ab1904

Immunogenetics and clinical aspects of Takayasu's arteritis patients in a Mexican Mestizo population

G. Vargas-Alarcón¹, C. Flores-Domínguez¹, G. Hernández-Pacheco¹, J. Zuñiga², R. Gamboa¹, M.E. Soto¹, J. Granados³, P.A. Reyes¹

¹Departments of Physiology and Immunology, Instituto Nacional de Cardiología Ignacio Chávez; ²Service of Infectology, Instituto Nacional de Enfermedades Respiratorias; ³Department of Immunology and Rheumatology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico.

ABSTRACT
Objective
The aim of the present work was to study the association between HLA alleles and Takayasu's arteritis in Mexican Mestizo patients.

Methods
The study included 26 Mexican Mestizo patients with Takayasu's arteritis and 99 healthy unrelated individuals. HLA-A, -B and -DR alleles were determined by polymerase chain reaction PCR-SSP.

Results
Increased gene frequencies were demonstrated for HLA-B15 (p=0.009, pC=0.020, OR=3.24, EF=11.9%) and HLA-B52 (p=0.008, pC=0.027, OR=5.16, EF=7.7%), and a decreased frequency for the HLA-A24 allele in patients compared to normal controls (p=0.035, pC=NS, PF=11.1%). When HLA typing was correlated to clinical features in 24 cases, we found an increased frequencies of HLA-DR14 in patients with systemic arterial hypertension (p=0.005, pC=0.004, OR=24.6, EF=38.3%) and HLA-A2 on patients with pulmonary involvement (p=0.034, pC=0.036, OR=3.67, EF=40.4%) when compared to patients without these clinical manifestations.

Conclusion
These data confirm HLA-B52 as a relevant susceptibility allele for Takayasu's arteritis and suggest that HLA-B15 could be important as a marker of the disease in Mexican patients. Other class I and/or class II alleles could also be relevant as markers for the clinical features present in these patients.

Key words
Major histocompatibility complex (MHC), HLA antigens, Takayasu's arteritis, Mexican Mestizo population.

The present work was supported in part by grants from the Consejo Nacional de Ciencia y Tecnologóa (CONACYT), México.

Please address correspondence to: Dr. Gilberto Vargas-Alarcón, Department of Physiology, Instituto Nacional de Cardiología "Ignacio Chávez", Juan Badiano no. 1, Col. Sección XVI, Tlalpan 14080, México D.F.
E-mail: gvargas63@yahoo.com