aim: how do vaccinations protect us against disease ? immunity is the ability of an organism to...
TRANSCRIPT
Aim: How do vaccinations protect us against disease ?
Immunity is the ability of an organism to resist disease by identifying and destroying foreign
substances or organisms.
Active immunity
• Naturally acquired active immunity occurs when the person is exposed to a live pathogen, develops the disease, and becomes immune as a result of the primary immune response
• Artificially acquired active immunity can be induced by a vaccine, a substance that contains the antigen.
and cells…
Vaccination
• means of producing immunity against pathogens, such as viruses and bacteria, by the introduction of live, killed, or altered antigens that stimulate the body to produce antibodies against more dangerous forms.
Vaccine is made from
• an antigen isolated or produced from the disease-causing microorganism
• vaccine is injected into the blood stream. The B cells in the blood stream respond to the antigen by producing antibodies
• antibodies bind to the antigen to "neutralize"or inactivate it
• memory cells are produced and remain ready to mount a quick protective immune response against subsequent infection with the same disease causing agent.
Memory Cells and Immunity
Vaccine Mass Production
There is no vaccine for the HIV virus
Electron Micrographs and schematic of HIV
Yellow – lipid bilayer
Red, Black & green – different proteins
HIV attacks the CD4 immune cell
Macrophage
T Cell
Helper T Cell
Killer T Cell
Infected CellAntigens are displayed on surface of macrophage
T cell binds to activated macrophage
T cell, activated by macrophage, becomes a helper T cell
Helper T cell activates killer T cells and B cells
Killer T cells bind to infected cells, disrupting their cell membranes and destroying them
Section 40-2Normal function of a T Cell
Immune cells…
HIV affects T-cells
• A normal T cell count is usually over 1000, although it may dip occasionally to even 400 in response to other infections.
• In HIV we see a decrease in T cells (CD4 cells) over time which does not recover without adequate and long-term control of the HIV virus.
HIV doesn't kill anybody directly…
instead, it weakens the body's ability to fight disease.
Brainstorm
• What vaccinations have you received?
Recommended Vaccinations:
• Hepatitis B • Pneumococcal conjugate vaccine (PCV) • DTaP (diphtheria, tetanus, acellular pertussis) • Hib (meningitis) • IPV (polio) • Influenza WGBH American Experience - The Polio
Crusade• MMR (measles, mumps, rubella) • Varicella (chickenpox) • MCV4 (bacterial meningitis) • Hepatitis A
The Pros and Cons of Vaccinations
The practice of vaccinating ourselves, our children, and our animals to prevent disease is the subject of a great deal of debate. Heated discussions arise over what to vaccinate with, when to vaccinate, who to vaccinate, and even whether to vaccinate at all.