immunity Flashcards
hypersensitivity reactions
- inappropriate response to antigen
- occurs immediately or within minutes to hours
- classified by pathogenesis
classified pathogenesis
type 1
- IgE mediated
type 2
- cytotoxic reactions
type 3
- immune complex
type 4
- cellular/ delayed
immunoglobulin functions: igG
- defense against bacteria
- most numerous
- within the blood and lymph
- ability to cross the placenta
immunoglobulin functions: igM
- defense against blood-borne infections
- produces additional igG
- first responder
immunoglobulin functions: igA
located within mucous membranes, tears, saliva, mucous, and colostrum
- nonspecific- protect against a wide variety
- gatekeeper- the line of defense and portals of entry
immunoglobulin functions: igE
- initiates inflammation to trigger allergic reactions (contact allergies)
- support mucous membranes and skin
immunoglobulin functions: igD
- rarest immunoglobulin
- monitors other immunoglobulins
- stop autoimmune from occurring
- regulatory
type 1 hypersensitivty
immediate reaction
- had to have been previously exposed (sensitization)
1st exposure: IgE: antibodies are made and attach to mast cells through the body
2nd exposure: antigen causes IgE to trigger T cells and histamine
type 11 hypersensitivity
cytotoxic and cytolytic reaction
- igG and igM antibodies bind with antigen on cell surface
- cell destruction occurs
- resulting in: Lysis, phagocytosis
cell destruction
complement-mediated cell lysis
antibody-dependent cell-mediated cytotoxicity
type 2 hypersensitivity targets
rbcs, wbcs, plts
- abo incompatibilities
- rh incompatibilities
type 3 hypersensitivity
- immune complex reactions: antigen-antibody complexes
- ineffectively removed by phagocytosis
- autoimmune diseases
- sites: kidneys, skin, joints, blood vessels. and lungs
type 4 hypersensitivty
- cell-mediated or delayed hyperensitivty reactions. mediated by t cells as opposed to antibodies
- occurs in two phases
- sensitization phase
- effector phase
type 3 examples
examples: systemic lupus, glomerulonephritis, rheumatoid arthritis
type 4 examples
contact dermatitis, tubercule and skin testing and transplant rejections
sensitization phase
contact with antigen stimulates memory cells
effector phase
subsequent exposure
release of cytokines
ends in phagocytosis
allogeneic
transplanted tissue from the same species but not identical
syngenic
transplanted tissue its from identical tiwn
autologous
transplanted tissue is from the host
xenogenic
transplanted tissue is from another species
hyperacute tissue rejections
- immediately- 3 days post-transplant
- host has antibodies against donor tissue
acute tissue rejection
- 4 days- 3 months post-transplant
- most common and treatable
- result from cell destruction
chronic tissue rejection
- 4 months- years after transplant
- antibody-antigen mediated
classification of transplant rejections
- host-versus-graft rejection: host rejecting transplant
- graft-versus-host rejection- transplant tissue attacks person- only for bone marrow
autoimmunity
- normal defenses become self-destructive
- 80 diseases
- treatment focuses on symptom management
- common to have multiple
- women after more than men
- exacerbations
- remissions
lupus types
- neonatal
- discoid
- drug induced systemic lupus
- systemic lupus erythematosus
- most common
- chronic, progressive, inflammatory
- multisystem disorder
joints
- polyarthritis: joint pain in 5 joints
- arthralgia: joint stiffness
skin
- butterfly rash
- photosensitivity
- oral ulcers
- alopecia
kidneys
- proteinuria- protein in urine
- glomerulonephritis
lungs
pleurisy- sever inflammtion of pleural linning
heart
carditis- inflammation of sac around heart
blood vessels
Raynaud’s phenomenon
nervous system
- depression
- mood changes
- seizures
diagnosis of sle
- no single test
- scored based on 22 criteria
lab test
- antinuclear antibody screen (ANA)
- erythrocyte sedimentation rate (ESR)
- c- reactive protein (CRP)
treatment of SLE
- symptom management
- stress reduction, exercise, sleep
medical
- nonsteroidal anti-inflammatories: tynol
- corticosteroids: inflammation
- immunosuppressants
primary immunodeficiencies
- defect within the immune system
- genetic and or congenital abnormalities
secondary immunodeficiencies
- underlying disease
- infection
- liver diseases
- suppressing factors
- medications
- malnutrition
opportunistic infections
infections from pathogens that typically wouldn’t cause disease
human immunodeficiency virus
- chronic infection: no longer characterized as life-ending illness
- sometimes progressive immune disorder
acquired immunodeficiency syndrome
- late phase of HIV infection
- no cure
HIV-1
worldwide
HIV-2
Africa
HIV modes of transmission
person to person
needs a portal entry
person to person
blood semen vaginal secretions breast milk body fluids containing blood
portal of entry
tear in mucous membrane
non-intact skin
access to bloodstream or lymphatic tissue
HIV patho
- hiv viral particle taken into the human cell–> covering destroyed to expose viral RNA
- reserve transcriptase (enzyme) forces the human cell to produce new DNA from viral; RNA
- New DNA than spreads via the lymphoid system
- CDA + t-lymphocytes begin to function abnormally
- impairment of the immune system results
HIV progression
- initial infection –> clinical latency stage (symtom free)
- if infection remains untreated—> CD4+ Tlymphocytes begin to decrease
how long does symtom free period vary
8-12 years
early symtomatic stage= signs of weakening immune system
HIV diagnosis
- enzyme- linked immunosorbent assay
- nucleic acid test
aids diagnosis
- CD4+ t lyphocyte count below 200
- opportunistic infections and diseases
management of HIV
- no cure
- prevent or delay development of opportunistic disease
prevntion of HIV
- pre-exposure prophlaxis
- safe sex practices