Zápalové črevné choroby Inflammatory bowel disease Roman Gardlík Ústav molekulárnej biomedicíny LF UK IBD
• Multifactorial disease – inappropriate immune response to gut microbes in a genetically predisposed host • CD • UC • Prevalence 10-500 per 100 000
• Clostridium difficile
• Irritable bowel syndrome • Mike McCready • Dwight Eisenhower • John F. Kennedy • Anastacia • Shannen Doherty Signs and Symptoms
• Intestinal • Extraintestinal • abdominal pain and cramps • anemia • diarrhea • fever • skin rash • rectal bleeding • arthritis • weight loss • tiredness • sensation of incomplete evacution • loss of appetite • constipation • night sweats • tenesmus • loss of normal menstrual cycle • growth delay in children • erythema nodosum • primary sclerosing cholangitis Crohn’s disease
• Dr. Burrill B. Crohn 1932 • Ileum and colon, but may affect any part of GIT • Affects the entire thickness of the bowel wall • Skip lesions • Abdominal pain, diarrhea, fever, weight loss • Not an autoimmune disease! • Males and females equally affected, smokers more likely • More common in developed world • Age 15-30, but can occur at any age Crohn’s disease Ulcerative colitis
• Colon only • Wilks and Moxon 1875 • Affects only epithelial lining – mucosa • Psychosomatic disease in 30s • Continuous lesions • Frequent stool, diarrhea with blood, anemia • Gradual onset • Intermittent course • More common in developed world • Proctitis, proctosigmoiditis, left-sided colitis, pancolitis • Lower risk for smokers • Likely an autoimmune disease Ulcerative colitis Ulcerative colitis
• Extraintestinal feratures in 6-47 % of patients • Aphthous ulcers of the mouth • Iritis or uveitis • Seronegative arthritis • Ancylosing spondylitis • Erythema nodosum • Pyoderma gangrenosum • Deep venous thrombosis and pulmonary embolism • Autoimmune hemolytic anemia CD vs. UC
Signs and symptoms Crohn's disease Ulcerative colitis Often porridge-like, Often mucus-like Defecation sometimes steatorrhea and with blood Tenesmus Less common More common Fever Common Indicates severe disease Fistulae Common Seldom Weight loss Often More seldom
Etiology
• Multifactorial disorder • Genetics • Immunology • Interaction with microbiome • Environmental factors
• Host-microbe interactions! • Intestinal permeability – epithelial dysfunction • Goblet cells – mucus production, epithelial repair • Paneth cells – antimicrobial peptides Erosions, ulcerations, low AMPs lead to exposure to intestinal microbiota Pathogenesis – epithelial dysfunction
• Defects in epithelial cell development and proliferation • Barrier function • Cell-matrix adhesion • Endoplasmic reticulum stress • Epithelial restitution after injury Pathogenesis – leukocyte infiltration
• Infiltration into lamina propria mucosae • Innate immune cells – neutrophils, macrophages, dendritic cells, NK-cells) • Adaptive immune cells (B cells and T cells) • Accumulation of leukocytes in intestinal tissue Increased levels of TNFα, IL1β, IFNγ, cytokines of IL23-Th17 pathway
Immune response to intestinal microbiota IBD genome
• Genome-wide association studies (GWAS) • Interaction between the host mucosal immune system and microbes is essential (at epithelial cell surface and within gut lumen) • 163 loci identified – most contribute to both CD and UC, some are specific IBD genome
• Possible causal genes play role in: • Defective processing of intracellular bacteria (NOD2, ATG16L1, IRGM genes) • Epithelial barrier function (HNF4A, CHD1, LAMB1 genes) • Antigen presentation (HLA-DQA1 gene) • Inflammatory mediator production (TNFRSF14, TNFSF9, IL1R2, IL7R genes) What triggers commensal microbiota to switch from symbiotic to pathogenic relationship with the host? Intestinal microbiota
