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Introduction to the immune system
MHC class I and MHC class II molecules
B-cell activation and differentiation
Cell-mediated immunity of CD4 cells
Cell-mediated immunity of natural killer and CD8 cells
Somatic hypermutation and affinity maturation
Contracting the immune response and peripheral tolerance
B- and T-cell memory
Anergy, exhaustion, and clonal deletion
Type I hypersensitivity
Type II hypersensitivity
Type III hypersensitivity
Type IV hypersensitivity
Innate immune system
0 / 24 complete
0 / 6 complete
Killed (Inactivated) Fractional Protein Vaccines
Killed (Inactivated) Whole Vaccines
Live Attenuated Vaccines
vaccines p. 141
unvaccinated children p. 183
vaccine for p. 137
vaccine p. 177
vaccine p. 140
unvaccinated p. 183
vaccine p. 136
Bordetella pertussis p. , 141
diphtheria p. 137
encapsulated bacteria p. 125
Haemophilus influenzae p. , 140, 177
Poliovirus p. 164
rabies p. NaN
rotavirus p. 164
Salmonella typhi p. , 142
tetanus p. 136
toxoids as p. 129
vaccine p. 108
When you get an infection, you develop adaptive immunity.
In other words, you generate memory T and B cells, so that if you encounter the same antigen again, they can quickly replicate and respond.
Most of the time we think of immunologic memory developing after natural infection. But memory T and B cells also develop after vaccination.
Vaccination is the process of generating a protective adaptive immune responses against microbes by exposure to nonpathogenic forms or components of microbes.
That’s the key - getting long term active protection to a harmful microbe, from something that’s not harmful.
Vaccination also helps up to establish herd immunity.
Herd immunity is the concept that if enough people in the population - or herd - are vaccinated the entire population, even those who are unvaccinated, develop a higher resistance to that infection.
The amount of people within a herd that need to be vaccinated to maintain herd immune status differs from pathogen to pathogen.
When too few people in a herd are vaccinated, there are more people in the population that are able to get the illness and spread it.
Vaccination is an active process of developing immunity.
This is different from passive immunity which is where a person gets antibodies that are made by another person or animal like a horse or mouse or by cells in a lab.
A common form of this is when antibodies are pooled from the community and is given intravenously - it’s called intravenous immunoglobulin or IV-Ig.
Passive immunity last for only as long as the antibodies last - usually weeks to months.
The antibodies that an infant receives from their mother in utero or during breastfeeding are examples of passive immunity.
Vaccinations, also known as immunizations, are a way to protect individuals from infectious diseases. Vaccines work by stimulating the immune system to recognize and fight specific pathogens, such as viruses or bacteria. They allow us to develop active immunity where a protective adaptive immune response is made to pathogens without causing disease in the patient.
There are four main types of vaccines: Live attenuated, inactivated, subunit, and toxoid vaccines. Live attenuated and inactivated vaccines are whole-cell vaccines, which means that the whole virus or bacteria is used to create the vaccine. Subunit and toxoid vaccines are considered fractionated vaccines because only one part of the pathogen is used to create the vaccine. Vaccines are typically given through injections, nasal sprays, or oral doses, and are usually recommended for infants and young children, as well as for adults who may be at risk for certain infectious diseases. Some vaccines, such as the flu vaccine, need to be given annually, while others provide lifelong protection after a series of doses.
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