MUNI MED Genetics in Dentistry Gregor Johann Mendel Augustinián monastery in Brno (Czech Republic), May 2009 On the grounds of the abbey is the location of Mendel's garden and his green house. Gregor Johann Mendel, 1822-84, an Augustinián monk noted for his experimental work on heredity. He entered the Augustinián monastery in Brno (Czech Republic) in 1843. The Columbia Encyclopedia. Sixth Edition | 2008 Mendel was the first to fashion a clear, analytic picture of heredity. Genetics (genomics) in 21 st century ^Hypothesis: every disease has its own genetic predisposition, close or distant ^Arguments: • Every living being is fatal • Disease can be a state leading to death • Ageing can be a state leading to death • (Can be ageing considered a disease?) Genetics, genomics • genetics • specialised biological subject focusd on variability and heritability of life beings • Clinical genetics- diagnostics, therapy and prevention of monogenic disorders (genetics councelling • Cytogenetics • chromosomes • Population genetics genomics • Is focused on studies of structure and function of genome using special methods (genome mapping methods, sequencing et al.) Human genome • Human Genome Project (HUGO) • only-10%-coding sequences • -75% single sequences in one genome • Repetitive sequences • tandems • microsatelites • minisatelites • Alu-repettitions • LI-repetitions • mitochondrial DNA • Several tens of genes coding proteins involved in mitochondrial processes • Only maternal heredity! octomilka C. elegans človek ryže kukurice ***** ***** 911ft * * * • • ***** Mu: x: 11 e :ti:i Eiiii ..... ::::: 13,600 mit -9,500 ?0,0OO ■ 25,000 45,000 * * * * 50,000 Microsatellite or Short Tandem Repeat (STR) • Dispersed throughout genome • Core repeat length 2 - 7 bp • Up to -40 repeats per locus • Detected by PCR amplification Minisatellite or Variable Number of Tandem Repeats (VNTR) • Commonly subtelomeric ■ Core repeat length 8 - 80 bp ■ Variable total length of -OS to 30 kb • Detected by Southern hybridization Benefit of Human Genome Project 1. Faster Identification of Candidate Disease Genes: • Far more markers for mapping are available. • Candidate genes can be rapidly searched in the genome databases. • Mutational screens of candidate gene are greatly aided by information on the gene structure. 2. Faster Cloning of Genes of Interest by Homology Search in Genome Database: • Comparative Genomics • e-Cloning Label IT Get IT How many chromosomes are in a normal adult human cell? 46 pairs Match IT Gamete A structure that is made of DNA and is found in the nucleus Chromosome Where a characteristic is expressed if both copies are present Gene Sex cells such as sperm and egg Genotype The alleles present Phenotype A small section of DNA Dominant Where an allele is always expressed even if only one is present Recessive The two alleles are different Bb Allele Different form of the gene Homozygous The alleles that are expressed Heterozygous The two alleles are the same e.g. BB or bb Match IT - Answers Gamete Chromosome Gene Genotype Phenotype Dominant Recessive Allele Homozygous Heterozygous Sex cells such as sperm and egg A structure that is made of DNA and is found in the nucleus A small section of DNA The alleles present The alleles that are expressed Where an allele is always expressed even if only one _is present_ Where a characteristic is expressed if both copies _are present_ Different form of the gene The two alleles are the same e.g. BB or bb The two alleles are different Bb Basic terminology Dogma of molecular biology Centrální dogma DNA ^ RNA ^ Protein DNA do DNA -> REPLIKACE ONA do RNA -> TRANSKRIPCE RNA do Protein -> TRANSLACE RNA do DNA -> REVERZNÍ TRANSKRIPCE Jeden gen jeden enzym (protein/polypeptici) Human chromosomes • morphologically detected only during mitosis and/or meiosis when they are condensed • in diploid human cells -23 pairs of