The Role of Cytokines in Vitiligo

Background: Vitiligo is an acquired disorder of melanin pigmentation that affects approximately 0.5-
2% of the population. It is characterized by macular depigmentation of varying sizes or shapes with a
tendency to progress. Depending on the extent of the lesions, vitiligo can be classified into two main
categories: generalized and localized. Although several theories have been proposed to explain the
loss of melanocytes in vitiligo the pathogenesis of the disease is still unclear. The clinical association
with autoimmune disorders and organ specific antibodies indirectly support the idea of an autoimmune
pathogenesis of the disease. Furthermore, many patients with vitiligo have serum auto antibodies
and circulating auto reactive T cells directed against melanocytes and there are findings of activated
T-cells in the periphery of actively progressing lesions in some vitiligo patients. Several studies have
shown that within the cascade of pathogenesis of vitiligo, cytokines play an important role. An
imbalance of several melanogenic cytokines that can affect melanocyte activity and survival has been
shown in vitiligo lesional skin and serum of vitiligo patients.
Objectives: Cytokines are the key mediators for cellular communication and networking. Although it
is well known that multiple cytokines simultaneous play role in vitiligo, the aim of our study was to
evaluate serum concentrations of interleukin- IL-2 (IL-2) and interleukin-2 soluble receptor (IL-2 sR) in
patients with vitiligo and healthy subjects and also to asses a possible association between these
cytokines and duration of the disease.
Study Design: Case control study.
Place of the Study: The study was carried out in University Clinical Center Sarajevo, Department of
Dermatology and Venereology.
Patients and Methods: Twenty one patients (11 female and 10 male; age range 15-53 years) with
vitiligo and 20 healthy controls (10 female and 10 male; age range 17-52) were enrolled in the study. c
The duration of vitiligo ranged from 2 to 252 months. Ten patients (47.62%) had generalized, and
eleven patients (52.38%) had localized vitiligo Serum concentrations of cytokines were measured
using enzyme-linked immunoassay techniques.
Results: Both IL-2 (median 22.600 pg/ml, range 20.900-76.100) and IL-2sR (median 76.100 pg/ml,
range 15.700-183.800) in the patient group were significantly higher when compared with that of the
normal controls. When the serum cytokine level in vitiligo group were compared to total disease
duration (Spearman correlation ρ), serum IL-2 was negatively (ρ= -0.000573, P= 0.9980) and IL-2 sR
was positively (ρ=0.241, P= 0.2797) correlated with total disease duration, but it is of borderline
significance.
Conclusions: Although the initiating event in vitiligo has not yet been defined, a growing body of
evidence indicates that cytokines may help the development and the perpetuation of the chronic
inflammatory state. The results presented in our study demonstrate that the median levels of IL-2 and
IL-2 sR were significantly elevated in vitiligo patients in comparison with healthy subjects. Vitiligo is
an acquired depigmentary skin inflammatory disorders. Although the initiating event in vitiligo has not
yet been defined, a growing body of evidence indicates that cytokines may help the development and
the perpetuation of the chronic inflammatory state. An increase in the production of pro-inflammatory
cytokines in vitiligo patients, may play an important role in melanocytic cytotoxicity. The imbalance
observed in the cytokines examined in the current study suggest their involvement in the
pathogenesis of vitiligo. This research could contribute to the interpretation of the role and significance
of cytokines in the pathogenesis of vitiligo, and these findings may provide important clues to assist in the development of new therapeutic strategies for patients with vitiligo. The specific blockade of
cytokines or their receptors is an alternative approach for the treatment of vitiligo.