Unit 1 Cram sheet - PLTW, MedInt

Making Vaccines

Effective Vaccines

  • Have low levels of side effects or toxicity

  • Protect against exposure to natural, or wild forms of the pathogen

  • Should stimulate both and antibody (B-cell) response & a cell mediated (T-cell) response

  • Have long term, lasting effects that produce immunological memory

  • Should NOT require numerous doses or boosters

  • Are inexpensive, have a long shelf life, & are easy to administer.

Routes of administration

  • The majority of vaccines are administer by injection (Subcutaneous, Intramuscular, Intradermal)

  • Oral vaccines are available for only a few diseases

Types of vaccines

  • Killed whole cells or inactivated viruses. Even though they are harmless, they still contain recognizable antigens on their surface. Because the microbe does not multiply, lager doses & more boosters are required.

  • Live, attenuated (weakened) cells or viruses. Vaccines are longer-lasting and require fewer boosters, however, the disease agent could mutate back to the pathogenic strain.

  • Toxoid vaccines. A purified toxin produced by the antigen is used to elicit immune response

  • Genetically engineered microbes or microbial antigens. Genes for microbial antigens are inserted into a plasmid vector & are cloned in appropriate hosts. The resultant protein product is used to provoke the immune system.

  • DNA vaccines. These vaccines contain all or part of the pathogen DNA, which is used to “infect” a recipient’s cells

Herd Immunity

  • The more individuals that are immune decreases the incidence of the disease and the occurrence of the pathogen.

  • With greater numbers immunized, it is less likely that an unimmunized person will encounter the pathogen.

  • Mass baccination confers indirect protection for those who do not receive the vaccine, resulting in “herd immunity”.

Medical Interventions

    A medical intervention is anything that is used to treat, prevent, cure, or relieve the symptoms of human suffering, whether is is caused by a disease, accident, or something as simple as hygiene. Officially, a medical intervention is a measure used to improve health of alter the course of an illness & can be used to prevent. diagnose. & treat disease. Medical interventions can be broken down into categories & grouped together. Some of these categories are: Genetics, pharmacology, diagnostics, surgery, immunology, medical devices, & rehabilitation.

    Client issues that can be measured & recorded are typically referred to as signs - temperature, heart rate, blood pressure, rash, swollen glands, etc. - While problems the patient reports are considered symptoms (tiredness, sore throat, nausea, etc.).

Procedures & tests

BLAST

A form of DNA sequencing run through a database containing millions of organisms’ DNA samples

  1. isolate the disease-causing agent via “plating”

  2. lyse pathogen

  3. amplify

  4. run through BLAST

ELISA

Enzyme-linked Immunosorbent Assay

  • Takes advantage of the body’s natural immune responses to identify the presence of illness

  • Color change means a positive result

  • The stronger the color, the more present whatever you’re testing is.

  • A qualitative result, but when compared to a serial dilution, it is a quantitive result.

  • Whoever had the most antigen was most likely the first person infected

Steps:

  1. Primary antibody (latches onto antigen)

  2. Secondary antigen & enzyme (attaches onto primary antibody)

  3. substrate (acts on enzyme & causes color change)

Serial Dilution

Something that is created & used to compare the results of an ELISA to. It involves beginning with a known concentration of an antigen & diluting it.

Serial Dilutions

Terms

Qualitative vs. Quantitative Result

Something that is simply observed, such as “hot/cold”, “soft/hard”, “clear/blue”. is a Qualitative result. Qualitative results are NOT measurable.

Qualitative results ARE measurable

Antigen

A type of protein found on the outside of every living cell (and virus). Antigens are surface markers that your cells use to identify each other. Antigens on the outside of a bacteria are very different from that of your cells, Because of this, your body’s immune system cells (WBC) are able to identify them & mount a defense against them, hopfully killing those pathogens before they can make you sick or kill you.

Antibodies

If a pathogen is able to get through your body’s non-specific defenses (skin, mucous, urine, etc.), which are designed to keep things out of your body, then more specific defenses are activated. One of these defenses are antibodies. Antibodies are produces by a type of leukocyte called a B lymphocyte. The job of an antibody is to attach to foreign antigens. By attaching, those foreign antigens are neutralized. This attachment also signals to other types of leukocytes (T lymphocytes) to come in & destroy whatever the antibody is attached to.

Nucleoid

Gel-like region within the cytoplasm containing the single, circular, double-stranded DNA molecule. This chromosomal DNA is supercoiled, meaning tightly packed into a twisted form. The DNA contains all of the genetic information necessary for normal functioning of the cell.

Plasmids

Circular, double-stranded DNA molecules. They are typically 0.1% to 10% of the size of the chromosomal DNA, and only carry a few to several hundred genes. A single bacteria cell can carry multiple plasmids. Normal functioning of a bacterial cell is not dependent on the genetic information contained in the plasmid, but the DNA in the plasmid often codes for proteins that are advantageous to the cell. For instance, plasmids might contain the information coding for the proteins that enable the cell to destroy or be immune to certain antibodies. Plasmids can be transferred from one bacterial cell to another bacterial cell.

Ribosomes

Structures that involve protein synthesis. They facilitate the joining of amino acids.

Cell wall

Rigid barrier that surrounds the cell, keeping the contents from bursting out. Peptidoglycan provides the rigidity for the cell wall.

Plasma membrane

(also called the cytoplasmic membrane). Semipermeable membrane the surrounds the cytoplasm of the cell. This phospholipid bilayer is embedded with proteins that act as a barrier between the cytoplasm & the outside environment.

Capsule

A distinct and gelatinous layer, called glycocalyx, enveloping the cell. This layer enables bacterial cells to adhere to specific surfaces and sometimes protects bacterial cells from the immune system.

Flagella

Protein appendages that are anchored in the membrane and protrude out from the surface. The flagella spin like propellers, moving the bacterial cell forward.

Pili

Filamentous appendages which are similar in structure to flagella, but function in a different manner. Some pili enable the bacterial cell to attach to a specific surface (these pili are called fimbriae). Other pili are involved in conjugation. These pili are called sex pilus.

Bacteria & Antibiotic Treatment

Gram Negative Bacteria

  • Cell wall contains multiple layers, including a thin layer of peptidoglycan.

  • The outside layer is called th outer membrane, which is made of a lipid bilayer whose outside is composed of lipopolysaccharides called endotoxins.

  • The outer membrane serves as a barrier to the passage of most molecules & contains specialized proteins called porins, which allow certain molecules to pass through the membrane.

  • The region between the plasma membrane & the outer membrane is called the periplasm, and is filled with a gel-like fluid and proteins involved in a variety of cellular activities.

  • The Gram-stained cell is reddish-pink.

Gram Positive Bacteria

  • The cell wall contains a thick layer of peptidoglycan and teichoic acids. There is approximately twenty times more peptidoglycan than the gram negative bacteria.

  • There is no outer membrane present

  • There are no porins present

  • The Gram-stained cell is purple.