PHSC1312 Microbiology/Immunology Lecture 11 Vaccines

vaccination or immunization

administering a version of a pathogen and stimulating an organism's immune system to produce antibodies against pathogens or toxins

protection without inducing normal disease course

What does vaccination provide a recipient with?

strong B and T cell response resulting in various antibody isotypes and long lasting memory cells

a vaccine ideally stimulates this response

prophylactically

Are most vaccines given prophylactically or therapeutically?

Rabies or HepB

two vaccines that can be given post exposure

rate of replication of pathogen and incubation period

What has to be favorable for post exposure vaccine administration?

allows vaccine to stimulate immune response before the pathogen causes disease

Why is a longer incubation period more favorable for post exposure vaccine administration?

antibodies and vaccine

mixture that induces active immunity

fever, malaise, discomfort at site of injection

common side effects of immunization

joint pain or arthritis, convulsions, neurological disorders

adverse effects of immunization (not as common)

allergies to eggs or other vaccine constituents

may result from viral vaccines produced in eggs

influenza

example of a vaccine sometimes produced in eggs

Live attenuated

vaccines that include live, non pathogenic microbes

treated live, non pathogenic microbes

What do live attenuated vaccines include?

repeated passage in cell culture or intentional mutations

How are microbes treated for live attenuated vaccines to prevent them causing disease?

long lasting, specific

What type of immunity do live attenuated vaccines induce?

live attenuated pediatric immunization

What can be sufficient for lifelong protection?

some attenuated or killed bacterial vaccines induce limited protection, may lead to mild illnesses or cases, not for immunocompromised

disadvantages to live attenuated bacterial and viral vaccines

Sabin polio vaccine, MMR, Varicella zoster, Rotavirus

four examples of live attenuated bacterial and viral vaccines

Inactivated or killed

vaccines composed of intact, inactivated non pathogenic microbes

intact, inactivated non pathogenic microbes

What do inactivated or killed vaccines contain?

immunogenicity, replicating

In inactivated/killed vaccines, microbes retain their _______________ while no longer ______________

boosters

What is often needed for inactivated/killed vaccines to retain a sufficient antibody response?

some do not raise immunity, boosters tend to be needed, little mucosal IgA immunity

What are some disadvantages to inactivated/killed vaccines?

HepA, Salk polio, Rabies post exposure, Typhoid, cholera, plague, Bordetella pertussis, influenza

eight examples of inactivated/killed vaccines

acellular or purified antigen

vaccines composed of antigens purified from microbes or inactivated toxins

antigens purified from microbes or inactivated toxins

What do acellular or purified antigen vaccines contain?

adjuvant

What are acellular or purified antigen vaccines (and other besides live vaccines) administered with?

substance that increases immune response to antigens

What is an adjuvant?

diseases caused by bacterial toxins

What are acellular or purified antigen vaccines important in preventing?

diphtheria, tetanus, pertussis

three toxins that acellular or purified antigen vaccines that prevent against

DTP or DTaP

acellular or purified antigen vaccine for three bacterial toxins

Tdap

booster for an acellular or purified antigen vaccine for three bacterial toxins

polysaccharide antigen

What type of vaccines are pneumococcal and meningococcal?

polysaccharide capsule only

What is in polysaccharide antigen vaccines?

combines polysaccharide from different serotypes of bacteria and attaching them to a protein carrier to form conjugate vaccines

What happens with polysaccharide antigen vaccines?

conjugate vaccines

formed by combining a polysaccharide from a serotype of a bacteria and a protein carrier

serotypes

different strains or variations of the same bacteria that have distinct polysaccharide structures on their surface

diphtheria toxoid

protein carrier for a polysaccharide antigen vaccine example

pneumococcal and meningococcal

polysaccharide antigen vaccine examples

recombinant antigen

vaccines that identify immunodominant microbial antigens/epitopes responsible for producing neutralizing antibodies

immunodominant antigens or epitopes responsible for producing neutralizing antibodies

What is identified to make recombinant antigen vaccines?

clone nucleic acid sequence coding for immunodominant epitopes, transfect into cell expression, purify and use recombinant proteins

three steps to making a recombinant antigen vaccine

nucleic acid and ability to replicate

A recombinant antigen vaccine resembles the virus but lacks what?

Herpes simplex, human papillomavirus, HepB

three recombinant vaccine examples

nucleic acid

vaccines involving inoculation with a plasmid containing complementary DNA (cDNA) or RNA encoding a protein antigen and the host cells make the antigen themselves

plasmid with cDNA or RNA

What does a nucleic acid vaccine contain?

protein antigen

What does the cDNA or RNA in a nucleic acid vaccine encode for?

humoral and cell mediated

What type of immune response do nucleic acids induce?

refrigeration

It is easy to make nucleic acid vaccines store DNA without _____________ for use in the field

covid 19

nucleic acid vaccine example

herd immunity

idea that immunization among the population will limit disease and confer protection to the immunocompromised

adherence of general population to vaccination

What does herd immunity require?