Human leukocyte antigen (HLA) B*18 and protection against mother-to-child HIV type 1 transmission.
Human leukocyte antigen (HLA) molecules regulate the cellular immune system and may be determinants of infant susceptibility to human immunodeficiency virus type 1 (HIV-1) infection. Molecular HLA typing for class I alleles was performed on infants followed in a Kenyan perinatal cohort. Early HIV-1 infection status was defined as infection occurring at birth or month 1, while late infection via breast milk was defined as first detection of HIV-1 after 1 month of age. Likelihood ratio tests based on a proportional hazards model adjusting for maternal CD4 T cell count and HIV-1 viral load at 32 weeks of gestation were used to test associations between infant allelic variation and incident HIV-1 infection. Among 433 infants, 76 (18%) were HIV-1 infected during 12 months of follow-up. HLA B*18 was associated with a significantly lower risk of early HIV-1 transmission [relative risk (RR) = 0.26; 95% confidence interval (CI) 0.04-0.82], and none of the 24 breastfeeding infants expressing HLA B*18 who were uninfected at month 1 acquired HIV-1 late via breast milk. We observed a trend toward increased early HIV-1 acquisition for infants presenting HLA A*29 (RR = 2.0; 95% CI 1.0-3.8) and increased late HIV-1 acquisition via breast milk for both Cw*07 and Cw*08 (RR = 4.0; 95% CI 1.0-17.8 and RR = 7.2; 95% CI 1.2-37.3, respectively). HLA B*18 may protect breast-feeding infants against both early and late HIV-1 acquisition, a finding that could have implications for the design and monitoring of HIV-1 vaccines targeting cellular immune responses against HIV-1.
Department of Medicine, University of Washington, Seattle, Washington 98104, USA. cfarq@u.washington.edu
Carey
C
Farquhar
Sarah
S
Rowland-Jones
Dorothy
D
Mbori-Ngacha
Mary
M
Redman
Barbara
B
Lohman
Jennifer
J
Slyker
Phelgona
P
Otieno
Elizabeth
E
Obimbo
Timothy
T
Rostron
James
J
Ochieng
Julius
J
Oyugi
Rose
R
Bosire
Grace
G
John-Stewart
D000163:Acquired Immunodeficiency Syndrome / Q000276:immunology* / Q000517:prevention & control; D018791:CD4 Lymphocyte Count; D005260:Female; D015234:HLA-A Antigens / Q000276:immunology; D015235:HLA-B Antigens / Q000276:immunology*; D059911:HLA-B18 Antigen; D015236:HLA-C Antigens / Q000276:immunology; D006650:Histocompatibility Testing; D006801:Humans; D018445:Infectious Disease Transmission, Vertical / Q000517:prevention & control*; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000821:virology*; D019562:Viral Load
D015234:HLA-A Antigens; D015235:HLA-B Antigens; D059911:HLA-B18 Antigen; D015236:HLA-C Antigens