title: Purified human breast milk MUC1 and MUC4 inhibit human immunodeficiency virus.
abstract: BACKGROUND
  The HIV-AIDS pandemic is prevalent in sub-Saharan Africa. Breastfeeding is a risk factor, with transmission from mother to child being as high as 40%.
  
  
  OBJECTIVE
  To determine the antiviral activity of crude breast milk and its purified mucins MUC1 and MUC4 against HIV-1 in patients who were HIV positive compared to those who were not.
  
  
  METHODS
  Twenty-one human milk samples were taken from both groups. Breast milk mucins were purified by density-gradient ultracentrifugation in caesium chloride and analyzed by SDS-PAGE, Western blotting and amino acid content. The inhibition of the virus by crude milk and purified mucin was assayed by an in vitro HIV-1 p24 assay.
  
  
  RESULTS
  SDS-PAGE for purified mucin showed several high-molecular-weight bands for the HIV-negative group and prominently stained single bands on the stacking gel with faintly periodic acid Schiff-positive glycoprotein bands observed in some cases in the running gel for the HIV-positive mucins. Western blot analysis identified the mucins in both groups to be MUC1 and MUC4. Both mucins showed more intensity on Western blotting for the HIV-positive group. There was no difference in the content of serine, threonine and proline of purified mucins for both groups. HIV-1 was not inhibited by crude breast milk from normal (13/14 samples) and infected individuals (19/19 samples). Fifteen of 20 and 16/18 samples of purified mucin from the uninfected and HIV-positive groups, respectively, inhibited the virus.
  
  
  CONCLUSIONS
  Crude breast milk does not inhibit HIV-1, whilst purified mucins do in an in vitro assay.
authors: Division of General Surgery, University of Cape Town, Cape Town, South Africa.
authors: Yolanda
authors: Y
authors: Mthembu
authors: Zoe
authors: Z
authors: Lotz
authors: Marilyn
authors: M
authors: Tyler
authors: Corena
authors: C
authors: de Beer
authors: Jeronimo
authors: J
authors: Rodrigues
authors: Leann
authors: L
authors: Schoeman
authors: Anwar Suleman
authors: AS
authors: Mall
mesh_terms: D019380:Anti-HIV Agents / Q000302:isolation & purification / Q000494:pharmacology*; D002478:Cells, Cultured; D005260:Female; D016655:HIV Core Protein p24 / Q000378:metabolism; D015497:HIV-1 / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000821:virology; D008895:Milk, Human / Q000737:chemistry*; D018396:Mucin-1 / Q000302:isolation & purification / Q000494:pharmacology*; D055264:Mucin-4 / Q000302:isolation & purification / Q000494:pharmacology*; D014779:Virus Replication / Q000187:drug effects
chemical_list: D019380:Anti-HIV Agents; D016655:HIV Core Protein p24; C060192:MUC1 protein, human; C524658:MUC4 protein, human; D018396:Mucin-1; D055264:Mucin-4