Roger M. Arce

University of North Carolina at Chapel Hill 1

Periodontal Disease and Preterm Delivery:Influences of Campylobacterrectus Infection onPlacental Innate ImmunityRoger M. Arce DDS. MS.Oral Biology PhD CandidateCenter for Oral and Systemic DiseasesSchool of DentistryUniversity of North Carolina at Chapel Hill

• The WHO defines PTD as birth at less than 37 completed gestational weeks.

• Preterm delivery (PTD) is the

Introduction

• Preterm delivery (PTD) is the major cause of neonatal mortality and morbidity in the world.

• PTD rates have increased up to 12.7%, despite current public health policies andpublic health policies and advanced medical interventions.

Goldenberg RL, Culhane JF, Iams JD, Romero R. Epidemiology and causes of preterm birth.Lancet 2008 5;371(9606):75-84.

Roger M. Arce

University of North Carolina at Chapel Hill 2

• Maternal infections account for most of preterm delivery cases (25-40%) and uterine

Introduction

cases (25 40%), and uterine infections have been reported to be the leading cause of PTD.

• There is conflicting evidence coming from randomized clinical trials evaluating theclinical trials evaluating the real benefits of antibiotic therapy in pregnant women.

Romero R, Mazor M, Munoz H, Gomez R, Galasso M, Sherer DM. The preterm labor syndrome. Ann N

Y Acad Sci 30;734:414-29 U. urealyticum

Preterm delivery pathogenesis

Microbial stimuli Stress proteins

?

Physical or psychological stress

(hypothalamic-pituitary-adrenal axis), vasculopathy, hypoxia

Inflammation/infection

?

Cytokines and chemokines upregulation(IL-1β, TNF-α, IL-6, IL-8 and others)

Prostaglandins’

Gomez R, Romero R, Edwin SS, David C. Pathogenesis of preterm labor and preterm premature rupture of membranes associated with intraamniotic infection. Infect Dis Clin North Am 1997 11(1):135-76.

Myometriumcontractions

Cervixripening

Membranerupture

MMP’sNeutrophils and

Macrophages recruitmentDecidual hemorrhage

(Vaginal bleeding)Pathological uterine

distention(polyhydramnios)

Roger M. Arce

University of North Carolina at Chapel Hill 3

Background

Oral pathogens?

• Periodontal diseases (gingivitis and periodontitis) are part of the most common chronic infections affecting up to 50% of humans and have been found to be an independent putative risk factor for pregnancy-

pathogens?

putative risk factor for pregnancyrelated complications after adjusting for other known obstetric risk factors.

Offenbacher S, Boggess KA, Murtha AP, Jared HL, Lieff S, McKaig RG, Mauriello SM, Moss KL, Beck JD. Progressive periodontal disease and risk of very preterm delivery. Obstet Gynecol 2006 107(1):29-36.

V. parvulaA. odontolyticus*

Oral Microbial Complexes

P. gingivalisB. forsythusT. denticola

E. corrodensC. gingivalisC. sputigena

S. mitisS. oralisS. sanguis

S. gordoniiS. intermedius

P. intermediaP. nigrescensP. microsF. nucleatumF. periodonticum

E. nodatumS. constellatus

C. showae

C. rectusC. gracilis

S no ia

*

****

*

****

*

*

**

C. ochraceaA. actino. a

S. noxia

Socransky et al. 1998

**

Roger M. Arce

University of North Carolina at Chapel Hill 4

Oral periodontopathogens

Madianos PN, et al. Maternal periodontitis and prematurity.Part II: Maternal infection and fetal exposure. Ann Periodontol 2001 6(1):175-82.

Campylobacter spp.

surface layer (S la er)

RTX proteins

GroEL-like protein

500nm

(S-layer) proteins cytolethal distending toxin

(CDT)lipopolysaccharide

Campylobacter jejuni (acute gastroenteritis-

diarrhea) and Campylobacter fetus

(sheep and cattle

Thompson SA. Campylobacter surface-layers (S-layers) and immune evasion. Ann Periodontol 2002 December;7(1):43-53.

