Tomato endo beta-mannanase: A candidate of potential tomato allergen protein detected with human monoclonal antibody established from a patient suffered from Japanese cedar pollinosis.

Peripheral blood lymphocytes from a patient allergic to Japanese cedar pollens were transformed by Epstein-Barr virus infection. Some transformed B-lymphoblastoid cells (BLCs) secreted IgM class antibodies to cedar pollen extracts and tomato fruit extracts. One stable human-mouse hybridoma clone Y-22-3-3 secreting IgM class monoclonal antibody to tomato fruit extracts was established by cell fusion of BLCs with mouse myeloma cells. Western blot analysis of tomato extracts showed Y-22-3-3 monoclonal antibody recognized a tomato protein with a molecular weight of 40 kDa. The CBB-stained 40 kDa protein from antibody-affinity chromatography was analyzed by MALDI-TOF/TOF, and identified as tomato endo-beta-mannanase, which was previously reported as one of the potential candidates for tomato allergens.