Amniotic fluid cells: current progress and emerging challenges in renal regeneration

Abstract

Amniotic fluid (AF) contains a heterogeneous population of cells that have been identified to possess pluripotent and progenitor-like characteristics. These cells have been applied in various regenerative medicine applications ranging from in vitro cell differentiation to tissue engineering to cellular therapies for different organs including the heart, the liver, the lung, and the kidneys. In this review, we examine the different methodologies used for the derivation of amniotic fluid stem cells and renal progenitors, and their application in renal repair and regeneration. Moreover, we discuss the recent achievements and newly emerging challenges in our understanding of their biology, their immunoregulatory characteristics, and their paracrine-mediated therapeutic potential for the treatment of acute and chronic kidney diseases.

Concise Reviews: Stem Cells and Kidney Regeneration: An Update

“…Stem cells have different capacities for integrating into target organs, as we showed with AFSC . We found almost no integration in a CKD model (after 5 days) and very low integration in ATN models despite a positive therapeutic signal.…”

“…We demonstrated that stem cells derived from amniotic fluid are renoprotective in animal models of glycerol-induced AKI, as well as CKD [4,37]. AFSC seem to protect tubular and glomerular cells by stimulating endogenous repair mechanisms, thus reducing inflammation and fibrosis [38].…”

“…In this case, the gestational age is an important variable. We derive AFSCs from discarded amniocentesis samples during the first trimester; others collect cells at delivery, obtaining fresh fluid samples but late in gestation . We also believe that clonal isolation of the AFSCs is important for limiting heterogeneity of the cell product.…”

“…We used a clonal population of AFSCs after positive selection for c‐kit. Other groups use AFSCs derived from colony‐forming units or with no selection for any markers . These methodologies for source and derivation of AFSCs could account for the resultant differences in the final product population and functional differences in repair capacity.…”

The renal microcirculation in chronic kidney disease: novel diagnostic methods and therapeutic perspectives

“…Several studies have recently shown that MSCs play an important role in preserving renal microvessels and relieving kidney injury in a variety of kidney disease models (Table 3 ). Furthermore, MSCs can be obtained from a variety of tissues, including adipose tissue [ 101 , 102 ], bone marrow [ 103 – 105 ] and amniotic fluid [ 106 , 107 ], and have been reported to have antioxidative, anti-inflammation, proangiogenic, and immunomodulatory function in numerous experimental studies. More specifically, the functions (including differentiation, immunosuppression, and release of cytokines and factors) of MSCs isolated from adipose tissue of renal disease patients were not affected by exposure to uremic conditions.…”