• gp110
• macrosialin

MAJOR LINKS FOR CD68  

• NCBI LocusLink Record: 968
• Mendelian Inheritance in Man (OMIM): 153634
• SwissProt annotated protein record: P34810

CELLULAR FUNCTION OF CD68   - Unknown at this time

DISEASE RELEVANCE OF CD68 AND FUNCTION OF CD68 IN INTACT ANIMAL   - No information

• Families in which CD68 is a member
  • CD68-->distinguishing features of dermal dendritic cells and Langerhans cells
  • CD68-->sialomucin-->Mucins
  • CD68-->lamp
  • CD68-->SR-D class-->host defense scavenger receptors-->scavenger receptor superfamily

MOLECULAR STRUCTURE OF CD68  

• A 110 kDa transmembrane (Type I) glycoprotein consisting of a polypeptide of
• 35367 kDa (354 amino acids) predicted from the cDNA sequence
• 9 potential N-linked glycosylation sites
• The extra-cellular region consists of 298 residues with two domains connected by a proline-rich hinge
• The N-terminal region represents a mucin-like domain comprised of short peptide repeats and highly enriched serine and threonine residues, which may bear O-linked glycan chains
• The domain close to the membrane shows homology to a family of lysosomal/plasma membrane shuttling proteins (LGP) which include lamp 1 and lamp 2

MOLECULAR MASS OF CD68  

POST-TRANSCRIPTIONAL MODIFICATION OF CD68   - No information

POST-TRANSLATIONAL MODIFICATION OF CD68   - Highly glycosylated

SUBSTRATES FOR CD68   - No information

ENZYMES WHICH MODIFY CD68   - No information

LIGANDS FOR CD68 AND MOLECULES ASSOCIATED WITH CD68  

• Expressed intracellularly in cytoplasmic granules but can be detected in smaller amounts on the surface of cells
• Monocytes and macrophages
• Dendritic cells**
• Neutrophils
• Basophils
• Mast cells**
• Myeloid progenitor cells**
• Subset of CD34+ hemopoietic bone marrow progenitor cells**
• Activated T cells**
• Expressed by approximately 40% of peripheral blood B-lymphocytes and 50% of all B-ALL stain weakly for CD68
• Found in cytoplasm of non-hemopoietic tissues, especially in the liver, glomeruli, and renal tubules
• Soluble forms have been found in serum and urine

SELECTION OF OTHER CD68-SPECIFIC REFERENCE MAB  

REVIEWS

PRIMARY CITATIONS

1. Cordell JL, Falini B, Flenghi L, Jones DB, Pileri S, Radzun HJ, and WilkinsBS. Leukocyte Typing V 925-927

2. Davey FR,Cordell JL,Erber WN,Pulford KA,Gatter KC,Mason DY Monoclonal antibody (Y1/82A) with specificity towards peripheral blood monocytes and tissue macrophages. J Clin Pathol 1988 41:753 PubMed

3. Fukuda M Lysosomal membrane glycoproteins. Structure, biosynthesis, and intracellular trafficking. J Biol Chem 1991 266:21327 PubMed

4. Holness CL,Simmons DL Molecular cloning of CD68, a human macrophage marker related to lysosomal glycoproteins. Blood 1993 81:1607 PubMed

5. Pulford KA,Rigney EM,Micklem KJ,Jones M,Stross WP,Gatter KC,Mason DY KP1: a new monoclonal antibody that detects a monocyte/macrophage associated antigen in routinely processed tissue sections. J Clin Pathol 1989 42:414 PubMed

6. Pulford KA,Sipos A,Cordell JL,Stross WP,Mason DY Distribution of the CD68 macrophage/myeloid associated antigen. Int Immunol 1990 2:973 PubMed

7. Rabinowitz SS,Gordon S Macrosialin, a macrophage-restricted membrane sialoprotein differentially glycosylated in response to inflammatory stimuli. J Exp Med 1991 174:827 PubMed

8. Ramprasad MP,Fischer W,Witztum JL,Sambrano GR,Quehenberger O,Steinberg D The 94- to 97-kDa mouse macrophage membrane protein that recognizes oxidized low density lipoprotein and phosphatidylserine-rich liposomes is identical to macrosialin, the mouse homologue of human CD68. Proc Natl Acad Sci U S A 1995 92:9580 ** PubMed

9. Ramprasad MP,Terpstra V,Kondratenko N,Quehenberger O,Steinberg D Cell surface expression of mouse macrosialin and human CD68 and their role as macrophage receptors for oxidized low density lipoprotein. Proc Natl Acad Sci U S A 1996 93:14833 ** PubMed

10. Stockinger, H., Leukocyte Typing IV, (ed. W. Knapp et al.) pp. 841-843.Oxford University Press, Oxford (1989)

11. Strobl H,Scheinecker C,Csmarits B,Majdic O,Knapp W Flow cytometric analysis of intracellular CD68 molecule expression in normal and malignant haemopoiesis. Br J Haematol 1995 90:774 * PubMed

WWW RESOURCES

Portions copyright by Garland Press and by the International Workshops on Human Leukocyte Differentiation Antigens; used with permission

Modified 10/14/99   mpr@mail.nih.gov