This site is 100% ad supported. Please add an exception to adblock for this site.

Microbiology Unit 5


undefined, object
copy deck
The ability to ward off disease
Nonspecific resistance - 1st line
intact skin, mucous membranes, normal microbiota
Nonspecific resistance - 2nd line
phagocytic white cells, inflammation, fever, antimicrobial substances
Specific resistance - 3rd line
B cells and T cells, antibodies
Ciliary escalator
keeps mucus blanket moving toward the throat
oily substance containing fatty acids, inhibits bacteria
1. Enzyme capable of breaking down cell walls of gram-positive bacteria

2. Found in tears, saliva, nasal secretions, perspiration
ingestion of microorganism by a cell
white blood cells or derivatives of white blood cells
Contains formed elements (cell and cell fragments)
Increase in white blood cells to combat microbes
-Type of leukocyte
Type of granulocyte

Most important phagocyte

Active in initial stage of infection
Role not clear

Release substances such as histamine
Somewhat phagocytic
ability to leave blood

Produce toxic proteins against certain parasites
Enlarged monocyte
Become wandering macrophage and fixed macrophage
predominate as infection subsides
T cells and B cells

Occur in lymphoid tissues of lymphatic system - tonsils, spleen, thymus, red bone marrow, blood
Chemical attraction of phagocytes to microorganisms
coating microbe w/plasma proteins

facilitates adherence to cell
Phagocytosis steps
1. Chemotaxis
2. Ingestion
3. MO surrounded by sac
engulf microorganism

extensions of plasma membrane of phagocyte
Microbial Evasion
Bacteria may inhibit adherence

May be ingested but not killed

Microbes may survive insiode phagocyte
Bodily response to cell damage

Characterized by:
1. Redness
2. Heat
3. Swelling
4. Pain
Dilation of blood vessels

Caused by release of histamine, kinins, and prostaglandins
released in direct respone to the injury of cells that contain it
present in blood plasma

cause vasodilation
intensify effects of histamine and kininds
Blood clots and site
may form to prevent microbe from spreading
Phagocytes begin to stick to the inner surface of the endothelium
Phagocytes begin to squeeze between the endothelial cells of blood vessel
Accumulation of damage tissue and dead microbes, granulocytes, and macrophages
supporting connecting tissue
functioning part of tissue
Stromal repair
Done by fibroblasts

Produces scar tissue
induced by bacterial endotoxins and interleukin-1
Rising body temperature
Crisis (sweating)
Body's temp is falling
Antiviral protein produced in response to viral infection

Host specific but not virus specific

Effective for only short periods
Types of interferon
Alpha, beta, gamma

Also recombant
Defensive system of 30 proteins

In blood serum and tissues
Anti-viral Proteins
Enzymes that disrupt various stages of viral multiplication
Gamma IFN
Produced by lymphocytes

Induces neutrophils and macrophages to kill bacteria by phagocytosis
Proteins, nucleoproteins, lipoproteins
Ability of the body to specifically counteract foreign organisms or antigens
Naturally acquired active immunity
Person is exposed to antigens in course of daily life

measles, chicken pox
Naturally acquired passive immunity
Transfer of antibodies from mother to infant
Artifically acquired active immunity
Artifically acquired passive immunity
Introduction of antibodies (rather than antigens) into the body
Serum containing antibodies
Humoral immunity
Production of antibodies that act against foreign organisms and substances

B Cells responsible for production of antibodies

Defends against bacteria, bacterial toxins
Cell mediated immunity
Depends on T Cells

Does not involve antibody production

Most effective against bacteria and viruses w/in phagocytic cells, fungi, protozoa, helmiths

Primary responder to transplated tissue

Defends against cancer
Antigenic determinant groups
Specific regions on surface of antigen where antibodies are formed
Small compounds that act as carrier molecules for antigens
Antigen binding site
Sites that bind to antigenic determinants

