CD44 Expression in Microglia of the Retina and Cerebellum of Developing and Adult Chicken.
10.11637/kjpa.2017.30.1.29
- Author:
Ji Young KIM
1
;
Hyun Joon SOHN
;
Je Hoon SEO
;
Eun Young LEE
Author Information
1. Department of Anatomy, College of Medicine, Chungbuk National University, Korea. eylee@chungbuk.ac.kr seojh@chungbuk.ac.kr
- Publication Type:Original Article
- Keywords:
CD44;
Microglia;
Chicken;
Retina;
Cerebellum
- MeSH:
Adult*;
Cell Body;
Cerebellar Cortex;
Cerebellum*;
Chickens*;
Cytoplasm;
Embryonic Structures;
Humans;
Hyaluronic Acid;
Microglia*;
Nerve Fibers;
Retina*
- From:Korean Journal of Physical Anthropology
2017;30(1):29-38
- CountryRepublic of Korea
- Language:English
-
Abstract:
CD44 is a transmembrane protein that acts as a receptor for an adhesion molecule, hyaluronic acid. The type of cells expressing CD44 and roles of CD44 are still controversial and need to be elucidated. The aim of the present study was to examine the type of cells expressing CD44 and the changes in their distribution in the retina and the cerebellum of the developing and adult chicken. Embryonic day 14 (E14) and post-hatch day 90 (P90) chickens were used in this study. CD44-immunoreactive (ir) cells were observed both in the retina and the cerebellum of the two developmental stages examined. In the retina of E14, CD44-ir cells were mainly located in the nerve fiber layer. In adults, most of the CD44-ir cells were in the nerve fiber layer and some were dispersed in other layers of the retina. In the cerebellum of E14, CD44-ir cells were distributed throughout the cerebellar cortex, including the external and internal granular layers. CD44-ir cells were more frequently found in the cerebellum of P90 adult chickens than in that of E14 embryos. At higher magnification, CD44-ir cells showed ramified cytoplasmic processes irradiating from their cell bodies. In the retina and in the cerebellum of all ages examined, double staining showed that most of the CD44-ir cells also expressed RCA-1, a marker of microglia. In contrast to that, at the same locations, GFAP and CD44 were not co-expressed in cells. When the adult retina was stimulated by LPS, CD44 immunoreactivity increased, and CD44-ir cells were also RCA-1-positive. The present results indicated that CD44 was expressed in microglia of the retina and the cerebellum of the developing and adult chicken even in normal conditions, and microglial CD44 expression was increased upon LPS stimulation.
