Ceravolo I P, Souza-Silva F A, Fontes C J F, Braga E M, Madureira A P, Krettli A U, Souza J M, Brito C F A, Adams J H, Carvalho L H
Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz (FIOCRUZ), Belo Horizonte, MG, Brazil.
Scand J Immunol. 2008 Mar;67(3):270-8. doi: 10.1111/j.1365-3083.2007.02059.x. Epub 2008 Jan 22.
The function of the Plasmodium vivax Duffy binding protein (DBP) during the erythrocyte invasion process is critical for successful parasite growth and pathogenesis in human infections. Although DBP is the subject of intensive malaria vaccine research, investigations on the functional proprieties of anti-DBP antibodies in the human population have been limited [Infect Immun68 (2000) 3164]. In the present study, we examined the ability of sera from different populations of the Brazilian Amazon--an area of markedly unstable malaria transmission--to inhibit the erythrocyte-binding function of the DBP ligand domain (region II, DBP(II)). We found that long-term exposure to malaria in the Amazon area elicits DBP-specific antibodies that inhibit the binding of different DBP(II) variants to erythrocytes. Despite the great variability of inhibitory antibody responses observed among study participants, we observed a positive correlation between erythrocyte binding-inhibitory activity and enzyme-linked immunosorbent assay anti-DBP antibodies. Of importance, there was a non-significant tendency towards increased levels of anti-DBP antibodies among individuals with asymptomatic P. vivax infections.
间日疟原虫达菲结合蛋白（DBP）在红细胞入侵过程中的功能对于人类感染中寄生虫的成功生长和发病机制至关重要。尽管DBP是疟疾疫苗深入研究的对象，但关于人群中抗DBP抗体功能特性的研究却很有限[《感染与免疫》68（2000）3164]。在本研究中，我们检测了来自巴西亚马逊地区不同人群（疟疾传播明显不稳定的地区）的血清抑制DBP配体结构域（区域II，DBP（II））红细胞结合功能的能力。我们发现，亚马逊地区长期接触疟疾会引发抑制不同DBP（II）变体与红细胞结合的DBP特异性抗体。尽管在研究参与者中观察到抑制性抗体反应存在很大差异，但我们观察到红细胞结合抑制活性与酶联免疫吸附测定抗DBP抗体之间呈正相关。重要的是，无症状间日疟感染个体中抗DBP抗体水平有升高的趋势，但差异不显著。
