IMAGING OCULAR IMMUNE RESPONSES BY INTRAVITAL MICROSCOPY

The eye offers excellent opportunities to observe cellular interactions in vivo. This applies especially to the immune response in which discrete events can be studied, including cell trafficking, transendothelial migration, adhesion, antigen presentation, and T cell activation. Intravital microscopy has allowed study of immune cell interactions in tissues such as the conjunctiva, the inflamed cornea, and the iris. Thus the real-time observation of presentation of antigen injected into the anterior chamber of the eye can be imaged using fluorescently labelled antigen and cells. Application of the scanning laser ophthalmoscope to the rat and mouse eye allows analysis of leukocyte-endothelial interactions in the retinal and choroidal circulations. These studies have provided important information on rolling and adhesion of leukocytes in real time in different microvascular beds that have not been manipulated in any way and has, for instance, provided quantitation to the effects of shear stress on leukocyte-endothelial adhesion. In addition, the model permits an accurate analysis of the timing of trafficking of T cells into the eye and the possibility of determining which cells, if any, may be responsible for antigen presentation in the tissues as opposed to the secondary lymphoid organs. Finally, these experimental methods are now being applied to the human eye and should prove valuable in determining the nature of tissue damage events in the eye as well as evaluating the response to treatments.     

肾髓质间质细胞扫描电镜观察

用盐酸—吐温法除去结缔组织细胞间质后,在扫描电镜下观察了大鼠肾髓质间质细胞。依细胞外形,肾髓质间质细胞可分为有突起的和无突起的两类;有突起的又可分为杆状胞体和球状胞体两种。杆状有突起的间质细胞最多,横行连接在血管和肾小管之间,细胞突起在血管壁和肾小管壁上形成致密网,有的突起末端膨大为球盘状,附着于血管壁。球状有突起间质细胞数量较少,散在于髓质,其突起细小,附着于邻近的血管或肾小管壁上。无突起细胞数量亦少,附着于杆状有突起间质细胞的胞体上。本文并扼要讨论了它们的功能意义。