Immunology

Immunology is a part of biology that includes the study of immune systems in all the living organisms. It encompasses the study of anatomy functions, development, and malfunctions of the immune system. All these studies are very important to understand human diseases.

Immune SystemImmune System

Immune System consists of different types of cells and molecules which protect our body against pathogens. Pathogens are defined as everything from parasites to fungi, bacteria, viruses, and haptens. Haptens are molecules that may cause an immune response when comes in contact with a protein. All these cells and molecules are distributed in all the tissues of the body as well as lymphoid organs which eliminate or prevent microbial infections to decrease the growth of tumors and starts the repairing process of damaged tissues.

The tissues and organs of the immune system act as security forces where cells act as the security guards while molecules act as the guns & bullets and use the communication system to protect you.

Innate and Adaptive Immune System

Immune System fights against microbes and is divided into different types of reactions:

  • Innate Immune System
  • Adaptive Immune System

Innate Immune System

Innate Immune System is composed of cells and proteins that are present and always ready to fight against microbes in the infection area. Main elements of the innate immune system are –

  • Dendritic cells.
  • Phagocytic leukocytes.
  • Natural killer (NK) cell.
  • Physical epithelial barriers.
  • Circulating plasma proteins.

Adaptive Immune System

Adaptive Immune System

The Adaptive Immune System is required to fight against pathogens that can control innate immune defenses. All the components of the adaptive immune system are generally inactive however when activated; these components adjust to the presence of all the infectious agents by proliferating and developing a potent mechanism for eliminating the microbes.  Two Types of adaptive responses are – humoral immunity moderated by antibodies which are developed by B lymphocytes and cell-mediated immunity, moderated by T Lymphocytes.

Immunology and Diseases

Normally, disease occurs because of fundamental defects in the immune system. In this situation, the immune system is challenged and evoke responses that damage cells and tissues rather than protecting. All the immunodeficiency diseases increase the risk of tumors and infections and are caused by malnutrition, gene mutations, and viruses – HIV.

Symptoms of Immune Dysfunction

  • Frequent colds and flu.
  • Candida overgrowth.
  • HPV and abnormal PAP smears.
  • Allergies and Asthma.
  • Psoriasis, eczema, hives or rashes.
  • A rhinitis or a constant runny nose.
  • Autoimmune disorders.
  • Painful joints and muscles.
  • Parasite infections.
  • Bowel disorders.
  • Herpes (cold sore) outbreak.

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