homologic and 2 sex chromosomes Human karyotype • 44XXnebo44XY • Germ cells (egg, sperm cell)- haploid • Structure of chromosomes • centromere • telomers • long-q • short - p 13 14 15 16 17 10 19 20 21 22 X Y Karyotype according to the Denver's classifications Synthesis of DNA in animal cells • DNA is stored in form of chromosomes. • Each chromosome contains 2000 origins of replication. From each this place synthesis of DNA can be realized in both directions. DNA is a linear sequence of bases joined together from their sugar moieties by phosphate groups DNA is a double helix Base pairings Sugar phosphate / backbone W Multiple choice quiz Get IT What is a gene? Something you get from one parent J r You have 23 pairs in the nucleus All of them Get IT Which pair of alleles represent homozygous? Structure of a gene INTRONS AND EXONS * Eukaryotic DNA differs from prokaryotic DNA it that the coding sequences along the gene are interspersed with non-coding sequences * The coding sequences are called • EXONS ona Operator _ Promoter I Regulatory i * The non coding sequences are called • INTRONS mRNA S' Active -— repressor (a) Lactose absent, repressor active, operon off lac operon Allolactose-^ Inactive (inducer) V repressor (b) Lactose present, repressor inactive, operon on Promoters DNA sequences that are recognised by transcription factors Transcription factors bind to this region and then start transcribing the DNA immediately downstream (5'-3J) Transcriptional Start Site (TSS) Double stranded » DNA SPl Single stranded 5' ^$$$$$$33 RNA Transcription Factors General Transcription Transcriptional Factors Activators Responsible for all Responsible for specific regulation transcription. Binds to RNA of transcription. Bind to DNA at polymerase and DNA at specific promoter sequences and generic promoter sequences activate RNA Polymerase TATA binding protein Human gene DNA 3- Promoter "1 Exon 1 Intron 1 E2 12 E3 13 Exon 4 3' 5' RNA •3' Transcription RNA transcript 1 I 2 I 3 I 4 - 3' 5'UTR Processing (capping, poly 3 UTR A adition, splicing) Mature mRNA Cap- -AAAAA n 5'UTR Protein NH ■2 * 1 'VT TTR ▼ Translation J UAa 2 3 4 -► COOH Crossing over: a/a Hi B AAJ* p E Gametes t |P||c I c C r <: 6 Chromatids change parts between homologous chromatids during the meiosis ■ Causes redistribution of heridary material between the homologous chromosomes Crossing-over and recombination during meiosis -> number of genes doesn't change -> new allele combinations are formed Chromosome and gene aberrations Chromosomal abnormalities Structural Numeric Gene mutatios Rare alleles Polymorphisms Chromosomal aberrations • aneuploidy (a difference in chromosome number) • meiotic non-disjunction • later -> somatic mozaicism • monosomy • gonosomal • Turner's sy. (45, XO) Low hairline • trisomy • autosomal Shield-shaped thorax • Down's sy. (47, XX/XY + 21) • Edwards's sy. (47, XX/XY+18) • Patau's sy. (47, XX/XY+13) Widely spaced nipples Shortened metacarpal IV Small finger nails • gonosomal • Klinefelter^ sy. (47, XXY) Brown spots (nevi) • polyploidy -letal Genomic disorders • Genomic disorders represent a clinically diverse group of conditions caused by gain, loss or re-orientation of a genomic region containing dosage-sensitive genes. • Determining how the copy number variation (CNV) affects human variation and contributes to the aetiology and progression of various genomic disorders represents important questions for the future. O'Driscoll M: Curr Genomics. 