BACKGROUND/AIM: Regressing nevi are considered an example of an efficient early antitumoral response preventing the development of neoplasia. The underlying mechanism has not been elucidated, although an immune-based destruction of melanocytes is supposed. The aim of this study was to provide evidence of an effective immunosurveillance of pigment lesions in a patient at high risk of melanoma. CASE REPORT: A patient with the dysplastic nevus syndrome and a history of melanoma was included in this study. Since 2003, a marked regression of almost all nevi was observed. Immunohistochemistry was performed and the antigen specificity of T-cells was analyzed on T-cells isolated from a regressing nevus by flow cytometry using HLA-A2-peptide tetramers containing Mart-1(26-35), gp100(280-288), gp100(209-217) and tyrosinase(369-377). Immunohistochemistry of the regressing nevi showed a strong infiltrate of CD4 + and CD8 + T-cells. Flow cytometric analyses demonstrated the presence of a CD8 + T-cell response against gp100(280-288) and Mart-1(26-35) both in peripheral blood and in a regressing nevus. CONCLUSION: These findings indicate that an immune reaction against melanocyte differentiation antigens can target specifically nevi without signs of vitiligo and suggests that boosting the anti-melanocyte immune response in patients at high risk for melanoma may prevent tumor development at an early stage.
BACKGROUND/AIM: Regressing nevi are considered an example of an efficient early antitumoral response preventing the development of neoplasia. The underlying mechanism has not been elucidated, although an immune-based destruction of melanocytes is supposed. The aim of this study was to provide evidence of an effective immunosurveillance of pigment lesions in a patient at high risk of melanoma. CASE REPORT: A patient with the dysplastic nevus syndrome and a history of melanoma was included in this study. Since 2003, a marked regression of almost all nevi was observed. Immunohistochemistry was performed and the antigen specificity of T-cells was analyzed on T-cells isolated from a regressing nevus by flow cytometry using HLA-A2-peptide tetramers containing Mart-1(26-35), gp100(280-288), gp100(209-217) and tyrosinase(369-377). Immunohistochemistry of the regressing nevi showed a strong infiltrate of CD4 + and CD8 + T-cells. Flow cytometric analyses demonstrated the presence of a CD8 + T-cell response against gp100(280-288) and Mart-1(26-35) both in peripheral blood and in a regressing nevus. CONCLUSION: These findings indicate that an immune reaction against melanocyte differentiation antigens can target specifically nevi without signs of vitiligo and suggests that boosting the anti-melanocyte immune response in patients at high risk for melanoma may prevent tumor development at an early stage.
Authors: Enrique Podaza; Ibel Carri; Mariana Aris; Erika von Euw; Alicia Inés Bravo; Paula Blanco; Juan Manuel Ortiz Wilczyñski; Daniel Koile; Patricio Yankilevich; Morten Nielsen; José Mordoh; María Marcela Barrio Journal: Front Immunol Date: 2020-06-05 Impact factor: 7.561