C. rectus is an orally-exclusive Gram negative anaerobe and motile bacterium that plays a pathogenic role in

human periodontitis.

flagella (sheep and cattle abortion)0.5µm

100nm

Roger M. Arce

University of North Carolina at Chapel Hill 5

Toll-like receptors (TLRs)

Microbial stimuli Stress proteins

Toll-like receptors

Cytokines and chemokines upregulation(IL-1β, TNF-α, IL-6, IL-8 and others)

ProstaglandinsMMP’s

Neutrophils and

•Patni S, Flynn P, Wynen LP, Seager AL, Morgan G, White JO, Thornton CA. An introduction to Toll-like receptors and their possible role in the initiation of labour. BJOG 2007 114(11):1326-34.

Myometriumcontractions

Cervixripening

Membranerupture

Neutrophils and macrophages recruitment

Big picture

?

Roger M. Arce

University of North Carolina at Chapel Hill 6

Animal models: subcutaneous chamber

NormalC. rectus

109 CFU, E(7.5)

Increased TLR-4 expression in trophoblasts afterC. rectus infection (E16.5 placentas)

Bobetsis YA, Barros SP, Lin DM, Weidman JR, Dolinoy DC, Jirtle RL, Boggess KA, Beck JD, Offenbacher S. Bacterial infection promotes DNA hypermethylation. J Dent Res 2007 86(2):169-74.

Control C. rectus infected

Roger M. Arce

University of North Carolina at Chapel Hill 7

Presence of inflammatory infiltrate in placentas from C. rectus-challenged mice

Animal models: oral infection

OralBacteriaTopical

application

R.M. Arce, S.P. Barros, B. Wacker, B. Peters, K. Moss and S Offenbacher. Increased TLR4 expression in murine placentas after oral infection with periodontal pathogens. Submitted to Placenta, September 2008.

Roger M. Arce

University of North Carolina at Chapel Hill 8

Toll-like receptors (TLRs) in pregnancyImplantation Maintenance

•Abrahams VM, Mor G. Toll-like receptors and their role in the trophoblast. Placenta 2005 26(7):540-7.•Koga K, Mor G. Expression and function of toll-like receptors at the maternal-fetal interface. Reprod Sci 2008 April;15(3):231-42

the fact that specific toll like receptors or associated pathways prevail during

placental inflammation may give new insights in understanding PTD

pathogenesis.

Detection of C. rectus in the placenta

control challenged

C. rectus was detected in 7 out of 11 challenged placentas stained.

challenged challenged

Roger M. Arce

University of North Carolina at Chapel Hill 9

Invasion of human trophoblast BeWo cells by C. rectus, C. rectus S-layer mutant and C. jejuni

no bacteria C. rectus

C. rectus S-layer mutant C. jejuni

• Periodontopathogenic oral infection with C. rectus significantly affected fecundity in a murine model of pregnancy.TLR 4 i d t b i ifi tl

Conclusions

• TLR-4 expression appeared to be significantly up-regulated after Campylobacter rectus infection in two different models of systemic infection (chamber and oral infection).

• Histological analysis revealed focal decidual inflammatory sites and labyrinth trophoblast TLR-4 y y pincreased expression in murine placentas.

Roger M. Arce

University of North Carolina at Chapel Hill 10

• To determine the systemic dissemination of C. rectus to placenta, liver and spleen by nested PCR in the murine model of oral infection.

Future directions

• To determine oral bacterial colonization, alveolar bone resorption and bacterial viability in the murine model of oral infection.

• To determine the level of systemic proinflammatory maternal markers of inflammation (i.e. cytokines).

• To evaluate the trophoblast inflammatory responses to periopathogens in vitro.

• To investigate the role of TLRs in mediating placental inflammatory responses in vivo.

roger_arce@dentistry.unc.edu

Gracias!