lmmunology

Immunology
Dr.Baha.Hamdi. AI-amiedie
Ph.D.Microbilogy
The origin of the immune concept .The term Immunity is latin word immunitas is protection from legal prosecution. Biological definition is protection from infectious disease
The scientific view of immunity = Edward Jenner (1796) :observation of milkmaids generally get no smallpox.
Hypothesis= vaccinia ,pus from (box) protact milkmaids fro smallpox,so the immne concept " immunity" developed gradually through many scientific findings:
Robert Koch (1905 Nobel laureate) Infectious disease caused by microorganisms
Louis Pasteur : vaccines against cholera & rabies. The clinicall successs facilitate the search of underlying mechanisms of " protection of infectious disease" The developing of " lmmunology " advances in technology ( cell culture. Monoclonal Ab, Fllow cytometry, Genetic engineering…) have facilitated our understanding of immune system the functions
Non-Specific defense mechanisms: It is an inherent resistant present in the host body they are present as normal component in the body they are not induces by exposure to infection. There are different determinates affected this immunity:
A-Host determinant:(1-Age 2-Hormones& Nutritional 3- Genetic back ground (Heredity)).
B-Physical determinant( as membrane barrier ,Moist surface: skine is the first defenace against infections Agent consisting keratinized outer layer also secretion of sweat, sebaceous, fatty acid, tears.
C-Active antimicrobial determinant: Mucus: it is coats the epithelial cell of mucosa which trapped microbe & remove it with different mechanism:
1-Cillia in respiratory tract. 2- Coughing& Sneezing in respiratory tract. 3-flashing reaction of saliva & tears . Also skine secretion of sweat & sebaceous which is antifungal and antibacterial & mucus membranes of antibacte.rial & antivirus secretion.
Phagocytosis & digestion: (Antimicrobial substances of tissue fluids e.g lyzoymes, basic polypeptide phagocytosis & digestion. Macrophage it is either monocytes or polymorph nuclear leucocytes(PMN) which are present in peripheral blood or in tissue.
The main function is to phagocytosis & digestion & distraction the invader microbes.
There are Varity of molecules which react with different microbes:
1-Acut phase protein. 2-Complement system 3-Cytokines.
Interferone: the important cytokine of non-specific immunity is interferon(INF).
Interferone: It is a family of cytokines produce by wide Varity of cells such as fibroblast, macrophages & the epithelial cell they induce by viruses which block the virus invade
From infected neighbor cell of the host.
Innate immunity: first line of defense : penetration of the epithelial surface cell of the body by microorganisms ( e.g bacteria) engulfment of microorganisms by macrophages, neutrophils, dendritic cell release cytokine & chemokine s " inflammation"
Adaptive ( acquired) immunity: takes time to develop hum oral immunity ( antibody-mediate specific immunity) or cell mediated immunity (the aspect of adaptive immune response where antigen-specific T- cell have the man role)
Antign: substance cause the immune response when it introduce into host body,Antigen have the following characters:
1-have large molecular weight 10.000 Daltons or more
2-It should have large surface area
3- It should specificity: this specificity due to antigenic determination (epitopes) which is surface located with certain sequence in astrochemical structure of substances
4-chemical complexity: Antigen should have great degree of complexity, protein are the most potent immunogenic because there dimension of structure
5-forigenes: Antigen should be foregone to the host makes contact with it . so it should recognize when introduce into the human host, or experimental animals,
Immunogenic: it is substances foreign to the host immune system there for any microorganisms get into the body host and it is forigen to the body host so it recognize by the cell immune system & it induce the immune response.
One must differentiate between the antigen which react ( in vitro) with product of the immune system & the immunoge which induce the immune response lead to produce the antibody or T- cell lymphocytes sensitize their productes.
Haptine: substances with multi- determinates as Allergens molecules can note initiate the immune response but react with the product with immune response e.g drugs may adsorbs on surface of R.B.C stimulating this will result hemolytic disease & lysis
R.B.C cells.
immunological Adjuvants: substances add to the antigen or vaccine to stimulate& enhance the immune response, lnorganic gell. Alamin salt : it the sole Adjuvante acceptable for the human vaccine.









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