Modulation of cytokine patterns and microbiome during pregnancy in IBD

AbSTrACT
Objective Pregnancy may affect the disease course of
iBD. Both pregnancy and iBD are associated with altered
immunology and intestinal microbiology. however, to
what extent immunological and microbial profiles are
affected by pregnancy in patients with iBD remains
unclear.
Design Faecal and serum samples were collected
from 46 iBD patients (31 crohn’s disease (cD) and
15 Uc) and 179 healthy controls during first, second
and third trimester of pregnancy, and prepregnancy
and postpartum for patients with iBD. Peripheral
blood cytokine profiles were determined by elisa, and
microbiome analysis was performed by sequencing the
V4 region of the bacterial 16s rrna gene.
results Proinflammatory serum cytokine levels in
patients with iBD decrease significantly on conception.
reduced interleukin (il)-10 and il-5 levels but increased
il-8 and interferon (iFn)γ levels compared with healthy
controls were seen throughout pregnancy, but cytokine
patterns remained stable during gestation. Microbial
diversity in pregnant patients with iBD was reduced
compared with that in healthy women, and significant
differences existed between patients with Uc and
cD in early pregnancy. however, these microbial
differences were no longer present during middle and
late pregnancy. Dynamic modelling showed considerable
interaction between cytokine and microbial composition.
Conclusion serum proinflammatory cytokine levels
markedly improve on conception in pregnant patients
with iBD, and intestinal microbiome diversity of patients
with iBD normalises during middle and late pregnancy.
We thus conclude that pregnancy is safe and even
potentially beneficial for patients with iBD.