CD34+CD31+ immature myeloid cells (IMC) as an inhibitor cell on the production of antimicrobial peptide: III. Translational studies of glycyrrhizin in humanized NOD-SCID IL-2rγ-/- mice (NOD-SCID mice) (89.30)

Abstract

Abstract In the accompanying paper II, glycyrrhizin (GL) is shown to be inhibitory on the CD34+CD31+ IMC-mediated suppression of HBD-1 production by normal human epidermal keratinocytes (NHEK). In this study, the inhibitory effect of GL on CD34+CD31+ IMC-mediated suppression in HBD-1 production by NHEK was tested in human immune system mice (HIS mice) (X-irradiated NOD-SCID mice inoculated i.d. with NHEK and CD34+CD31+ IMC). Two days after the cell inoculation, inoculation site skin tissues were biopsied (8-mm diameter) from HIS mice treated with or without GL (Minophagen Pharmaceutical Co., Ltd., Tokyo, Japan) 6 and 24 hrs after the cell inoculation. Five biopsied tissue samples were homogenized together on ice in PBS. The concentrations of HBD-2 in the homogenates were measured by ELISA. In the results, 4.9 μg/ml of HBD-2 was detected in skin homogenates derived from NOD-SCID mice inoculated with NHEK, while HBD-2 was not detected in skin homogenates from HIS mice. When HIS mice were treated with 10 mg/kg of GL, HBD-2 was detected in IMC-inoculation site tissues of these mice. The amount of HBD-2 detected in this homogenate was corresponded to that detected in tissues of NOD-SCID mice inoculated with NHEK alone. These results indicate that GL improves the suppressed HBD-2 production in HIS mice. This study was supported by SHC #8610.