背景:克罗恩病(CD)的病因尚不清楚。最近已经报道了CD患者外周血中全球淋巴细胞群体的减少。这种减少在γδT淋巴细胞中更为明显,特别是γδCD8+T亚群。此外,在这些患者中也观察到IL-7的降低.我们提出了一个假设,即微孢子虫,一种最近与真菌有关的专性细胞内机会性寄生虫,在CD患者中,可以利用淋巴细胞和IL-7缺陷进行增殖,并有助于这种疾病的病理生理。
结果:在本病例对照研究中,从36名CD患者和36名健康个体(对照)收集血清样本,用ELISA法测定IgE和IgG抗头孢菌素抗体;通过实时聚合酶链反应(PCR)分析44例肠组织样本,二十名CD患者,9名与其他疾病和15名健康受试者。我们观察到CD患者的IgE抗头孢菌素水平明显高于对照组:0.386(±0.256),0.201(±0.147),P<0.001。然而,CD患者的IgG抗头孢菌素值显着降低:0.361(±0.256)与对照组相比,0.876(±0.380),P<0.001。在CD患者组中,6/20(30%)的微孢子虫实时PCR阳性,对照组患者实时荧光定量PCR均为阴性。
结论:这些结果表明,CD患者是微孢子虫病的高危人群,此外,微孢子虫可能是CD的病因。
BACKGROUND: The cause of Crohn\'s Disease (CD) remains unknown. Recently a decrease in the global lymphocyte population in the peripheral blood of CD patients has been reported. This decrease was more evident in γδ T lymphocytes, especially γδ CD8+T subsets. Furthermore, a decrease of IL-7 was also observed in these patients. We propose the hypothesis that microsporidia, an obligate intracellular opportunistic parasite recently related to fungi, in CD patients can take advantage of the lymphocytes and IL-7 deficits to proliferate and to contribute to the pathophysiology of this disease.
RESULTS: In this case-control
study, serum samples were collected from 36 CD patients and from 36 healthy individuals (controls), IgE and IgG anti-
Encephalitozoon antibodies were determined by ELISA; and forty-four intestinal tissue samples were analyzed through real time Polymerase Chain Reaction (PCR), twenty CD patients, nine with others diseases and 15 healthy subjects. We observed that IgE anti-
Encephalitozoon levels were significantly higher in patients with CD: 0.386(±0.256) vs control group, 0.201(±0.147), P<0.001. However, IgG anti-
Encephalitozoon values were significantly lower in CD patients: 0.361(±0.256) vs control group, 0.876(±0.380), P<0.001. In the group of CD patients, 6/20 (30%) were positive by real time PCR for microsporidia and, all the patients of the control group were negative by real time PCR.
CONCLUSIONS: These results suggest that CD patients are a group at risk for microsporidiasis and, moreover that microsporidia may be involved as a possible etiologic factor of CD.