Department of Veterinary Anatomy, College of Bioresource Sciences, Nihon University, Kanagawa.
Eur J Histochem. 2021 Nov 2;65(4):3320. doi: 10.4081/ejh.2021.3320.
In the present study, the expression of secretory components and vesicular transport proteins in the canine lacrimal gland was examined and morphometric analysis was performed. The secretory epithelium consists of two types of secretory cells with different morphological features. The secretory cells constituting acinar units (type A cells) exhibited higher levels of glycoconjugates, including β-GlcNAc, than the other cell type constituting tubular units (type T cells). Immunoblot analysis revealed that antimicrobial proteins, such as lysozyme, lactoferrin and lactoperoxidase, Rab proteins (Rab3d, Rab27a and Rab27b) and soluble N-ethylmaleimide-sensitive fusion protein attachment protein receptor (SNARE) proteins (VAMP2, VAMP4, VAMP8, syntaxin-1, syntaxin-4 and syntaxin-6), were expressed at various levels. We immunohistochemically demonstrated that the expression patterns of lysozyme, lactoferrin, Raba27a, Rab27b, VAMP4, VAMP8 and syntaxin-6 differed depending on the secretory cell type. Additionally, in type T cells, VAMP4 was confined to a subpopulation of secretory granules, while VAMP8 was detected in almost all of them. The present study displayed the morphological and histochemical characteristics of the secretory epithelium in the canine lacrimal gland. These findings will help elucidate the species-specific properties of this gland.
在本研究中，我们研究了犬泪腺中分泌成分和囊泡转运蛋白的表达，并进行了形态计量分析。分泌上皮由两种具有不同形态特征的分泌细胞组成。构成腺泡单位的分泌细胞（A 细胞）比构成管状单位的其他细胞（T 细胞）具有更高水平的糖缀合物，包括β-GlcNAc。免疫印迹分析显示，抗菌蛋白，如溶菌酶、乳铁蛋白和乳过氧化物酶、Rab 蛋白（Rab3d、Rab27a 和 Rab27b）和可溶性 N-乙基马来酰亚胺敏感融合蛋白附着蛋白受体（SNARE）蛋白（VAMP2、VAMP4、VAMP8、突触素-1、突触素-4 和突触素-6）以不同水平表达。我们通过免疫组织化学方法证明，溶菌酶、乳铁蛋白、Rab27a、Rab27b、VAMP4、VAMP8 和突触素-6 的表达模式取决于分泌细胞类型。此外，在 T 细胞中，VAMP4 局限于分泌颗粒的亚群，而 VAMP8 则几乎存在于所有分泌颗粒中。本研究显示了犬泪腺分泌上皮的形态和组织化学特征。这些发现将有助于阐明该腺体的种特异性特性。
