Aim: To analyse biological properties of Mycobacterium tuberculosis polypeptide antigen(Mtb-Ag) that could stimulate the proliferation of human gammadeltaT cells.
Methods: Mtb secretory proteins and Mtb-Ag treated via dialysis or with pronase were used to stimulate human PBMCs. After being cultured for 10 days, the phenotype of responsive cells was analysed by flow cytometry.
Results: The proliferation stimulating activity to human gammadeltaT cells of dialysed Mtb-Ag did not decrease remarkably, whereas that of the pronase-treated Mtb-Ag reduced significantly. Moreover, the proliferative stimulating activity to gammadeltaT cells of Mtb-Ag was notably higher than Mtb secretory protein.
Conclusion: The component in Mtb-Ag that can stimulate the proliferation of human gammadeltaT cells is a non-secretory and protase-sensitive polypeptides with M(r) over 10 000.