November(2015( 1( anus( DEUTEROSTOME+ mouth+ PROTOSTOME+ VERTEBRATES+ GNATHOSTOMES( Petromyzon( AGNATHANS( HEMICHORDATES+ ECHINODERMS+

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Erik Robbins
5 years ago
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of food consists of the tissues of other

nourishment, certain organisms can learn

Immunity denotes the resistance which an

1 November2015 1! At some stage of evolution one or more species must have made the momentous discovery that a very convenient source of food consists of the tissues of other organisms. And whatever the first form of life on earth may have been we find at the present time that all organisms have provided themselves with some membrane or shield to protect themselves against invasion from the outside.!! William C Boyd, Fundamentals of Immunology 1956! Boris I. Kuperman and Victoria E. Matey,2000 h/p:// GNATHOSTOMES AGNATHANS Petromyzon VERTEBRATES It was probably not very late in the history of evolution that another and about equally important discovery was made. Instead of simply eating other individuals and thus obtaining nourishment, certain organisms can learn to live with or upon other organisms and obtain theire nourishment, either by eating portions of the tissues or by absorbing food which would otherwise be utilized by the host. Immunity denotes the resistance which an organism offers against aggression by a parasite. The study of immunity is only a branch of biology and it could even be maintained that it is only a branch of ecology. W. Boyd Op. cit. anus DEUTEROSTOME mouth PROTOSTOME CEPHALOCHORDATES Branchiostoma UROCHORDATES Ciona HEMICHORDATES ECHINODERMS Strongylocentrotus PLATHYHELMINTHS ANNELIDS MOLLUSKS Biomphalaria NEMERTEANS SIPUNCULIDS NEMATODES INVERTEBRATES ARTHROPODS Anopheles Drosophila Penaeus1 CNIDARIA Protozoa PORIFERA PLACOZOA

Early in evolution of Metazoa: the context

immune systems Should have diversity and

down regulation) Many solutions Innate and

and eliminating specifically the danger i.

Simultaneous threats: Viruses, Bacteria,

Should confer to each individual within a

do-ityourself kit. Memory could be useful.

life span, progeny size, early development

) Original diversity of immune mechanisms,

immunity Intracellular: NLR,TRIMs, RIG1-L

2 Early in evolution of Metazoa: the context Selective pressures and constraints on the immune systems Should have diversity and flexibility, should be regulated up and down regulation) Many solutions Innate and adaptive: gene families, many molecular categories, Treg. Should be rapid and efficient at detecting and eliminating specifically the danger i.e keeping symbionts, eliminatin pathogens, dealing with generation gap) Innate components, constitutive elements. Simultaneous threats: Viruses, Bacteria, Archea, fungi, individuals of the same species, variants of self. Simultaneous responses: Physical barriers, RNA interference, restriction, intracelluar mechanisms. Surface receptors. Should confer to each individual within a species the best chances of survival under often rapidly) changing environment conditions. Somatic adaptations. Should be economical i.e. should not use too much genetic material, too many cells. Somatic adaptations, combinatorial usage of elements. Inheritance of adaptive systems as a do-ityourself kit. Memory could be useful. Clonal selection unicommitted lymphocyte), CRISPRs. Modulations of the above under the influence of life histories of the organisms are likely: temperature, size, life span, progeny size, early development properties etc. ) Original diversity of immune mechanisms, receptors and effectors Cell autonomous immunity Intracellular: NLR,TRIMs, RIG1-L etc. Should not react with self. Clonal selection lymphocyte). Central tolerance. Peripheral tolerance. Constitutive soluble elements: Complement C ), PPO, clotting e.g.. Inducible cellular responses: Receptor Signalling Effector often articulated around conserved domains and conserved signal transduction cascades LRR IgSF Lectin SRCR Fn3 EGF C PGRP TIR Gnathostomata Agnatha Urochordata * Cephalochordata Echinodermata Lophotrochozoa Ecdysozoa ** Cnidaria Porifera Protozoa Plants Sponges and sea fans Highly polymorphic histocompatibility loci J.Theodor GRP

ComparaHveapproaches InformusaboutevoluHon DiscoveryofmanysimilariHes Homologies AstateofsimilarityinstructureandanatomicalposiHonbutnotnecessarilyinfuncHon

3 ComparaHveapproaches InformusaboutevoluHon DiscoveryofmanysimilariHes Homologies AstateofsimilarityinstructureandanatomicalposiHonbutnotnecessarilyinfuncHon betweendifferentorganismsindicahngacommonancestryorevoluhonaryorigin Taketheimmunesystemofmanandlook inotherspecieswhathasbeenconservedsequencecomparison): IthelpsdeterminingwhatisessenHalandwhatisaccessory Homologyrevealstheadvantagesofagivenslectedstructure MostelementsconservedsincePorifera Analogies StructuralorbehaviouralsimilarityintermsoffuncHonsbetweenunrelatedspeciesororganismsbut thatdonotshareacommonancestralordevelopmentalorigin FollowthesoluHonsselectedfromunicellularorganismstoVertebratesaQer anexposuretoapathogen AnalogiesrevealthestrengthofselecHonpressures FlajnikandDuPasquier2004

4 PhagocytosisinMonocellularorganisms DiploblasHcMetazoa Epithelialimmunity TriplobasHcMetazoa Macrophages,lymphocytesandalike Divisionofthework MASP=mannoseCassociatedserineprotease1 Science.2007Aug3; ): Dictyostelium1 Copyright,M.J.Grimson&R.L.Blanton.BiologicalSciencesElectronMicroscopyLaboratory,TexasTechUniversity DictyosteliumsenHnelcellshavingabsorbedethidiumbromidered)

5 LRR)TLR/IgSF)IL1R TIR ScavR.MannoseR.LecOnR. Intracellularsystems RIG1,PKR,NLR,TRIM NK Effectors:AMP,Cytokines, AID RAG TCBIgSF APC MHCpres. Thymus,BM, Randomrep.select. ClonalselecOon Effectors:Abs,CTLs,TChelp specificity,memory regulaoon AffinitymaturaOon Coreceptors CosOmulators FcreceptorsITIM Cytokines Chemokines INNATE,adaptaOonduringevoluOon ADAPTIVE,adaptaOonduringone slife PDC TypeIIFN Acutephase Pentraxins Epithelia MacrophagesGranulocytes C Lymphocytes Lymphoidorgans AconstellaOon: manymodules notnecessarilylinkedtooneanother Immunityinman Liver Phagocytosis Asystem: Centeredonlymphocytes lockedinacoevoluoonaryunit Tocreateistorecombine FrançoisJacob Toborrowisbest RobertJack

Lymphocyte lineages The lymphocyte surface without the an7gen receptor

2 Lymphocyte lineages The lymphocyte surface without the an7gen receptor INNATE, adapta6on during evolu6on ADAPTIVE, adapta6on during one s life Liver Epithelia Macrophages Granulocytes Acute phase Pentraxins