Human TLR8 Stable Cell Line

Product Discontinued

Human TLR8 Stable Cell Line Summary

• Description: The TLR8 stable cell line can be used for TLR8 flow cytometric calibration and detection control as well as TLR8-dependent functional assays. TLR8 expression in this cell line has been validated by Western blotting (fig. 1) and flow cytometry (fig. 2). Functional activity of this cell line has been validated by the NF-kB/SEAPorter™ Assay Kit (NBP2-25286, fig. 3).
  
  Contents: 3~4 x 10^6 cells
  Biosafety Level: 2
• Immunogen: The TLR8 stable cell line is a stably transfected cell line which expresses full-length human Toll-like receptor 8 (TLR8) with an N-terminal HA tag.
• Target Species: Human
• Specificity: TLR8
• Selection Agent: Blasticidin
• Growth Properties: Adherent Morphology: Epithelial
• RCL Type: Stable Cell Line
• Host: HEK293
• Gene: TLR8

Applications/Dilutions

• Agonist:
  • Imidazoquinoline Resiquimod (R-848), TLR7 and TLR8 ligand NBP2-26231
• Readout System:
  • NFkB Secreted Alkaline Phosphatase Reporter Assay Kit (Colorimetric) NBP2-25286
  • Intracellular Staining Kit NBP2-26248

Packaging, Storage & Formulations

• Storage: Store in gas phase of liquid nitrogen.
• Reconstitution Instructions: Growth Medium: DMEM with 4.5 g/L glucose + 10% FBS + 4 mM L-glutamine + 1 mM sodium pyruvate + 100 units/ml penicillin + 0.1 mg/ml streptomycin + 10 ug/ml blasticidin.

Details for Array

• Type: Cell

Notes

Assume all cultures are hazardous since they may harbor latent viruses or other organisms that are uncharacterized. The following safety precautions should be observed.
- Use pipette aids to prevent ingestion and keep aerosols down to a minimum.
- No eating, drinking or smoking while handling the stable line.
- Wash hands after handling the stable line and before leaving the lab.
- Decontaminate work surface with disinfectant or 70% ethanol before and after working with cells.
- All waste should be considered hazardous.
- Dispose of all liquid waste after each experiment and treat with bleach.

Alternate Names for Human TLR8 Stable Cell Line

• CD288 antigen
• CD288
• MGC119599
• MGC119600
• TLR8
• toll-like receptor 8

Background

Toll-like receptor 8 (TLR8) is a member of the TLR family of receptors that play a role in innate immune system activation and the recognition of pathogen-associated molecular patterns (PAMPs) or damage-associated molecular patterns (DAMPs) (1,2). TLRs are type I membrane receptors that can be expressed on either the cell surface or internally, on endosomes (1,2). TLR8 is an endosomal receptor and is activated by pathogenic single stranded (ss) RNA (1-3). TLR8 is located on the X chromosome and is expressed mostly in monocytes/macrophages, neutrophils, and myeloid dendritic cells (1-3). Structurally, TLR8 consists of an extracellular domain, a cysteine-rich region, and transmembrane domain, and a Toll/Interleukin-1 receptor homology (TIR) domain (3,4). The extracellular domain contains a N-terminal leucine rich repeat (LRRNT) and a C-terminal LRR (LRRCT) which have 26 LRRs between them, each approximately 20-30 amino acids (aa), and a Z-loop between LRR14 and LRR15 (3). The primary isoform of the human TLR8 is synthesized as a protein 1041 aa in length with a theoretical molecular weight of ~120 kDa (4).

TLR8 is highly similar to TLR7 and both pathways are mediated by the adapter protein MyD88 to signal through IFN regulatory factor 7 (IRF7) and nuclear factor (NF)-kappaB (1-3,5). However, TLR7 recognizes guanosine and GU-rich ssRNA, while TLR8 recognizes uridine and AU-rich sequences (2,5). TLR7/TLR8 agonists, including derivatives of the immunostimulatory imiquimod, have been shown to be a promising cancer therapy capable of providing anticancer signals to antigen presenting cells (APCs), with many agonists being tested in both pre-clinical and clinical trials (6). Similarly, studies suggest that agonists for TLR8, in combination with other individual TLR agonists and antagonists, may also be useful for treating inflammatory allergic diseases, such as allergic rhinitis (7).

References

1. Sakaniwa, K., & Shimizu, T. (2020). Targeting the innate immune receptor TLR8 using small-molecule agents. Acta crystallographica. Section D, Structural biology, 76(Pt 7). https://doi.org/10.1107/S2059798320006518

2. Cervantes, J. L., Weinerman, B., Basole, C., & Salazar, J. C. (2012). TLR8: the forgotten relative revindicated. Cellular & molecular immunology. https://doi.org/10.1038/cmi.2012.38

3. Ohto, U., Tanji, H., & Shimizu, T. (2014). Structure and function of toll-like receptor 8. Microbes and infection. https://doi.org/10.1016/j.micinf.2014.01.007

4. Uniprot (Q9NR97)

5. Jannuzzi, G. P., de Almeida, J., Paulo, L., de Almeida, S. R., & Ferreira, K. S. (2020). Intracellular PRRs Activation in Targeting the Immune Response Against Fungal Infections. Frontiers in cellular and infection microbiology. https://doi.org/10.3389/fcimb.2020.591970

6. Frega, G., Wu, Q., Le Naour, J., Vacchelli, E., Galluzzi, L., Kroemer, G., & Kepp, O. (2020). Trial Watch: experimental TLR7/TLR8 agonists for oncological indications. Oncoimmunology. https://doi.org/10.1080/2162402X.2020.1796002

7. Golshiri-Isfahani, A., Amizadeh, M., & Arababadi, M. K. (2018). The roles of toll like receptor 3, 7 and 8 in allergic rhinitis pathogenesis. Allergologia et immunopathologia. https://doi.org/10.1016/j.aller.2017.09.026

Limitations

This product is for research use only and is not approved for use in humans or in clinical diagnosis. Reporter Cell Lines are guaranteed for 1 year from date of receipt.

Publications for TLR8 Reporter Cell Line (NBP2-26271)(2)

Publications using NBP2-26271

• Bernard MA, Han X, Inderbitzin S et al. HIV-Derived ssRNA Binds to TLR8 to Induce Inflammation-Driven Macrophage Foam Cell Formation. PLoS ONE 2014-08-05 [PMID: 25090652]
  
  Details:
  Using the Alexa Fluor (R) 488 conjugated version of NBP2-24917, catalog number NBP2-24917AF488.
• Feng D, Sangster-Guity N, Stone R et al. Differential requirement of histone acetylase and deacetylase activities for IRF5-mediated proinflammatory cytokine expression. J Immunol. 2010-11-15 [PMID: 20935208]

Bioinformatics

• Gene Symbol: TLR8