2008 May; 9(3): 137-146 Gene mutations as a cause of variability in genes • Rare alleles (prevalence less than 1% in population as a result of selection pressure and/or „recenf mutation). These mutations represent „great genetic factors" causing monogenic diseases - subjects of clinical genetics. • Polymorphisms (prevalence more than 1% in population, smaller genetic factors in interactions with environmental factors conditioning complex diseases - subjects of personalized medicine). Gene mutations as a cause of variability in genes • Mutations in somatic cells Sare generating in somatic cells during the lifetime ^are cell and/or tissue specific, without transfer to offspring • Mutations in germ cells ^they become components of genetic predisposition ^they are present in all cells of the individual ^they are transfered to offspring UNI ED Somatic cell mutations: an example Sporadic colorectal cancer Fertilized egg Gestation Infancy Childhood Adulthood Early clonal Benign Early invasive Late invasive ChereSfn?Py expansion tumour cancer cancer recurrence Intrinsic i — mutation processes O Passenger mutation ft Driver mutation a Chemotherapy resistance mutation Environmental t^^^m and lifestyle exposures Mutator m phenotype Chemotherapy 10s-1,000s of mitoses depending on the organ 3> 1-10 or more driver mutations 10s-100s of mitoses depending on the cancer 10s-100,000 or more passenger mutations T. .. . .t t. ...... , t. MR Stratton et al. Nature 458, 719-724 (2009) The lineage of mitotic cell divisions from the v ' fertilized egg to a single cell within a cancer showing the timing of the somatic mutations acquired by the +*\ Q fl 1 ff* cancer cell and the processes that contribute to lldLUlV them. UNI ED Figurative depiction of the landscape of somatic mutations present in a single cancer genome. Point mutation Interchromosomal rearrangement Intrachromosomal rearrangement Copy-number change MR Stratton et al. Nature 458, 719-724 (2009) Somatic cell mutations: an example Sporadic colorectal cancer nature Single Nucleotide Polymorphisms Protein Oty>Ali t SNPs GOC^G C No chuipja t Mochingo GOC > GQA T > A Gene mutation - types • Normal state • DNA • ATGCAGGTGACCTCAGTG • TACGTCCACTGGAGTCAC • RNA • AUGCAGGUGACCUCAGUG • PROTEIN • Met-Gln-Val-Thr-Ser-Val • Mutation „missense" • DNA • ATGCAGCTGACCTCAGTG • TA CGTCG A CTG G A GTC A C • RNA • AUGCAGCUGACCUCAGUG • PROTEIN • Met-GIn Leu Thr-Ser-Val Examples-hemoglobin S in sickle cell anemia-heterozygote advantage Gene mutation - types • Normal state • DNA • ATGCAGGTGACCTCAGTG • TACGTCCACTGGAGTCAC • RNA • AUGCAGGUGACCUCAGUG • PROTEIN • Met-Gln-Val-Thr-Ser-Val • Mutation „nonsense" • DNA • ATGCAGGTGACCTGAGTG • TACGTCCACTGGACTCAC • RNA • AUGCAGGUGACCUGAGUG • PROTEIN • Met-Gln-Val-Thr-Stop • Examples: ß° thalasemia Gene mutations- types • Normal state • DNA • ATGCAGGTGACCTCAGTG • TACGTCCACTGGAGTCAC • RNA • AUGCAGGUGACCUCAGUG • PROTEIN • Met-Gln-Val-Thr-Ser-Val • Mutation type of trinucleotide expanse • DNA • ATG(CAGCAGCAG)20CAGGTGACCTCAGTG • TAC(GTCGTCGTC)20GTCCACTGGAGTCAC • RNA • AUG(CAGCAGCAG)20CAGGUGACCUCAGUG • PROTEIN • Met-(Gln-Gln-Gln)20Gln-Val-Thr-Ser-Val • Examples: Huntington's disease Gene mutations- types • Normal state • DNA • ATGCAGGTGACCTCAGTG • TACGTCCACTGGAGTCAC • RNA • AUGCAGGUGACCUCAGUG • PROTEIN • Met-Gln-Val-Thr-Ser-Val • Mutation, type „frameshift" • DNA • ATGCAGGTGAACCTCAGTG • TACGTCCACTTGGAGTCAC • RNA • AUGCAGGUGAACCUCAGUG • PROTEIN • Met-Gln-Val-Asn-Leu-Ser • Examples: • Duchenn's muscular dystrophy, p° thalasemia, Tay-Sachs's disease Gene mutations- types • Normal state • DNA • ATGCAGGTGACCTCAGTG • TACGTCCACTGGAGTCAC • RNA • AUGCAGGUGACCUCAGU G • PROTEIN • Met-Gln-Val-Thr-Ser-Val Mutation: type Jnsertion" DNA ATGCAGGTG-3000 bp-ACCTCAGTG TACGTCCAC-3000 bp-TGGAGTCAC RNA AUGCAGGUG-3000 bp- ACCUCAGUG PROTEIN Met-Gln-Val----------------? Examples: Hemophilia A Gene mutations- types Normal state DNA ATGCAGGTGACCTCAGTG TACGTCCACTGGAGTCAC RNA AUGCAGGUGACCUCAGUG PROTEIN Met-Gln-Val-Thr-Ser-Val Mutation: type „deletion" DNA ATGCAGGTG TACGTCCAC RNA AUGCAGGUG PROTEIN Met-Gln-Val Examples: ° . ° o ° o o o ° Chloride ions o 0 small-cystic fibrosis large: Duchennes muscular dystrophy Four basic types of heredity dominant recessive Autosomal autosomal dominant (AD) autosomal recessive (AR) X-linked