Type IV chitinase quantification in four different grape cultivars (Vitis vinifera) in northeast of Iran by an indirect sandwich enzyme-linked immunosorbent assay.

The incidence of grape (Vitis vinifera) allergy in the northeast of Iran is second to melon allergy. Type IV chitinase is one of the major grape allergens. The current study investigates the level of type IV chitinase in four grape variants for the first time in Khorasan Razavi Province using a highly sensitive sandwich enzyme-linked immunosorbent assay (ELISA). This assay was developed using a polyclonal antibody as a capture antibody and monoclonal antibody as a secondary one. Finally, the amount of type IV chitinase was measured by the validated ELISA test. The sensitivity of the developed sandwich ELISA is 16 ± 0.05 ng/ml, and its mean coefficients of intraday and interday variations are <5% and <15%, respectively. The recovery of the designed ELISA is 64 ± 0.9 %. The assessments showed that the highest level of type IV chitinase was 39.7 ± 2.3 µg/g in Peykani grape, whereas in the Sultana cultivar, it was 1.76 ± 0.1 µg/g. According to the data, the level of type IV chitinase is variable in different cultivars, and hence, it will be helpful for clinicians to recommend a less allergenic variety to the patient.