Q2 - Immunology Flashcards
Micro biome produces metabolites - like Vit K and B vitamins.
What are the stages of an “IPIC” infection?
Incubation - exposure to onset of 1st symptoms
Prodromal - 1st symptoms - mild
Invasion - further affecting body tissues
Convalescence - Recovery, declining symptoms, death, or period of latency.
Does the “success” of an infection depend more on the # of pathogenic organisms or the compromise of the host’s defenses?
The # of microorganisms.
Put the chain of infection in order from start to finish:
Reservoir
Portal of Exit
Mode of transmission
Portal of entry
Susceptibility of victim.
RPMPS.
What is the difference between direct and indirect transmition?
Pg. 283
Direct = direct contact with infections of another individual such as the skin lesions of impetigo and STIs (Maternal/fetal)
Indirect = vector-borne, vomited, droplets, fecal/oral, etc.
What is the hallmark of infection?
Fever.
Gram-Negative bacteria ______ retain violet dye in gram staining. They have a _______ coat which means they can secrete ________ when destroyed.
Gram-POs bacteria _____ retain violet dye in gram staining.
DO NOT
Lipopolysaccharide coat
Endotoxin
DO
Pyrogenic bacteria release _______ that cause inflammation and produce fever.
Endotoxins when destroyed
You are looking under a microscope and see large microorganisms with thick, rigid cell walls. What do you suspect?
a fungal infection.
You are looking under a microscope and see a microorganisms that has formed a complex of 2 and has NOT stained with the violet dye. What infection do you suspect?
Gram -negative bacteria
_______ grow as multinucleate, branching hyphae. Eg. _______
______ grow as ovoid or spherical single cells. Eg. ______
Molds
Ringworm
Yeasts
Histoplasma/candida.
Why are fungal infections so dangerous?
Because they can adapt to a WIDE range of host environments:
Temp, low O2, and various pH.
The provider has noticed some candida organisms on an analysis of a patient’s skin scraping. Is this normal or abnormal?
In balanced amounts,candida is part of the healthy micro biome in the skin, GI tract, mouth and vagina.
A flatworm is a type of what organism? Trichomonas? Malaria?
Parasite.
Parasite.
What is tissue damage caused by parasites is secondary to?
Release of enzymes that destroy surrounding extracellular matrix and tissues.
classifications of viruses
RNA or DNA
Ss or Ds
Does it use reverse transcriptase or not (all RNA viruses except for flu and HIV
How do most DNA viruses replicate? How do most RNA viruses replicate?
DNA - all except for pox viruses replicate genome in the nucleus where they use the host’s transcriptase enzymes to produce mRNA
RNA - most except for flu and HIV replicate in the cytoplasm and directly make mRNA using viral polymerases.
Vaccination is a type of ________ immunity.
What are some examples of passive immunity?
Active immunity.
Mother to fetus. IVIg
ADAPTive immunity
A a long time
D da B lymphocytes
A antibodies = memory
P particular = specific
T Tc, Th, Treg cells involved
INNATE immunity
Intense - fast
N not specific
N no memory
A acute
T tattletale = APCs, inflamm mediators
E Enlarge (vasodilation), exit (vascular permeability), engulf (macrophages)
Bridge between innate immunity and adaptive immunity?
NK cells
Clonal DIVERSITY begins before birth and continues throughout life. How does it occur?
Each B and T cell develops it’s own specific BCR/TCR which can recognize only 1 antigen. Taken together as a population, the B/T cells can recognize more than 10^16 different antigenic determinants
What is clonal SELECTION
When an antigen is encountered by a particular lymphocyte.
What is clonal EXPANSION?
When a specific antigen is encountered by a particular lymphocyte (clonal selection), many copies of that lymphocyte are generated in order to properly respond to that pathogen.
Where do clonal expansion and clonal selection take place?
In the lymphatic system or 2ndary lymphoid organs.
Where does clonal diversity occur?
In the thymus and bone marrow - or primary lymphoid tissue.
Is a foreign antigen involved in clonal diversity or clonal deletion?
Clonal selection and clonal expansion?
No
Yes
Clonal deletion promotes ________ and prevents _______
Tolerance
Autoimmunity.
What is clonal deletion and where does it occur?
Developing lymphocytes that bind with high affinity to self-antigens are killed or altered so they no longer attack host issues. Estimated up to 90% occurs in the primary lymphoid organ - thymus
A lack of tolerance means?
Inability of the body to recognize self-antigens = autoimmune or hypersensitivity disorders
contrast Humoral Immunity and cell-mediated immunity
Humoral (if you want humor then you have to B funny!) - involves B cells producing antibodies after an exposure to an antigen. These antibodies then conduct the humoral immune response (B-cell presents the antigen via the MHCII to the Th cell. This signals the B cell to differentiate into plasma cells that secrete more antibody specific to the antigen)
Cell-Mediated - Tc, NK cells and phagocytes. Destroys the target cell by reading the antigen presented on the MHCI
Most abundant class of immunoglobulin and most protective activity against infections?
IgG
What immunoglobulin is transported across the placenta?
IgG.
What is the largest Ig and first antibody produced during a response?
IgM.
What Ig functions as part of the BCR antigen receptor on early B cells?
IgD
Which Ig is lowest in concentration and defends against parasites?
IgE.
BCR responsible for______
TCR responsible for ______
Sending messages to mature and make antibodies
Sending messages to activate and differentiate T cells
Which IL is critical in driving further differentiation and proliferation of the B cell?
