L17-Immunisation and Vaccine Development

These flashcards cover key concepts related to immunisation and vaccine development as outlined in the lecture notes, enhancing the understanding of vaccination principles, types, history, and challenges.

What is immunisation?

The process of stimulating protective immunity against a disease-causing pathogen.

What differentiates natural immunisation from vaccination?

Natural immunisation occurs through exposure to a pathogen and recovery, while vaccination is intentional exposure to a modified form of a pathogen.

What is the main goal of vaccination programs?

To prevent disease, not infection with the pathogen.

What is the historical significance of Thucydides' observations on immunity?

He noted that individuals who recovered from a plague could care for the sick, indicating some level of immunity.

What was Edward Jenner's contribution to immunology?

He began using fluid from cowpox pustules as a vaccine in 1798.

What does passive immunity provide?

Temporary protection relieving symptoms without activating the patient's own B and T cells.

How can passive immunisation occur naturally?

Mother's IgG antibodies pass through the placenta or to the infant via breast milk.

What does active immunization trigger?

It triggers the adaptive immune response to elicit protective immunity.

What is immunological memory?

The hallmark of adaptive immunity, where memory cells respond more vigorously upon re-exposure to the same antigen.

What are the requirements of a good vaccine?

Safe, stable, cost-effective, ease of administration, and long-term protection.

What is herd immunity?

When enough individuals are immune to act as buffers against transmission of a pathogen.

What challenges do global immunization campaigns face?

Distribution to remote areas, lack of effective vaccines, high costs, and public distrust.

What types of vaccines exist?

Whole pathogen vaccines, subunit vaccines, particle-based vaccines, vectored vaccines, and nucleic acid vaccines.

What is the difference between live attenuated and killed vaccines?

Live attenuated vaccines use weakened pathogens; killed vaccines involve inactivating the pathogen.

What are adjuvants?

Substances added to vaccines to enhance or prolong the immune response.

What is the purpose of the clinical trial phases in vaccine development?

To confirm safety and effectiveness before FDA approval.

What are the benefits of live attenuated vaccines?

They promote both humoral and cell-mediated responses and often do not need boosters.

What are some risks associated with live attenuated vaccines?

They may mutate back to a pathogenic form and can have more side effects.

Why do inactivated vaccines often require booster shots?

They do not replicate in the host or induce cell-mediated immunity.

What is a subunit vaccine?

A vaccine using purified macromolecules derived from a pathogen.

What is the role of delivery methods in vaccines?

To ensure effective administration and immune response; options include oral, intramuscular, and novel methods.

What defines a nucleic acid vaccine?

Vaccines that use plasmids or mRNAs carrying pathogen genes injected into muscle tissue.

Why is there a lack of vaccines against certain pathogens?

Due to complex life cycles, antigenic variation, and occupation of privileged sites by pathogens.

What diseases currently have no satisfactory vaccine?

HIV/AIDS, rhinoviruses, gonorrhea, leprosy, syphilis, malaria, and schistosomiasis.

What was the importance of anti-tetanus serum introduced during WWI?

It dramatically reduced the incidence of tetanus among wounded soldiers.

What is the function of memory cells in the immune response?

To respond during secondary exposure to help eliminate the infectious agent.

What factors are considered in designing an immunisation strategy?

Socio-cultural, historical, political, geographic, and religious factors.

What are the advantages of using vectored vaccines?

They combine the benefits of attenuated vaccines while reducing the risk of using actual pathogens.

How do particle or membrane-based vaccines function?

They include an outer envelope that stabilizes and delivers antigens.

What is the significance of antigenic structure in vaccines?

Maintaining antigenic structure is crucial for the effectiveness of the vaccine.

What is a common adjuvant used in vaccines?

Aluminum salts are commonly used to enhance immune responses.

How does the body identify pathogen genes in nucleic acid vaccines?

Through Ag presentation via MHC class I, leading to CTL production.

What is the effect of using combinations of vaccines?

They often increase overall effectiveness and convenience of immunization schedules.

What is the importance of the primary immune response?

It establishes a foundation for long-term immunity and memory cell formation.