Immunology

Immunology is the branch of biology which study about immune system.

It deals with how body protect itself from pathogens, like bacteria, virus, fungi, parasites and other foreign particles.

In immunology we study about-

  • Immune system– body defense system
  • Immune cells– like T cells, B cells, macrophages, neutrophils
  • Antibodies– proteins which help to fight antigen
  • Antigens– foreign substances which trigger immune response
  • Immunity– protection power of body
  • Vaccines– artificial way to develop protection
  • Immune disorders– like allergy, autoimmune disease, immunodeficiency

So, simple meaning-

Immunology is the study of body defense mechanism against harmful foreign agents.

Type III Hypersensitivity – Definition, Types, Mechanism, Examples

• • 17 min readby
Type III Hypersensitivity - Definition, Types, Mechanism, Examples

What is Type III Hypersensitivity? Definition of Type III Hypersensitivity Type III hypersensitivity is an allergic reaction characterized by the accumulation of immune complexes (antigen-antibody complexes) in tissues, leading to inflammation and tissue damage. Types of Type III hypersensitivity reaction Type III hypersensitivity reactions can be categorized into localized and generalized reactions. The manifestation of … Read more

Major Histocompatibility Complex I – Definition, Structure, Mechanism, Functions

• • 16 min readby
Major Histocompatibility Complex I - Definition, Structure, Mechanism, Functions

What is Class I MHC (Major Histocompatibility Complex) molecules? Cellular Distribution of Major Histocompatibility Complex I (MHC I) Major Histocompatibility Complex I (MHC I) Structure The majority of nucleated cells have an assortment of MHC class I proteins. The peptides bound by these MHC class I molecules are typically endogenous, or derived from the breakdown … Read more

Type IV or Delayed-Type Hypersensitivity (DTH)

• • 22 min readby
Type IV or Delayed-Type Hypersensitivity (DTH)

What is Type IV or Delayed-Type Hypersensitivity (DTH)? Definition of Type IV or Delayed-Type Hypersensitivity (DTH) Type IV or Delayed-Type Hypersensitivity (DTH) is an immune response mediated by T cells rather than antibodies, characterized by a delayed onset (usually 24-72 hours) after exposure to an antigen. It involves the interaction of CD4+ T cells, monocytes, … Read more

Major Histocompatibility Complex II (MHC II molecules) – Structure, Mechanism and Functions

• • 17 min readby
Major Histocompatibility Complex II (MHC II molecules) - Structure, Mechanism and Functions

What is Major Histocompatibility Complex II (MHC II molecules)? Cellular Distribution of Major Histocompatibility Complex II (MHC II molecules) Structure of Major Histocompatibility Complex II (MHC II molecules) As stated previously, MHC class II molecules are nearly exclusively located on APCs. The peptides bound by MHC class II are produced from the breakdown of proteins … Read more

Lymph Nodes – Definition, Location, Structure and Functions

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Lymph Nodes - Definition, Location, Structure and Functions

What is Lymph Nodes? Definition of Lymph Nodes Lymph nodes are small organs in the lymphatic system that filter lymph and play a critical role in the body’s immune response. Location of Lymph Nodes Size of Lymph Nodes The size of lymph nodes can vary depending on their location within the body. Here are some general guidelines … Read more

Passive Immunization – Definition, Advantages, Disadvantages, Examples

• • 12 min readby
Passive Immunization - Definition, Advantages, Disadvantages, Examples

What is Passive Immunization? Definition of Passive Immunization Passive immunization refers to the direct administration of pre-formed antibodies or immune cells from another individual to provide immediate protection against infectious agents or toxins. Process of Passive Immunization Passive immunization involves the direct transfer of pre-formed antibodies or immune cells from a donor to an individual … Read more

Inflammation – Definition, Types, Causes, Mechanism

• • 1 revisions • 25 min readby
Inflammation - Definition, Causes, Symptoms

Inflammation is a protective reaction of body against injury, infection and harmful substances. It is a part of innate immune system. It helps to remove the harmful agent and starts tissue repair.Inflammation is a protective defence reaction of the body which occurs against infection, toxic chemical, injury and tissue damage. It is a part of … Read more

Innate Immunity – Definition, Types, Mechanism, Functions

• • 3 revisions • 40 min readby
Innate Immunity

Innate immunity is the natural defence system of the body which is present from birth. It gives immediate protection against invading pathogens like bacteria, viruses, fungi and parasites. It acts in a non-specific manner and does not require previous exposure to the antigen. Innate immunity is the first and primary defence system of the body … Read more

Nosocomial Infection – Prevention, Source, Transmission

• • 19 min readby
Nosocomial Infection

A nosocomial infection, also known as a hospital-acquired infection, is an infection that a patient contracts during the course of receiving treatment for another condition in a healthcare setting such as a hospital, nursing home, or clinic. Nosocomial infections have been a significant problem throughout history, with reports of healthcare-associated infections dating back to the … Read more

The Complement Pathway – Activation, Functions, and Deficiencies.

• • 10 min readby
The Complement Pathway

Hey, in this article I will discuss the complement pathway which is one of the easiest pathways. Basically, This complement pathway helps to kill microorganisms  by antibodies or phagocytosis. The complement pathway has been accomplished in three main ways, which I have discussed step by step below. Believe me, if you understand the first step … Read more