Immunology and Cell Biology

Veterinary Immunology and Immunopathology

All living organisms are continuously exposed to substances that are capable of causing them harm. Most organisms protect themselves against such substances in more than one way --- with physical barriers, for example, or with chemicals that repel or kill invaders. Animals with backbones, called vertebrates, have these types of general protective mechanisms, but they also have a more advanced protective system called the immune system. The immune system is a complex network of organs containing cells that recognize foreign substances in the body and destroy them. It protects vertebrates against pathogens, or infectious agents, such as viruses, bacteria, fungi, and other parasites. The human immune system is the most complex .Although there are many potentially harmful pathogens, no pathogen can invade or attack all organisms because a pathogen's ability to cause harm requires a susceptible victim, and not all organisms are susceptible to the same pathogens. For instance, the virus that causes AIDS in humans does not infect animals such as dogs, cats, and mice. Similarly, humans are not susceptible to the viruses that cause canine distemper, feline leukemia, and mouse pox.

Immunopathology is a branch of biomedical science concerned with immune responses to disease, with immunodeficiency diseases, and with diseases caused by immune mechanisms.  It includes the study of the pathology of an organism, organ system, or disease with respect to the immune system, immunity, and immune responses. The immunopathalogical reaction is caused by release of toxins and the apoptosis of infected cell.