Immunity Flashcards
What does infection or colonization mean ?
It refers to microorganisms multiplying in or on the host.
- bacteria are staking their claim and growing their settlement
What is the microbiome?
This refers to all the microorganisms that live within the body. Its like the whole ecosystem of microbes living within the environment of the body.
What benefits do bacteria of the microbiome offer?
They protect against pathogens by inhibiting pathogen attachment to the epithelium, competing with pathogens for food supply and have unique antibacterial properties that can limit/inhibit pathogenic colonization.
Normal flora also strengthens the body’s adaptive immune system.
What do normal flora of the body produce?`
Enzymes to help with digestion, usable metabolites like vitamin K and B and antibacterial factors to prevent colonization
Are there more microbial genes or human genes within our body.
There are more microbial genes- a hundred times more in fact than our own human genes.
The microbial genes react and engage and turn on/off based on what we do , while our genes turn on/off in response to what our microbes do
Is our microbiome constant in terms of the kinds of amount of microbes that harbor and colonize?
No, microbiomes are always changing.
They can change in response to our diet, medications, health status, with puberty or pregnancy.
And in our early days, whether we were delivered vaginally or through Cesarean section, or whether we were breast fed or formula fed- these all make a difference in the forms and amount of bacteria that colonize.
What effect can a prolonged use of antibiotics have on the normal flora ?
How long can this take to restore?
It can kill the beneficial bacteria within our biome.
It could take up to a year to restore the colonies of normal flora.
What are interventions that can restore a depleted or weakened microbiome?
Probiotics encourage microbe growth
Fecal microbial transplant can introduce someone’s healthy microbe infested fecal matter into the intestine of someone’s depleted biome.
What is the difference between innate and adaptive immunity?
Innate immunity (also called natural or native) are natural defenses of the body that we are born with and are always present- they do not distinguish between microbes- this includes skin, mucous membranes, stomach acidity, cilia lining the respiratory tract, sweat, coughing, vomiting.
Adaptive immunity are defenses that we develop as a result of exposure to a pathogen- this includes antibodies, memory cells and other processes that enable us immune to a certain pathogen.
Is natural immunity specific or nonspecific?
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Nonspecific. There is no targeted, specific response towards the antigen
Is adaptive immunity specific or nonspecific?
Specific - there is a targeted response to the antigen (foreign agent)
What is the first immune response to an injury?
The inflammatory response, which involves 2 stages: the vascular stage and the cellular stage
What are some manifestations of the inflammatory response in a patient?
Redness, swelling, heat, pain and loss of function
Vascular stage of inflammatory response involves ?
The vasodilation of arterioles supplying the area- this causes an increase in blood flow. Histamine is also released which increases the permeability of the vessels, allowing protein rich fluid to pour into the area of injury.
Cellular stage of inflammatory response involves
Leukocytes, such as neutrophils, being delivered to the site of injury and engulfing and disposing of the microbe/foreign agent. Exudate composed of fluid, cells, and inflammatory byproducts is released from the wound. The injured area begins to regenerate and heal.
What are the two types of adaptive immunity?
Cell mediated
Humoral
Humoral adaptive immunity involves ………..
antibodies responding to antigens
Cell Mediated Immunity refers to…………….
Immune responses in which targets are attacked directly by immune system cells- specifically Cytolytic T cells and Macrophages
Name different types of immune system cells
B Cells, cytolytic T cells, helper T cells, macrophages and dendritic cells
Neutrophils and basophils and eosinophils
B lymphocytes produce what ?
antibodies
Cytolytic T cells do what ?
What are other names for these cells ?
Attack and kill target cells directly
Other names include cytotoxic T cells and CD8 cells
Discuss the functions of helper T cells ?
Helper T Cells aid in the production of antibodies by B cells, help activate cytolytic T cells, and release factors that promote type IV sensitivity reactions (DTH delayed type hypersensitivity reactions)
These are the cells that HIV targets
Macrophages
Principal role of phagocytosis. In adaptive immunity (specific acquired), they are required for the activation of helper T cells and cytolytic T cells and so macrophages are referred to as antigen presenting cells (APCs); they also phagocytize cells tagged with antibodies and are the final mediators of DTH (Delayed Type hypersensitivity reaction)
They have important roles in innate immunity, adaptive immunity and inflammation.
