Objective. The aims of this study
were: 1) to investigate forkhead box P3
(FOXP3) expression in patients with
Kawasaki disease (KD), exploring possible
differences during the acute phase
and after defervescence; 2) to evaluate
a possible association of the FOXP3
single nucleotide polymorphism (SNP)
543 (SNP ID: rs2232367) with KD.
Methods. FOXP3 expression was evaluated
on 8 children with KD and 15
healthy children by flow cytometry and
Real-Time polymerase chain reaction
(RT-PCR). FOXP3 SNP 543 was genotyped
by denaturing high-performance
liquid chromatography (DHPLC) and
sequencing on DNA samples from 58
additional children with KD and 114
healthy donors.
Results. The frequencies of CD4+CD25
+FOXP3+ regulatory T cells were significantly
(p=0.0002) lower during the
acute phase of KD than in sex-and agematched
healthy donors (median % +
SD: 4.8±1.3 vs. 7.7±1.7) and a similar
tendency was revealed for FOXP3
mRNA transcripts (p<0.0001). FOXP3
expression increased significantly, at
both protein and mRNA levels, after
intravenous immunoglobulin (IVIG)
therapy treatment and achieving complete
remission of disease (at least 48
hrs; median 9.5 days, range 2-30).
Of the 58 patients screened, only one
female subjects (1.7%) carried the
presence of 543 SNP in heterozygosis
(C>T; for a total of 1 allele out of 88),
with no difference between KD patients
and controls (0.0%, 0/203 alleles).
Conclusion. Our data reinforces the
notion of an impaired immunoregulation
in KD, suggesting also a role of
IVIG treatment in modifying the Treg
compartment. FOXP3 SNP 543 do not
seem to be involved in susceptibility to
KD in Italian children
