Insulin-like growth factor binding proteins and mitogenic activity of partially fractionated sheep amniotic fluid

Amniotic Fluid Transplantation Alleviates Hematopoietic Deficits in Experimental Rat Aplastic Anemia

Background

Hematopoietic stem cell (HSC) transplantation is the most effective therapy for hematopoietic impairment. However, maintenance and self-renewal of HSCs in culture is still a central focus of HSC research. It is known that amniotic fluid contains a heterologous population of stem cells (AFSCs) and nutrients as well as various types of growth factors. We hypothesize that AFSCs may be expanded in vitro in pure amniotic fluid.

Material/Methods

Amniotic fluid with transparent appearance was harvested at embryo age of 13.5–15.5 days in rats and was placed in a cell culture CO₂ incubator. The cell number in the amniotic fluid was counted before and after culture of amniotic fluid. Then, the effect of amniotic fluid transplantation on 5-fluorouracil combined with busulfan induced-rat aplastic anemia was investigated.

Results

We found that after a short time (about 30 min) culture, the number of AFSCs expanded more than 100-fold. Flow cytometry showed that there was a population of cells expressing hematopoietic markers CD45 and CD34 in addition to a higher proportional of mesenchymal stem cells (MSCs) markers CD29 and CD90. Transplantation of the expanded AFSCs possessed significant therapeutic effect in toxic chemicals induced-aplastic anemia rats, manifested by decreasing animal mortality and alleviating the reduction of the 3 lineages of hematopoietic cells in blood.

Conclusions

Our observation for the first time demonstrates that amniotic fluid is an excellent medium for stem cells to maintain “stemness” proliferation and provides novel evidence to support the potential use of in vitro-expanded AFSCs for the treatment of hematopoietic disorders.

Potential function of amniotic fluid in fetal development---novel insights by comparing the composition of human amniotic fluid with umbilical cord and maternal serum at mid and late gestation

BACKGROUND

Amniotic fluid (AF) is a dynamic and complex mixture. Up to now, little is known about the physiological functions of AF in the process of fetal development. We suppose that AF carries components such as proteins or peptides, which contribute to the regulation of fetal development.

METHODS

Compositions including biochemical components and tumor markers were determined in human AF, umbilical cord serum (UCS) and maternal serum (MS) from the same subject in the range of 15-42 weeks of gestation.

RESULTS

(1) The levels of primary electrolytes such as sodium, chloride, anion gap and osmotic pressure in AF was almost the same as in UCS and MS. (2) The levels of organic substances, including total protein, glucose, triglycerides, cholesterol and various enzymes, were markedly lower in AF than in UCS and MS, especially for total protein, which was 8- and 12.5-fold lower in AF than in UCS and MS, respectively. (3) The levels of tumor markers, including carcinoembryonic antigen, ferritin, cancer antigen 125 and 199, and alpha-fetoprotein in AF displayed different dynamic changes compared to UCS and MS as gestation advanced.

CONCLUSION

This study demonstrated that AF is not a result of simple filtration from the blood but an independent fluid. We speculate that proteins or peptides in the amniotic fluid modulate the process of fetus development since they possess potent bioactivity on cellular growth and proliferation. AF provides a pathway to transport these "regulators" to the fetus and thus plays a pivotal role in fetal development.