• Development of intestinal immune system • Supplies nutrients • Modulates energy metabolism Intestinal microbiota in IBD
• IBD: genetic, immunological, environmental factors • Dysbiosis • Decrease in diversity • Crohn’s disease: high Bacteroidetes, low Firmicutes • High E. coli, low Faecalibacterium prausnitzii • Overproduction of proinflammatory cytokines • Ulcerative colitis: low Bacteroidetes, low Firmicutes • High Enterococcus and Gammaproteobacteria, low Bacteroides and Clostridium • Depending on disease activity and site of sampling! Intestinal microbiota in IBD
Kamada et al 2013 UC Current diagnosis
• Endoscopy • Biopsy • Clinical symptoms CD • Medical and family history • Lab tests – blood • Sedimentation, CRP, fecal calprotectin, complete blood count (anemia, thrombocytosis), electrolytes (hypokalemia, hypomegnesia), liver enzymes • Cultivation – stool (rule out infectious cause) • CT CD vs. UC
Diagnostic findings
Crohn's disease Ulcerative colitis
Terminal ileum involvement Commonly Seldom
Colon involvement Usually Always
Rectum involvement Seldom Usually
Involvement around Common Seldom the anus
No increase in rate of primary sclerosing Bile duct involvement Higher rate cholangitis
Distribution of Disease Patchy areas of inflammation (Skip lesions) Continuous area of inflammation
Deep geographic and serpiginous (snake- Endoscopy Continuous ulcer like) ulcers
Depth of inflammation May be transmural, deep into tissues Shallow, mucosal
Stenosis Common Seldom
May have non-necrotizing non-peri- Non-peri-intestinal crypt granulomas not Granulomas on biopsy intestinal crypt granulomas seen UC – Mayo Score CD – Crohn's Disease Activity Index
Clinical or laboratory variable Weighting factor
Number of liquid or soft stools each day for seven days x 2
Abdominal pain (graded from 0-3 on severity) each day x 5 for seven days
General well being, subjectively assessed from 0 (well) to x 7 4 (terrible) each day for seven days Presence of complications* x 20 Taking Lomotil or opiates for diarrhea x 30 Presence of an abdominal mass (0 as none, 2 as x 10 questionable, 5 as definite) Hematocrit of <0.47 in men and <0.42 in women x 6 Percentage deviation from standard weight x 1 Diagnosis – future outlook
• Evolution from „CD vs. UC“ • To: many subtypes of IBD • Serological markers • Genetic variants • Markers of inflammation • Microbial profile
• Genetic analysis (SNP) - Prediction of complications, therapeutic response, progression of the disease • Gene expression – reflecting immediate clinical situation Complications
• Bowel perforation • Pouchitis • Stricture • Fistulae • Nutrient deficiency • Uveitis/iritis • Endothelial dysfunction • Colorectal cancer Colon cancer
• Sporadic vs. colitis-associated • 1,5 to 2 times greater risk compared to general population • Patients with extensive colitis, active inflammation at higher risk • Chronic inflammation – oxidative stress induced DNA damage – activation of procarcinogenic genes / silencing of tumor suppressors • Altered microbiota promotes chronic inflammation and cancer • Such dysbiosis is reversible and transmissible to another individual • Importance of preventive and therapeutic manipulation with intestinal microbiota Longo, NEJM 2015 Microbe-host interactions in cancer
• Interactions between resident microbiota and the host are crucial for successful treatment of several diseases, including cancer which is not located in GIT • Gut microbiota affects inflammation and immunity locally at the mucosal level and systemically Therapy
• No causal treatment • Surgical / pharmacological
• Maintain clinical remission and prevent relapse • Induction therapy – maintenance therapy • Standard protocols Surgical therapy
