Acquired immune deficiency syndrome (AIDS) that is caused by the retrovirus HIV.
Autoimmune diseases result from a hyperactive immune system attacking normal tissues – Rheumatoid arthritis, diabetes mellitus type 1 and lupus erythematosus.
Antigens (non-self molecules) elicit an immune response
LAYERED DEFENSE Components of the immune system Found only in jawed vertebrates Found in nearly all forms of life Exposure leads to immunological memory No immunological memory Cell-mediated and humoral components Cell-mediated and humoral components Lag time between exposure and maximal response Exposure leads to immediate maximal response Pathogen and antigen specific response Response is non-specific Adaptive immune system Innate immune system
Particularly important was the work of Paul Ehrlich, who proposed the side-chain theory to explain the specificity of the antigen-antibody reaction; his contributions to the understanding of humoral immunity were recognized by the award of a Nobel Prize in 1908, which was jointly awarded to the founder of cellular immunology, Elie Metchnikoff.
Skin – so long as it is intact – acts as a mechanical barrier, preventing organisms reaching the tissue beneath.
Mucous membranes – like skin, mucous membranes also act as a mechanical barrier, protecting the deeper tissues. Some of the secretions (saliva, nasal mucus, and tears) contain enzymes (lysozyme) which can rapidly kill an invading organism.
It is now known that both the lymphocytes which go to the defense themselves (T lymphocytes) and those which produce antibodies (B lymphocytes) are able to ‘remember’ an invader, sometimes for a number of years after the first contact.
These memory cells thus recognize the invader when it enters the body the next time.
This secondary immune response takes place more rapidly than the primary response.
The system is already prepared, thus producing a more extensive response, as well.
Controller T cells include – Helper T cells and Suppressor T cells.
These controller cells influence the activity of other T cells.
These controller cells influence the activity of other T cells, as well as the other category of lymphocytes, called B lymphocytes.
These controls are very necessary.
It is essential that unwanted organisms should be destroyed and removed without any damage to the body.
Themectomy TT given 1. Thymosin fraction V (Calf thymus) 2. Synthetic polypeptides Thymus
Ontogeny of Immune System Fetus T cells Functions at 7- 1/2 wks Thymus functions at 12 wks B cells Functions at 13 wks IgM First to develop. Rises in intrauterine infection Reaches adult levels by 1 yr IgG Develops at 4 years IgA At adolescence
Diseases due to Immunologic deficiency Primary Secondary
AIDS Acquired immunodeficiency syndrome Pathophysiology Clinical diagnosis Treatment Prevention HIV, the virus that causes AIDS, is shown budding out of a human immune cell.
HIV Treating HIV infected woman during pregnancy Natural history of HIV infection Transmission Signs and symptoms of AIDS in new born How does pediatric AIDS differ from adult AIDS Management & Specific retroviral therapies AZT (3’ Azido, 2’ 3’ deoxythymdine) DDI (2’ 3’ Dideoxyinosine) Immunotherapy (Hyposensitization)