| 摘要 |
PROBLEM TO BE SOLVED: To obtain a new polypeptide comprising a polypeptide of Psathyrella velutina lectin, containing a specific amino acid sequence, recognizing an agalacto IgG specific to chronic arthrorheumatism (RA)patient and capable of expecting application of RA to diagnosis. SOLUTION: This new polypeptide of Psathyrella velutina lectin contains at least an amino acid sequence represented by the formula (Xaa is an arbitrary amino acid and amino acid in parenthesis represents that the amino acid may not exist) and in serum of RA patient, agalacto IgG in which galactose of saccharide chain bound to 297th asparagine residue is lost is abnormally increased and since Psathyrella velutina specifically recognizes the agalacto IgG, possibility of RA to diagnosis is expected. The polypeptide obtained by separating mRNA from fruit body of Psathyrella velutina lectin, preparing cDNA library by using the mRNA, screening the cDNA library with anti-Psathyrella velutina antibody, binding the resultant gene to a vector and expressing the DNA by the host. |
