ASSOCIATION OF HLA-DQ AND HLA-DR ALLELES WITH SUSCEPTIBILITY OR RESISTANCE TO HIV-1 INFECTION AMONG THE POPULATION OF CHACO PROVINCE, ARGENTINA


		MEDICINA - Volumen 62 - Nº 3, 2002 MEDICINA (Buenos Aires) 2002; 62: 245-248

		HLA class II and susceptibility/resistance to HIV ASSOCIATION OF HLA-DQ AND HLA-DR ALLELES WITH SUSCEPTIBILITY OR RESISTANCE TO HIV-1 INFECTION AMONG THE POPULATION OF CHACO PROVINCE, ARGENTINA PATRICIA MOTTA1, KARINA MARINIC1, ADRIAN SORRENTINO2, ROXANA LOPEZ3, ERNESTO ILIOVICH3,ALICIA HABEGGER DE SORRENTINO1 1Laboratorio de Histocompatibilidad e Inmunogenética, 2Servicio de Inmunología, 3Servicio de Infectología, Hospital Julio C. Perrando, Resistencia, Chaco Abstract The pathogenesis of infections clearly involves immunoregulatory host factors and products of Major Histocompatibility Complex (MHC) genes class II which present antigenic peptides to the T-cell receptor on CD4+ cells which in turn increase the production of specific antibodies and cytotoxic T lymphocytes. The objective of this study was to determine the frequency of the different alleles of HLA class II DQ and DR in HIV-1 infected patients of Caucasians with Guaraní and Toba genetic backgrounds in an effort to determine the prevalence of certain alleles which could signify a factor of susceptibility to or protection against HIV-1 infection. A total of 54 HIV-1 positive patients and 46 healthy control subjects participated in the HLA-DQB1 study while 54 HIV-1 (+) patients and 57 healthy controls were analyzed for HLA-DRB1. Both HLA-DQB1 and HLA-DRB1 genotyping were performed using PCR and sequence-specific reverse hybridization oligonucleotide probe and analyzed with the LiPA Key Typing System and LiPA software. HLA-DQB10203(P=0.041) and DRB101(P=0.05) exhibited a decreased frequency in HIV-1 (+) patients while HLA-DRB113 (P=0.017) was observed more frequently. Several studies have reported different findings, depending on the populations analyzed. Our data show that there are HLA class II alleles associated with susceptibility or resistance to HIV-1 infection and that these differ among ethnic groups. We believe that our results differ from the other Caucasians populations due to the ethnic variability of Chaco inhabitants resulting from mixing between Caucasians and South American natives (Guaraníes and Tobas) Key words:HIV-1, MHC, HLA, gene frequency, cytotoxic lymphocytes Resumen* Asociación de los alelos HLA-DQ y HLA-DR con susceptibilidad y/o resistencia a la infección por HIV-1 en la población del Chaco, Argentina. Los linfocitos citotóxicos (CTL) juegan un rol preponderante en el control de las enfermedades virales cuya eficacia depende en gran medida de la interacción con los péptidos presentados en el contexto de moléculas HLA Clase I. Las moléculas HLA Clase II son los elementos de restricción para los LT CD4+, responsables de montar una respuesta humoral y de cooperar con la acción citolítica. El objetivo de este estudio fue determinar la frecuencia de los diferentes alelos de HLA clase II DQ y DR en pacientes infectados por HIV-1 en la Provincia del Chaco con el fin de investigar si la presencia de ciertos alelos puede conferir susceptibilidad o protección a la infección por HIV. Las muestras fueron tipificadas por biología molecular, con la técnica de hibridación reversa con oligonucleótidos secuencia específica (INNO-LiPA) y analizados con LiPA software. Se analizaron 54 muestras de pacientes HIV-1 (+) para HLA-DQ y HLA-DR, 46 controles sanos para HLA-DQ y 57 controles sanos para HLA-DR. Se encontró una menor frecuencia de los alelos HLA-DQB10203 (P=0.041) y DRB101 (P=0.05) en HIV (+) El alelo DRB113 (P=0.017) fue observado más frecuentemente en HIV (+). Nuestros datos indican alelos HLA clase II que podrían estar asociados con susceptibilidad y resistencia a la infección por HIV-1 y que éstos difieren en los distintos grupos étnicos. Pensamos que las diferencias halladas con otras poblaciones caucásicas se deban a que la población chaqueña de origen caucásico tiene una fuerte mezcla con guaraní y toba. Palabras clave:* HIV-1, MHC, HLA, frecuencia génica, linfocitos citotóxicos Postal Address: Dra. Patricia Motta, Hospital Julio C. Perrando, Avenida 9 de Julio 1100, 3500 