Human Immunity and Blood

An autoimmune disease is a condition arising from an abnormal immune response to normal body tissue. In an autoimmune disease, the immune system fails to recognize self-cells and produces antibodies against self-cells. Common symptoms include low-grade fever and feeling tired. Autoimmune disease is due to genetic abnormality or other environmental factors. 

Autoimmune diseases are disorders in which the bodys immune system attacks the body's own cells and organs with proteins called autoantibodies; this process is called autoimmunity. The bodys immune system normally makes large numbers of proteins called antibodies to help the body fight off infections. In some cases, however, the body makes autoantibodies. Examples include systemic lupus erythematosus (SLE), Sjgren's syndrome, Hashimoto's thyroiditis, Graves' disease, idiopathic thrombocytopenic purpura, Addison's Disease, rheumatoid arthritis (RA), polymyositis (PM).

Neutrophils and lymphocytes are types of white blood cells (leukocytes) that are produced in the red bone marrow through the process of hematopoiesis.

Bones and blood are connective tissues (mesodermal origin), serum is plasma without clotting factors, there are five types of leucocytes (neutrophils, eosinophils, basophils, lymphocytes, monocytes), and osteoblasts form bone. All statements are correct.

• Lymphokines are a typer of cytokines which are secreted by the lymphocytes (immune cell).
• They are a type of small proteins secreted by cells of the immune system that helps in signalling and effects the behaviour of the neighbouring cells.
• Lymphokines attract the other cells of the immune system such as macrophages and other lymphocytes to an infected site and activate them to prepare for an immune response. 
• They are secreted by the T-lymphocytes.
• Lymphokines help the B- lymphocyte cells to produce antibodies.
• Interferon is a lymphokine secreted by the T-lymphocytes which are responsible for innate and adaptive immunity against viruses, few bacteria and protozoa.
• It is known as Interferon-gamma (IFNγ).
• It inhibits viral replication by its immunostimulatory and immunomodulatory effects.
  
• So, the correct answer is 'Interferon'.

• When the immune system is activated due to the viral infection or other immune response the white blood cells in our body produces Interferons (are a group of proteins called cytokines).
• The name of the interferons comes from their ability to interfere with the production of new virus particles. Interferons do not directly kill viral or cancerous cells; they boost the immune system response and reduce the growth of cancer cells by regulating the activity of several genes that control the secretion of numerous cellular proteins that affect growth.
• Hence a cell coded protein formed in response to infection with most animal viruses is interferon.
• So, the correct answer is 'Interferon'.

• Interferons are a group of signalling proteins made and released by host cells in response to the presence of several viruses. Generally, a virus-infected cell will release interferons causing nearby cells to make their anti-viral defences.
• A paratope also called an antigen-binding site or Fab. It is a part of an antibody which recognizes and binds to an antigen. It is a small region of the antibody containing the antibody's heavy and light chains.
• Interleukins (ILs) are a group of cytokines (secreted proteins and signal molecules) that were first seen to be expressed by white blood cells (leukocytes).
• Histamine is an organic nitrogenous compound involved in local immune responses, as well as regulating physiological function in the gut and acting as a neurotransmitter for the brain, spinal cord, and uterus. Histamine is involved in the inflammatory response and has a central role as a mediator of itching.
• So, the correct answer is 'a-iii,b-i,c-iv,d-ii'.

Interferons (IFNs) are a group of signaling proteins made and released by host cells in response to the presence of several viruses. In a typical scenario, a virus-infected cell will release interferons causing nearby cells to heighten their anti-viral defenses. Interferons are a group of proteins called cytokines produced by white blood cells, fibroblasts, or T-cells as part of an immune response to a viral infection or other immune trigger. The name of the proteins comes from their ability to interfere with the production of new virus particles.

In the last fifteen years the role of cytokines in the modulation of anti-tumor responses has been extensively studied at the Institute of Microbiology of the University of Turin. In retrospect many observations appear to have been quite innovative and original. Altogether they form the steps of a consequential intellectual endeavour leading progressively towards a precise definition of the role of the lymphokines in modulating the immune response to neoplasia. Starting from the characterization of the tumor signals required for lymphokine induction, this research progressed towards the definition of the cellular, molecular and genetic mechanisms involved, and provisionally ends with the direct manipulation of lymphokine genes transfected to tumor cells.

Type II hypersensitivity involves antibodies (IgG or IgM) binding to antigens on cell surfaces, leading to complement activation or phagocytosis.

Type II hypersensitivity is characterized by cytotoxic reactions where antibodies bind to antigens on the cell surface.

IgE antibodies are called cytotropic because they have a high affinity for receptors on the surface of mast cells and basophils.

In Type II hypersensitivity, antibodies bind to the cell surface (a), which then activates the complement cascade (c), leading to opsonization and phagocytosis (b), and finally cell death (d).