Anti-Human CD68 (Clone KP1) – Purified No Carrier Protein

Clone KP1 is a monoclonal antibody that targets human CD68, a glycoprotein commonly used as a marker for macrophages and monocytes in tissue sections and cell preparations.

In in vivo mouse studies, clone KP1 is generally used for:

• Immunohistochemical staining of human macrophages or monocytes in xenograft models, where human cells are engrafted into mice, such as studies on humanized mice or tumor xenografts.
• KP1 has specificity for human CD68, not mouse CD68. Reports indicate it does not cross-react with mouse tissues but may react with some non-human primates and rats at reduced efficiency.
• Application protocols (such as immunohistology or flow cytometry) often require samples from mice that have been engrafted with human hematopoietic cells or tissues. In these settings, KP1 enables researchers to identify and track human macrophages or monocytes within the mouse host.

Key usage details:

• Typical applications: Immunohistology (paraffin), immunofluorescence, flow cytometry, and western blotting of human cells within mouse tissues.
• Research use: KP1 cannot be used to stain endogenous (native) mouse macrophages, only human cells in mouse tissues.
• Experimental design: Often used to assess human cell engraftment, study tumor-associated macrophages of human origin, or examine immune cell infiltration in human cell/tissue xenograft models.

Summary Table: Human CD68 (Clone KP1) Use in Mouse Studies

Additional notes:

• KP1 has been widely used for identifying human macrophages in the context of human-mouse chimeric studies, tumor microenvironment analysis, or human hematopoietic system engraftment work.
• It is ineffective for tracking mouse macrophages; alternative rat or mouse-specific CD68 antibodies should be used if murine macrophages need to be detected.

If you have a specific in vivo mouse model in mind (e.g., human tumor xenograft, humanized immune system mouse), KP1 serves to delineate and study only the human myeloid compartment within the murine background.

The correct storage temperature for sterile packaged clone KP1 (anti-CD68 antibody) depends on the supplier and formulation, but most authoritative supplier instructions indicate:

• Short-term storage (up to 1 month): 2–8°C (refrigerator) is generally acceptable for sterile, functional-grade, or working aliquots.
• Long-term storage: -20°C (freezer) is recommended for most formulations to preserve antibody stability and avoid repeated freeze/thaw cycles.

Some manufacturers also recommend aliquoting the product upon first thaw and storing aliquots at -20°C to avoid multiple freeze-thaw cycles. For even longer-term preservation or for highly labile formulations, -70°C may be advised, but this is less common for routine laboratory use.

Always check the specific datasheet provided with your product, as formulations and stabilization can differ by supplier. If your KP1 clone antibody is in a proprietary stabilized format, some products may specify exclusive refrigerator storage at 2–8°C. If not specified, default to -20°C storage for long-term use.

Essential points:

• -20°C for most anti-CD68 [KP1] antibodies.
• Avoid repeated freeze/thaw cycles.
• If sterile and stored for ?1 month, 2–8°C is acceptable. For longer periods, revert to freezer conditions.

If your product’s packaging or datasheet diverges from these norms, follow the instructions provided with your specific lot.

Other commonly used antibodies and proteins in the literature with KP1 (anti-CD68) include markers for identifying monocyte/macrophage lineage, such as CD14, CD163, and CD11b, as well as proteins that distinguish related immune cell populations or provide context in tissue studies. Additionally, other markers such as CD3 and CD20 are often used in combination for distinguishing T and B lymphocytes, respectively, especially in immunohistochemistry panels for tissue characterization.

Key details and context:

• KP1/CD68 is a widely used marker for macrophages, but it also stains myeloid precursors, peripheral blood granulocytes, and in rare cases, plasmacytoid T cells, mast cells, and some neoplasms.
• CD14 is commonly used alongside KP1 for monocyte characterization.
• CD163 provides more specificity for tissue macrophages, distinguishing them from other monocyte-derived cells.
• CD11b acts as a myeloid marker helpful in differentiating cell subsets within inflamed or diseased tissue.
• In histopathology, CD3 (T cells) and CD20 (B cells) are often part of the same immunohistochemistry panels as KP1/CD68 to help define the immune cell landscape within the sample.
• KP1 is noted for detecting a 110 kDa molecule in macrophages and sometimes 70 and 40 kDa bands in certain preparations, indicating that additional lysosomal or myeloid markers may appear in multi-antibody studies.

The choice of antibody combinations is context-dependent and often tailored to distinguish between different immune cell types, diagnose hematopoietic neoplasms, or characterize tissue inflammation and tumor microenvironments.

Key findings from scientific literature regarding clone KP1 center on two main research areas: its use as an antibody for CD68 detection in human tissues and its role in bacteriophage research. The majority of high-impact citations relate to the original monoclonal antibody, KP1, used for immunohistochemistry in pathology.

1. KP1 antibody as a marker for monocyte/macrophage lineage:

• KP1 is a monoclonal antibody raised against lysosomal fractions of human lung macrophages, recognizing a fixation-resistant epitope present in a wide array of tissue macrophages (including Kupffer cells, splenic, germinal center, and lamina propria macrophages) and granulocyte precursors. This wide cellular reactivity was confirmed in both normal and reactive lymphoid tissues.
• KP1 identifies a molecule of approximately 110 kDa in macrophage-rich human tissue, with additional bands at 70 kDa and 40 kDa detected by Western blotting.
• While highly effective as a pan-macrophage/monocytic marker, KP1 shows little to no staining of Langerhans cells and follicular dendritic cells, and only limited staining of interdigitating reticulum cells.
• Clinical utility: KP1 has become a widely used tool in surgical pathology for diagnosing disorders of the monocyte/macrophage system, including both reactive and neoplastic (malignant) histiocytic proliferations (e.g., histiocytosis, certain lymphomas).
• Target antigen: Further studies identified the antigen detected by KP1 as CD68, a heavily glycosylated type I transmembrane protein associated with lysosomal/endosomal compartments, but also present on some other cell types including neutrophils and some non-macrophage cells, which can limit its specificity.

2. Broader tissue and tumor reactivity:

• KP1 (anti-CD68) immunoreactivity has been demonstrated in various healthy and pathologically altered tissues, including inflammatory diseases like rheumatoid arthritis and osteoarthritis, as well as a wide range of neoplasms.
• CD68, though commonly used as a macrophage marker, is not entirely macrophage-specific, as KP1 also stains certain other hematopoietic cells.

3. KP1 in bacteriophage research (distinct context):

• Separately, the designation "KP1" is used in microbiology to refer to a Klebsiella pneumoniae bacteriophage. This KP1 phage has a 167,989 bp linear genome, low GC content (39.6%), and encodes 295 genes, including 14 tRNA genes. It is a member of the Myoviridae family, and research has focused on its genetics and potential as a therapeutic phage against K. pneumoniae, a multidrug-resistant pathogen.

The most prominent scientific literature citations for "clone KP1" concern its antibody form and its major role in pathology as a reagent for CD68 detection in macrophage/monocytic lineage and related tissue studies. When interpreting citations, attention must be paid to context, as "KP1" can refer to both the monoclonal antibody and a phage clone in different fields.