Presentation on theme: "Aim: How do vaccinations protect us against disease ? Immunity is the ability of an organism to resist disease by identifying and destroying foreign substances."— Presentation 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.
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.immunity
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 Cell Antigens 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 40-2 Normal function of a T Cell
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 drop 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.
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.
New vaccine to Guard Against HPV PBL HPV and Cervical Cancer Part I “One Less” and “Tell Someone”
Aim: How does the HPV vaccine work to prevent cancer? WILMOT CANCER CENTER University of Rochester We developed a vaccine that could eliminate one cancer from the earth
Understanding Cancer and Related Topics HPV Vaccine To Prevent Cervical Cancer These PowerPoint slides are not locked files. You can mix and match slides from different tutorials as you prepare your own lectures. In the Notes section, you will find explanations of the graphics. The art in this tutorial is copyrighted and may not be reused for commercial gain. Please do not remove the NCI logo or the copyright mark from any slide. These tutorials may be copied only if they are distributed free of charge for educational purposes. The VLP-based vaccine prevents HPV infections from triggering cervical cancer by inducing a strong protective immune response
Common Infection Infected with HPV At least 70 % of sexually active persons will be infected with genital HPV at some time in their lives
Infection Is Sexually Transmitted Anyone who has ever had genital contact with another person infected with HPV can get the infection and pass it to another person
Many Types of HPVs Different HPVs–Different Infections Harmless No warts or cancer Warts-Linked Genital warts Cancer-Linked Most clear up Some persist, but no abnormalities in cervix Some persist, some abnormalities in cervix A few persist and progress to cervical cancer
Virus Penetrates Cervix Uterus HPV infection Vagina Cervix Layers of epithelial cells Papillomavirus Human papillomaviruses pass by skin to skin contact
Virus Uncoats Virus “uncoats” Nucleus Epithelial cell interior mRNAs for viral proteins E6 and E7 Viral DNA enters nucleus
Virus Disables Suppressors Cancerous epithelial cells Suppressor protein 2 E7 viral protein Degraded suppressors Healthy cellsMucus E6 viral protein Suppressor protein 1 Viral proteins disable the normal suppressor genes (“damage surveillance”)
Virus-Like Particles in the HPV vaccine have no genetic material inside but induces the immune response
The Vaccination The vaccination protects a person from future infection by the HPV high-risk types
Antibodies Prevent Infection by coating the antigen of the virus Papillomavirus No DNA strands can escape the capsid = Antibodies
How do we detect abnormal cervical cell growth? Normal Pap smear Abnormal Pap smear