Penicillium Notatum IgG Unit Converter

Penicillium notatum IgG is a blood test that measures immunoglobulin G (IgG) antibodies specific to the mold Penicillium chrysogenum, formerly known as Penicillium notatum. These antibodies reflect an immune response to inhaled or environmental mold proteins.

Penicillium chrysogenum is one of the most common indoor molds, frequently found in damp or water-damaged buildings, on salted foods, and in poorly ventilated spaces. Its airborne spores contain allergenic proteins (notably Pen ch 13 and Pen ch 18) that can trigger an immune response when inhaled.

Unlike IgE antibodies, which drive immediate allergic reactions, IgG antibodies indicate a delayed immune response and are used primarily to evaluate for hypersensitivity pneumonitis. An elevated level confirms exposure and immunological sensitization but does not by itself diagnose disease.

IgG antibodies are produced by plasma cells, which are mature B lymphocytes originating in the bone marrow. When inhaled Penicillium spore proteins are recognized as foreign, B cells in the lymph nodes and spleen differentiate into plasma cells that secrete antigen-specific IgG into the bloodstream.