Increased FOXP3 expression in small-bowel mucosa of children with coeliac disease and type I diabetes mellitus.
OBJECTIVE
To determine whether the expression of FOXP3 is changed in small-bowel mucosa in coeliac disease (CD).


METHODS
The study comprised 52 patients (mean age 8.01+/-6.14 years) who had undergone small-bowel biopsies. CD only was diagnosed in 16 patients, and CD with type I diabetes mellitus (T1D) in 7. These 23 patients and 4 others without CD had partial or subtotal villous atrophy (PVA, SVA). Twenty-five persons without CD had normal mucosa. The transcription level of the FOXP3 gene (Hs00203958_m1) was evaluated in biopsy samples (small bowel) using TaqMan gene expression assays. FOXP3 protein in mucosal cells was evaluated with mouse anti-human FOXP3 antibodies and CD25(+), and CD4(+) T cells were evaluated by mouse monoclonal antibodies.


RESULTS
Expression of FOXP3 mRNA was higher in both PVA and SVA compared to normal mucosa (p=0.007). Patients with CD and T1D had higher expression of FOXP3 mRNA than patients with CD alone (p=0.02). The number of FOXP3(+) cells in intestinal mucosa was higher in patients with CD, especially those with coexisting T1D, than in those with normal mucosa (p=0.01). The results of double staining showed that, among all positive cells, FOXP3 expression alone was revealed in 25.6% of the cells, CD25 positivity in 18% and both markers simultaneously were found in 56.5% of lymphocytes (p=0.03). Double staining for CD4 and FOXP3 showed that 87.5% of cells were CD4(+), 2.8% were FOXP3(+) and 9.7% of cells simultaneously expressed the CD4 and FOXP3 markers.


CONCLUSIONS
A more pronounced expression of FOXP3 mRNA and also the number of FOXP3(+) cells (with simultaneous expression of CD25 and CD4 markers) were found in the small-bowel biopsy specimens obtained from children with CD, particularly those with coexisting T1D, compared with the FOXP3 expression in normal mucosa.
Vorobjova
Tamara
T
Department of Immunology, Institute of General and Molecular Pathology, University of Tartu, Tartu, Estonia. tamara.vorobjova@kliinikum.ee
Uibo
Oivi
O
Heilman
Kaire
K
Rägo
Tiina
T
Honkanen
Jarno
J
Vaarala
Outi
O
Tillmann
Vallo
V
Ojakivi
Ivi
I
Uibo
Raivo
R
D000293:Adolescent; D015704:CD4 Antigens / Q000378:metabolism; D016022:Case-Control Studies; D002446:Celiac Disease / Q000150:complications* / Q000235:genetics / Q000378:metabolism*; D002648:Child; D002675:Child, Preschool; D003922:Diabetes Mellitus, Type 1 / Q000150:complications / Q000235:genetics / Q000378:metabolism*; D005260:Female; D051858:Forkhead Transcription Factors / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007223:Infant; D053645:Interleukin-2 Receptor alpha Subunit / Q000378:metabolism; D007413:Intestinal Mucosa / Q000378:metabolism* / Q000473:pathology; D007421:Intestine, Small / Q000378:metabolism* / Q000473:pathology; D008297:Male; D012333:RNA, Messenger / Q000378:metabolism; D050378:T-Lymphocytes, Regulatory / Q000502:physiology; D055815:Young Adult
D015704:CD4 Antigens; C418974:FOXP3 protein, human; D051858:Forkhead Transcription Factors; D053645:Interleukin-2 Receptor alpha Subunit; D012333:RNA, Messenger