Department of Histopathology, Surgical and Medical Sciences, Queen's Medical Centre, Nottingham University Hospitals Trust, Nottingham NG7 2UH, United Kingdom.
J Allergy Clin Immunol. 2010 Jan;125(1):139-45.e1-3. doi: 10.1016/j.jaci.2009.07.025. Epub 2009 Oct 8.
Allergic rhinitis is characterized by mast cell degranulation induced by antigen cross-linking of IgE. It has been proposed that some patients with rhinitis show nasal allergy in the absence of systemic markers of atopy, termed entopy. Recent murine studies suggest the existence of an IgE-independent hypersensitivity response involving antigen-induced mast cell activation, mediated by immunoglobulin free light chains (FLCs).
To determine whether FLC is associated with mast cell-mediated nasal hypersensitivity and its relationship with eosinophilic activity in allergic and nonatopic rhinitis.
Patients with allergy and nonallergic rhinitis with eosinophilia syndrome (NARES) had levels of soluble FLC measured in nasal secretions and serum. In addition, levels of the nasal inflammatory mediators mast cell tryptase and eosinophil cationic protein were quantified. Cellular expression of kappa and lambda FLC was characterized in the nasal mucosa of allergic and nonatopic idiopathic rhinitis and control subjects by using immunohistochemistry. Immunopositive cells were phenotyped by using laser microdissection and PCR.
Free light chain was significantly increased in nasal secretions of subjects with allergy and NARES, and in serum of patients with NARES. Nonatopic patients with allergy showed significantly increased nasal mast cell tryptase and eosinophil cationic protein. FLC-positive cells were significantly increased in allergic and nonatopic mucosa, and were shown to be mast cells and plasma cells.
Nasal FLC is significantly increased in allergic and nonatopic rhinitis nasal mucosa, suggesting a role in nasal hypersensitivity. Further studies are needed to identify which allergens trigger FLC-mediated responses in nonatopic rhinitis.
变应性鼻炎的特征是 IgE 交联诱导的肥大细胞脱颗粒。有人提出，一些鼻炎患者在没有过敏全身标志物的情况下表现出鼻过敏，称为 entopy。最近的鼠类研究表明，存在一种 IgE 非依赖性过敏反应，涉及抗原诱导的肥大细胞激活，由免疫球蛋白游离轻链（FLC）介导。
确定 FLC 是否与肥大细胞介导的鼻过敏有关，以及其与变应性和非变应性鼻炎中嗜酸性粒细胞活性的关系。
测量变应性和非变应性鼻炎伴嗜酸性粒细胞增多综合征（NARES）患者鼻腔分泌物和血清中的可溶性 FLC 水平。此外，还定量了鼻腔炎症介质肥大细胞胰蛋白酶和嗜酸性粒细胞阳离子蛋白的水平。通过免疫组织化学，在变应性和非变应性特发性鼻炎和对照受试者的鼻黏膜中，对 κ 和 λ FLC 的细胞表达进行了特征描述。通过激光微切割和 PCR 对免疫阳性细胞进行表型鉴定。
过敏和 NARES 患者的鼻腔分泌物以及 NARES 患者的血清中 FLC 明显增加。过敏的非变应性患者的鼻腔肥大细胞胰蛋白酶和嗜酸性粒细胞阳离子蛋白明显增加。FLC 阳性细胞在变应性和非变应性黏膜中明显增加，并被证明是肥大细胞和浆细胞。
变应性和非变应性鼻炎鼻黏膜中 FLC 明显增加，提示其在鼻过敏中的作用。需要进一步研究以确定哪些过敏原会引发非变应性鼻炎中 FLC 介导的反应。
