Acquired Immunodeficiencies

Congenital Immunodeficiencies

Chemotherapy

HIV Vaccines

The Stages of HIV Infection

The Infectiveness and Pathogenicity of HIV

The Structure of HIV

The Origin of AIDS

Acquired Immunodeficiency Syndrome (AIDS)

Acquired Immunodeficiencies

Congenital Immunodeficiencies

Immunodeficiencies

Figure 3. Steps in recombinant DNA, gene cloning, and product retrieval.

Plan:

The absence of a sufficient immune response is called an immunodeficiency, which can be either congenital or acquired.

Some people are born with a defective immune system. Defects in, or the absence of, a number of inherited genes can result in congenital immunodeficiencies. For example, individuals with a certain recessive trait, DiGeorge's syndrome, do not have a thymus gland and therefore lack cell-mediated immunity.

A variety of drugs, cancers, or infectious agents can result in acquired immunodeficiencies. For example, Hodgkin's disease (a type of cancer) lowers the cell-mediated response. Many viruses are capable of infecting and killing lymphocytes, lowering the immune response. Removal of the spleen decreases humoral immunity. Table 1 summarizes several of the better known immune deficiency conditions.

Дата добавления: 2014-01-11