Hbd 1

HBD-1 kits were purchased from PeproTech (Rocky Hill, NJ, USA). HBD-1, MBD-1, anti-HBD-1, and anti-MBD-1 antibodies were purchased from Alpha Diagnostic International (San Antonio, TX, USA). Lineage cell depletion kits were purchased from Miltenyi Biotec (Auburn, CA, USA). FITC-conjugated anti-CD34 mAb and PE-conjugated anti-CD31 mAb were purchased from BD Biosciences (Franklin Lakes, NJ, USA) and BioLegend (San Diego, CA, USA), respectively. Recombinant (r) CCL2 and rIL-10 were obtained from PeproTech, and mAbs directed against CCL2 and IL-10 were purchased from BioLegend. Adult normal human epidermal keratinocytes (NHEK) were obtained from Lonza (Walkersville, MD, USA) and propagated in a serum-free keratinocyte growth medium (KMG-2, Lonza) at 37°C. NHEK that underwent a second passage with KMG-2 were stored in liquid nitrogen. NHEK grown from the stored cells (the third passage) were used in this study. RPMI-1640 medium supplemented with 10% FBS, 2 mM L-glutamine, and antibiotics (100 U/ml penicillin and 100 µg/ml streptomycin) was used as culture media for lineage⁻CD34⁺ cells. A Protease Inhibitor Cocktail was purchased from Sigma-Aldrich (St. Louis, MO, USA).

Levels of HDPs LL-37 (ng/mL), HBD-1 (pg/mL), and HD-5 (pg/mL) were measured in plasma and stool extracts by using enzyme-linked immunosorbent assay (ELISA) kits (LL37, Hycult Biotech; HBD-1, Alpha Diagnostic International; HD-5, Elabscience) according to manufacturers’ instructions.