Hypersensitivity reactions are exaggerated or inappropriate immune responses to antigens, including toxins. There are four types of hypersensitivity reactions:
1. Type I: Immediate hypersensitivity, often mediated by IgE antibodies, and can lead to conditions like anaphylaxis. 2. Type II: Antibody-dependent cytotoxicity, where antibodies target cells for destruction, such as in hemolytic anemia. 3. Type III: Immune complex-mediated reactions, where antibodies form complexes with antigens, leading to inflammation, as seen in glomerulonephritis. 4. Type IV: Delayed-type hypersensitivity, mediated by T-cells, and can result in contact dermatitis or organ-specific damage.
Understanding these reactions helps toxicologists identify and manage immune-mediated damage associated with various toxins.