TARIN, THE LECTIN FROM TARO, A NOVEL FOOD ADDITIVE THAT BOOSTS THE IMMUNOLOGICAL SYSTEM

Innovations in the field of food sciences are emerging to reveal new bioactive compounds. The addition of this compounds to food should promote health benefits for the consumers. Several studies have reported the biological and nutritional properties of Colocasia esculenta worldwide known as taro, but little is known about its action on the hematopoietic system. Therefore, the effects of tarin, a lectin (12 kDa) present in the corm of Colocasia esculenta, were analysed on mouse bone marrow cell populations. Bone marrow cells were obtained from C57BL6 mice and cultured for 5 days in the presence of tarin, growth factors (IL-3, GM-CSF and EPO) and / or medium. Moreover, tarin-FITC interaction was also evaluated in bone marrow mice cells. In vitro assays were analyzed by flow cytometry to check size versus granularity parameters and phenotype using anti-Gr-1, anti-CD3, anti-CD19 and anti-IL7Rα. By performing flow cytometry using FITC-conjugated tarin, affinity with all bone marrow cell populations was observed. Tarin led to a decrease in the percentage of IL7Ra+ cells indicating differentiation into myeloid lineage cells, during hematopoiesis. This result corroborates with the increase in GR1+ cells by tarin. Although tarin decreased IL7Ra+ cells, indicating a decrease in the percentage of lymphoid lineage cells, the ratio between lymphocyte populations changed, presenting an increase in CD3+ cells (T lymphocytes) and a decrease in CD19 + cells (lymphocytes pro B and B). Studies need to be performed to evaluate if tarin acts directly on hematopoietic cells and / or if it has indirect action through interaction with bone marrow stroma. Thus, tarin, the lectin purified from taro, could
be applied as a food additive to boost the immunological status of the
consumer.