Immunology And Serology - Carter Center

LECTURE NOTESFor Medical Laboratory Technology StudentsImmunologyand SerologySelamawit DebebeAlemaya UniversityIn collaboration with the Ethiopia Public Health Training Initiative, The Carter Center,the Ethiopia Ministry of Health, and the Ethiopia Ministry of Education2004

Funded under USAID Cooperative Agreement No. 663-A-00-00-0358-00.Produced in collaboration with the Ethiopia Public Health Training Initiative, The CarterCenter, the Ethiopia Ministry of Health, and the Ethiopia Ministry of Education.Important Guidelines for Printing and PhotocopyingLimited permission is granted free of charge to print or photocopy all pages of thispublication for educational, not-for-profit use by health care workers, students orfaculty. All copies must retain all author credits and copyright notices included in theoriginal document. Under no circumstances is it permissible to sell or distribute on acommercial basis, or to claim authorship of, copies of material reproduced from thispublication. 2004 by Selamawit DebebeAll rights reserved. Except as expressly provided above, no part of this publication maybe reproduced or transmitted in any form or by any means, electronic or mechanical,including photocopying, recording, or by any information storage and retrieval system,without written permission of the author or authors.This material is intended for educational use only by practicing health care workers orstudents and faculty in a health care field.

Immunology and SerologyPrefaceImmunology and serology is an advanced science dealingwith how the human immune system organized, function andthe different types of serological techniques. It is a very vastsubject covering a wide area of technology.The shortage of reference materials in the area and in orderto present the subject in a relatively simplified and organizedway called the need for preparing a lecture note.This teaching material is prepared based on the existingcurriculum of immunology and serology and consists of 16chapters. Each chapter has its own objective, body andquestions (exercises) at the end. Therefore, the material isdesigned to present clear and concise understanding aboutimmunology and serology; and it is primarily suitable forstudents following diploma programme in medical laboratorytechnology.Finally, it is quite obvious that it had demanded a lot of effortin preparing this material. However, it should be noted thateven then, there could be constructive comments which arehelpful in improving this lecture note.Thus, it will be wellaccepted and acknowledged for the contribution.i

Immunology and SerologyAcknowledgmentsI would like to acknowledge The Carter Center initiative forsupporting the preparation of this lecture note.My deepest appreciation also goes to Alemaya UniversityFaculty of Health Sciences staff who have an input in one oranother way.I am also very grateful to medical laboratory technology staffof JU, DCTEH, GCMS, for their valuable comments and ideasin revising the first draft.Finally, I wish to extend my thanks to W/t AschalechTemesgen for writing me the draft of this lecture note.ii

Immunology and SerologyAbbreviationsCRP-C-reactive ProteinEBV-Epstien-Barr VirusEIA-Enzyme Immune AssayHCG-Human Chorionic GonadotrophinPMN-Polymorphonuclear Leukocytesiii

Immunology and SerologyTable of ContentsPrefaceAcknowledgementAbbreviationsTable of ContentsCHAPTER ONE: INTRODUCTION TOIMMUNOLOGY-SEROLOGY1.1 Historical back groundCHAPTER TWO: IMMUNITY2.1 Definition of immunityCHAPTER THREE: THE LYMPHOID SYSTEM3.1 Lymphoid tissue3.2 The lymphocytesCHAPTER FOUR: THE ANTIGEN, ANTIBODIESAND THE COMPLEMENT SYSTEM4.1 Antigen4.2 Antibodies4.3 Immunoglobulin4.4 Complement systemiv

Immunology and SerologyCHAPTER FIVE: THE CELLULAR IMMUNITY5.1 Cell mediated immune response5.2 delayed type of hypersensitivity5.3 Autoimmune diseaseCHAPTER SIX: ANTIGEN- ANTIBODYINTERACTION6.1 Principle of antigen antibody interaction6.2 In vitro antigen antibody reaction6.3 Factor affecting antigen antibody reactionCHAPTER SEVEN: SEROLOGICAL TECHNIQUES7.1 Materials necessary for basic serology tests7.2 Collection, preparation and preservation ofspecimen for serologic test7.3 Shipment of serologic specimen7.4 Complement inactivation7.5 Serial dilution7.6 determinations of end point and titerCHAPTER EIGHT: SYPHILIS SEROLOGY8.1 Treponematoses8.2 Syphilis8.3 Tests for syphilisv

Immunology and SerologyCHAPTER NINE: AGGLUTINATION TEST FORFEBRILE DISEASES9.1 Typhoid and paratyphoid fever9.2 Rickettsial diseases9.3 Brucella abortusCHAPTER TEN: HUMAN CHORIONICGONADOTROPIN HORMONE10.1 HCG and pregnancy10.2 Pregnancy test10.3 Specimen collection10.4 Factors affecting pregnancy testsCHAPTER ELEVEN: HUMANIMMUNODEFICIENCY VIRUS11.1 Disease characteristics and clinicalmanifestation11.2 Laboratory diagnosisCHAPTER TWELVE: HEPATITIS VIRUSCHAPTER THIRTEEN: C-REACTIVE PROTEINCHAPTER FOURTEEN: INFECTIOUSMONONUCLEOSIS14.1. Epistien-Barr Virusvi

