HLA-C and parathyroid gland adenoma: However, searching the literature several authors reported on alternative experimental strategies to restore parathyroid tissue without the need for immunosuppressive therapy, e.g. by using cultured cells [8, 19], cryopreserved tissue [20, 21] or magnetic microspheres depletion of major histocompatibility complex (MHC) of cells from parathyroid adenoma [8].