Global Cytokine Profiles and Association With Clinical Characteristics in Patients With Irritable Bowel Syndrome.
Evidence suggests that patients with irritable bowel syndrome (IBS) have an altered cytokine profile, although it is unclear whether cytokines are linked with symptom severity. We aimed to determine whether global serum and mucosal cytokine profiles differ between IBS patients and healthy subjects and whether cytokines are associated with IBS symptoms.



Serum from 144 IBS patients and 42 healthy subjects was analyzed for cytokine levels of interleukin (IL)-5, IL-6, IL-8, IL-10, IL-12p70, IL-13, IL-17A, interferon (IFN)-γ, and tumor necrosis factor (TNF) by MSD MULTI-ARRAY. In total, 109 IBS and 36 healthy sigmoid colon biopsies were analyzed for mRNA expression of IL-8, IL-10, TNF, and FOXP3 by quantitative reverse transcription PCR. Multivariate discrimination analysis evaluated global cytokine profiles. Rectal sensitivity, oroanal transit time, and psychological and gastrointestinal symptom severity were also assessed.



Global cytokine profiles of IBS patients and healthy subjects overlapped, but cytokine levels varied more in IBS patients. Serum levels of IL-6 and IL-8 tended to be increased and levels of IFN-γ tended to be decreased in IBS patients. Mucosal mRNA expression of IL-10 and FOXP3 tended to be decreased in IBS patients. Within both the full study cohort and IBS patients alone, serum level of TNF was associated with looser stool pattern, while subjects with more widespread somatic symptoms had increased serum levels of IL-6. Although neither IBS bowel habit subgroups nor patients with possible post-infectious IBS were associated with distinct cytokine profiles, a small cluster of IBS patients with comparatively elevated immune markers was identified.



Global cytokine profiles did not discriminate IBS patients from healthy subjects, but cytokine profiles were more varied among IBS patients than among healthy subjects, and a small subgroup of patients with enhanced immune activity was identified. Also, association of inflammatory cytokines with some clinical symptoms suggests that immune activation may be of importance in a subset of IBS patients.
Department of Internal Medicine and Clinical Nutrition, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.|Department of Microbiology and Immunology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
Sean M P
SM
Bennet
Department of Internal Medicine and Clinical Nutrition, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
Annikka
A
Polster
Department of Internal Medicine and Clinical Nutrition, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
Hans
H
Törnblom
Department of Internal Medicine and Clinical Nutrition, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.|Department of Microbiology and Immunology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
Stefan
S
Isaksson
Department of Life Science, Danone Nutricia Research, Palaiseau, France.
Sandrine
S
Capronnier
Department of Life Science, Danone Nutricia Research, Palaiseau, France.
Aurore
A
Tessier
Department of Life Science, Danone Nutricia Research, Palaiseau, France.
Boris
B
Le Nevé
Department of Internal Medicine and Clinical Nutrition, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.|Center for Functional GI and Motility Disorders, University of North Carolina, Chapel Hill, North Carolina, USA.
Magnus
M
Simrén
Department of Internal Medicine and Clinical Nutrition, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.|Department of Microbiology and Immunology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.|School of Health and Education, University of Skövde, Skövde, Sweden.
Lena
L
Öhman
D000328:Adult; D016022:Case-Control Studies; D012809:Colon, Sigmoid / Q000276:immunology* / Q000378:metabolism; D016207:Cytokines / Q000276:immunology*; D016002:Discriminant Analysis; D005260:Female; D051858:Forkhead Transcription Factors / Q000235:genetics / Q000276:immunology; D005772:Gastrointestinal Transit; D006801:Humans; D007371:Interferon-gamma / Q000276:immunology; D016753:Interleukin-10 / Q000235:genetics / Q000276:immunology; D018664:Interleukin-12 / Q000276:immunology; D018793:Interleukin-13 / Q000276:immunology; D020381:Interleukin-17 / Q000276:immunology; D015848:Interleukin-5 / Q000276:immunology; D016209:Interleukin-8 / Q000235:genetics / Q000276:immunology; D043183:Irritable Bowel Syndrome / Q000235:genetics / Q000276:immunology* / Q000503:physiopathology / Q000523:psychology; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012333:RNA, Messenger / Q000378:metabolism*; D012007:Rectum / Q000503:physiopathology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012720:Severity of Illness Index; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000276:immunology; D055815:Young Adult
C508606:CXCL8 protein, human; D016207:Cytokines; C418974:FOXP3 protein, human; D051858:Forkhead Transcription Factors; C508609:IL10 protein, human; C508717:IL17A protein, human; C508599:IL5 protein, human; D018793:Interleukin-13; D020381:Interleukin-17; D015848:Interleukin-5; D016209:Interleukin-8; D012333:RNA, Messenger; C439524:TNF protein, human; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10; D018664:Interleukin-12; D007371:Interferon-gamma