IL-7
_____produce cytokines that activate macrophages
T-cells
What type of T-cells may be involved in peripheral tolerance?
Tregs. Control and limit the immune response.
Innate resistance is composed of _______ and _________
Natural barriers and the inflammatory response.
Antimicrobial peptides such as _______, ______ and ______ are part of ________ immunity.
Catholicizing, defensins, and collectins
Innate.
Steps of innate immunity
- Tissue damage and cell injury or pathogen invasion.
- Mast cell synthesis, activation of plasma proteins and macrophage activation
- Histamine, cytokines, INF, interleukins and complement clotting factors released
- Vasodilation, increase in capillary permeability, cellular infiltration of phagocytes, thrombosis and stimulation of nerve endings (pain)
Draw pg. 207 (phone picture) to show how the complement system, clotting system and kin in system interact during innate immune response
What is common about the clotting system, complement system and kinin system?
They all contain inactive enzymes (pro enzymes) that are sequentially activated in a cascade.
What are 3 ways the complement pathway can be activated? What is the end result?
1 - classical activated by antibodies
2 - lectin activated by MBL on pathogens
3 - Alternative = activated by bacterial products
Ends with C1 enzyme = C3, =C5 then C9 with puncture ring = membrane attack complex and perforation. Can also initiate phagocytosis and mast cell release of histamine.
Tissue-damage causes initiation of the _______ pathway
Damaged vessel wall causes ignition of the _______
Extrinsic
Intrinsic
T/F: the Kinin system can activate the clotting system and vise versa
TRUE
Kalikrein can activate factor XIIa in the intrinsic to activate factor X, thrombin, fibrinogen, fibrin and then a blood clot.
Activation of factor XIIa interacts with Prekalikrein which cascades to cause histamine-like effects like increased permeability and vasodilation
The plasma protein system involves input from ______ system (______) and the ________ system (_________)
Clotting system (XIIa, Plasmin, Thrombin)
Kinin system (Kalikrein)
Innate inflammatory response is initiated when ____________ or when __________ are recognized by ______ on cells of the innate immune system.
tissue injury occurs
PAMPs
PRRs
T/F: chemokines or cytokines regulate innate or adaptive response by affecting other neighboring cells.
True.
IL __ causes fever
IL ___ helps with healing
IL ____ is anti inflammatory
1
6
10
______ are antiviral cytokines.
IFN - interferons.
Alpha and beta and gamma.
Difference between cytokines and chemokines
Cytokines - IL and IFN help regulate inflammation
Chemokines - induce WBC chemotaxis.
What does histamine do?
H1 and H2?
Rapid constriction of large vessels and dilation of post capillary venues. Retracts the endothelial cells lining the capillaries to increase permeability.
H1 - PROinflammatory in bronchi
H2 - anti inflammatory in stomach mucosa. gastric aciid
What is responsible for attracting neutrophils in the early phase of acute inflammation?
Chemotactic factors released during mast cell degranulation.
Which cell mediators are more important in the LATER stages of inflammation?
Leukotrienes.
Which lymphocytes predominate in early inflammation and remove debris in sterile lesions?
Which defend against parasites and control vascular effects of inflammation?
Which secrete IL4 and associated with allergies and asthma?
Neutrophils.
Eosinophils
Basophils.
What helps minimize the destructive effects of the enzymes released by the dying phagocytes?
Alpha1-antitrypsin.
What does it mean to have a left shift in leukocytosis?
There is an INCREASE in the number of immature cells (bands) as the immune system works to get them out into circulation to fight the pathogen.
A patient it’s granuloma, epithelioid cel and giant cell formation would indicate?
Chronic inflammation.
What is the most favorable outcome of wound healing?
Regeneration of healthy tissue.
Phases of wound healing
Phase 1: hemostasis
Phase 2: inflammation
Phase 3: proliferation and new tissue formation.
Phase 4: remodeling and maturation.
What is different about a neonate’s immune system?
Transiently depressed inflammatory and immune function
Neutrophils are not capable of efficient chemotaxis
Deficient complement system
More susceptible to bacterial infections.
Difference between HIV1 and HIV2
HIV1 - originated in central Africa. More rapid, severe and leads to AIDS.
HIV2 - originated in west Africa - has a longer latency period and lower plasma levels and mortality rates.
Major genes on HIV virus and what they do:
Pol
Env
Tat
Gag
Pol - encodes a wide variety of enzymes
Env - mediates CD4 and chemokines receptor binding while it fuses to the cell.
Tat - elongation of integrated viral DNA.
Gag - promote virus assembly at cell surface and participate in terminal step of viron binding
What type of virus is HIV?
RNA
What are some main enzymes the HIV virus uses and why are they important?
Reverse transcriptase
Integrase
Protease
ART therapy targets these enzymes to break the cycle of viral replication.
HIV test looks for the gp120 and gp41 glycoprotein spikes on the outside of the virus.
Draw pg 294 pic on phone.
A patient on ART stops responding as well as he used to on these medications. This is an (expected/unexpected) finding due to _________
Expected
Rapid replication of HIV RNA/DNA makes for many chances of mutations.
HIV genome codes for structure (gag, Env), viral enzymes like reverse transcriptase, Integrase and protease (pol, int, pro) and infectivity, viral assembly and release (tat, tax, Rex, rev, Vif, VPu and vpr)
