Of 71 blood samples, 40 were Pf positive and 31 were Pf negative. The median serum zinc concentrations were 56.0 μg/dl in the Pf-positive group and 62.5 μg/dl in the Pf-negative group. The median anti-Pf titers were 833.4 in the positive group and 1237.2 in the negative group. Unexpectedly, there was a negative correlation between serum zinc and anti-Pf IgG antibody titers; the correlation coefficient were -0.453 and (p=0.003) in the positive group and -0.461 (p=0.009) in the negative group. The results of this study indicated sustained antibody responses among the villagers, who had likely been exposed to malaria periodically throughout their lives. Further studies are necessary to determine the conditions in which zinc could be effective against malaria.
authors: Center of Molecular Biosciences, Tropical Biosphere Research Center, University of the Ryukyus, 1 Senbaru, Nishihara-cho, Okinawa-ken 903-0213, Japan.
authors: Takeshi
authors: T
authors: Akiyama
authors: Tomoyo
authors: T
authors: Taniguchi
authors: Viengxay
authors: V
authors: Vanisaveth
authors: Yuba
authors: Y
authors: Inamine
authors: Nami
authors: N
authors: Toma
authors: Changchun
authors: C
authors: Li
authors: Hiromu
authors: H
authors: Toma
authors: Rie
authors: R
authors: Takeuchi
authors: Jun
authors: J
authors: Kobayashi
authors: Shigeyuki
authors: S
authors: Kano
authors: Bouasy
authors: B
authors: Hongvanthong
authors: Hisami
authors: H
authors: Watanabe
mesh_terms: D000293:Adolescent; D000328:Adult; D000913:Antibodies, Protozoan / Q000097:blood*; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D007812:Laos; D008297:Male; D008875:Middle Aged; D010963:Plasmodium falciparum / Q000276:immunology*; D012424:Rural Population; D044967:Serum / Q000737:chemistry* / Q000276:immunology*; D055815:Young Adult; D015032:Zinc / Q000097:blood*
chemical_list: D000913:Antibodies, Protozoan; D007074:Immunoglobulin G; D015032:Zinc