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%. Objectives: 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.

1.
Bansil RI, Turner BS: Mucin structure, aggregation, physiological functions and biomedical applications. Curr Opin Colloid Interface Sci 2006;11:164-170.
2.
Mall AS: Analysis of mucins: role in laboratory diagnosis. J Clin Pathol 2008;61:1018-1024.
3.
Bafna S, Kaur S, Batra SK: Membrane-bound mucins: the mechanistic basis for alterations in the growth and survival of cancer cells. Oncogene 2010;29:2893-2904.
4.
Lopez C: Lipid domains in the milk fat globule membrane: specific role of sphingomyelin. Lipid Tech 2010;22:175-178.
5.
Naarding MA, Ludwig IS, Groot F, Berkhout B, Geijtenbeek TB, Pollakis G, Poxton WA: Lewis X component in human milk binds DC-SIGN and inhibits HIV-1 transfer to CD4+ T lymphocytes. J Clin Iinvest 2005;115:3256-3264.
6.
Rossi EA, McNeer RR, Price-Schiavi SA, Van den Brande JM, Komatsu M, Thompson JF, Carraway CA, Fregien NL, Carraway KL: Sialomucin complex, a heterodimeric glycoprotein complex. Expression as a soluble, secretable form in lactating mammary gland and colon. J Biol Chem 1996;271:33476-33485.
7.
Zhang J, Perez A, Yasin M, Soto P, Rong M, Theodoropoulos G, Carraway CA, Carraway KL: Presence of MUC4 in human milk and at the luminal surfaces of blood vessels. J Cell Physiol 2005;204:166-177.
8.
Habte HH, Kotwal GJ, Lotz ZE, Tyler MG, Abrahams M, Rodriques J, Kahn D, Mall AS: Antiviral activity of purified human breast milk mucin. Neonatology 2007;92:96-104.
9.
Schroten H, Hanisch FG, Plogmann R, Hacker J, Uhlenbruck G, Nobis-Bosch R, Wahn V: Inhibition of adhesion of S-fimbriated Escherichia coli to buccal epithelial cells by human milk fat globule membrane components: a novel aspect of the protective function of mucins in the nonimmunoglobulin fraction. Infect Immun 1992;60:2893-2899.
10.
Habte HH, Mall AS, de Beer C, Lotz ZE, Kahn D: The role of crude human saliva and purified salivary MUC5B and MUC7 mucins in the inhibition of Human Immunodeficiency Virus type 1 in an inhibition assay. Virol J 2006;3:99.
11.
Habte HH, de Beer C, Lotz ZE, Roux P, Mall AS: Anti-HIV-1 activity of salivary MUC5B and MUC7 mucins from HIV patients with different CD4 counts. Virol J 2010;7:269.
12.
Habte HH, de Beer C, Lotz ZE, Tyler MG, Kahn D, Mall AS: Inhibition of human immunodeficiency virus type 1 activity by purified human breast milk mucin (MUC1) in an inhibition assay. Neonatology 2008;93:162-170.
13.
Mall AS, Sellers LA, Allen A: Purification of pig duodenal mucus glycoprotein from protein and nucleic acids. Biochem Soc Trans 1987;15:1047-1048.
14.
Lowry OH, Rosebrough NJ, Farr AL, Randall RJ: Protein measurement with the Folin phenol reagent. J Biol Chem 1951;193:265-275.
15.
Mantle M, Allen A: A colorimetric assay for glycoproteins based on the periodic acid/Schiff stain [proceedings]. Biochem Soc Trans 1978;6:607-609.
16.
Mall AS, McLeod HA, Hickman R, Kahn D, Dent DM: Fragmentation pattern of mucins in normal and diseased gastric mucosae: a glycoprotein fractionates with gastric mucins purified from mucosal scrapings of cancer and peptic ulcer patients. Digestion 1999;60:216-226.
17.
Mall AS, Tyler M, Lotz Z, Davidson A, Rodrigues J, van der Watt G, Kahn D, Govender D: The characterisation of mucin in a mature ovarian teratoma occurring in an eight year old patient. Int J Med Sci 2007;4:115-123.
18.
Snary D, Allen A: Studies on gastric mucoproteins. The isolation and characterization of the mucoprotein of the water-soluble mucus from pig cardiac gastric mucosa. Biochem J 1971;123:845-853.
19.
Nagashunmugam T, Friedman HM, Davis C, Kennedy S, Goldstein LT, Malamud D: Human submandibular saliva specifically inhibits HIV type 1. AIDS Res Hum Retroviruses 1997;13:371-376.
20.
Peacocke J, Lotz Z, de Beer C, Roux P, Mall AS: The role of crude saliva and purified salivary mucins in the inhibition of the Human Immunodeficiency Virus type 1. Virol J 2012;9:177.
21.
Kazmi SH, Naglik JR, Sweet SP, Evans RW, O'Shea S, Banatvala JE, Challacombe SJ: Comparison of human immunodeficiency virus type 1-specific inhibitory activities in saliva and other human mucosal fluids. Clin Vaccine Immunol 2006;13:1111-1118.
22.
McGuckin MA, Walsh MD, Hohn BG, Ward BG, Wright RG: Prognostic significance of MUC1 epithelial mucin expression in breast cancer. Hum Pathol 1995;26:432-439.
23.
Mantle M, Forstner GG, Forstner JF: Biochemical characterization of the component parts of intestinal mucin from patients with cystic fibrosis. Biochem J 1984;224:345-354.
24.
Creeth JM: Constituents of mucus and their separation. Br Med Bull 1978;34:17-24.
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