Human milk oligosaccharide concentration and risk of postnatal transmission of HIV through breastfeeding.
BACKGROUND
The inefficiency of HIV breast-milk transmission may be caused by the presence of immunologically active factors, including human milk oligosaccharides (HMOs).


OBJECTIVE
We investigated whether HMO concentrations are associated with a reduced risk of postnatal HIV transmission.


METHODS
A nested case-control study was conducted within a larger cohort study of HIV-infected women and their infants followed from birth to 24 mo in Lusaka, Zambia. Breast-milk samples collected at 1 mo from 81 HIV-infected women who transmitted via breastfeeding, a random sample of 86 HIV-infected women who did not transmit despite breastfeeding, and 36 uninfected breastfeeding women were selected. Total and specific HMO concentrations were measured by HPLC and compared between groups with adjustment for confounders by using logistic regression.


RESULTS
HIV-infected women with total HMOs above the median (1.87 g/L) were less likely to transmit via breastfeeding (OR: 0.45; 95% CI: 0.21, 0.97; P = 0.04) after adjustment for CD4 count and breast-milk HIV RNA concentrations; a trend toward higher concentrations of lacto-N-neotetraose being associated with reduced transmission (OR: 0.49; 95% CI: 0.23, 1.04; P = 0.06) was also observed. The proportion of 3'-sialyllactose (3'-SL) per total HMOs was higher among transmitting than among nontransmitting women (P = 0.003) and correlated with higher plasma and breast-milk HIV RNA and lower CD4 counts. Neither Secretor nor Lewis status distinguished between transmitting and nontransmitting women.


CONCLUSIONS
Higher concentrations of non-3'-SL HMOs were associated with protection against postnatal HIV transmission independent of other known risk factors. Further study of these novel, potentially anti-HIV components of breast milk is warranted.
Division of Neonatology and the Division of Pediatric Gastroenterology and Nutrition, Department of Pediatrics, University of California, San Diego, CA, USA. lbode@ucsd.edu
Lars
L
Bode
Louise
L
Kuhn
Hae-Young
HY
Kim
Lauren
L
Hsiao
Caroline
C
Nissan
Moses
M
Sinkala
Chipepo
C
Kankasa
Mwiya
M
Mwiya
Donald M
DM
Thea
Grace M
GM
Aldrovandi
D000328:Adult; D001942:Breast Feeding; D018791:CD4 Lymphocyte Count; D016022:Case-Control Studies; D015331:Cohort Studies; D015986:Confounding Factors, Epidemiologic; D005260:Female; D006678:HIV / Q000472:pathogenicity*; D015658:HIV Infections / Q000097:blood / Q000453:epidemiology / Q000635:transmission*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007774:Lactation; D007983:Lewis Blood Group Antigens / Q000378:metabolism; D008297:Male; D008895:Milk, Human / Q000737:chemistry* / Q000378:metabolism / Q000821:virology*; D009844:Oligosaccharides / Q000032:analysis* / Q000378:metabolism; D012367:RNA, Viral / Q000032:analysis / Q000097:blood; D012306:Risk; D055815:Young Adult; D015024:Zambia / Q000453:epidemiology
C421467:3'-sialyllactose; D007983:Lewis Blood Group Antigens; D009844:Oligosaccharides; D012367:RNA, Viral; C013084:lacto-N-neotetraose