Mohamad Morsey and Yuan-zheng Zhang
- Intervet International B.V. [NL/NL]; Wim de Korverstraat 35, 5831 AN Boxmeer (NL)
- Intervet Inc., Madison, NJ (US)
The present invention provides caninized human anti-human IL-4Rα antibodies that have specific sequences and a high binding affinity for canine IL-4Rα. The invention also relates to use of these antibodies in the treatment of dogs against atopic dermatitis.
CovalX Technology Used
In order to determine the epitopes of the IL-4 receptor alpha, mass spectrometry was used. Using cross-linking, high-mass MALDI mass spectrometry and nLC-Orbitrap mass spectrometry, the epitopes that the anti-caninc IL-4Ra mAb cDupi H2-L2 recognizes were determined. The epitope mapping was performed by CovalX.
From this service, it was determined that there were two regions in the extracellular domain of canine IL-4Ra chain. The amino acid sequence for region 1 is Q WKMDHPTNC S AELRL S YQLD (SEQ ID NO: 39) and region 2 is RLAASTL SGA (SEQ ID NO: 40). The 11.-4 Ra chain that was found to be part of these sequences includes the amino acids that are in contact with the cDupi H2-L2 antibody. Specifically, the threonine residue at AA position 27, the tyrosine residue at AA position 37, the serine residue at AA position 164, the threonine residue at AA position 165, and the lysine residue at AA position 167. From this, it was determined that the amino acid sequence TNCCSAELRLSY (SEQ ID NO: 41; sub-region 1) and/or S I LK (SEQ ID NO: 42, sub-region 2) contains the epitope. Interestingly, it was found that the same amino acid residues in the canine IL-4Ru chain that were in contact with the caninized antibody (Dupi H2-L2) are identical to the corresponding amino acid residues in the human IL-4Ra sequence. Thus, it can be predicted that the epitope is the same for both the canine and human IL-4Ra sequences.