Immunology and Immunological Preparations One Shot Notes and MCQs
Immunology and Immunological Preparations
1. Principles of Immunology
Immunology is the branch of biology that studies the immune system and how the body defends itself from foreign invaders such as bacteria, viruses, and other pathogens. The immune response involves various cells, molecules, and reactions designed to recognize and neutralize harmful agents.
2. Antigens and Haptens
- Antigen: A substance that stimulates an immune response by the production of antibodies. They are typically proteins or polysaccharides found on the surface of pathogens.
- Hapten: A small molecule that, by itself, is not immunogenic but becomes immunogenic when attached to a larger carrier molecule. Haptens can cause allergic reactions (e.g., penicillin allergy).
3. The Immune System
The immune system is divided into:
- Innate Immunity: The non-specific first line of defense (e.g., skin, mucous membranes, phagocytes).
- Adaptive Immunity: Specific immunity involving recognition of specific antigens and memory formation. It includes:
- Cellular Immunity: T-cells destroy infected or cancerous cells.
- Humoral Immunity: B-cells produce antibodies against pathogens in body fluids.
4. Immunological Tolerance
- Immunological tolerance: The immune system’s ability to distinguish between self and non-self and to avoid attacking its own cells.
- Central tolerance occurs during immune cell development (in the thymus and bone marrow), while peripheral tolerance prevents autoimmune responses in mature immune cells.
5. Antigen-Antibody Reactions and Applications
Antibodies bind specifically to antigens to neutralize pathogens. The major reactions include:
- Precipitation: Soluble antigen-antibody complexes form a precipitate.
- Agglutination: Antibodies clump particulate antigens (e.g., blood cells in blood grouping).
- Neutralization: Antibodies block the harmful effects of toxins or viruses.
- Complement fixation: Antibody binding activates the complement system, leading to cell lysis.
Applications:
- Diagnosis of infectious diseases (e.g., ELISA, Western Blot).
- Blood grouping and transfusion testing.
- Immunotherapy (e.g., monoclonal antibodies in cancer treatment).
6. Hypersensitivity Reactions
Hypersensitivity refers to exaggerated immune responses that can cause tissue damage. It is classified into four types:
- Type I (Immediate): IgE-mediated reactions (e.g., allergies, anaphylaxis).
- Type II (Cytotoxic): Antibody-mediated cell destruction (e.g., hemolytic anemia).
- Type III (Immune Complex): Immune complexes cause inflammation (e.g., serum sickness).
- Type IV (Delayed-type): T-cell-mediated (e.g., contact dermatitis).
7. Active and Passive Immunization
- Active Immunization: Stimulating the body’s immune response by administering a vaccine containing antigens. It provides long-term immunity.
- Example: MMR vaccine, polio vaccine.
- Passive Immunization: Providing pre-formed antibodies (in the form of sera) to offer immediate protection, but the immunity is short-lived.
- Example: Anti-venom for snake bites, immunoglobulin injections.
8. Vaccines and Sera: Preparation, Standardization, and Storage
Vaccines
Vaccines are biological preparations that provide immunity against specific diseases. Types of vaccines include:
- Live-attenuated vaccines: Contain weakened forms of the pathogen (e.g., measles, mumps).
- Inactivated vaccines: Contain killed pathogens (e.g., inactivated polio vaccine).
- Subunit/conjugate vaccines: Contain only parts of the pathogen (e.g., hepatitis B vaccine).
- Toxoid vaccines: Contain inactivated toxins (e.g., diphtheria and tetanus toxoids).
- mRNA vaccines: Use synthetic mRNA to instruct cells to produce viral proteins (e.g., COVID-19 vaccines).
Standardization and Storage:
- Vaccines are standardized to ensure safety, efficacy, and consistency.
- They are stored under cold conditions (2-8°C) to maintain potency. Some vaccines (like mRNA vaccines) require ultra-low temperatures.
Sera (Antisera)
- Sera contain antibodies extracted from animals or humans exposed to a specific antigen.
- Used for passive immunization, such as anti-rabies serum or tetanus antitoxin.
Standardization and Storage:
- Antisera are standardized based on potency and dose.
- Stored at low temperatures to prevent degradation.
