By Western blot analysis using an antibody against guinea pig phospholipase B (PLB), Maury et al. (2002) detected a 97-kD polypeptide in the soluble and membrane fractions of human epidermis that was enriched in the soluble fraction. Consistent with these results, they found that PLB activity was greatest in the soluble fraction.
Trypsin had no effect on the molecular mass or enzymatic activity, suggesting that the protein they detected was already in an active form.
Immunolocalization experiments revealed that PLB is expressed in the entire human epidermis with an accumulation in the dermoepidermis junction. In situ hybridization also indicated expression in the entire epidermis.