At least two for each antibody
Antibody monomer
Four polypeptide chains - two heavy, two light
B cells
Mature migrate to lymphoid organs

recognizes antigen w/antigen receptors
Activated B cells
Produce clone of plasma cells and memory cells
Plasma cells
Secrete antibody
Memory cells
Recognizes pathogens from previous encounters
IgG antibodies
Inactivate viruses and neutralize bacterial toxins
Antigen-antibody complexes
involves IgG and IgM antibodies to fix complement

Results in lysis of bacterial cell
Antibody titer
Amount of antibody in serum
Primary response
Appearance of IgM then IgG
Secondary response
high antibody titer, primarily IgG
Edward Jenner
Developed modern practice of vaccination

Innoculation w/cowpox virus
Attenuated whole-agent vaccine
Living, weakened microbes

More closely mimic actual infection

Polio vaccine, MMR, TB, Rickettsia

Not recommended to people w/compromised immune systems
Inactivated whole-agent vaccine
Use killed microbes

Influenza, polio, pneumonia, cholera, pertussis, typhoid
Inactivated toxins

Directed at toxins produced by pathogen

Tetanus and diptheria
Subunit vaccines
Use antigenic fragments of microorganism to best stimulate immune response

Hepatitis B, Cholera, Streptococcus
Conjugated vaccine
Combine desired antigen w/protein to boost immune system

Hib vaccine
Nucleic Acid vaccine (DNA vaccine)
Recipient makes antigenic proteins

Do not need to be grown in cells or animals

Influenza A
Where to grown viruses for vaccines
Animals, cell cultures, chick embryos
nonspecific antigens and indiscrimantely acitive T cell receptors at once
Antigenic response beyond that which is considered normal
Type I (Anaphylactic) reaction
Occur wi/in 2 to 30 minutes of exposure

Production of IgE antibodies that bind to mast cells and basophils

Target cell release chimical mediators (kinin, histamine, leukotrienes)
Reactions caused when certain antigens combine w/IgE antibodies

Systemic-shock, breathing difficulties

Localized-hay fever, asthma, hives
Repeated injections of antigen, leads to formation of IgG antibodies
Blood type
Determined by presence or absence of two carbohydrates
No anti-A or anti-B antibodies

Universal recipient - can get A, B, AB, O types
Anti-A antibodies

Can have B, O blood
Anti-B antibodies

Can have A, O blood
Anti A and Anti-B Antibodies

Can have O blood, universal donor
Rh factor
Surface antigen

85% population are Rh+
Rh+ blood type
Can receive Rh+ or Rh-
Rh- blood type
If receives Rh+, donor's RBC stimulate anti-Rh antibodies

If receives subsequent Rh+, hemolytic reaction
Hemolytic disease of newborn
Rh- carries Rh+ fetus, anti-Rh antibodies

Can be prevented by mother receiving anti-Rh antibodies (Rhogam)
Loss of self-tolerance
Type I Autoimmunity
Antibodies that attack self

Hepatitis C - autoimmune hepatitis
Type II (Cytotoxic) Autoimmunity
Antibody reactions to cell-surface antigens

Graves' disease, myasthenia gravis
Type III (Immune complex) autoimmunity
Antibodies directed at components of own cells

Lupus, Rheumatoid arthritis
Type IV (Cell-Mediated) Autoimmunity
T cells

MS, Hashimoto's Thyroiditis
Histocompatability antigens
located on cell surfaces

Express genetic differences among individuals
Transplant compatability
Match HLA and ABO antigens

If recognized as foreign, may be lysed by T cells and attacked by macrophages
Privileged transplation site
Antibodies do not circulate

Privileged transplantation tissue
Does not stimulate immune rejection

Pig heart
One's own tissue grafted to another part of body
Identical twin grafting
Grafts between people who are not identical twins
Xenotransplatation products
Tissues or organs from animals
Immunosuppressant drug

Inhibits secretion of IL-2

Deck Info