Certificate of Analysis and Data Sheet

Source:
E.Coli

Catalog No.
PRO-368

Description :

MICB (MHC class I chain-related gene B) is a transmembrane glycoprotein that functions as a ligand for human NKG2D. A closely related protein, MICA, shares 85% amino acid identity with MICB. These 2 proteins are distantly related to the MHC class I proteins. MICA and MICB (MICA/B) possess three extracellular immunoglobulin-like domains, but have no capacity to bind peptide or interact with β2-microglobulin. The genes encoding MICA/B are found within the major histocompatibility complex on human chromosome 6. The MICB locus is polymorphic with more than 15 recognized human alleles. MICA/B are minimally expressed on normal cells, but are frequently expressed on epithelial tumors and can be induced by bacterial and viral infections. MICA/B are ligands for NKG2D, an activating receptor expressed on NK cells, NKT cells, γδ T cells, and CD8+ αβ T cells. Recognition of MICA/B by NKG2D results in the activation of cytolytic activity and/or cytokine production by these effector cells. MICA/B recognition is involved in tumor surveillance, viral infections, and autoimmune diseases. The release of soluble forms of MICA/B from tumors down-regulates NKG2D surface expression on effector cells resulting in the impairment of anti-tumor immune response.

Description :

rHuMICB produced in E.Coli is a single, non-glycosylated polypeptide chain containing 326 amino acids and having a molecular mass of 37kDa. The sequence contains the extracellular domain of the mature human MICB (amino acid residues Ala23 ?Tyr312)
MICB is purified by proprietary chromatographic techniques.

Physical Appearance:

Sterile Filtered White lyophilized (freeze-dried) powder.

Formulation:

Lyophilized from a concentrated (1mg/ml) solution containing no additives.

Solubility:

It is recommended to reconstitute the lyophilized MICB in sterile 18MΩ-cm H₂O not less than 100ug/ml, which can then be further diluted to other aqueous solutions.

Stability:

Lyophilized Recombinant Human MICB although stable at room temperature for 3 weeks, should be stored desiccated below -18⁰C. Upon reconstitution MICB should be stored at 4⁰C between 2-7 days and for future use below -18⁰C. For long term storage it is recommended to add a carrier protein (0.1% HSA or BSA).
Please avoid freeze-thaw cycles.

Purity:

Greater than 95.0% as determined by:
(a) Analysis by RP-HPLC.
(b) Anion-exchange FPLC.
(c) Analysis by reducing and non-reducing SDS-PAGE Silver Stained gel.

Dimers and aggregates:

Less than 1% as determined by silver-stained SDS-PAGE gel analysis.

Biological Activity:

ProSpec旧 Recombinant Human MICB is fully biologically active when compared to standards. Measured by its ability to bind MICB antibody in ELISA.

Endotoxin:

Less than 0.1 ng/ug (IEU/ug) of Recombinant Human MICB.

Protein content:

Protein quantitation was carried out by two independent methods:
1. UV spectroscopy at 280 nm.
2. Analysis by RP-HPLC, using a standard solution of MICB as a Reference Standard.

Usage:

This material is offered by ProSpec-TechnoGene for research, laboratory or further manufacturing purposes.

Latest Publications:

1. The haplotype block, NFKBIL1-ATP6V1G2-BAT1-MICB-MICA, within the class III-class I boundary region of the human major histocompatibility complex may control susceptibility to hepatitis C virus-associated dilated cardiomyopathy.
Tissue Antigens 2005 Sep;66(3):200-8
2. [Effect of hypoxia/reoxygenation (H/R) on expression of MICA and MICB in human hepatocytes]
Sichuan Da Xue Xue Bao Yi Xue Ban 2005 Mar;36(2):157-60
3. [The study on the haplotype of MICA and MICB microsatellite locus in Guangzhou Han population.]
Yi Chuan 2004 May;26(3):291-4
4. Study on the haplotypes of MICA and MICB microsatellite and HLA-B locus in the Guangzhou Han population.
Tissue Antigens 2004 Sep;64(3):281-5
5. Eight novel MICB alleles, including a null allele, identified in gastric MALT lymphoma patients.
Tissue Antigens 2004 Sep;64(3):276-80
6. [The polymorphism distributions of MICA and MICB microsatellite in Guangdong Han population]
Zhonghua Yi Xue Yi Chuan Xue Za Zhi 2004 Jun;21(3):294-6