Bereczky Sándor, Montgomery Scott M, Troye-Blomberg Marita, Rooth Ingegerd, Shaw Marie-Anne, Färnert Anna
Infectious Diseases Unit, Karolinska University Hospital, Karolinska Institutet, S-171 76 Stockholm, Sweden.
Int J Parasitol. 2004 Jul;34(8):935-42. doi: 10.1016/j.ijpara.2004.04.007.
Immunological characteristics were assessed for prospective risk of clinical malaria in a longitudinally followed population in a holoendemic area of Tanzania. Baseline characteristics including crude Plasmodium falciparum extract-specific IgE and IgG; total IgE; and parasitological indices, e.g. number of P. falciparum clones, were investigated among 700 asymptomatic individuals. Cox regression analysis estimated the risk of succumbing to a new clinical episode during a 40 weeks follow up. High anti-P. falciparum IgE levels were associated with reduced risk of acute malaria in all age groups independently of total IgE levels. Statistically significant reduced odds ratio of 0.26 (95% CI, 0.09-0.72, P=0.010) and 0.44 (95% CI, 0.19-0.99, P=0.047) for the two highest fifths, respectively was observed after adjustment for age, sex, total IgE, numbers of parasite clones per infection and HIV-1 seropositivity. In contrast, high levels of malaria specific IgG or total IgE were not associated with reduced risk to succumb to a new clinical episode. A protective effect of asymptomatic multiclonal P. falciparum infections was also confirmed. For the first time, anti-malarial IgE levels in asymptomatic individuals in endemic area are found to be associated with reduced risk for subsequent malaria disease. Specific IgE antibodies may play role in maintaining anti-malarial immunity, or indicate other aspects of immune function relevant for protection against malaria.
在坦桑尼亚一个疟疾高度流行地区，对纵向随访人群临床疟疾的潜在风险进行了免疫特征评估。在700名无症状个体中调查了基线特征，包括恶性疟原虫提取物特异性IgE和IgG、总IgE以及寄生虫学指标，如恶性疟原虫克隆数。Cox回归分析估计了在40周随访期间发生新临床发作的风险。无论总IgE水平如何，所有年龄组中高抗恶性疟原虫IgE水平均与急性疟疾风险降低相关。在对年龄、性别、总IgE、每次感染的寄生虫克隆数和HIV-1血清阳性进行调整后，分别观察到两个最高五分位数的优势比显著降低，分别为0.26（95%CI，0.09 - 0.72，P = 0.010）和0.44（95%CI，0.19 - 0.99，P = 0.047）。相比之下，高水平的疟疾特异性IgG或总IgE与发生新临床发作的风险降低无关。无症状多克隆恶性疟原虫感染的保护作用也得到了证实。首次发现流行地区无症状个体的抗疟疾IgE水平与随后患疟疾疾病的风险降低相关。特异性IgE抗体可能在维持抗疟疾免疫中发挥作用，或表明免疫功能与预防疟疾相关的其他方面。
