Question

1. Describe the difference between innate and adaptive immunity

2. Describe what happens in an inflammatory response.

3. What is the purpose of a vaccine ?

Answer 1

1. Describe the difference between innate and adaptive immunity

ANSWER :

Immunity can be defined as body 's defense mechanism against pathogens.Body quickly response by recognizing and fighting against them.

INNATE IMMUNITY Also known as natural or native immunity Defense mediated by early reaction Consist of cellular and biochemical defense Specific for structures common to group of related microbes. Components Physical and chemical barriers, such as epithelia and antimicrobial chemicals produced at epithelial surfaces; Phagocytic cells (neutrophils, macrophages), dendritic cells, and natural killer (NK) cells and other innate lymphoid cells; Blood proteins, including members of the complement system and other mediators of inflammation.

ADAPTIVE IMMUNITY Also known as specific or acquired immunity. Activated when innate immunity fails. Helps to recognize and react to large number of microbial and non microbial substances. More specific Provides the body with the ability to recognize and remember specific pathogens(memory of previous exposure) through their antigens. Components: lymphocytes and antibodies

2. Describe what happens in an inflammatory response.

ANSWER :

Inflammation is defined as response of the body's vascularized tissues to harmful stimuli such as infectious agents, injuries, chemical irritants, etc.

The normal immune response have four main components: Pathogen recognition The innate immune system triggers an acute inflammatory response Activation of specific T helper cells. CD4 helper T cells then co-ordinate a targeted antigen-specific immune response involving two adaptive cell systems: humoral immunity from B cells and antibodies, and cell-mediated immunity from cytotoxic CD8 T cells.

Features of this process are: Vasodilation and increased blood flow –erythema (“rubor”) and warmth (“calor”) Increased vascular permeability – this allows an inflammatory cell infiltrate to extravasate and reach the site of infection, and also causes tissue oedema and swelling (“tumour”) Release of inflammatory mediators -such as bradykinins and prostaglandins which increase pain in the infected area (“dolor”) Neutrophil chemotaxis – neutrophils migrate to the site of infection and phagocytosing pathogens and debris Microvascular coagulation – this is induced by local tissue damage, and acts to confine the infection and prevent its spread

Systemic manifestations such as fever and raised inflammatory markers such as CRP and ferritin – this produces unpleasant “flu-like” symptoms such as hot flushes, sweats, chills, rigors, headache, nausea, myalgia, arthralgia and fatigue.Upregulation of costimulatory molecules such as MHC-II and B7 to encourage activation of the adaptive immune system.

3. What is the purpose of a vaccine ?

ANSWER :

Vaccine is a biological preparation of weakend, inactive or killed form of a microbial agent, toxin or surface protein on its surface ,or even genetically engineered antigens ,which can causes infectious diseases.
Vaccines prime our immune system to recognize and fight against pathogens like viruses, bacteria etc to keep us safe from disease.

PURPOSE OF VACCINE:

1. PROVIDE HERD IMMUNITY .
2. BOOST IMMUNE SYSTEM DEFENSIVE MECHANISM OF BODY
3. PROTECT INDIVIDUAL FROM DISEASE
4. PROTECT COMMUNITY FROM SPREAD OF DISEASE
5. REDUCE SEVERITY OF DISEASE
6. HELPS TO ERADICATE DISEASE