FITC Anti-Human CD44 Antibody

Product Details


CloneBJ18
ApplicationFlow Cytometry
ReactivityHuman
FormatFITC
Target NameCD44, H-CAM, Ly-24, gp85
Isotypemouse IgG1
Antibody TypeMonoclonal
Regulatory StatusRUO
FormulationPhosphate-buffered solution, pH 7.2, containing 0.09% sodium azide and 0.2% (w/v) BSA
Protein ConcentrationSupplied at a lot-specific concentration.
Storage & HandlingThe antibody solution should be stored undiluted between 2°C and 8°C, and protected from prolonged exposure to light. Do not freeze.
Recommended UsageFor flow cytometric staining, it is recommended to use 5 µL of this reagent per 0.5-1.0 million cells in a 100 µL volume. Optimal reagent performance should be determined by titration for each specific application. FITC has an excitation max at 493 nm and an emission max at 525 nm.
Excitation LaserBlue Laser (488 nm)
See All FormatsClone BJ18

Background Information


Human CD44 is a widely expressed type I transmembrane glycoprotein that functions as a cell adhesion molecule involved in cell-cell and cell-extracellular matrix interactions. It is expressed on numerous cell types, including leukocytes, epithelial cells, fibroblasts, endothelial cells, and many stem cells. CD44 regulates a broad range of biological processes, including lymphocyte activation and homing, leukocyte migration, tissue repair, hematopoiesis, and wound healing. Through its ability to mediate adhesion and intracellular signaling, CD44 also influences cell proliferation, survival, differentiation, and motility.

Structurally, CD44 consists of an extracellular N-terminal hyaluronan-binding domain, a stem region that undergoes extensive alternative splicing, a single transmembrane domain, and a cytoplasmic tail that interacts with cytoskeletal adaptor proteins such as ezrin, radixin, and moesin (ERM proteins). Alternative splicing generates numerous CD44 variant isoforms (CD44v), which differ in their extracellular domains and tissue distribution. The principal ligand for CD44 is hyaluronic acid (hyaluronan), a major component of the extracellular matrix. CD44 also binds osteopontin, fibronectin, collagen, laminin, matrix metalloproteinases, and select growth factors, allowing it to integrate extracellular matrix remodeling with intracellular signaling pathways.

CD44 has been implicated in numerous inflammatory, autoimmune, and malignant diseases. In chronic inflammatory disorders such as rheumatoid arthritis and inflammatory bowel disease, CD44 contributes to leukocyte recruitment and tissue inflammation. In cancer, CD44 is frequently overexpressed and serves as a marker of cancer stem cells in multiple tumor types, including breast, colorectal, pancreatic, gastric, and head and neck cancers. CD44 promotes tumor cell proliferation, epithelial-mesenchymal transition, invasion, metastasis, resistance to chemotherapy, and tumor recurrence through signaling pathways involving Ras, PI3K/AKT, Wnt/β-catenin, and receptor tyrosine kinases. Consequently, CD44 has emerged as an attractive therapeutic target. Investigational strategies include monoclonal antibodies, hyaluronan-targeted drug delivery systems, antibody-drug conjugates, nanoparticle-based therapies, CAR T-cell approaches, and inhibitors that disrupt CD44-hyaluronan interactions. These therapies aim to selectively eliminate CD44-expressing tumor cells, overcome drug resistance, and enhance the effectiveness of conventional cancer treatments while preserving normal tissue function.

Isotype Control


FITC Mouse IgG1 Isotype Control Antibody

Data Sheets


FITC Anti-Human CD44 Antibody TDS

Related Protocols


Flow Cytometry Protocol

Frequently Asked Questions


How do I determine the optimal antibody concentration/titer for my experiment?
We recommend titrating each new antibody lot on your own cell type and instrument, since optimal concentration depends on cell density, target expression level, and cytometer sensitivity. Suggested starting dilutions or test sizes (e.g., µg or µl per 10^6 cells) are provided on the product page as a starting reference point, not a fixed requirement.

Can these antibodies be used for intracellular or intranuclear staining, or only surface staining?
Intended use (surface, intracellular, or both) is specified per product, indicated under Application. The appropriate Related Protocol is linked for each product. If you need to detect both surface and intracellular markers in the same panel, confirm each antibody's compatibility with your fixation/permeabilization protocol before combining them.

What controls should I use alongside these antibodies?
Matched isotype controls (same host species, isotype, and conjugate) are available for most clones to help distinguish specific binding from background/non-specific staining and are linked on each product page. Unstained, single-color compensation, and fluorescence-minus-one (FMO) controls are also recommended, especially for multicolor panel design.

Can I combine InnoCyto Flow Cytometry antibodies into a multicolor panel?
Yes — antibodies across our catalog are designed to be panel-compatible, and conjugate options are offered specifically to support multiplexing. When building a panel, pair bright fluorophores with low-expression targets, avoid excessive spectral overlap, and confirm compensation is set up correctly for your specific fluorochrome combination. Use our Panel Builder to simplify the process.

Have a product or application question? Consult our FAQs or contact us.