Difference Between G CSF and GM CSF

The key difference between G CSF and GM CSF is that G CSF is a colony-stimulating factor that specifically promotes neutrophil proliferation and maturation while GM CSF is a colony-stimulating factor that shows much broader effects on multiple cell lineages, especially on macrophages and eosinophils.

G CSF or granulocyte colony-stimulating factor and GM CSF or granulocyte-macrophage colony-stimulating factor are two hematopoietic growth factors. They are immune modulators as well. Development of molecularly cloned G CSF and GM CSF has increased the safety and efficacy of intensive chemotherapy and radiation therapy in order to reverse damage to bone marrow function. It reduces the infections, bleeding and shortening hospitalization. Moreover, these drugs are important for hematopoietic cell transplants.

1. Overview and Key Difference
2. What is G CSF
3. What is GM CSF
4. Similarities Between G CSF and GM CSF
5. Side by Side Comparison – G CSF vs GM CSF in Tabular Form
6. Summary

What is G CSF?

Granulocyte colony-forming factor or G CSF is a protein produced by the body. It is the most widely used molecularly cloned hematopoietic growth factor. The gene that codes for G CSF is present in chromosome 17. G CSF stimulates bone marrow in order to produce more neutrophils, which are infection-fighting white blood cells. In other words, G CSF helps the bone marrow to make more white blood cells to fight against antigens. It is used to treat patients suffering from certain cancers and neutropenia. It is also used for patients who receive an autologous stem cell transplant.

Figure 01: G CSF

Filgrastim and pegfilgrastim, and their biosimilars are examples of G CSF. Filgrastim is a protein produced in E coli. Therefore, it is a recombinant human G CSF. Similar to filgrastim, lenograstim is another recombinant human G CSF.

What is GM CSF?

Granulocyte macrophage colony-stimulating factor or GM CSF is a hematopoietic growth factor which stimulates the proliferation of granulocytes and macrophages from bone marrow precursor cells. It is a glycoprotein produced by macrophages, T cells, mast cells, natural killer cells, endothelial cells and fibroblasts. The receptors of GM CSF are expressed widely than G CSF receptors.

Figure 02: GM CSF

GM CSF shows a broader range of biologic activities, including antifungal, antibacterial and anti viral properties. GM CSF has much broader effects on multiple cell lineages, especially on macrophages and eosinophils. Sargramostim is a molecularly cloned GM CSF and a glycosylated protein produced in S. cerevisiae. Clinically, GM CSF is used in treatments for neutropenia in cancer patients undergoing chemotherapy, AIDS patients during therapy, and patients after bone marrow transplantation.

What are the Similarities Between G CSF and GM CSF?

G CSF and GM CSF are the two most common types of hematopoietic growth factors.
They are colony-stimulating factors.
They are glycoproteins.
G CSF and GM CSF are given intravenously or subcutaneously.
Both are available commercially in recombinant form for clinical use.
Sources of both factors are endothelial cells, monocytes, macrophages, and fibroblasts.
Both drugs cause an acute, short-lived leukopenia after intravenous administration,

What is the Difference Between G CSF and GM CSF?

The key difference between G CSF and GM CSF is that G CSF is a colony-stimulating factor that specifically promotes neutrophil proliferation and maturation while GM CSF is a colony-stimulating factor that shows much broader effects on multiple cell lineages, especially on macrophages and eosinophils. Moreover, G-CSFR is expressed primarily on neutrophils and bone marrow precursor cells, while GM-CSFR more widely expressed than the G-CSFR.

Below info-graphic lists more differences between G CSF and GM CSF in tabular form.

Summary – G CSF vs GM CSF

Both G CSF and GM CSF are colony-stimulating factors which are important hematopoietic growth factors and immune modulators. G CSF is a glycoprotein that stimulates the bone marrow to produce more white blood cells to fight against infections. More specifically, G CSF promotes neutrophil proliferation and maturation. GM CSF is a glycoprotein that stimulates the proliferation of granulocytes and macrophages from bone marrow precursor cells. Unlike G CSF, GM CSF affects more cells types. Moreover, GM CSF receptors are more widely expressed than G CSF receptors. Furthermore, GM CSF has a broader range of biologic activities than the G CSF. However, both enhance the antimicrobial functions of mature neutrophils. Thus, this is the summary of the difference between G CSF and GM CSF.

Reference:

1. Shiomi, Aoi, and Takashi Usui. “Pivotal Roles of GM-CSF in Autoimmunity and Inflammation.” Mediators of Inflammation, Hindawi, 8 Mar. 2015, Available here.
2. Root, Richard K., and David C. Dale. “Granulocyte Colony-Stimulating Factor and Granulocyte-Macrophage Colony-Stimulating Factor: Comparisons and Potential for Use in the Treatment of Infections in Nonneutropenic Patients.” OUP Academic, Oxford University Press, 1 Mar. 1999, Available here.

Image Courtesy:

1. “GCSF Crystal Structure.rsh” By Ramin Herati – Created from PDB 1RHG and rendered by me using Pymol (Public Domain) via Commons Wikimedia
2. “GMCSF Crystal Structure.rsh” By Ramin Herati – Created from PDB 2GMF and rendered by me using Pymol (Public Domain) via Commons Wikimedia