# Angiotensin II promotes erythroid proliferation in a three-stage erythroid culture system

## TL;DR

This study shows that angiotensin II boosts the growth of cultured red blood cell precursors, which could help improve cell production for therapies.

## Contribution

The study demonstrates that angiotensin II enhances erythroid cell proliferation in a 3-stage culture system.

## Key findings

- Angiotensin II receptor is expressed in erythroblasts at all differentiation stages.
- Adding angiotensin II increases the number of cultured erythroid cells significantly.
- Angiotensin II does not affect the enucleation process of erythroid cells.

## Abstract

At present, the numbers of cultured erythroid cells obtained from culture systems are not on a scale that can be used for therapeutics since the cultured erythroid cells have limited proliferation capacity. Stromal cells are believed to play important roles during erythropoiesis. Our previous study shows that factors secreted by stromal cells enhance the proliferation capacity of adult erythroid cells in the culture system. Among the identified factors, angiotensinogen is one of the most abundant proteins secreted by the stromal cells. This study aims to investigate the effect of angiotensin II, an angiotensinogen derivative, on the proliferation of erythroid cells.

•The receptor for angiotensin II was first checked by PCR analysis. It was expressed in erythroblasts at all stages during differentiation.•To study the effect of angiotensin II, CD34+ hematopoietic stem cells were cultured in a 3-stage erythroid culture system with and without angiotensin II. The addition of angiotensin II to the culture media, from day 0 to 8, significantly increases the numbers of cultured erythroid cells, whereas no difference in enucleation is observed.

The receptor for angiotensin II was first checked by PCR analysis. It was expressed in erythroblasts at all stages during differentiation.

To study the effect of angiotensin II, CD34+ hematopoietic stem cells were cultured in a 3-stage erythroid culture system with and without angiotensin II. The addition of angiotensin II to the culture media, from day 0 to 8, significantly increases the numbers of cultured erythroid cells, whereas no difference in enucleation is observed.

Image, graphical abstract