Immunosuppression Flashcards
What is immunity?
Complex system for controlling body integrity.
How is humoral and cell-mediated immunity different?
The major difference between humoral and cell-mediated immunity is that humoral immunity produces antigen-specific antibodies, whereas cell-mediated immunity does not. T lymphocytes, on the other hand, kill infected cells by triggering apoptosis.
How is innate and specific immunity different?
The innate immune response is activated by chemical properties of the antigen. Adaptive immunity refers to antigen-specific immune response. The adaptive immune response is more complex than the innate. The antigen first must be processed and recognized.
What are antibodies?
An antibody, also known as an immunoglobulin, is a large, Y-shaped protein used by the immune system to identify and neutralize foreign objects such as pathogenic bacteria and viruses. The antibody recognizes a unique molecule of the pathogen, called an antigen.
What are cytokines?
Cytokines are a broad and loose category of small proteins important in cell signaling. Cytokines are peptides and cannot cross the lipid bilayer of cells to enter the cytoplasm. Cytokines have been shown to be involved in autocrine, paracrine and endocrine signaling as immunomodulating agents.
What are complement molecules?
The complement system, also known as complement cascade, is a part of the immune system that enhances the ability of antibodies and phagocytic cells to clear microbes and damaged cells from an organism, promote inflammation, and attack the pathogen’s cell membrane.
What are the functions of the immune system?
prevent and fight infection
eliminate tumours
What are the main reasons for immune dysfunction?
Hypersensitivity (vigorous reactions to substances that are not harmful)
Autoimmunity (immune system attacks own cells)
Immune deficiency (autoimmunity can be the first manifestation of immune deficiency)
What is reduced immune status ?
Immunosuppression
Immunocompromised
Immunodeficiency
Classified as either congenital or acquired.
What is HIV?
Human Retrovirus, Lentivirus family
Gp120 binds to CD4 receptor
long latency
profound effect on immune function
What is AIDS?
Acquired Immune Deficiency Syndrome
What is the clinical spectrum of HIV infection?
Primary infection (seroconversion illness/infectious mononucleosis-like)
Asymptomatic
Progressive generalised lymphadenopathy
AIDS-Related Complex
AIDS
What is AIDS-Related Complex?
Low grade pyrexia
Persistent lympadenopathy
Night sweats
Weight loss
Diarrhoea
Oral Candidosis
What is AIDS?
Disease
Suggestive of severe cell mediated immune defect
Occurs in patients in whom there are no other known cause of immunosuppression
A CD4 T cell count of less than 200 x 106 cells per litre
Being HIV positive and suffering infections/cancers typical of the immunosuppressed.
What are the general features of AIDS?
1981 Recognised
Wide geographic variation
High risk groups
