CIE 11.1 Types of Immunity and Vaccination (A-level biology & Osmosis)

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is primarily responsible for the development of immunological memory during a primary infection?

Activation of memory cells (correct)

Absence of viral exposure

Interference from other immune responses

Antigens from pathogens deteriorating

How does natural immunity differ from artificial immunity?

Natural immunity requires vaccines to develop

Natural immunity provides immediate protection

Natural immunity results from direct pathogen exposure (correct)

Natural immunity is only short-term

Which of the following statements about vaccines is correct?

Vaccines are not effective in generating memory cells

Vaccines stimulate the immune system using live viruses

Vaccines can be made from dead or weakened viruses (correct)

Vaccines are designed to combat bacteria primarily

Which type of immunity is characterized by the body producing its own antibodies?

Active immunity Signup and view all the answers

What is the primary benefit of booster vaccinations?

They enhance the immune response and combat fading immunity Signup and view all the answers

Which statement is true about passive immunity?

It relies on the direct injection of antibodies from another animal Signup and view all the answers

What role do antibodies play in natural immunity obtained from breastfeeding?

They pass from mother to infant providing temporary immunity Signup and view all the answers

Which of the following is a characteristic of artificial immunity?

It is established through the administration of vaccines Signup and view all the answers

What is the primary benefit of vaccination in relation to pathogen recognition?

It enables the immune response to occur quickly. Signup and view all the answers

Herd immunity is crucial primarily for which group?

Infants who cannot yet be vaccinated. Signup and view all the answers

What can lead to the loss of herd immunity in a population?

Decreased vaccination rates. Signup and view all the answers

Antigenic drift differs from antigenic shift in what significant way?

Drift is a gradual change, while shift is sudden and significant. Signup and view all the answers

Why is antigenic variation a challenge for developing vaccines for the influenza virus?

New strains arise and change antigens frequently. Signup and view all the answers

In the context of tuberculosis, what is the primary survival advantage of the TB bacteria?

Thick waxy cell wall that resists destruction. Signup and view all the answers

How does HIV primarily evade the immune system?

By altering its antigens rapidly. Signup and view all the answers

What is the typical time frame for the primary immune response following infection?

Around two weeks. Signup and view all the answers

Vaccines primarily stimulate which part of the immune system?

Humoral immunity. Signup and view all the answers

Which characteristic of HIV makes it particularly difficult to treat?

It has a high mutation rate. Signup and view all the answers

Why does mass vaccination contribute to herd immunity?

It reduces the overall number of susceptible individuals. Signup and view all the answers

What is the risk associated with not renewing vaccinations over time?

Loss of herd immunity and possible disease resurgence. Signup and view all the answers

Antigenic variability primarily affects which vaccine preparation strategy?

Annual updates to flu vaccines. Signup and view all the answers

The waxy cell wall of tuberculosis bacteria contributes to its ability to:

Survive inside macrophages. Signup and view all the answers

What is the primary function of antibodies produced by plasma cells?

To neutralize pathogens and mark them for destruction. Signup and view all the answers

During the activation of B cells, which of the following cells provides necessary assistance?

T helper cells Signup and view all the answers

What happens after B cells recognize and bind to specific antigens?

They become activated and multiply into plasma cells. Signup and view all the answers

Which of the following accurately describes an action taken by antibodies?

They block the pathogens' ability to infect cells. Signup and view all the answers

How do plasma cells contribute to humoral immunity?

By producing and releasing large amounts of antibodies. Signup and view all the answers

Which vaccination route is primarily responsible for eliciting an IgG immunoglobulin response?

Orally Signup and view all the answers

What is a characteristic of inactivated vaccines?

They use pathogens killed by formalin or heat. Signup and view all the answers

Which vaccine type is ineffective in producing a response in children and pregnant women?

Polysaccharide vaccines Signup and view all the answers

What distinguishes a subunit vaccine from a whole-cell vaccine?

Subunit vaccines consist of immunogenic portions of the pathogen. Signup and view all the answers

What is the potential side effect associated with polysaccharide vaccines?

Guillain-Barré syndrome Signup and view all the answers

Study Notes

Types of Immunity

Natural Immunity: Develops after infection, resulting from the body’s immune response to antigens.
Primary Immune Response: When encountering a pathogen for the first time, the body generates memory cells, leading to immunological memory.
Secondary Immune Response: In a subsequent infection, memory B cells and antibodies quickly eliminate the pathogen.
Maternal Antibodies: Infants can acquire natural immunity through breastfeeding, where antibodies pass from mother to child.

Artificial Immunity

Vaccines: Artificial immunity is primarily obtained through vaccinations, which contain dead or weakened viruses.
Function of Vaccines: Vaccines induce the immune system to create immunological memory against infections, preparing it to respond quickly to live pathogens.
Virus-Specific: Current vaccines are only designed to combat viruses, not bacterial infections.

