HUMAN-LYMPHOCYTE FC RECEPTOR FOR IGE - SEQUENCE HOMOLOGY OF ITS CLONED CDNA WITH ANIMAL LECTINS

We have purified the human lymphocyte Fc receptor specific for IgE (Fc.epsilon. receptor) and its soluble form by using the anti-Fc.epsilon. receptor monoclonal antibody H107. Using an oligonucleotide probe corresponding to the partial amino acid sequence of the soluble Fc.epsilon. receptor related to IgE binding factor, we cloned, sequenced, and expressed a cDNA for the receptor. The Fc.epsilon. receptor has 321 amino acid residues with no NH2-terminal signal sequence. The receptor was separated into two domains by a putative 24-amino acid residue transmembrane region located near the NH2-terminal end. The Fc.epsilon. receptor showed a marked homology with animal lectins including human and rat asialoglycoprotein receptors, chicken hepatic lectin, and rat mannose binding proteins.