CD Markers

Home Chapter Home Jobs Conferences Fellowships Books

CD Markers

CD5

Reviewers: Nat Pernick, M.D., PathologyOutlines.com (see Reviewers page)
Revised: 24 December 2010, last major update December 2010
Copyright: (c) 2002-2010, PathologyOutlines.com, Inc.

General
=========================================================================

● Identifies B cells that produce antibodies using germ line (non mutated) configuration of gene segments, usually IgM

Terminology
=========================================================================

● Also known as T1

Physiology
=========================================================================

● Belongs to ancient scavenger receptor superfamily; at 11q13
● CD5+ B cells, which may arise from B-1 cells (subset of B cells) produce “generalist antibodies” using germline (nonmutation) configuration of gene segments - polyreactive low affinity "natural" antibodies (usually IgM) to exogenous antigens (tetanus toxoid, lipopolysaccharide) as well as autoreactive antibodies (Immunol Lett 1993;38:159)
● First line of defense against antigens; have a low activation threshold; are the only line of defense for those who cannot produce specific antibody
● Key regulator of immune tolerance; abnormalities may produce autoimmunity (Immunol Res 2002;26:255, Autoimmun Rev 2009;8:349)
● Binds to CD72

Clinical features
=========================================================================

● CD5 production is elevated in rheumatoid arthritis (represents 27-52% of circulating B cells vs. 20% normally)
● Polymorphism in CD5 promoter is associated with susceptibility to mantle cell lymphoma and CLL (Am J Clin Pathol 2005;123:646)

Uses
=========================================================================

● Marker for CLL, mantle cell lymphoma, T cells (normal and malignant), thymic carcinoma

Positive stains - normal
=========================================================================

● Thymocytes, almost all T cells, B cells of mantle zone of spleen and lymph nodes (12% of B cells in peripheral blood, Am J Clin Pathol 2004;121:368), B cells in peritoneal and pleural cavities
● In fetus, most B cells in spleen and cord blood are CD5 positive

Positive stains - disease
=========================================================================

● B cell CLL/SLL, mantle cell lymphoma (80-90%), diffuse large B cell lymphoma (10%-usually aggressive), aggressive variant of follicular lymphoma (rare, Am J Clin Pathol 2005;124:182), most T cell malignancies, NK/T cell lymphoma (variable), prolymphocytic leukemia, atypical thymoma (some), thymic carcinoma (almost all), CASTLE (thyroid tumor)
● Breast ductal carcinoma NOS stains with CD5 clone 4C7 (Arch Pathol Lab Med 2001;125:781)

Negative stains
=========================================================================

● Various T cell lymphomas: enteropathy associated, hepatosplenic alpha-beta and gamma-delta, large granular lymphocytic lymphoma; most B cell lymphomas other than mantle cell or CLL (although there rarely are CD5+ variant forms), Reed-Sternberg cells in Hodgkin’s lymphoma

Micro images
=========================================================================

Normal tonsil

Breast CLL/SLL - Contributed by Dr. Julia Braza, Beth Israel Deaconness Medical Center, Boston, Massachusetts (USA)

Left: cortical thymocytes and CD5; Right: medullary thymocytes and CD4

Thymic carcinoma (nonkeratinizing squamous cell subtype)

CASTLE tumor of thyroid

Flow cytometry images
=========================================================================

Mantle cell lymphoma with coexpression of CD5 and CD19

Additional references
=========================================================================

● MIM 153340

End of CD Markers > CD5

This information is intended for physicians and related personnel, who understand that medical information is often imperfect, and must be interpreted in the context of a patient's clinical data using reasonable medical judgment. This website should not be used as a substitute for the advice of a licensed physician.

All information on this website is protected by copyright of PathologyOutlines.com, Inc. Information from third parties may also be protected by copyright. Please contact us at copyrightPathOut@gmail.com with any questions (click here for other contact information).