Resistencia, Chaco, Argentina. Fax: (54-03722) 428933 e-mail: jgwalter@arnet.com.ar Received: 5-XI-2001 Accepted: 14-II-2002 The pathogenesis of infections clearly involves immunoregulatory host factors and products of Major Histocompatibility Complex (MHC) genes class II, which present antigenic peptides to the T cell receptor on CD4+ cells, which in turn increase the production of specific antibodies and cytotoxic T lymphocytes. MHC class I genes encode molecules that present host –or microbe–derived antigenic peptides to cytotoxic CD8 cells, which can attack and eliminate the antigen-presenting cells. The latter peptides are generated in the cytosol, transported across the endoplasmic reticulum by the protein products of TAP genes and assembled with class I heavy and light chains for presentation at the cell surface1-3. Certain HLA antigens have been reported to be more frequent in patients with the acquired immunodeficiency syndrome (AIDS). In addition, different HLA antigens seem to influence the variability of disease progression in patients from different risk groups and ethnic background. However, it has been difficult to establish whether specific HLA alleles are strong or consistent determinants of HIV-1 disease progression in populations. Inconsisten-cies have arisen from differences in ethnicity, small sample sizes in early studies, investigative designs, laboratory techniques, and statistical methods, as well as extreme polymorphism in HLA4-6 Roe et al7 found DQB10603 associated with HIV-1 infection in Caucasians but not African Americans. DQB103032 frequencies indicate a positive association with protection in Caucasians but not African Americans. DQB0201 was observed more frequently in HIV-1(+) than in HIV-1(-) African Americans, suggesting a positive association with HIV-1 infection in this ethnic group. HLA-DRB04 exhibited a positive association with HIV-1 infection in Caucasians. Rohowsky-Kochan et al8 report prevalence significantly higher of DQ7 in HIV-1(+) compared to seronegative Black and Hispanic individuals. The frequency of DQ4 was significantly elevated in the Black seronegatives. The objective of this study was to determine the frequency of the different HLA class II DQ and DR alleles in HIV-1 infected patients in Chaco Province, Argentina, in an effort to detect the presence of certain alleles that could be a factor of susceptibility to or protection against HIV-1 infection. Material and Methods A total of 54 HIV-1(+) patients and 46 healthy individuals were analyzed for HLA-DQB1and 54 HIV-1(+) patients and 57 healthy subjects for HLA-DRB1. All of them belonged to Cau-casians with Guaraní and Toba genetic backgrounds living in Chaco Province. The DNA samples obtained from peripheral blood were prepared by the salting-out method and then resuspended in distilled water. The HLA-DQB1 and HLA-DRB1 genotyping was performed using PCR and sequence-specific oligonucleotide probe reverse hybridization (LiPA Key Typing System) and analyzed with the LiPA software. Statistical analysis: The objective of the analysis was to examine the association between allele prevalence and HIV-1 seroposivity. For each allele, the proportion of HIV-1 positive patients and control subjects was compared using the gene frequency (GF), which was calculated as GF=1- Ö1-AF; AF (antigen frequency) was calculated by using Haldane’s method. The degree of association between an HLA allele was expressed as the odds ratio (OR), which was calculated according to Woolf’s formula, and P was determined by c2 analysis or, when appropriate, by Fisher’s exact test or Yates correction. P < 0.05 was considered significant9. Results The gene frequency of HLA class II alleles among positive patients was compared with healthy controls, 54 HIV-1 positive patients and 46 healthy individuals were analyzed for HLA-DQB1 and were studied 54 HIV-1 positive patients and 57 healthy individuals for HLA-DRB1 of Caucasians with Guaraní and Toba genetic backgrounds living in Chaco Province, Argentina. Tables 1 and 2 show the distribution of DQ and DR alleles in HIV-1(+) patients and control subjects, ORs, P and c2 values for alleles that present significant difference with respect to the healthy population. The