Exploring the stem cell and non-stem cell constituents of human breast milk

Abstract

The immense potency of nutritional components of human breast milk and importance of breastfeeding is known worldwide. Recent researches had identified stem cells as integral component of human breast milk. Nevertheless, there is little proof of evidence on the stem cell constituents of breast milk. It is imperative to explore the cellular constituents of human breast milk, including of stem cells, to open new avenue in child's development and regeneration. Thus, we aimed at identifying the cellular constituents of human breast milk by phenotypic characterisation of diverse cell surface markers of hematopoietic stem cells (CD 34, CD 133, CD 117), mesenchymal stem cells (CD 90, CD 105, CD 73), myoepithelial cells (CD 29, CD 44), Immune cells (CD 209, CD 86, CD 83, CD 14, CD 13, HLADR, CD 45), as well as cell adhesion molecules (CD 31, CD 54, CD 166, CD 106, CD 49d), and other markers (ABCG2, CD140b) using flowcytometry. We found a lower expression of CD 34 (13.07 ± 2.0 %), CD 90 (7.79 ± 0.8 %) and CD 73 (2.19 ± 0.41 %), indicating scanty hematopoietic and mesenchymal stem cell population in human breast milk. On contrary, myoepithelial progenitors, cell adhesion molecules, immune cells and growth factors were identified as the major constituents of breast milk. Overall, this study illuminates the benefits of breast feeding as breast milk encompasses heterogeneous cellular components that benefits child's growth, immunity and development. However, further research on these constituents of human breast milk will widen their applicability in treatment of neonatal disorders.

Novel DRAQ5™/SYTOX® Blue Based Flow Cytometric Strategy to Identify and Characterize Stem Cells in Human Breast Milk

“…Flow cytometry has provided insight to cellular breast milk composition and stem cells have been found in breast milk (5,12,13). Human breast milk contains heterogeneous populations of cells with high variability related to individual factors as well as the stage of lactation.…”

Human Milk Composition

“…In women infected with HIV-1 and HTLV-1, however, the activity of these cells unfortunately enables mother to infant viral transmission (see article by Lawrence in this issue). Stem cells have also been identified in human milk; 88,90 their function is under investigation.…”

At the Dawn of a New Discovery: The Potential of Breast Milk Stem Cells

“…It is noteworthy that CK18/CK14 double-positive cells can also be found in breast milk (F. Hassiotou, unpublished data), potentially suggesting the presence of progenitors (35) and highlighting the fact that care must be taken in interpreting tissue immunostaining and milk flow cytometry data, because the markers currently known to distinguish different mammary cell populations are not definitive. For example, Indumathi et al also reported the presence of myoepithelial cells in colostrum, but the markers used to identify these and other cell types were not myoepithelial cell-specific (36).…”

“…In addition, preliminary investigations indicate the presence of CD34 + hematopoietic stem/progenitor cells in colostrum and breast milk (14,36), which almost certainly originate from the maternal bloodstream. The properties of these cells, the mechanisms of their transfer into breast milk, and their roles remain to be established.…”

“…A few studies suggested that human milk contains mesenchymal stem cells (MSCs) based on markers known to be expressed by MSCs, such as STRO-1, CD90, CD105, and CD73 (14,36), and the potential of breast milk-derived cells to differentiate in culture into mesodermal cells, such as osteoblasts, chondrocytes, and adipocytes, a known feature of MSCs (17). However, caution should be exercised when interpreting these data.…”