Trinitrophenol (TNP) is an important hapten often used for immunological research. Haptens are small molecules that can elicit an immune response when they are attached to a carrier molecule such as a protein. A TNP-protein conjugate can be injected into an animal model, such as a mouse, so that their immune system can produce anti-TNP antibodies. By measuring changes in the levels of anti-TNP IgG in these animals, scientists can evaluate how pharmacologic or genetic manipulations impact the protective role of IgG in the immune response. Signosis offers an ELISA kit to measure mouse anti-TNP IgG.