Pathology Outlines

CD Markers
CD45RB

Topic Completed: 1 October 2013

Revised: 13 August 2019

Revised: 14 December 2018, last major update October 2013

Copyright: (c) 2003-2015, PathologyOutlines.com, Inc.

PubMed Search: CD45RB[title]

Related topics: CD45, CD45RO, CD45RA, CD45RC

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Page views in 2020 to date: 171

Table of Contents

Cite this page: Pernick N. CD45RB. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/cdmarkerscd45rb.html. Accessed February 27th, 2020.

Definition / general

CD45 isoform generated by alternative mRNA splicing of exon 5, leading to change in the extracellular domain of the molecule (J Exp Med 1987;166:1548)
Influx of CD4+, CD45RB high T cells is present in inflammatory bowel disease; may be important in pathogenesis as they produce more proinflammatory cytokines than CD4+ CD45RB low T cells (J Leukoc Biol 2004;75:1010)

Diagrams / tables

CD45RB expression changes during germinal center reaction

Pathophysiology

CD45 is a high molecular weight transmembrane protein with intrinsic tyrosine phosphatase activity
CD45 is heavily glycosylated, and expressed at high levels on nucleated hematopoietic cells
CD45 isoforms, including CD45RB, are generated by alternative mRNA splicing of exons 4 (CD45RA), 5 (CD45RB) and 6 (CD45RC), leading to changes in the extracellular domain of the molecule
Down regulated in memory cells

Uses by pathologists

No significant clinical use by pathologists

Positive staining - normal

Similar staining as CD45, except not expressed in Langerhans cells and some T cells
B cells, most T cells, monocytes, macrophages and granulocytes (weak)

Positive staining - disease

Most leukemias and lymphomas

Negative staining

Some T cells; Langerhans cells, platelets
Plasma cell neoplasms, Reed-Sternberg cells, some lymphoblastic lymphomas and some anaplastic large cell lymphomas