CD80, suPAR y síndrome nefrótico en un caso de mutación del gen NPHS2

Cara-Fuentes, Gabriel; Araya, Carlos; Wei, Changli; Rivard, Christopher; Ishimoto, Takuji; Reiser, Jochen; Johnson, Richard J.; Garin, Eduardo H.

doi:10.3265/Nefrologia.pre2013.Jun.12085

Article information

Antecedentes: Las mutaciones de la podocina están caracterizadas por la progresión hacia enfermedad renal terminal y por hallazgos histológicos de glomeruloesclerosis segmentaria y focal (GSF). CD80 es una proteína podocitaria que parece tener un papel en la proteinuria de la enfermedad de cambios mínimos, mientras que el receptor soluble de la uroquinasa (suPAR) es característicamente elevado en el suero de pacientes con GSF. Métodos: En un paciente con síndrome nefrótico y mutación de la podocina, se cuantificó CD80 y suPAR en suero y orina usando los kits disponibles en el mercado. El peso molecular del CD80 urinario fue determinado mediante Western blot. Se realizó la tinción para CD80 y podocina en el glomérulo. Resultados: El paciente presentó niveles urinarios marcadamente elevados de CD80 y ligeramente elevados de suPAR en comparación con controles. El nivel sérico de CD80 se encontró dentro del rango observado en controles. El nivel sérico de suPAR fue elevado, aunque en el límite inferior del rango publicado para pacientes con GSF primaria. La inmunofluorescencia de la biopsia renal mostró expresión glomerular de CD80. Conclusión: La combinación de biomarcadores séricos y urinarios quizás ayude a diferenciar entre diferentes formas de GSF. Niveles elevados de CD80 en orina y suPAR en suero quizás representen un perfil característico que permita diferenciar entre esta forma genética de GSF y GSF de causa primaria.

Palabras clave:

suPAR

Palabras clave:

Mutación de la podocina

Palabras clave:

Podocito

Palabras clave:

Síndrome nefrótico

Palabras clave:

CD80

Background: Podocin mutations are characterized by progression to end stage renal disease and histologic findings of Focal Segmental Glomerulosclerosis (FSGS). CD80 is a podocytes protein that may play a role in proteinuria, particularly in Minimal Change Disease whereas the soluble urokinase receptor (suPAR) is characteristically elevated in the serum of FSGS patients. Methods: In a patient with nephrotic syndrome and podocin mutation, urinary and serum CD80 as well as suPAR were measured using commercially available kits. Urinary CD80 molecular size was determined by western blot analysis. Glomerular staining for CD80 and podocin was performed. Results: Patient displayed marked elevated CD80 and mildly increased suPAR urinary levels compared to controls. Serum CD80 level was within the range observed in normal controls. Serum suPAR level was elevated, albeit in the lower range reported for patients with primary FSGS. Immunofluorescence examination of kidney biopsy revealed glomerular CD80 expression. Conclusion: The combination of serum and urinary biomarkers can help differentiate various forms of FSGS. High urinary CD80 and elevated serum and urinary suPAR might represent a profile to differentiate this genetic form of FSGS from primary FSGS.

Keywords:

suPAR

Keywords:

Podocin mutation

Keywords:

Podocyte

Keywords:

Nephrotic syndrome

Keywords:

CD80

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