Macrophages are the __________________ of the body. They are present in all _______________
Principal scavengers…..organs and tissues
Dendritic Cells;
Antigen presenting cells
Neutrophils
They phagoycytize bacteria and other foreign particles. They devour cells marked with the immunoglobulin G (IgG class). They are major contributors to inflammation and important effectors in humoral immunity.
Mast Cells and Basophils
Mediate hypersensitivity reactions - they release histamine, heparin and other compounds that cause the symptoms of immediate hypersensitivity.
Eosinophils
Attack and destroy foreign particles that have been coated with antibodies of the immunoglobulin E (IgE) class.
Antibodies are also called
immunoglobulins and gamma globulins
Antibodies greatest ability is …………
Recognizing and binding to specific antigens
What are the five classes of antibodies ?
IgG, IgM, IgE, IgD, IgA
Difference between active and passive immunity
Active immunity develops within the body as a result of exposure to antigens from an infection or from administration of a vaccine or toxoid. There is a production of antibodies; while this takes weeks and months to develop the effects are long lasting.
Passive immunity occurs when preformed antibodies are transferred into a person’s body, such as through breast milk. While the effect is immediate, the protection exists only as long as the antibodies remain in the body.
What types of antibody would be elevated when in the first stages of an acute illness?
IgM are the first responders. Their serum levels would be elevated during the acute phase and then fall
IgG antibody would have elevated levels when?
During the acute phase and even after the acute phase levels would be elevated
Antibodies are produced upon ………….
exposure to an antigen
What is an antigen?
A molecule that induces specific immune responses and as a result becomes the target of those response.
What are cytokines ?
These are small proteins that aid cell signaling.
Difference between active and passive immunity.
Active immunity- your immune system creates it own immune response. Example- contracting disease or being injected with vaccine
Passive Immunity- your immune system does not create the immune response. Example- receiving antibodies through injection or breast milk
Difference between primary and secondary immune response…
Primary immune response involves the production of antibodies. It involves encountering a disease/pathogen for the first time. Plasma antibody levels respond within 1-3 weeks
Secondary immune response is much faster response and involves B memory cells that respond to a “remembered pathogen”. The plasma antibody levels respond within days
What do booster shots do?
Booster shots cause a secondary immune response that raises the plasma antibody levels to prepare for an encounter with the disease.
Antibiotics kill bacteria by targeting
cell wall synthesis
protein synthesis
nucleic acid synthesis
bacterial metabolism
What is selective toxicity?
It is a measure of the antibiotic ability to injure target cell/microbe without injuring others. This is an important consideration to be made?
What is crucial in effective antibiotic therapy?
The identification of the organism along with the susceptibility of that microbe to the antibiotic
Amoxicillin - describe it
It is a beta lactam antibiotic, a penicillin. Effective against a wide range of gram positive staph, strep and pneumococcal microbes, including syphillis and Lyme disease
It works by altering the synthesis of the cell wall
Side Effects include Gi upset and diarrhea
Serious SE: Allergy with anyphalytic reactions (fever, rash, wheezing)
What are major mechanisms of resistance that a microbe can use to resist antibiotics ?
They can synthesize drug metabolizing enzymes, have structural changes in one of its target sites, synthesize compounds that alters/defeats antibiotic action
What is acquired resistance?
Microbes that become resistant or have decreased susceptibility to an antibiotic
Antibiotics select for those microbes that are ……………..
most resistant to it. This means that those which are not susceptible to the antibiotic can colonize further and replicate.
Truvada
Functional Class: Antiretroviral, nucleoside reverse transcriptase inhibitor (NRTI)
Indications: Used as part of antiretroviral therapy (ART )in HIV infection, and for prophylaxis if HIV negative (PEP and PrEP)
MOA: inhibits the activity of the HIV-1 reverse transcriptase (RT) by competing with a natural substrate and by being incorporated into nascent viral DNA which results in chain termination.
SE: Nausea, vomiting, diarrhea, headache, dizziness, trouble sleeping, back pain, or change in the color of skin on your palms or soles of the feet may occur. Fat redistribution.
Serious: Guillain-Barre Syndrome
Nursing considerations: Patients already infected with HIV should only take Truvada with other HIV meds. Patient support necessary for successful ongoing drug therapy.