OR for DQB1203(0.18) was decreased with P significant P=0.041 whereas the OR DQB1402(4.40) was elevated, without P statistically significant (P=0.10). With regard to the DR locus, allele DRB1* 13 occurred more frequently among HIV-positive patients than among control subjects (OR =3.33; P=0.017) and allele DRB101 (OR=0.35; P=0.050) occurred less frequently in the same population. Discussion The increased or decreased frequency of certain alleles in HIV-1(+) patients, compared with control subjects, would suggest that they are a factor in susceptibility to or protection against the viral infection. Several studies reported different findings, depending on the populations analyzed. We determined alleles of the HLA class II (DQ and DR) in order to understand if these genetic factors are associated with susceptibility or resistance to HIV-1 infection among a population in Chaco Province of Northeast Argentina (Caucasians with Guaraní and Toba genetic backgrounds). We observed that DRB113(P=0.017) occurred more frequently among HIV-1(+) patients than among controls suggesting that it plays a role in susceptibility to HIV-1 infection. Winchester et al10 reported the transmission of HIV-1 from an infected woman to her offspring during gestation and delivery was found to be influenced by the infant’s major histocompatibility complex class II DRB1 alleles. One or more DR13 alleles, including DRB11301, 1302, and 1303, were found in 31.7% of seroreverting infants and 15.2% of those becoming HIV-infected (OR=2.6 P=0.048). This association was influenced by ethnicity, being seen more strongly among the 80 Black and Hispanic children (OR=4,3; P=0.023), with the most pronounced effect among Black infants where 7 of 24 seroreverters inherited these alleles as compared to none among 12 HIV-infected infants (OR=12.3; P=0.037). The previously recognized association of DR13 alleles with some situations of long-term nonprogression of HIV suggests that similar mechanisms may regulate both the occurrence of infection and disease progression after infection. Upon examining for residual associations, only the DR2 allele DRB11501 was associated with seroreversions in Caucasoid infants (OR=24; P=0.004). Among Caucasoid the DRB103011 allele was positively associated with the occurrence of HIV infection (P=0,03)10. We noted a decreased frequency in the alleles DQB1203(P=0.041) and DRB101(P=0.05) among HIV-1 (+) compared with control subjects which would suggest that they are a factor in protection against the viral infection. MacDonald11 observed that resistance to HIV-1 infection was independently associated with HLA-DRB101(IRR, 0.22; 95% CI; 0.06-0.60; p=0.0003) which suggests that anti-HIV-1 class II restricted CD4 effector mechanisms may play an important role in protecting against viral challenge. On the other hand, Roe et al7 found DQB10603 and DRB104 in a positive association with HIV-1 infection in Caucasians but not in African Americans, while DQB10201 was observed more frequently in HIV-1 positive than HIV-1 negative Afri- can Americans, suggesting protection against HIV. DQB103032 frequencies indicating a positive association with protection from HIV-1 infection in Caucasians. Other authors observed that HLA markers associated with possible protection from infection for African Americans were Cw4 and DRw6, whereas Caucasians expressed none12. Just et al13 studying the role of host genotype in pediatric infection with HIV-1 and progression to AIDS, described the presence of DQB10604 associated with increased risk of HIV infection. In Italy, a higher frequency of HLA-A2 has been reported in HIV-1(+) patients, compared with HIV-1 seronegatives, at-risk patients (patients with hemophilia), whereas HLA-B52 and DR4 were decreased in HIV-1 positive patients14. Other authors informed that the frequency of DQ4 was significantly elevated in the Black seronegatives and report prevalence significantly higher of DQ7 in HIV-1 (+) compared to seronegatives Black and Hispanic individuals8. We observed that OR for DQB10402 (4.40) was elevated, without P statistically significant (P=0.10). In conclusion, our data show that there are HLA class alleles associated with susceptibility (DRB113) or resistance (DQB10203 