X-dominant (XD) X-recessive (XR) Monogenic disorders Determined by one locus alleli. Variant allele which had arosen sometimes in the history replaces original („wild") allele on one (heterozygote) or both (homozygote) chromosomes. Monogenic disorders have a characteristic transfer of the genotypes in families. Rare alleles are associated with monogenic disorders as a „big" factor. Pedigree Ö -0 6 6 m 0 o Key I ] male affected male 0 "eceased male affected female^f deceased fernale Monogenic disorders • Clinical manifestations are observed usually in childhood. • Less than 10% are manifested after puberty and only 1% after reproductive age. • Prevalence about 0.36%; in 6-8% hospitalizod children some monogenic disorder is suspected. Mitochondrial heredity • mtDNA is transferee! by mother (after fertilization, only maternal mitochondria are conserved). • Active process in paternal mitochondria elimination is supposed. 1 —J-1 12 3 4 5 •sub m rF 1 2 3 4 5 6 7 -rO 4-r-a ^tO T 8 9 10 8 9 10 11 12 13 14 15 Complex (multifactorial, multigene) diseases • Every disease has its own genetic predisposition with different impact to clinical manifestation and/or other phenotypes of the disease. Complex (multifactorial, multigene) diseases • They may be interactions of certain gene variants and certain environmental factors (and their combinations) which could be responsible for predisposition for many • biological processes • evolutional adaptations and/or • complex diseases. Monogenic disorder Mutation B—i-<» Inheritance pattern (dominant or recessive) ft. e c o ° ~ 9 100- ^ 2. c c 2 o » g = « p ° E * Ä o to w 5 » Genetic risk In population 5 10Ü LLILLLJJ 12 3 4 Genetic risk In different families Complex disorder Gene A Gene variations 5 -o -o S i * Inheritance pattern (complex) E nvironment/lif e-sly le * ~ ^ .5 c oc 30-1 l_ fb c 0 Ü o * A 111 Genetic risk in population (epidemiological evidence) I) a. B ABC A C A B A US Lil Family LEVEL IV ENDPOINT III RISK FACTOR II GENE PRODUCT I GENE environmental factors -> POLYGENE LDL-RECEPTOR LIKE MUTATIONS MAJOR QENE Fig. 1. A general model depicting the role of polygenes, major genes and environmental factors in the aetiology of a chronic multifactorial disease (adapted from Ref. [7] with permission from the authors and Oxford University Press, Oxford). The figure illustrates how genetic variation at level I (in polygenes, indicated by genes A, B... Z and in major genes indicated by LDLR mutations at the right) through altered gene products (level 11, indicated by shifts in the distribution) and interactions between them and environmental factors contribute to variations in biological risk factors (level 111) and ultimately to disease outcome (level IV). Note that the contribution of polygenic variation to biological risk factor variability is far more than that of major genes. Candidate gene and its association with disease ^The question is simplier in mendelistic diseases in which a change function of a gene can be easier indentified. • Two main possibilities for this strategy: • Linkage analysis ^needs examination of genealogy ^is evaluating common occurrence of genetic marker and disease in related individuals • Association study Genetic studies • Candidate gene selection strategy. ^Etiopatogenetic (pathophysiological) approach using for candidate gene se ection • Genome- wide analysis ^Based on analysis of large sequences of genome Association studies are evaluating common occurrence of genetic marker and disease in unrelated individuals Types of association studies \3 case-control (healthy-ill) Ucase-case (severity of disease, early onset of disease, risk factors for disease including gender Ugenotype-phenotype (e.g.biochemical parameters) Epigenetic effects Identical Twins with Different Hair Color Future: genome wide analysis and cadidate gene approach • Current genetic investigations