Active and Passive Immunity

Active Immunity: Develops when the body produces its own antibodies in response to exposure to pathogens.
Vaccination and Active Immunity: Vaccines stimulate active immunity, requiring memory B cells and antibodies for long-lasting protection.
Booster Shots: Some vaccines may require booster doses over time to maintain immunity due to fading immunological memory.
Passive Immunity: Comes from antibodies transferred from another animal or a human, providing immediate protection.
Emergency Treatment: In cases of infection, patients can be treated with injected antibodies for quick immune response support.

Importance of Vaccination

Development of Immunity: While the immune system can develop natural immunity post-infection, this process typically takes two weeks.
Rapid Response: Vaccination can prime the immune system for faster responses, often within seven days of exposure.

Herd Immunity

Concept of Herd Immunity: Achieved when a significant portion of the population is vaccinated, disrupting the chain of pathogen transmission.
Protection for Vulnerable Populations: Infants and individuals unable to get vaccinated benefit from herd immunity, which protects against outbreaks.
Risks of Low Vaccination Rates: Decreased vaccination can cause the resurgence of diseases that were nearly eradicated, putting vulnerable populations at risk.

Ethics of Vaccination

Vaccine Hesitancy Impact: A drop in vaccination rates can jeopardize herd immunity, leading to disease outbreaks.
Historical Resurgence: Diseases like whooping cough and MMR saw a comeback partly due to vaccination fears, endangering infants.

Antigenic Variability

Importance of Antigens: Vaccines rely on stable antigens for effective immunity. Changes in antigens can diminish vaccine effectiveness.
Antigenic Drift vs. Shift: Drift involves minor changes to antigens creating new strains, while shift consists of major changes leading to entirely new viruses.

Influenza Virus Case Study

Rapid Evolution: Influenza viruses mutate quickly, necessitating new vaccines annually based on prevalent strains.
Vaccination Participation: Low vaccination rates contribute to the emergence of new strains, complicating control efforts.

Evolutionary Race between Pathogens and Host

TB Pathogen Characteristics: TB bacteria have a thick cell wall, enabling them to survive inside macrophages, leading to dormant infections.
HIV Pathogen Characteristics: HIV mutates rapidly, impeding memory cell recognition, and initially targets helper T cells, compromising the immune response.
Dormancy of HIV: The virus can remain dormant for up to ten years, later reactivating without external reinfection.

Humoral Immunity Overview

Humoral immunity is a crucial part of the immune system responsible for defending against infections through antibody production.
Antibodies are specialized proteins produced by B cells, a type of white blood cell, found in blood and body fluids.

Mechanism of Action

Recognition: B cells identify harmful invaders, such as bacteria or viruses, by detecting specific molecules known as antigens on their surface.
Activation: Upon recognizing an antigen, B cells become activated, often with assistance from T helper cells. This leads to B cell proliferation and differentiation into plasma cells.

Antibody Production and Function

Plasma Cells: Once activated, B cells transform into plasma cells, which are responsible for producing and releasing large quantities of antibodies into the bloodstream.
Neutralization of Pathogens:
- Antibodies bind to antigens on pathogens, preventing them from infecting host cells.
- They label pathogens for destruction by other immune cells, such as macrophages.
- Antibodies can also activate complement proteins, which aid in the destruction of the pathogen.

Administration Routes

Intramuscularly: Injection deep into muscle tissue.
Intradermally: Injection into the dermis, the layer beneath the outer skin.
Intranasally: Delivery through the nasal passages for quicker absorption.
Subcutaneously: Injection into the layer of fat beneath the skin.
Orally: Administration via the mouth, allowing gastrointestinal absorption.

Immunoglobulin Response

Routes of vaccination influence the immunoglobulin produced.
Intramuscular vaccinations primarily generate IgG antibodies.
Oral vaccines, such as the rotavirus vaccine, also elicit IgG responses.

Types of Vaccines

Whole Cell Vaccines: Consist of either live attenuated (weakened) or inactivated (killed) pathogens.
Fractionated Vaccines: Comprised of subunits or toxoids derived from pathogens.

Inactivated Vaccines

Pathogens are killed using formalin or heat, preventing disease.
Induce a humoral (antibody-mediated) immune response but do not foster cellular immunity, resulting in a reduced response.
Examples include polio, hepatitis A, rabies, and influenza vaccines.

Subunit Vaccines

Contain immunogenic components from pathogens, such as polysaccharides or proteins.
Conjugate subunit vaccines combine proteins from different pathogens to enhance immune response.

Polysaccharide Vaccines

A specific type of subunit vaccine that triggers a T-cell independent response, mainly against protein antigens.
Less effective in children and pregnant women.
Associated with the risk of rare complications, such as Guillain-Barré syndrome.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

This quiz explores the different types of immunity including natural and artificial immunity. It covers how natural immunity develops after infection and the role of immunological memory. Participants will learn about the primary immune response and its significance in fighting secondary infections.