acquired immunodeficiency disorders. Flashcards
the immune system is coordinated by four powerful immune modulators what are they /
hormonal glucocorticoids
cytokine system - interleukins and interferons
network connectivity - idiotypic and antiidiotypic response
antigen response
what is the affect of glucocorticoids in the immune system ?
acton on immune cell trafficking , cytokine synthesis
administration of corticosteroid have what immune trafficking changes changes ?
changes in circulating leukocyte population
lymphocytopenia = maximal for 4-6 hours and return to normal by 24 hours
T cells are affected more than b cells
TCD4 cells are more affected the TCD8 cells
monocytopenia
neutrophiliia = due to reduction of cells and release of mature stored cells in the bone marrow
administration of corticosteroids have what affect on t cell activation and cell maturation
(T cell activation and proliferation inhibited
not responsive to IL-1 AND therefore unable to synthesise IL-2
inhibit the early stage of b cell maturation by blocking monocytes and t cells )
have lift affect on mature b cells
inhibit production of IL-1 and TNF by monocytes
do not block the affects of cytokines on phagocytosis = they can actually promote it
binding of interferon gamma and expression of HLA-DR molecules and FC receptors may be increased in low doses
what are the corticosteroid affect on cytokines ?
inhibit the synthesis of cytokines but NOT THEIR FUNCTION
reduce IL-1, IL-2 , 4,6,10
TNF-A , IFN-Y
= major consequence of t cells activation inhibition
what is the effects of cyclophosphamide on the immune system ?
affects lymphocyte numbers and PMN cells remain unchanged
low dose ORAL THERAPY affect on cell mediated response
BOLUS intermittent treatment effect on antibody production
(CYTOTOXIC - their FUNCTION S AFFECTED )
cyclophsophamide is used to treat what type of disease
autoantibody disease and allograft ejection
what is the effects of azathioprine on the immune system ?
affects the dna synthesis
cyclophosphamide is CYTOTOXIC AZOTHRIPINE IS CYTOSTATIC
it is only active on dividing cells
modest reduction in T AND B CELLS
NK cell activity surpassed
humeral immunity and delayed hypersensitivity are not altered
what is the effects of methotrexate on the immune system ?
structural analogue of folic acid and block folic acid dependant dna synthesis
(immunoglobulin synthesis is reduced after prolonged treatment - after three months )
inhibitor of PMN = anti-inflammatory effects
inhibitory effect of arachidonic acid = anti-inflammatory effects
reduction in CRP AND ESR -
what is the immune effects of cyclosporin and tacrolimus fk506 and rapamycin ?
three drugs has effect on T cell singling and T cell function
they bind to cytoplasmic proteins called immunophillins = which are involved intending signals from cell surface to cell nucleus
rapamycin blocks T cell proliferation
what are the main drugs which causes immunodeficiency ?
corticosteroids cyclophosphamide azathioprine methotrexate cyclosporin tacrolimus rapamycin
what are other causes for immunodeficiency from the environmental factors ?
malnutrition
infection -AIDS
nutrition does not affects the immune reaction to all infections equally what are some infections where nutrition is important ?
influenza and HIV
which tissues are most affected by malnutrition ?
lymphoid tissues - lymphoid atrophy is an indication for malnutrition
extend of damage depends on the cell proliferation , amount and rate of protein synthesis ,and role of individual nutrients in critical metabolic pathways
which lymphoid tissue suffers great in malnutrition and describe the changes from normal ?
the thymus
the lobular structure is more ill defined and loos of corticomedually demarcation, fewer lymphoid cells
periarteriolar areas of the spleen
paracortical section of the lymph nodes
severe and moderate malnutrition can lead to what
reduction in cell mediated immunity - reduce number of CD4 th
reduction in IgA secreted to vaccine
protein energy malnutrition phagocytosis is affected
opsonisation decreases - c3,c5 and factor b
Il-2 and TNF decreased
production lysozyme slightly decreased
what does zinc deficiency have to do with immunodeficiency ?
delayed cutaneous hypersensitivity is affected
lower CD4 AND CD8 ratio
T cell dysfunction
REDUCTIONIS SERUM THYMULIN
lymphoid atrophy
how does vit b and folate deficiency affected the immune system
cell mediated immunity reduced
lymphocyte proliferation
impair antibody production
how does iron deficiency affect immune system ?
iron dependant enzyme crucial role in lymphocyte and phagocyte
decreased lymphocyte response to mitogens and antigens
impaired NKactivity
how does selenium and copper affect the immune system ?
cosackie recovered from selenium deficit mice heightened the myocardial damage
how does vit a have an effect on the immune system ?
deficiency alters epithelial structures = metaplasia
what are the two main variants of HIV
HIV -1 AND HIV 2
HIV 2 is endemic in west africa and less pathogenic
how does hiv spread ?
vaginal and anal sex
share of blood
through the placenta
what is the receptor site for the HIV virus ?
the CD4 protein - in cd4 t cells and cells of the monocyte and macrophage lineage
what is the pathophysiology of hiv immune dysfunction
infected C4 cells bind to unaffected cells by gp120-cd4 linkages
making them vunreble to antibody mediates cell mediated cytotoxicity
infected cells killed by gp120 specific cytotoxic t cells
hiv act as super antigens - resulting in exhaustive depletion of cells
T cell apoptosis and viral budding leading to lysis
what is the immune dysfunction in HIV characterised by
T cells depletion of cd4 th cells decreased proliferation to antigens , mitogens , alloantigens anti cd3 antibody decreased il-2 production
increase in ACTIVATES AND UNRESPONSIVE CD8 T CELLS
b cells polyclonal immature b cell activation increased IgG , A , D , E decreased IgG2 , 4 increased immune complexes increase in autoantibodies
nk cells
decrease defective killing effect
antigen presenting cells
decreased IL-1 and INFa
decreased intracellular killing
decreased antigen presenting
what is the clinical picture of AIDS
primary glandular fever malaise muscle pain swollen lymph nodes sore throat rashes
later infection fever night sweat diarrhea weight loss ORAL CANDIASIS SHINGLES recurrent angiogenital herpes = oppurtnustic inactions
pneumocytis crania
mycobacterium tuberculosis
protozoa - cryptosporidium microsporida
salmonella
campylobacter
diagnosis off HIV
2-6 weeks detect by ELIZA - enzyme linked immunoassays detect hiv antibodies
those infected with HIV DEVELOP AID in how many years ?
50 percent those affected develop aids in 9-10 years
what is a complication of AIDS ?
kaposi’s sarcoma = multifocal tumor of endothelial cells
b cell lymphoma
neurological complication - direct effect from opportunistic infection or lymphoma
AIDS elated dementia
toxoplasmosis - cyst in therein
cytomegalovirus - inflammation of brain and retina and spinal cord
