Melanoma Inhibitory Activity (MIA) Is Able to Induce Vitiligo-Like Depigmentation in an in vivo Mouse Model by Direct Injection in the Tail

From mice to men: An assessment of preclinical model systems for the study of vitiligo

Vitiligo is an autoimmune skin disease of multiple etiology, for which there is no complete cure. This chronic depigmentation is characterized by epidermal melanocyte loss, and causes disfigurement and significant psychosocial distress. Mouse models have been extensively employed to further our understanding of complex disease mechanisms in vitiligo, as well as to provide a preclinical platform for clinical interventional research on potential treatment strategies in humans. The current mouse models can be categorized into three groups: spontaneous mouse models, induced mouse models, and transgenic mice. Despite their limitations, these models allow us to understand the pathology processes of vitiligo at molecule, cell, tissue, organ, and system levels, and have been used to test prospective drugs. In this review, we comprehensively evaluate existing murine systems of vitiligo and elucidate their respective characteristics, aiming to offer a panorama for researchers to select the appropriate mouse models for their study.

Efficacy of a topical formulation containing MIA (Melanoma Inhibitory Activity) - Inhibitory peptides in a case of recalcitrant vitiligo in combination with UV exposure

INTRODUCTION

Vitiligo is an acquired chronic pigmentation disorder of the skin. Even if the role of the immune system seems to be well established, new pathogenetic hypothesis are rising in these years. It has been recently suggested by the development of an animal model that a protein called Melanoma Inhibitory Activity (MIA) is involved in the pathogenesis of vitiligo. This protein interacts with the adhesion molecules expressed on the melanocytes causing its detachment from extracellular matrix proteins and creating the depigmented macules. A topical preparation based on oligopeptides able to inhibit the actions of the MIA protein has been introduced to the market, claiming activity on vitiligo.

PATIENT CONCERNS AND DIAGNOSIS

A patient affected by non-segmental vitiligo for 10 years, recalcitrant to any treatment (such as steroids, immunomodulators, kellin, UVB-NB and UVA) came to our observation.

INTERVENTIONS

We used this topical preparation containing the MIA inhibitors peptides in selected areas (face and sides of the trunk) leaving untreated other areas as control (legs and arms). The patient was required to be sun exposed or to have some UVA sessions during the treatment to stimulate the melanocytes replications.

OUTCOMES

After 9 months of treatments, he recovered from 50% to 80% of repigmentation only in the treated areas, without any side effects locally or systemically.

CONCLUSION

Even if other studies are required to better determine the efficacy of this approach, this first observation about the use of the MIA-inhibitors peptides for the treatment of non-segmental vitiligo indicates that this topical preparation containing the MIA inhibitors peptides could be a very promising option for the cure of this disease.

Prognostic Value of Lactate Dehydrogenase, Melanoma Inhibitory Protein, and S-100B Protein in Patients with Malignant Melanoma

Objective

This investigation probed the prognostic potential for lactate dehydrogenase (LDH), melanoma inhibitory activity protein (MIA), and S-100B protein in cases of malignant melanoma.

Methods

84 cases were segregated into effective cohort (n = 64) and ineffective cohort (n = 20) depending on clinical efficacy. The cases were followed up for three years and segregated into mortality cohort (n = 29) and survival cohort (n = 55) depending upon 3-year survival. Serum LDH, MIA, and S-100B levels were compared across the effective and ineffective cohorts. Serum LDH, MIA, and S-100B levels in cases of different clinical stages were comparatively analyzed, with correlations of these indicators with the clinical stage being evaluated. ROC evaluated the prognostic potential of serum LDH, MIA, and S-100B. Cases were segregated into the high-level and low-level cohorts according to serum LDH, MIA, and S-100B levels, and the survival rates of cases were compared.

Results

The levels of LDH, MIA, and S-100B in the effective cohort were significantly lower than those in the ineffective cohort. The AUC value of the composite indicator of serum LDH, MIA, and S-100B for effectiveness evaluation was (0.839). Serum LDH, MIA, and S-100B levels were positively linked to the clinical stage. AUC value of the composite indicator of serum LDH, MIA, and S-100B for prognosis evaluation prediction (0.942) was elevated compared to LDH (0.632), MIA (0.732), or S-100B (0.828) alone. Survival rate of cases of LDH ≥30.56 mg/L (57.14%, 32/56) was lower than that of cases of LDH <30.56 mg/L (82.14%, 23/28) (log-rank χ 2  = 4.672, P < 0.05). The survival rate of MIA ≥5.34 ng/mL cases was lower than that of MIA <5.34 ng/mL cases. The survival rate of cases of S-100B ≥ 1.03ug/L was lower than that of S-100B < 1.03ug/L.

Conclusion

Serum LDH, MIA, and S-100B protein levels are linked to the clinical stage. The lactate dehydrogenase, melanoma inhibitory protein, and S-100B protein are of good clinical effectiveness and have the prognostic potential for cases of malignant melanoma.

Current Concepts of Vitiligo Immunopathogenesis

Vitiligo is an acquired immune-mediated disorder of pigmentation clinically characterized by well-defined depigmented or chalk-white macules and patches on the skin. The prevalence of vitiligo varies by geographical area, affecting 0.5% to 2% of the population. The disease imposes a significant psychological burden due to its major impact on patients’ social and emotional aspects of life. Given its autoimmune background, vitiligo is frequently associated with other autoimmune diseases or immune-mediated diseases. Vitiligo is a multifaceted disorder that involves both genetic predisposition and environmental triggers. In recent years, major predisposing genetic loci for the development of vitiligo have been discovered. The current findings emphasize the critical role of immune cells and their mediators in the immunopathogenesis of vitiligo. Oxidative-stress-mediated activation of innate immunity cells such as dendritic cells, natural killer, and ILC-1 cells is thought to be a key event in the early onset of vitiligo. Innate immunity cells serve as a bridge to adaptive immunity cells including T helper 1 cells, cytotoxic T cells and resident memory T cells. IFN-γ is the primary cytokine mediator that activates the JAK/STAT pathway, causing keratinocytes to produce the key chemokines CXCL9 and CXCL10. Complex interactions between immune and non-immune cells finally result in apoptosis of melanocytes. This paper summarizes current knowledge on the etiological and genetic factors that contribute to vitiligo, with a focus on immunopathogenesis and the key cellular and cytokine players in the disease’s inflammatory pathways.