Development and characterization of monoclonal antibodies for the mycotoxin citreoviridin

Authors: Maragos, Chris; UCHIYAMA, YOSUKE - Azabu University; KOBAYASHI, NAOKI - Azabu University; SUGITA-KONISHI, YOSHIKO - Azabu University

Submitted to: Toxins
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/28/2019
Publication Date: 10/30/2019
Citation: Maragos, C.M., Uchiyama, Y., Kobayashi, N., Kominato, F., Sugita-Konishi, Y. 2019. Development and characterization of monoclonal antibodies for the mycotoxin citreoviridin. Toxins. 11(11):630. https://doi.org/10.3390/toxins11110630.
DOI: https://doi.org/10.3390/toxins11110630

Interpretive Summary: Shoshin beriberi, also known as heart attacking paralysis, was, in the early 20th century, a significant contributor to mortality in Japan. The disease, which is now rare in developed countries, results from thiamine (vitamin B1) deficiency. Early research linked Shoshin beriberi with a toxin (citreoviridin) produced in rice contaminated with the mold Penicillium citreonigrum. Citreoviridin has also been found in maize, pecan nuts, and wheat products. Scientists at the Agricultural Research Service in Peoria, Illinois, in collaboration with scientists at Azabu University (Kanagawa, Japan), developed an assay for rapid screening of the toxin in polished white rice. The assay developed provides a tool for diverting potentially contaminated rice from the human food and animal feed supplies.

Technical Abstract: Citreoviridin (CTV) in an inhibitor of mitochondrial ATPase. It has been isolated from molded (yellow) rice and linked to the human disease Shoshin-Kakke (acute cardiac beriberi). Purified CTV can reproduce the symptoms in experimental animals. Beriberi is caused by thiamine deficiency, and the link between CTV and Shoshin-Kakke has been difficult to resolve, in part because cases of the disease are rare. In addition to rice, CTV has been found in maize, pecan nuts, and wheat products. A method to screen for CTV and its geometric isomer (iso-CTV) in commodities was developed, based upon the development of two novel monoclonal antibodies (mAb). In an antigen immobilized competitive enzyme-linked immunosorbent assay format (CI-ELISA), the observed IC50s for CTV were 11 ng/mL and 18 ng/mL (mAbs 2-2 and 2-4, respectively). The assays were relatively tolerant to methanol and acetonitrile, which allowed their application to the detection of CTV in spiked polished white rice. Using a matrix-matched calibration, the dynamic range of the mAb 2-4 based ELISA was equivalent to 0.23 to 2.22 mg/kg of a mixture of CTV and iso-CTV. Recoveries over the range of 0.36 to 7.23 mg/kg averaged 97 ± 10%. Both mAbs also significantly enhanced the native fluorescence of CTV. The results suggest that the CI-ELISA with mAb 2-4 can be applied to the screening of white rice for CTV.