课件分析免疫学

1、课件下载地址 参见链接：2014临床医学五年制医学免疫学课件验证码：1234Antibody(Ab)ContentThe structure of immunoglobulinsFunction of immunoglobulinsHeterogenecity of Ig Characteristic and function of Different class of Ig Monoclonal antibodyIntroduction Antibody(Ab) - protein produced by plasma cells in response to immunization an

2、d binds specifically to particular Ag. -Ab is generally defined in terms of their specific binding to the immunizing Ag 1854-1917Nationality:GermanyFields:Physiology and immunologyKnownfor Diphtheria vaccine Nobel Prize in Physiology or medicine (1901) for “ Antitoxin immunity” theory IntroductionIn

3、troductionIntroductionImmunoglobulins (Ig) - The Igs are globulin which function as Abs or similar to Abs in chemical structure. - secreted Ig(sIg) ;membrane Ig(mIg)Structure of the AbH and L chainV and C RegionHinge regionDomainJ chain and SPIg FragmentRodney Porter Gerald Edelmanfor their discover

4、ies concerning the chemical structure of antibodiesStructure of the Ab1.Heavy Chain and Light Chain heavy chain (H chain) 5075Kd 450550aa H chain: isotype:IgM, IgG,IgA,IgE, IgD IgG:IgG14 IgA:IgA1 ,IgA2 Structure of the AbStructure of the Ab1.Heavy Chain and Light Chain light chain (L chain) 25Kd 214

5、aa classes of L chain: : 1 42.variable region and constant region variable region(V region) Light Chain - VL (110 aa) Heavy Chain - VH (110 aa) HVR or CDR FR Structure of the AbHVR or CDRHVR: hypervariable regions CDR: the complementarity determining regions. CDR are found in both the H and the L ch

6、ains.Idiotype: Antigen Determinant of IgStructure of the AbFramework regionsFR (framework region) regions between the CDR in the V region are called the FR. VL and VH: Ag binding siteStructure of the Ab Constant region (C region) Light Chain - CL (110 aa) Heavy Chain - CH (330-440 aa) : CH1, CH2, CH

7、3,( CH4)Structure of the Ab3. Hinge Region - between the CH1 and CH2 region - rich in proline residues flexibility: allow the two Fab arms to bind epitopeStructure of the AbDomains of AbStructure of the AbStructure of the AbStructure of the AbJ chain and SP J chain (Joining chain)a ploypeptide chain

8、Join the momomer to polymerStructure of the AbStructure of the AbJ chain and SP Secretory piece(SP) Structure of the AbAb fragmentsStructure of the AbHeterogeneity of Ab1. Classification of Ig class subclass IgG1IgG4 type subtype 1 2 3 42. Diversity of Ig induced by exogenous factors3. Serotypes of

9、Ig induced by endogenous factorsIsotype The genes for isotype variants are present in all healthy member of a species.Heterogeneity of Ab(2) Allotype This refers to genetic variation between individuals within a species.Heterogeneity of Ab(3) Idiotype Variation in the V domain ,particularly in CDR,

10、produces idiotype.Heterogeneity of AbFunctions of AbFunctions of V region - recognition and binding to antigen - HVR (CDR) - sIgA 4; IgM 5 - neutralization of toxins;immobilization of microorganisms;neutralization of viral activityFunction of AbNeutralization of Toxin by IgGneutralization of viral a

11、ctivityFunction of AbFunction of C region1.activation complement:IgM,IgG1-3,IgA2.binding to Fc receptor of cellsopsonization A process by which phagocytosis is facilitated by the deposition of opsonins(Ab or C3b) on the antigen. Activation complementFunction of IgOpsonization of antibodyADCC (Ab-dep

12、endent cell-mediated cytotoxicity) A cytotoxic reaction in which Fc receptor-bearing killer cells recognize target cells via specific antibodies.IgE mediates type hypersensitivity.Function of immunoglobulins ADCC3.passage through the placenta(IgG) and mucosal(SIgA)Characteristic and function of Diff

13、erent class of IgIgGimmunoglobulina) IgG is the most important class of Ig in serum - 75% of serum Ig half-life in serum:23 daysb) Fixes complement IgG1-3 can while IgG4 can not IgG3IgG1IgG2IgG4c) crosses the placenta confers a high degree of passive immunity to the newborn.d) Binding to cells Macro

14、phages, monocytes, PMN and some lymphocytes Binding to SPAIgMimmunoglobulina) Penatmerb) IgM is the first Ig synthesized in life c) IgM is a good complement fixing Ig d) IgM is also a good agglutinating Ig e) IgM is mIgM ( IgD) of B cells :f) IgM is the first Ig produced in primary immune response.I

15、gAimmunoglobulinIgA : monomer and secretary sIgA exists in secretions such as tears, saliva, colostrum, mucus and has important role in local (mucosal) immunity.c) IgA can be transmitted from mother to newbornIgEimmunoglobulinIgE is the least serum Ig. b) Involved in typeallergic reactionsc) IgE pla

16、ys a role in parasitic helminth diseasesIgDimmunoglobulin IgD is found in low levels in serum; its role in serum uncertain.b) IgD is primarily found on B cell surfaces where it functions as a receptor for antigen. Membrane IgD disappear in actvated or memory B cellPreparation of Ab1) Polyclonal antibody2) Monoclonal antibody3) Genetic engineering antibodyimmunoglobulinMonoclonal antibody productionGenetic engineering antib