Immunology and Serology14.2 hetrophil antibodies14.3 Serological testsCHAPTER FIFTEEN: STREPTOLYSIN OCHAPTER SIXTEEN: RHEUMATOID FACTORGLOSSARYBIBLIOGRAPHYvii

Immunology and SerologyCHAPTER ONEINTRODUCTION TO IMMUNOLOGYSEROLOGYAt the end of this chapter, the reader should be able to:-Define the term immunology-Describe the historical background of immunology1.1 Historical Background of ImmunologyImmunology is defined as the study of the molecules, cells,organs, and systems responsible for the recognition anddisposal of foreign material. Immunology began as a branchof microbiology. The study of infectious disease and thebody’s response to them has a major role for the developmentof immunology. More over, the concept of germ theory ofdisease has contributed to the field of immunology.It was Edward Jenner who first studied the response of thebody to foreign substances. He observed that dairy maidswho had naturally contracted a mild infection called cowpoxseemed to be protected against smallpox, a horriblydisfiguring disease and a major killer.1

Immunology and SerologyIn 1796, Jenner inoculated an eight year-old boy with fluidfrom cowpox blisters on the hand of a dairymaid. The boycontracted cowpox. Then two month later Jenner inoculatedhim with fluid from a small pox blister, the boy only developeda small sore at the site of inoculation. His exposure to the milddisease cowpox had made him immune to the small poxinfection. These were some of the vital events occurred in thehistory of immunology following Jenner’s achievement.In 1879, the first human pathogen, gonococcus, was isolatedby Neisser. In 1883, Klebs and Loeffler isolated diphtheriabacilli which led to the production of the first defined antigen,diphtheria toxin, by Roux and Yersin in 1888. In the sameyear the first antibodies, serum bactericidins, were reported byNuttal and Pasteur.In 1890, von Behring and Kitasato discovered antitoxins thatled to the development of toxoids for diphtheria and tetanus.In 1900, Land Steiner discovered the blood group antigensand their corresponding antibodies. This led to the ability togive blood transfusion with out provoking reactions. It was in1916 that the first journal of immunology began publication inwhich many of new findings published on it. In general,immunology has always depended on and stimulated theapplication of technology, such as the use of ce,2etc.Thus

Immunology and Serologyimmunology has not become an inborn discipline but hasmaintained close associations with many other fields ofmedical sciences.3

Immunology and SerologyReview Questions1. Who was the first person studied the body’s response toforeign substance?2. Describe the development of the field immunology3. What was the contribution of Land Steiner for the field ofimmunology?4

Immunology and SerologyCHAPTER TWOIMMUNITYLearning ObjectivesAt the end of this chapter, students are expected to:-Describe the different types of immunity-Explain the role of the immunity in defense mechanism-Discuss factor that affect the immunity2.1. DefinitionImmunity can be defined as the way in which the body canprotect itself from invasion by pathogenic microorganism andprovide a defense against their harmful effect.Immunity is classified in to two major groups-Non specific immunity-Specific immunity2.1.1. Non specific (natural or innate) immunity.Non-specific immunity, also called natural or innate immunity,is the first line of defense against any infectious agent. Nonspecific host responses provide an effective barrier that5

Immunology and Serologyprevents the microorganisms from penetrating, inhibit ordestroy the invader if it gains access to the tissues, andeliminate or neutralize any toxic substance elaborated byinfectious agent. Several mechanisms are available in theimmunocompetent host. These include physical or mechanicalbarrier, biochemical factors, cellular mechanism, role ofnormal flora & inflammatory reactions.Physical or mechanical barrierThe unbroken skin and mucus membrane are effectivemechanical barriers to infectious agents. The surface of theskin is also inhibitory to the growth of most microorganismsbecause of low moisture, low pH, and the presence ofsecreted inhibitory substance. However, it is possible forsome microorganisms to enter the skin through hair follicles,sebaceous glands or sweet glands.Similarly, mucus membranes consist of an epithelial layer andan underlying connective tissue layer. They line the entiredigestive, respiratory, urinary, and reproductive tracts. Forexample, the epithelial surface that lines the nasal cavity andthroat are protected by a combination of mucous productionand cilliary movement. Because mucous is so viscous,microorganisms adhere to it. Epithelial cells with ciliaconstantly move the mucus layer to ward the mouth, where it6

Immunology and Serologyalong with the trapped microorganism is swallowed andeliminated.Besides, the action of coughing removes mucus that containsmicroorganisms. In the urethra rapid flow of urine washesaway most microorganisms. Tear that wash the conjunctivaperform a similar defensive function.Biochemical factorsThese are chemical secretions produced by the body thatinhibit microbial growth. The following are included as anexample, keratin is a skin protein produced by the outher mostcells of the skin, since it has very little water, the skinbecomes very dry and therefore to most species ofmicroorganism. The growth of microorganisms is inhibited inthe gastrointestinal tract by hydrochloric acid and bile salt,which are secreted by the stomach and liver, respectively.Lysozyme is an enzyme found in many body fluids andsecretions such as tears. It can break down the cell wall ofGram-positive bacteria and a few gram-negative bacteria byhydrolyzing the peptidoglycan layer.Complement is a family of more than twenty different proteinsin serum that function as a non-specific defense againstinfection.7