MCQs on Immunology and Immunological Preparations
- Which type of immunity involves T-cells directly attacking infected cells?
a) Humoral immunity
b) Cellular immunity
c) Passive immunity
d) Innate immunity
Answer: b) Cellular immunity - What type of molecule is a hapten?
a) Large protein
b) Small molecule requiring a carrier to become immunogenic
c) Lipopolysaccharide
d) Antibody fragment
Answer: b) Small molecule requiring a carrier to become immunogenic - Which antibody is responsible for allergic reactions?
a) IgG
b) IgM
c) IgE
d) IgA
Answer: c) IgE - Which of the following is an example of Type IV hypersensitivity?
a) Anaphylaxis
b) Hemolytic anemia
c) Serum sickness
d) Contact dermatitis
Answer: d) Contact dermatitis - What is the purpose of adjuvants in vaccines?
a) To inactivate the virus
b) To increase immune response
c) To stabilize vaccine proteins
d) To suppress the immune response
Answer: b) To increase immune response - Which type of vaccine uses weakened pathogens?
a) Subunit vaccine
b) Inactivated vaccine
c) Toxoid vaccine
d) Live-attenuated vaccine
Answer: d) Live-attenuated vaccine - What is the primary antibody found in the blood?
a) IgA
b) IgM
c) IgG
d) IgD
Answer: c) IgG - Which of the following is an example of active immunity?
a) Receiving antitoxin for tetanus
b) Immunity acquired after a measles infection
c) Receiving immunoglobulin for hepatitis
d) Injection of monoclonal antibodies
Answer: b) Immunity acquired after a measles infection - What is the term for the immune system’s ability to avoid attacking the body’s own cells?
a) Immunological tolerance
b) Humoral immunity
c) Innate immunity
d) Hypersensitivity
Answer: a) Immunological tolerance - Which immune cells produce antibodies?
a) T-cells
b) B-cells
c) Macrophages
d) Natural killer cells
Answer: b) B-cells - Which immunoglobulin is involved in mucosal immunity?
a) IgE
b) IgG
c) IgA
d) IgM
Answer: c) IgA - What type of hypersensitivity involves immune complexes?
a) Type I
b) Type II
c) Type III
d) Type IV
Answer: c) Type III - Which reaction is used to determine blood groups?
a) Precipitation reaction
b) Agglutination reaction
c) Neutralization reaction
d) Complement fixation
Answer: b) Agglutination reaction - What is the primary function of T-helper cells?
a) Produce antibodies
b) Activate other immune cells
c) Kill infected cells
d) Suppress immune response
Answer: b) Activate other immune cells - What is passive immunity?
a) Immunity achieved by vaccination
b) Transfer of antibodies from an external source
c) Immunity provided by memory cells
d) Immunity from live-attenuated vaccines
Answer: b) Transfer of antibodies from an external source - Which test uses an antigen-antibody reaction to detect HIV?
a) ELISA
b) PCR
c) Western blot
d) Hemagglutination test
Answer: a) ELISA - Which immunoglobulin is the largest in size?
a) IgA
b) IgG
c) IgM
d) IgE
Answer: c) IgM - Which of the following is a toxoid vaccine?
a) Polio vaccine
b) Diphtheria vaccine
c) Hepatitis B vaccine
d) Measles vaccine
Answer: b) Diphtheria vaccine - What is the purpose of sterility testing in vaccines?
a) To confirm antigen stability
b) To ensure the absence of microbial contamination
c) To verify antibody production
d) To standardize the vaccine dose
Answer: b) To ensure the absence of microbial contamination - Which cells are involved in humoral immunity?
a) Macrophages
b) B-cells
c) T-cells
d) Dendritic cells
Answer: b) B-cells - What is the term for antibodies binding to soluble antigens to form a visible precipitate?
a) Agglutination
b) Precipitation
c) Neutralization
d) Complement fixation
Answer: b) Precipitation - Which hypersensitivity reaction occurs immediately after exposure to the allergen?
a) Type II
b) Type IV
c) Type I
d) Type III
Answer: c) Type I - What is the role of natural killer (NK) cells?
a) Produce antibodies
b) Phagocytose pathogens
c) Destroy virus-infected cells
d) Present antigens to T-cells
Answer: c) Destroy virus-infected cells - Which immunoglobulin is transferred from mother to baby through the placenta?
a) IgG
b) IgA
c) IgE
d) IgM
Answer: a) IgG - Which method is used to determine the potency of vaccines?
a) ELISA
b) Sterility testing
c) Animal models
d) Agglutination test
Answer: c) Animal models - Which immune response is faster on subsequent exposure to the same antigen?
a) Primary immune response
b) Secondary immune response
c) Innate immune response
d) Passive immune response
Answer: b) Secondary immune response - Which vaccine type does not contain live organisms?
a) Inactivated vaccine
b) Live-attenuated vaccine
c) Conjugate vaccine
d) Recombinant vaccine
Answer: a) Inactivated vaccine - What is used to assess the sterility of pharmaceutical products?
a) Blood test
b) Culture media
c) ELISA test
d) PCR
Answer: b) Culture media - Which term describes an exaggerated immune response to a harmless antigen?
a) Autoimmunity
b) Hypersensitivity
c) Immunodeficiency
d) Tolerance
Answer: b) Hypersensitivity - Which component is essential in passive immunity?
a) Memory cells
b) Live virus
c) Antibodies
d) Antigens
Answer: c) Antibodies
Also, Visit:
B. Pharma Previous Year Question Paper