are performed both on the basis of a rational and biologically based choice of candidate genes and through genome wide scans. • Nonetheless, lack of replication is a common problem in different genetic fields. Periodontal disease Health* Slate Disease Slate Periodontal Disease Plaque 41 A* Periodontitis " ^—^ '■ • Advanced gum inflanmiation • Bone loss *Inflamed Gmns • Destruction of ligaments Multifactorial disorder Endogenous Predispositions PwiodontoMthoginic Bacteria J Exoftneut 1 Rbk Factofi Peridontitis J! PNlstant ndiv-dujl 0 smoking poor oral q hygiene systemic diseases stress i n e i| .i Syndromic Forms of Periodontitis • Severe periodontitis presents as part of the clinical manisfestations of several monogenetic syndromes. • Significance of these conditions is that they clearly demonstrate that a genetic mutation at a single locus can impart susceptibility to periodontitis. TABLE 2 Examples of Syndromic Forms of Periodontitis in Which Inheritance is Mendelian and Due to a Genetic Alteration at a Single Gene Locus Condition Biochemical/Tissue Defect Inheritance OMIM AR 245000 AR 245100 AD 130050 AD 130080 AD 162800 AD 162700 AR 214500 AR 266265 AR 116920 Papillon-Lefevre syndrome Haim-Munk syndrome Ehlers-Danlos syndrome type 4 Ehlers-Danlos syndrome 8 Cyclic neutropenia Chronic familial neutropenia Chediak-Higashi syndrome Congenital disorder of glycosylation type lie Leukocyte adhesion deficiency type 1 Cathepsin C Cathepsin C Collagen Collagen neutrophil elastase Defect unknown lysosomal trafficking regulator gene GDP-fucose transporter-1 Leukocyte chain adhesion molecule CD18 Papillon LeFevre Syndrome Clinically characterized by: • Palmoplanar hyperkeratosis • Severe early onset periodontitis that results in premature loss of the primary and secondary dentition (distinguishes PLS from other plamoplantar keratoderma) Prevalence l/4million No gender or racial predilection CTSC gene encodes for Cathepsin C protease * CTSC gene lies on chromosone Ilql4-q21; seven exons encoding for lysosomal protease cathepsin C. It is expressed at high levels in a variety of immune cells including polymorphonuclear leucocytes, macrophages, and in epithelial regions commonly affected by PLS, including the palms, soles, knees, and oral keratinized gingiva (RT-PCR) (Hart et al., 1999). * Cathepsin C is a protease enzyme that processes and activates a number of granule serine proteases critical to immune and inflammatory responses of myeloid and lymphoid white blood cells utations in CTSC gene * Mutations in Cathepsin C (CTSC) gene are implicated for PLS • For example: • One exon 1 nonsense mutation (856C-^T): introduces a premature stop codon at amino acid 286. • Three exon 2 mutations: * single nucleotide deletion (2692delA) of codon 349: introduces a frameshift and premature termination codon, * 2 bp deletion (2673-2674delCT): introduces a stop codon at amino acid 343, and * G-^A substitution in codon 429 (2931G-^A): introduces a premature termination codon. • Truncated or altered conformation of the protein may not be transported to the organelle and may not be able to activate protein kinases * In other words, Cathepsin C activity in these patients is nearly absent Polymorphism Studies on Periodontitis • Host response is predominantly influenced by genetic make-up. • Several features of host's innate immune response may contribute to susceptibility to AgP and include epithelial, connective tissue, fibroblast, and PMN defects. • Aspects of the host inflammatory response namely cytokines are crucial variants influencing host respone in periodontitis. Immunological Polymorphisms • MHC or HLA genes determine our response to particular antigens. • Japanese study of AgP pts found a significant association for pts with atypical BamHl restriction site in the HLA.DQB gene (Takashiba et al. 1994). • Hodge & Kinane (1999) found no assoc. in