Immunological aspects of human amniotic fluid cells: Implication for normal pregnancy

Abstract

Amniotic fluid cells (AFCs) are routinely obtained and expanded in vitro for prenatal diagnosis; nevertheless current knowledge about their properties is limited. The detailed mechanisms underlying normal pregnancies are yet to be discovered. The goal of this study was to identify the immunological aspects of AFCs including cytokine production and human leukocyte antigen (HLA) expression, and to discuss its implication for pregnancy. Eighty-six samples of AFCs were determined for HLA expression before and after culture. Cytokine production was measured with flow cytometry in AFC culture supernatants. Treatment of interferon (IFN)-gamma on induction of HLA-DR expression in cultured AFCs was also investigated. Data indicated that both fresh and cultured AFCs express HLA-I, HLA-G, but not HLA-DR, and the cultured AFCs predominately produce the cytokine interleukin (IL)-6. Importantly, we observed that IFN-gamma could induce HLA-DR expression on cultured AFCs in a dose-dependent manner. Taken together, our results indicated that AFCs are functionally active cells and are significant in pregnancy.

Therapeutic potential of a distinct population of human amniotic fluid mesenchymal stem cells and their secreted molecules in mice with acute hepatic failure

“…HPL cell transplantation was even more effective than treatment with AF-MSCs and successfully downregulated the systemic inflammation, as determined by measuring serum levels of IL-10, IL-2, IFNγ and TNFα. Furthermore, in vitro studies showed that HPL cells retained the same expression levels of HLA antigens as AF-MSCs, as reported previously 39. However, we cannot exclude the possibility that the HPLs, as cells induced to undergo hepatogenesis in culture, may also include a small percentage of other cell types.…”

Amniotic fluid soluble human leukocyte antigen-G in term and preterm parturition, and intra-amniotic infection/inflammation

“…[66] It has been proposed that production of soluble HLA-G may occur in amnion and decidual trophoblast cells[177] and amnion epithelium. [178] Recently, it has been shown that fresh and cultured amniotic fluid cells express soluble forms of HLA-I and HLA-G.[179,180] Interestingly, both shed HLA-G1 and HLA-G5 have been detected in different body fluids such as serum from pregnant and non-pregnant women, patients with cancer or transplants, and even in plasma from men. [73,74,111,181,182] This suggest that, beside trophoblast, circulating HLA-G may have other sources.…”

Amniotic Membrane and Amniotic Fluid-Derived Cells: Potential Tools for Regenerative Medicine?

“…Studies investigating the immunological features of human amniotic fluid-derived cells show that these cells weakly express HLA Class I and -G, but not HLA-DR. Production of IL-6 [144,145] has also been observed during culture of these cells, while expression of HLA-DR could be induced after treatment with IFN-γ [145].…”