Protein Laboratories Rehovot Ltd.
January 2018

Certificate of Analysis & Data Sheet

We are the ONLY company producing leptin antagonists and leptins of farm animals including several fish species.

Pegylated human, mouse, rat and ovine leptins and corresponding leptin antagonists are now available!!!

PLR provides a novel service of pegylation of either existing, or provided or custom-made proteins. All PLR's proteins are carrier free (cf) and can be sold in any requested amount !!!
Human Interleukin 22 (mIL-22) antagonist (Y51A) CYT-19
Description: IL-22 is a member of the IL-10 family of regulatory cytokines which includes IL-10, IL-19, IL-20, IL-22, IL-24 and IL-26. Members of this family share partial homology in their amino acid sequences, but they are dissimilar in their biological functions. Produced by T lymphocytes, IL-22 inhibits IL-4 production by Th2 cells, and induces acute phase reactants in the liver and pancreas. IL-22 signals through a receptor system consisting of IL-10R-beta/CRF2-4 and IL-22R, both of which are members of the class II cytokine-receptor family. Recombinant human IL-22 mutant Y51A (numbering according to human IL-22 including signal peptide) produced in E.Coli is a single, non-glycosylated polypeptide chain containing 147 amino acids and having a molecular mass of 16.7 kDa. Preparation of recombinant hIL-22 antagonists provides new tools for the study of IL-22 activity and of eventual therapeutic means for attenuating its negative effects. It was prepared similarly to that described by L. Niv-Spector et al. Protein Eng Des Sel. (PEDS) 25:397-404 (2012).  
Source: E. coli 
Lot Number:  
Quantity Shipped:  
Physical Appearance: White powder 
Formulation: Interleukin-22 Y51A is lyophilized from a concentrated (1mg/ml) solution in water containing NaHCO3.
 
Solubility: It is recommended to reconstitute the lyophilized IL-22 Y51A in sterile H2O not less than 100µg/ml, which can then be further diluted to other aqueous solutions containing carrier protein such as BSA, HSA or similar.
 
Stability: Lyophilized IL-22 Y51A although stable at 4C, should be stored desiccated below -18C. Upon reconstitution interleukin-22 Y51A should be stored at 4C between 2-7 days and for future use below -18C. 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 98.0% as determined by:
(a) Analysis by reducing and non-reducing SDS-PAGE Silver Stained gel.
(b) Gel filtration chromatography under non-denaturing conditions. 
Amino Acid Sequence: The sequence of the first five N-terminal amino acids was determined and was found to be Ala-Pro-Ile-Ser-Ser. 
Dimers and Aggregates: Less than 2% as determined by gel filtration under non-denaturing conditions.
 
Biological Activity: PLR’s human IL-22 Y51A mutant is capable of full inhibition of STAT3 phosphorylation induced by mouse interleukin 22 in HepG cells. Its affinity toward immobilized mIL-22 receptor α1 extracellular domain (mIL-22 Rα1-ECD) or IL-22 binding protein is similar to the non mutated mouse interleukin 22. Human IL-22 antagonist (Y51A) has no agonistic activity in this bioassay.  
Endotoxin: Less than 0.05 ng/µg (0.5 EU/µg) of recombinant IL-22 (Y51A).
 
Protein content: Protein quantitation was carried out by UV spectroscopy at 280 nm using the absorbency value of 0.18 as the extinction coefficient for a 0.1% (1mg/ml) solution. This value is calculated by the DNAman computer analysis program of protein sequences.
 
Usage: PRL's products are furnished for LABORATORY RESEARCH USE ONLY. The product may not be used as drugs, agricultural or pesticidal products, food additives or household chemicals.  
Date Shipped: 29.11.2012