Caucasian AgP pts and this restriction site. L-l Gene Polymorphisms • In 1997 Kornman et al found an association between polymorphisms in genes enconding for IL-la(-889) and IL-lB(+3953) and an increased severity of periodontitis. • The specific genotype of the polymorphic I L-l cluster (called PST-periodontitis susceptibility trait) was associated with severity of PD in only non-smokers, and distinguished individuals with severe periodontitis from those with mild disease. Genetic control of IL-1: Genes and Locus of SNPs associated with controlling IL-1 biological activity Fdlpuor pi fem Ci.ijr.r's.ai Locus Controlled oroduct IL-1A Allele 2 -889 Allele 2 IL-1 A +4845 IL-1 alpha IL-1B Allele 2 +3953 Allele 2 IL-IB +3954 IL-1 beta IL-1RN Protein receptor antagonist (impedes IL-1 alpha and beta) Genetic Susceptibility Test for periodontitis: tests for the presence of at least one copy of allele 2 at the IL-1 A +4845 loci and at least one copy of allele 2 at the IL-1 B +3954 locus. * IL-1 A +4845 is being used because it is easier to identify than IL-1 A -889 and it is essentially concordant with it. ** IL-1B +3953 has been now renumbered as IL-1B +3954 because the current convention indicates that the numbering of the transcription should begin at + 1 instead of zero. nterleukin 1 • A proinflammatory multifunctional cytokine. • Enables ingress of inflammatory cells into sites of infection • Promotes bone resoroption • Stimulates eicosanoid (PGE2) release by monocytes and fibroblasts • Stimulates release of MMP's that degrades proteins of the ECM. • Forms IL-lct and IL-1B IL-1 as modulator for Periodontitis Fibroblast Osteoblast \ Collagenase Bone ™" Resorption Tjsgue f Breakdown Osteoclast Fig. 7. IL-1 produced by macrophages (M0) as the major mediator of tissue breakdown in periodontal disease Prevalence of genotype positive individuals in different ethnic groups • Frequency of many genetic alleles varies between ethnic groups, therefore, it is necessary to establish allele frequencies in populations before genetic test can be evaluated and used. • Caucasions: • 29% of northern european caucasions were genotype positive (Kornman et alv 1997) • African Americans: • 14.5% of non-diseased individuals and 8% of patients with localized form of aggressive periodontitis were genotype-positive. (Walker et alv 2000) • Chinese: • 2.3% of sample of 132 mod-severe periodontitis cases were genotype-positive (Armitage et alv 2000) • Hispanics: • 26% of hispanic individuals with peridontitis were genotype-positive (Lopez et alv 2005) Take home message: Dissimilarity in the prevalence of genotypes in different ethnic groups precludes extrapolating data from one group to another. Pahogernc synergy n tie aetiology ol penodorial diseases Bactena capable ot causing Vsaue damage drecly (eg apeoes X) may be dependent on tie presence ot otiercets (e.g. organs ma C and D| tor eeaentai nutrients or attachment sles so that they can grow and reatet the removal tcrces provided by re ^creased ibw ol QC F. Simiany. boti ol these groups ot bacteria may be reftarl tor tie* survrvaJ on other onanisms (e.g. A and C) to modulate the host defences Individual bactena may have more than one rote (eg orgamsm C| *i tieaetotogy ol disease. 67 Microbial factors Porphyromonas gingivalis Bacteroides forsythus, newly Tanarella forsythensis Actinobacillus Actinomycemcomitans BUT The bacteria themselves are not able to cause disease: • A wide range of host susceptibility Differences in prevalence and extent between the teeth Dental plaque biofilm infection Ecological point of view • Ecological community evolved for survival as a whole • Complex community of more than 400 bacterial species Dynamic equilibrium between bacteria and a host defense • Adopted survival strategies favoring growth in plaque • "Selection" of "pathogenic" bacteria among microbial community • Selection