Nonspecific and Specific Immunity PDF

Nonspecific and Specific Immunity By: Dr. Glory E. Mbah  THE IMMUNE RESPONSE AND IMMUNITY Immune response – Innate (non-specific) – Adaptive or Acquired (specific) 2  Defense Mechanisms Immunity State of non-sp...

Nonspecific and Specific Immunity By: Dr. Glory E. Mbah  THE IMMUNE RESPONSE AND IMMUNITY Immune response – Innate (non-specific) – Adaptive or Acquired (specific) 2  Defense Mechanisms Immunity State of non-specific and specific protection Nonspecific defense mechanisms Specific defense mechanisms (immune system) First line of Second line of Third line of defense defense defense Skin Phagocytic white Lymphocytes Cilia blood cells antibodies Physiological The inflammatory factors response Antimicrobial substances 3  Nonspecific (Natural , Innate) Immunity: first line of defense Composed of structural barriers to keep infectious agents out of the body. – Intact skin – Cilia – Physiological factors. 4  Intact Skin Difficult for a pathogen to penetrate, – Composed from closely packed cells, multiple layering, contanious sheding of cells, Presence of keratin. – Sweat creates high salt conditions, antibacterial enzyme (lysozyme). – Oil layer, fatty acids and acid pH present makes an inhospitable environment for microorganisms. Normal flora prevent other microorganisms from establishing an infection – “competitive exclusion”. 5  Body Coverings: The Skin epidermis sebaceous glands sweat gland 6  Respiratory Tract Upper Respiratory Tract – Nasal hairs induce turbulence – Mucous secretions trap particles – Mucous stream to the base of tongue where material is swallowed – Nasal secretions contain antimicrobial substances – Upper respiratory tract contains large resident flora Lower Respiratory Tract – Particles trapped on mucous membranes of bronchi and bronchioles – Beating action of cilia causes mucociliary stream to flow up into the pharynx where it is swallowed – 90% of particles removed by this way. Only smallest particles (