• 70% of all patients • To address: abscess, bowel obstruction, cancer • Bowel resection • Colostomy, ileostomy Management Crohn's disease Ulcerative colitis Pharmacotherapy Mesalazine Less useful[25] More useful[25] Effective in long- Generally not Antibiotics term[26] useful[27] • Step-up vs. top-down strategy Often returns Usually cured by following Surgery removal removal of affected of colon • Glucocorticoids part • Immunomodulators (thiopurines – azathioprine, 6-mercaptopurine; methotrexate (CD)) • Aminosalicylates (UC) • Antibiotics • Biological therapy – TNF antibodies Biological therapy
• TNFα • Infliximab • Adalimumab • Golimumab • Certolizumab pegol • IL-12 and IL-23 • Ustekinumab • α4β1 and α4β7 • Natalizumab • α4β7 • Vedolizumab
Nielsen 2014, Frontiers in Medicine Biological therapy – drawbacks
• Allergic reactions • Loss of efficiency – rapid clearance • Antibodies against therapeutics • Reactivation of old infections • JC virus induced multifocal leukoencephalopathy – natalizumab • Tuberculosis – infliximab • Price Novel therapeutic approaches - CD
• Phase II and/or III • Anti-cytokines • Anti-IL-12/-23 mAb • JAK inhibitor • Anti-IL-23 mAb • Anti-IL-6 mAb • Anti-IL-13 mAb • TLR-9 agonist • Selective anti-migration agents • Anti-α4β7 mAb • CCR9 antagonist • Anti-CXCL-10 mAb • Anti-MadCAM mAb • Anti-NKG2D mAb • Anti-β7 mAb • Human stem cells / bone marrow transplant Treg cells Novel therapeutic approaches - UC
• Phase II and/or III • Anti-cytokines • JAK inhibitor • TLR-9 agonist • Selective anti-migration agents • Anti-α4β7 mAb • CCR9 antagonist • Anti-CXCL-10 mAb • Anti-MadCAM mAb • Anti-β7 mAb • Anti-eotaxin-1 mAb Novel therapeutic approaches
• Anti-TNF vaccination (phase II) • TNF gene silencing with siRNA • TNF-neutralising nanobodies • Individualized biological therapy
• Probiotics – Lactobacillus sp, Bifidobacterium sp, Sacchromyces bouladrii, E. coli Nissle 1917, VSL#3 (Lactobacilli, Bifidobacteriae, Streptococcus) • Helminths – Trichuris suis • Stem cells Helminths
• Polarisation of T-cell responses
Wammes et al. Lancet Infect Dis 2014 Hua et al 2015, Nanomedicine Targeted therapy
• pH specific coatings • Enzymatic activity of colonic bacteria • Time-specific release - GIT transit time • Intestinal microbiota • Nano-delivery systems (100-300 nm particles) Gene therapy
• Alicaforsen – antisense oligonucleotide ICAM-1 • Mongersen – antisense oligonucleotide SMAD7 (TGFβ1 inhibitor) Stem cell therapy
• Requirements for cells to be efficient: • High migration capacity • Homing into intestine • High survival after transplantation • Regulation of immune system • Invisible to patients immune system Stem cells
• Correction of genetic predisposition • Provide healthy cells • Gut trophic factors – tissue repair (proliferation and differentiation), remodeling, regulation of immune response • Clinical studies - Mesenchymal / Hematopoietic stem cells (i.p. / i.v.) • Intestinal stem cells
• iPSC – (Oct-4, Sox2, Kfl4, c-Myc) • In vivo induced pluripotency Therapeutic manipulation of the microbiome
• Dysbiosis – IBD patients vs. healthy subjects
• Antibiotics • Probiotics • Prebiotics • Diet • Fecal microbiota transplantation FMT - fecal microbiota transplantation
• 1958 pseudomembranous colitis • 1983 C. difficile infection • First time in IBD – 1989 Justin Bennet with severe UC self-administered a fecal infusion and stayed symptom-free for 6-months
Gastroenterology, 2015 FMT - fecal microbiota transplantation Animal models
• Chemical – dextran sulfate sodium, trinitrobenzene sulfonate, oxazolone • Immunological – T-cell transfer to immunodeficient mice • Genetic – IL10 knock-out • https://www.youtube.com/watch?v=Keqzt83KMVA