Tag: zoology

• Passive immunity is the protection against disease through antibodies produced by another human being or animal.
• Passive immunity doesn't last as long as active immunity.
• Emil von Behring was awarded the first Nobel Prize in Physiology or Medicine in 1901 for his discovery of serum therapy for diphtheria. He showed that serum from rabbits immunized with tetanus toxin could prevent tetanus in rabbits because it contains antibodies against tetanus.
• Hence the method of passive immunity was discovered by Von Behring.
•  So, the correct answer is 'Von Behring'.

Passive immunity is the transfer of active humoral immunity of ready-made antibodies (exogenous). Passive immunity can occur naturally, when maternal antibodies are transferred to the fetus through the placenta, and it can also be induced artificially when high levels of antibodies specific to a pathogen or toxin are transferred to non-immune persons through blood products that contain antibodies. Passive immunization can be provided when people cannot synthesize antibodies, and when they have been exposed to a disease against which a person is not immunized.

Vaccination is the administration of antigenic material (a vaccine) to stimulate an individual's immune system to develop acquired immunity to a pathogen. Upon administration of attenuated or inactivated antigen (vaccine), the antibodies are produced by plasma cells and memory cells are activated. When the same antigen attacks the person in future, the memory cells recognize the antigen and promotes phagocytosis.

A lymphocyte is one of the subtypes of white blood cell in a vertebrate's immune system. Lymphocytes include natural killer cells (which function in cell-mediated, cytotoxic innate immunity), T cells (for cell-mediated, cytotoxic acquired immunity), and B cells (for humoral, antibody-driven adaptive immunity). The total number of lymphocytes present in healthy humans is approximately 1 trillion.

Active immunity is the induction of immunity after exposure to an antigen. Antibodies are created by the recipient and may be stored permanently due to the activation of memory cells which recognizes the same antigen in future and destroy them. Active immunity can occur naturally when a microbe or other antigen is received by a person who has not yet come into contact with the microbe and has no pre-made antibodies for defence.

The adaptive immune system, also known as the acquired immune system is composed of highly specialized, systemic cells and processes that eliminate pathogens or prevent their growth. The acquired immune system is one of the two main immunity strategies found in vertebrates. Acquired immunity creates immunological memory after an initial response to a specific pathogen, and leads to an enhanced response to subsequent encounters with that pathogen.

The inflammatory response (inflammation) occurs when tissues are injured by bacteria, trauma, toxins, heat, or allergy. The damaged cells release chemicals including histamine, bradykinin, and prostaglandins. Histamine is released from mast cells. These chemicals cause blood vessels to leak fluid into the tissues, causing swelling. 

• In our body, neutrophils, macrophages and lymphocytes are involved in the second line of defence. They produce non-specific immune responses such as fever and inflammatory response.
•  Neutrophils are a type of WBC and they form an essential part of the innate immune system. Neutrophils are one of the first-responders of inflammatory cells to migrate towards the site of inflammation.
• Macrophages are the type of WBC which engulfs and digests cellular debris, foreign substances, microbes etc..
• Lymphocytes are a type of WBC. It includes natural killer cells (which function in cell-mediated, cytotoxic innate immunity), T cells (for cell-mediated, cytotoxic adaptive immunity), and B cells (for humoral, antibody-driven adaptive immunity). 

• Acquired immunity is the immunity obtained either from the development of antibodies in response to exposure to an antigen, as from vaccination or an attack of an infectious disease or from the transmission of antibodies, as from mother to fetus through the placenta or the injection of antiserum.
  
• Active acquired immunity results from the development of antibodies in response to an antigenic stimulus, as from exposure to an infectious disease or through vaccination.
• Hence, resistance developed in an individual as a result of antigenic stimulus is due to Active acquired immunity.