Description

Nori Rat CXCR4 ELISA Kit Summary

Alternative names for CXCR4: C-X-C chemokine receptor type 4 (CXCR-4), fusin or CD184

Standard Curve

Kit Components
1. Pre-coated 96-well Microplate
2. Biotinylated Detection Antibody
3. Streptavidin-HRP Conjugate
4. Lyophilized Standards
5. TMB One-Step Substrate
6. Stop Solution
7. 20 x PBS
8. Assay Buffer

Other Materials Required but not Provided:
1. Microplate Reader capable of measuring absorption at 450 nm
2. Log-log graph paper or computer and software for ELISA data analysis
3. Precision pipettes (1-1000 µl)
4. Multi-channel pipettes (300 µl)
5. Distilled or deionized water

Protocol Outline
1. Prepare all reagents, samples and standards as instructed in the datasheet.
2. Add 100 µl of Standard or samples to each well and incubate 1 h at RT.
3. Add 100 µl of Working Detection Antibody to each well and incubate 1 h at RT.
4. Add 100 µl of Working Streptavidin-HRP to each well and incubate 20 min at RT.
5. Add 100 µl of Substrate to each well and incubate 5-30 min at RT.
6. Add 50 µl of Stop Solution to each well and read at 450 nm immediately.

Background:

C-X-C chemokine receptor type 4 (CXCR-4) also known as fusin or CD184 is a protein that is encoded by the CXCR4 gene.^[1]  CXCR-4 is an alpha-chemokine receptor specific for stromal-derived-factor-1 (SDF-1 also called CXCL12), a molecule endowed with potent chemotactic activity for lymphocytes.^[2] HIV uses CXCR4 to infect CD4+ T cells. It is unclear as to whether the emergence of CXCR4-using HIV is a consequence or a cause of immunodeficiency. CXCR4 is upregulated during the implantation window in natural and hormone replacement therapy cycles in the endometrium, producing, in presence of a Rat blastocyst, a surface polarization of the CXCR4 receptors suggesting that this receptor is implicated in the adhesion phase of Rat implantation. CXCR4’s ligand SDF-1 is known to be important in hematopoietic stem cell homing to the bone marrow and in hematopoietic stem cell quiescence. It has been also shown that CXCR4 signaling regulates the expression of CD20 on B cells. Until recently, SDF-1 and CXCR4 were believed to be a relatively monogamous ligand-receptor pair. Recent evidence demonstrates ubiquitin is also a natural ligand of CXCR4.^[3] Ubiquitin is best known for its intracellular role in targeting ubiquitylated proteins for degradation via the ubiquitin proteasome system. Evidence in numerous animal models suggests ubiquitin is anti-inflammatory immune modulator and endogenous opponent of proinflammatory damage associated molecular pattern molecules. MIF is an additional ligand of CXCR4.^[4] CXCR4 is present in newly generated neurons during embryogenesis and adult life where it plays a role in neuronal guidance. The levels of the receptor decrease as neurons mature. CXCR4 mutant mice have aberrant neuronal distribution. This has been implicated in disorders such as epilepsy.^[5] CXCR4 dimerization is dynamic and increases with concentration.^[6]

References

1. Moriuchi M, et al. (1997). Journal of Immunology. 159 (9): 4322–9.
2. Kryczek I, et al. (2007). American J Physiol. Cell Physiol. 292 (3): C987-95.
3. Saini V, et al. (2010). The Journal of Biological Chemistry. 285 (20): 15566–76.
4. Bernhagen J, et al. (2007). Nature Medicine. 13 (5): 587–96.
5. Bagri A, et al. (2002). Development. 129 (18): 4249–60.
6. Işbilir A, et al. (2020). Proc Natl Acad Sci USA. 117 (46): 29144–29154.

Product Citation

40.