Differentiation of Hematopoietic Stem Cells

Differentiation of Hematopoietic Stem Cells

Abstract

Research on stem cells results of high interest in the current days. Due to pluripotency, the application of specific protocols for cell differentiation allows the generation of a significant variety of specialized cells from stem cells. In this lab we examined the differentiation of stem cells into different cell types. Each treatment group consisted of two slides. Half of the slides were stained for the presence of neutrophils and macrophages, while the other half were stained for the presence of erythrocytes. The four slides stained for the presence of neutrophils and macrophages were immersed in a Coplin jar filled with May-Grunwald stain for 2-3 minutes. The four slides stained for the presence of erythrocytes was immersed in a Coplin jar with o-dianisidine solution for 10 minutes and were rinsed in a jar of dH20. We followed the same procedure for the slides stained for neutrophils and macrophages for the remaining act of staining the slide for the presence of erythrocytes. Following the staining of the slides, we prepared each slide for examination under the microscope and in hope that they would show us which cytokine is responsible for yielding each cell lineage.

Introduction

Stem cells, a potential medical breakthrough in its capacity for the regeneration of body parts, consists of cells presented in early development or in adult life. They can "give rise to the specialized or differentiated cells that carry out the specific functions of the body, such as skin, blood, muscle, and nerve cells" (Understanding), and they are involved in its replication or differentiation into different cell types. Differentiation, the process by which different cell types arise to lead cells with specific structures and functions, is a significant factor in the pursuit of stem cell research.

The two different sources of stem cells are embryonic and adult stem cells: ranging from totipotent, pluripotent, and multipotent stem cells. Totipotent cells possess the genetic information to form an entire individual, pluripotent cells retain the ability to form all of the cells, and multipotent cells have the ability to differentiate into a limited number of cell types. Hematopoietic stem cells, one of two different kinds of multipotent stem cells, differentiates into a variety of red and white blood cells: erythrocytes, macrophages, and neutrophils. They are distinguished in their process of cell differentiation.

As described in Life: the Science of Biology, erythrocytes, or red blood cells, differentiate through a process called erythropoiesis. It is controlled by the hormone, erythropoietin, which is released due to hypoxia, or insufficient oxygen. Macrophages, or white blood cells, differentiate when "circulating blood monocytes migrate from the vasculature into the extravascular compartment under the influence of many different endogenous and exogenous factors" (Differentiation). Neutrophils, another type of white blood cells, differentiate through a multipotent hematopoietic stem cell, a multipotent hemophilic progenitor, and a common myeloid progenitor. Neutrophils stimulate inflammation, and macrophages engulf and digest microorganisms and activate T cells. The objective of this lab was to familiarize us with stem cells and to show us how