CD45 Isoform Expression in Microglia and Inflammatory Cells in HIV-1 Encephalitis

• Published in: Brain pathology (Zurich, Switzerland) Vol. 16; no. 4; pp. 256 - 265
• Main Authors: Cosenza-Nashat, Melissa A., Kim, Mee-Ohk, Zhao, Meng-Liang, Suh, Hyeon-Sook, Lee, Sunhee C.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.10.2006
• Subjects: AIDS Dementia Complex - etiology; AIDS Dementia Complex - immunology; AIDS Dementia Complex - metabolism; Brain - immunology; Brain - pathology; HIV-1 - immunology; HIV-1 - metabolism; Human immunodeficiency virus 1; Humans; Immunohistochemistry; Leukocyte Common Antigens - biosynthesis; Lymphocytes - immunology; Lymphocytes - metabolism; Macrophages - immunology; Macrophages - metabolism; Microglia - metabolism; Middle Aged; Protein Isoforms - biosynthesis
• ISSN: 1015-6305; 1750-3639
• DOI: 10.1111/j.1750-3639.2006.00027.x

CD45 is a membrane tyrosine phosphatase that modulates the function of the hematopoietic cells. In vitro, agonist antibodies to CD45RO or CD45RB isoforms have been shown to suppress microglial activation, but whether microglia in vivo express these isoforms in HIV encephalitis (HIVE) is unknown. Brain sections from control and HIVE were immunostained for CD45 isoforms using exon‐specific antibodies (RA, RB, RC and RO). RA and RC were limited to rare lymphocytes, while RB expression was robust in microglia and inflammatory cells. RO was low in control microglia, but increased in HIVE. RO was also localized to macrophages and CD8+ T cells. Targeting CD45 in vivo with isoform‐specific antibodies remains a therapeutic option for neuroinflammatory diseases.