Anti-Human CD68 – APC

This Allophycocyanin (APC) conjugate is formulated in 0.01 M phosphate buffered saline (150 mM NaCl) PBS pH 7.4, 1% BSA and 0.09% sodium azide as a preservative.

This Allophycocyanin (APC) conjugate is stable when stored at 2-8°C. Do not freeze.

Functional grade preclinical antibodies may be stored sterile as received at 2-8°C for up to one month. For longer term storage, aseptically aliquot in working volumes without diluting and store at -70°C. Avoid Repeated Freeze Thaw Cycles.

Red Laser (650 nm)

IHC^{5, 7, 8, 9, 10, 11},
IHC FFPE¹⁰,
IP^{1, 4, 10, 12},
ICFC^{5, 7},
ICC^{4, 12},
Dot¹²,
B¹²,
EM²,

Anti-CD68 antibody (clone KP1) activity is directed against human CD68.

CD68 is found in the cytoplasm of monocytes/macrophages, fibroblasts, human peripheral blood lymphocytes, neutrophil primary and mast cell granules, large granular lymphocytes, basophils, basal epithelial cell layers, renal glomeruli, myeloid cells, endothelial cells, retinal epithelial cells, osteoblasts, fibroblast-like cells from bone marrow, and a wide-range of lymphoid neoplasms. CD68 is predominantly located in lysosomal membranes, with a small amount on the cell surface. Additionally, CD68 can be expressed in most hematopoietic cell lines by phorbol-induced differentiation; soluble CD68 can also be found in serum and urine.

CD68 is a heavily glycosylated type I transmembrane glycoprotein belonging to the lysosomal-associated membrane protein (LAMP) family and may play a role in endocytosis or lysosomal traffic and phagocytic activities¹. CD68 localizes to endosome- or lysosome-like structures². Additionally, LAMPS have been implicated in tumor cell metastasis and are over-expressed on the surface of metastatic compared with nonmetastatic cell lines³.

KP1 was originally used as a pan-monocytic/macrophage marker against CD68; however, CD68 is not a macrophage specific antigen and KP1 is known to stain neutrophils and other non-macrophage-like cells^4,5,6,7,8. KP1 reacts against CD68 in a wide range of healthy⁴ and disease-associated (rheumatoid arthritis and osteoarthritis)⁵ tissues as well as a variety of neoplasms⁹, tumor cell lines⁷, and tumor-associated macrophages ⁸. KP1 detects a fixation-resistant epitope¹⁰ that is likely glycan-based^1,9 which is shared by many cell types⁷.

KP1 was developed by immunizing Balb/c mice against a lysosomal fraction of human lung ¹⁰. Hybridoma supernatants derived from spleen cells were screened on cryostat human lung and tonsil sections as well as paraffin wax sections of lung tissue fixed in formol saline.

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8. Frafjord A, Skarshaug R, Hammarström C, et al. Scand J Immunol. 92(1):e12889. 2020.
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11. Smith ME, Costa MJ, Weiss SW. Am J Surg Pathol. 15(8):757-763. 1991.
12. Micklem K, Rigney E, Cordell J, et al. Br J Haematol. 73(1):6-11. 1989.