pressure coupled to environmental changes • Disturbed equilibrium leading to pathology • Opportunistic infectio Reaction of the organism to bacteria infection • Gate input - usually mucosal surfaces (violation of integrity) • The fate of the host depends on: - Immunity (largely genetically determined) - Pathogenicity of bacteria (invasive ability, production of toxins, the ability to resist the defense mechanisms of the host) non-invasive - multiply the point of entry into the body threatening in case of toxin production (defense - only neutralizing Pt) Invasive - penetrate into the organism (x extracellular intracellular) (defense are Pt, complement, phagocytosis vs. macrophages) - The size of the infectious dose Identifying virulence factors • Microbiological and biochemical studies • In vitro isolation and characterization • In vivo systems • Genetic studies • Study of genes involved in virulence • Genetic transmission system • Recombinant DNA technology • Isogenic mutants • Molecular form of Koch's postulates (Falkow) 71 Koch's postulates • A Molecular form of Koch's postulates • The phenotype should be associated with pathogenic species (strains) • Specific inactivation of genes associated with virulence should lead to a decrease in virulence • Complementing inactivated genes with the wildtype genes should restore full virulence Falkow, 1988 72 Tooth plaque fatty acids f-MLP LPS enamel '^^^tma Bacterial tissue invasion cementům *£MT 3N. IL-8 IL-1ß IL-6 TN Fa PGE2 Allagen breakdown Bone Resorptk) antibody vessel m proteins protein complement fibrinogen TLRs • First described as a gene for type I transmembrane receptor —» important role in dorzoventral embryonic development of Drosophila -» absence of tolls has led to a serious brake-down of defense against fungi and bacteria G+ =^>Mammalian homologues - similar role?? TLRs receptors and ligands in periodontal disease PRR PAMP ILR-2 Lipoproteins Atypical LPS Outer membrane proteins Fimbriae Nonendotoxic glycoprotein TLR-4 HSP-60 (GroEL) LPS TLR-9 CpG-containing DNA Periodontal Pathogen Bacteroides forsythus* P. gingiva lis, C ochracea Oral treponemes P. gingivalis P. intermedia P. gingivalis A. octinnmyretemcomitans, F. nucleatum A. actinomycetemcomitans, P. gingivalis, P. micros LPS Monocyte Precursor cell • 'J I f BONE RESORPTION Local problem? Parodont - systémové efekty ■35 Bakterie Bakteriální produkt} (LPS) Zánětlivé mediatory (IL-l, INF-gamma. 1L-6. IL_8) Cévní řeěistč Systémové zánětlivé proeesy Srdce a cévy Endotcliální dysfunkce Ukládáni lipidů Mijjracc monocytů Prolíícrace hladké svaloviny Proteiny akutní fáze (CRP. SAA. 1L-6, TNF. IL-I) Placenta/uterus Kontrakce hladkých svalů dělohy Ruptuiy membrán Játra, pankreas inzulínová rezistence Ateroskleróza Kardiovask. nemoci ■ r Diabetes Nízká porodní hmotnost Periodontitis • follows the loss of pulp vitality - the dead tooth • Infection is usually odontogenic • Trauma - one-time or repetitive microtrauma • Acute periodontitis (apical) • Hyperemia and serous exudation • Suppuration, osteoclastic bone remodeling • Strong pain at all stages, swelling in the later stages • Relationship of polymorphisms in genes IL1B, IL1RN, FcyRlllb, VDR and TLR4 with an aggressive type of periodontitis. 79 Periodontitis Chronic periodontitis (periapical) Secondarily from acute periodontitis Primarily chronic (more frequent) • Forms: Granulomatous Granulomatous progressive - fistula (mucosal and cutaneous) Diffusion - dismantled and alveolar bone granulation tissue macrophages Possibility of creating radicular cysts The type of chronic periodontitis is associated with polymorphisms in genes for IL1B, IL1RN, IL6, IL10, VDR, CD14, TLR4 and MMP1. Meta-analysis of published data have associated variants ofpolymorphisms IL1A-889, IL1B 3954, IL1B-511, TNFA-308 and IL6-174 to aggressive and chronic periodontitis. 80 Thank you for your attention