Recombinant Human SLAMF4 (CD244/2B4)-Fc Chimera (carrier-free)

Pricing & Availability
Regulatory Status
Other Names
SLAMF4, SLAM family member 4, 2B4, Natural killer cell receptor 2B4, NK cell activation-inducing ligand, NAIL, NK cell type I receptor protein 2B4, NKR2B4, h2B4, signaling lymphocytic activation molecule 4, CD244
Ave. Rating
Submit a Review
Product Citations
Recombinant human SLAMF4/CD244 induces the production of IFN-γ in human NK-92 cells in a dose dependent manner. The ED50 for this effect is 0.5 – 2.5 µg/mL.
  • Human_SLAMF4-Fc_Chimera_CF_1_061119.png
    Recombinant human SLAMF4/CD244 induces the production of IFN-γ in human NK-92 cells in a dose dependent manner. The ED50 for this effect is 0.5 – 2.5 µg/mL.
  • Human_SLAMF4-Fc_Chimera_CF_2_061119.png
    Stability Testing for Recombinant Human SLAMF4. Recombinant Human SLAMF4 was aliquoted in PBS, pH7 at 0.2 mg/mL.One aliquot was frozen and thawed four times (4x Freeze/Thaw) and compared to the control that was kept at 4°C (Control). The samples were tested for their ability to induce the production of IFNγ in human NK-92 cells in a dose dependent manner. The ED50 for this effect is 0.5 – 2.5 µg/mL.
Cat # Size Price Quantity Check Availability Save
784202 10 µg $112
Check Availability

Need larger quantities of this item?
Request Bulk Quote
784204 25 µg $229
Check Availability

Need larger quantities of this item?
Request Bulk Quote
784206 100 µg $675
Check Availability

Need larger quantities of this item?
Request Bulk Quote
784208 500 µg $1465
Check Availability

Need larger quantities of this item?
Request Bulk Quote

SLAMF4, also known as 2B4 and CD244, is one of the members of the CD2 subfamily. It is expressed on NK cells, monocytes, basophils, TCR γ/δ T cells, and a subset of CD8+ T cells. Engagement of SLAMF4 by antibodies or a natural ligand, such as CD48, leads to tyrosine phosphorylation of SLAMF4, cell-mediated cytotoxicity and IFN-γ secretion by NK cells. Except CD48 ligation, SLAMF4-mediated non-MHC-restricted cell cytotoxicity is also dependent on others NCRs, such as NKp46 (NCR1/CD335). However, engagement of SLAMF4 with inhibitory receptors, such as KIR2DL1 or NKG2 (CD94), blocks SLAMF4-mediated cell cytotoxicity and cytokine production. The cytoplasmic region of SLAMF4 contains several immunoreceptor tyrosine-based switch motifs (ITSMs), which serve as activating and inhibitory regulatory elements for SLAMF4-mediated signaling. Its ITSMs can not only bind to SAP and Src kinase Fyn but also recruit the inhibitory kinase, Csk, and phosphatase SHP-1, SHP-2, and SHIP, leading to positive and negative signaling on cells. The activating and inhibitory functions are dependent on the density of surface expression of SLAMF4, degree of ligation, and the level of the adaptor molecule SAP expression. In XLP (X-linked lymphoproliferative disease) patients, SLAMF4 engagement cannot activate NK cells due to impairment of SAP/SH2D1A association. It has shown that SLAMF4 interacts with CD48 and functions as a costimulatory molecule, playing a critical role in cell proliferation and MHC-restricted cytotoxicity in CD8+ T cells. SLAMF4 expression also correlates with T cell differentiation. CD8+ effector αβ T cells predominantly express surface SLAMF4 with high levels of granzyme B and perforin expression, and rapid production of IFN-γ.

Product Details
Technical data sheet

Product Details

Human SLAMF4, amino acid (Cys22-Arg221) (Accession: # NP_057466.1), with a linker (GSSR) and a C-terminal human IgG (Pro100-Lys330), was expressed in 293E cells.
Molecular Mass
The 435 amino acid recombinant protein has a predicted molecular mass of approximately 48.58 kD. The DTT-reduced and non-reduced protein migrates at between 66 kD and 120 kD respectively by SDS-PAGE. The predicted N-terminal amino acid is Cys.
>95%, as determined by Coomassie stained SDS-PAGE.
0.22 μm filtered protein solution is in PBS pH7.2.
Endotoxin Level
Less than 0.1 EU per µg protein as determined by the LAL method.
10 and 25 µg sizes are bottled at 200 µg/mL. 100 µg size and larger sizes are lot-specific and bottled at the concentration indicated on the vial. To obtain lot-specific concentration and expiration, please enter the lot number in our Certificate of Analysis online tool.
Storage & Handling
Unopened vial can be stored between 2°C and 8°C for up to 2 weeks, at -20°C for up to six months, or at -70°C or colder until the expiration date. For maximum results, quick spin vial prior to opening. The protein can be aliquoted and stored at -20°C or colder. Stock solutions can also be prepared at 50 - 100 µg/mL in appropriate sterile buffer, carrier protein such as 0.2 - 1% BSA or HSA can be added when preparing the stock solution. Aliquots can be stored between 2°C and 8°C for up to one week and stored at -20°C or colder for up to 3 months. Avoid repeated freeze/thaw cycles.
The ED50 is 0.5 - 2.5 µg/mL, as measured by the ability of immobilized protein to induce IFN-γ production by NK-92 cells. Human IFN-γ ELISA MAX™ Deluxe Kit (Cat. No. 430104) was used to measure IFN-γ production.