and DRB101) to HIV1(+) infection and that these differences among ethnic groups provide additional evidence that HLA polymorphism may confer a genetic risk or protection for HIV-1 infection. We believe that our results differ from those described in the literature due to the ethnic variability of Chaco inhabitants resulting from the mixing among Caucasians and South American natives (Guaraníes and Tobas). References* 1. Klein MR, van Baalen CA, Holwerda AM, et al. Kinetics of gag-specific cytotoxic T lymphocyte responses during the clinical course of HIV-1 infection: A longitudinal analysis of rapid progressors and long-term asymptomatics. J Exp Med 1995; 181: 1365-72. 2. Rowland-Jones S, Sutton J, Ariyoshi K, et al. HIV-specific cytotoxic T cells in HIV-exposed but uninfected Gambian women. Nat Ed 1995,1: 59-64. 3. Becker Y.HIV-1 proteins in infected cells determine the presentation of viral peptides by HLA class I and class II molecules and the nature of the cellular and humoral antiviral immune responses. Virus Genes 1994; 8: 249-70. 4. Keet IPM, Klein MR, Just JJ, Kaslow RA. The role of host genetics in the natural history of HIV-1 infection: the needle the haystack. AIDS 1996; 10: Klein S59-67. 5. Just JJ. Genetic predisposition to HIV-1 infection and acquired immunodeficiency virus syndrome. Hum Immunol 1995; 44: 156-69. 6. Hill AVS. HIV and HLA: confusion or complexity? Nat Med 1996; 2:395-6. 7. Roe DL, Lewis RE, Cruse JM. Association of HLA-DQ and -DR alleles with protection from or infection with HIV-1. Exp Mol Pathol 2000; 68: 21-8. 8. Rohowsky-Kochan C, Skurnick J, Molinaro D, Louria D. HLA Antigens Associated with Susceptibility/Resistance to HIV-1 Infection. Human Immunology 1998; 59: 802-15. 9. Elston RC, Johnson WD. In: Lowenthal D, ed. Principios de Bioestadística. México City: Manual Moderno, 1990: 145-9. 10. Winchester R, Chen Y, Rose S, Selby J, Borkowsky W. Major histocompatibility complex class II DR alleles DRB11501 and those encoding HLA-DR13 are preferen-tially associated with a diminution in maternally transmitted human immunodeficiency virus 1 infection in different ethnic groups: determination by an automated sequence-based typing method. Proc Natl Acad Sci USA* 1995; 92: 12374-8. 11. MacDonald KS, Fowke KR, Kimani J, Dunand VA, Nagelkerke NJ, Ball TB, et al. Influence of HLA supertypes on susceptibility and resistance to human immunodefi-ciency virus type 1 infection. J Infect Dis 2000; 181: 1581-9. 12. Cruse JM, Brackin MN, Lewis RE, Meeks W, Nolan R, Brackin B. HLA disease association and protection of HIV infection among African Americans and Caucasians. Pathobiology 1991; 59: 324-8. 13. Just JJ, Abrams E, Louie LG, et al. Influence of host genotype on progression to acquired immunodeficiency Syndrome among children infected with human immuno-deficiency virus type 1. J Pediatric 1995; 127: 544-9. 14. Fabio G, Smeraldi RS, Gringeri A, Marchini M, Bonata P, Mannucci PM. Susceptibility to HIV infection and AIDS in Italian haemophiliacs is HLA associated. Br J Haematol 1990; 75: 531-6. Table 1.– Distribution of HLA-DQ alleles among 54 human immunodeficiency virus (HIV)-positive patients and 46 control subjects HIV (+) Controls Allele n GF(%) N GF(%) P* OR DQB10201/0202 19 19.5 17 20.6 DQB10203 2 1.9 8 9.1 0.041* 0.18 DQB103011/03012/ 0309 20 20.6 16 19.2 DQB10302/0307 15 15.0 12 14.0 DDQB103032/03033/0306 4 3.8 7 7.9 DQB10304 2 1.9 3 3.3 DQB10402 9 8.7 2 2.2 0.10* 4.40 DQB105011 9 8.7 8 9.1 DQB10502 0 0 1 1.1 DQB105031 1 0.9 2 2.2 DQB106011/06013 3 2.8 2 2.2 DQB10602/0611 6 5.7 5 5.6 DQB10603/0614 10 9.7 4 4.4 DQB10604 5 4.7 4 4.4 DQB10607 2 1.9 0 0 DQB10613 0 0 1 1.1 GF, gene frequency; OR, odds ratio. Fisher’s exact 2-tailed test; ** Yates correction. Table 2.– Distribution of HLA-DR alleles among 54 human immunodeficiency virus (HIV)-positive patients and 57 control subjects HIV (+) Controls Allele n GF(%) n GF(%) P OR DRB101 7 6.7 17 16.2 0.050 0.35 DRB103 9 8.7 8 7.3 DRB104 31 34.7 27 27.5 DRB107 14 13.9 13 12.1 DRB108 5 4.7 6 5.4 DRB109 0 0 3 2.7 DRB110 2 1.9 2 1.8 DRB111 4 3.8 9 8.2 DRB112 1 0.9 0 0 DRB113 19 19.5 8 7.3 0.017 3.33 DRB114 6 5.7 5 4.5 DRB115 6 5.7 10 9.2 DRB116 4 3.8 6 5.4 GF, gene frequency; OR, odds ratio. Yates correction.