Application Notes

BioLegend carrier-free recombinant proteins provided in liquid format are shipped on blue ice. Our comparison testing data indicates that when handled and stored as recommended, the liquid format has equal or better stability and shelf-life compared to commercially available lyophilized proteins after reconstitution. Our liquid proteins are verified in-house to maintain activity after shipping on blue ice and are backed by our 100% satisfaction guarantee. If you have any concerns, contact us at

Antigen Details

CD2 subfamily

NK cells, monocytes and basophils, TCR γ/δ T cells, and a subset of CD8+ T cells.

Engagement of SLAMF4 with CD48 stimulates cell-mediated cytotoxicity and cytokine secretion.
Fyn, SAP/SH2D1A, Csk, SHP-1, SHP-2, SHIP
Recombinant human SLAMF4 induces the production of IFN-γ in human NK-92 cells.
Cell Type
Basophils, Monocytes, NK cells, T cells
Biology Area
Molecular Family
CD Molecules, Soluble Receptors
Antigen References
  1. Parolini S, et al. 2000. J Exp Med. 192: 337.
  2. Watzl C, et al. 2000. J Immunol. 165: 3545.
  3. Brown MH, et al. 1998. J Exp Med. 188: 2083.
  4. Watzl C, et al. 2000. J Immunol. 165: 3545.
  5. Eissmann P, et al. 2005. Blood. 105: 4722.
  6. Latchman Y, et al. 1998. J Immunol. 161: 5809.
  7. Speiser DE, et al. 2001. J Immunol. 167: 6165.
  8. Lee KM, et al. 2003. J Immunol. 170: 4881.
  9. Kambayashi T, et al. 2001. J Immunol. 167: 6706.
  10. Tangye SG, et al. 1999. J Immunol. 162: 6981.
  11. Nakajima H, et al. 1999. Eur J Immunol. 29: 1676.
  12. Schuhmachers G, et al. 1995. Eur J Immunol. 25: 1117.
  13. Sivori S, et al. 2000. Eur J Immunol. 30: 787.
Gene ID
51744 View all products for this Gene ID
View information about SLAMF4 on

Related FAQs

Why choose BioLegend recombinant proteins?

     • Each lot of product is quality-tested for bioactivity as indicated on the data sheet.
     • Greater than 95% Purity or higher, tested on every lot of product.
     • 100% Satisfaction Guarantee for quality performance, stability, and consistency.
     • Ready-to-use liquid format saves time and reduces challenges associated with reconstitution.
     • Bulk and customization available. Contact us.
     • Learn more about our Recombinant Proteins.

How does the activity of your recombinant proteins compare to competitors?

We quality control each and every lot of recombinant protein. Not only do we check its bioactivity, but we also compare it against other commercially available recombinant proteins. We make sure each recombinant protein’s activity is at least as good as or better than the competition’s. In order to provide you with the best possible product, we ensure that our testing process is rigorous and thorough. If you’re curious and eager to make the switch to BioLegend recombinants, contact your sales representative today!

What is the specific activity or ED50 of my recombinant protein?

The specific activity range of the protein is indicated on the product datasheets. Because the exact activity values on a per unit basis can largely fluctuate depending on a number of factors, including the nature of the assay, cell density, age of cells/passage number, culture media used, and end user technique, the specific activity is best defined as a range and we guarantee the specific activity of all our lots will be within the range indicated on the datasheet. Please note this only applies to recombinants labeled for use in bioassays. ELISA standard recombinant proteins are not recommended for bioassay usage as they are not tested for these applications.

Have your recombinants been tested for stability?

Our testing shows that the recombinant proteins are able to withstand room temperature for a week without losing activity. In addition the recombinant proteins were also found to withstand four cycles of freeze and thaw without losing activity.

Does specific activity of a recombinant protein vary between lots?

Specific activity will vary for each lot and for the type of experiment that is done to validate it, but all passed lots will have activity within the established ED50 range for the product and we guarantee that our products will have lot-to-lot consistency. Please conduct an experiment-specific validation to find the optimal ED50 for your system.

How do you convert activity as an ED50 in ng/ml to a specific activity in Units/mg?

Use formula Specific activity (Units/mg) = 10^6/ ED50 (ng/mL)

Go To Top Version: 1    Revision Date: 06/11/2019

For research use only. Not for diagnostic use. Not for resale. BioLegend will not be held responsible for patent infringement or other violations that may occur with the use of our products.


*These products may be covered by one or more Limited Use Label Licenses (see the BioLegend Catalog or our website, BioLegend products may not be transferred to third parties, resold, modified for resale, or used to manufacture commercial products, reverse engineer functionally similar materials, or to provide a service to third parties without written approval of BioLegend. By use of these products you accept the terms and conditions of all applicable Limited Use Label Licenses. Unless otherwise indicated, these products are for research use only and are not intended for human or animal diagnostic, therapeutic or commercial use.


8999 BioLegend Way, San Diego, CA 92121
Toll-Free Phone: 1-877-Bio-Legend (246-5343) Phone: (858) 768-5800 Fax: (877) 455-9587


Remember me
Forgot your password? Reset Password
Request an Account