What is the Difference Between Myeloid and Lymphoid Cells

The main difference between myeloid and lymphoid cells is that myeloid cells give rise to red blood cells, granulocytes, monocytes, and platelets whereas lymphoid cells give rise to lymphocytes and natural killer cells. 

In brief, myeloid and lymphoid cells are two types of multipotent, hematopoietic progenitor cells, which give rise to the cells in the blood. Furthermore, myeloid cells refer to the cells derived from the bone marrow while lymphoid cells refer to the cells related to the lymphatic system.

Key Areas Covered

1. What are Myeloid Cells
     – Definition, Types of Blood Cells, Malignancies
2. What are Lymphoid Cells
     – Definition, Types of Blood Cells, Malignancies
3. What are the Similarities between Myeloid and Lymphoid Cells
     – Outline of Common Features
4. What is the Difference Between Myeloid and Lymphoid Cells
     – Comparison of Key Differences

Key Terms

Granulocytes, Hematopoiesis, Lymphoid Cells, Lymphocytes, Monocytes, Myeloid Cells, NK Cells, Red Blood cells

What are Myeloid Cells

Myeloid cells are a type of multipotent, hematopoietic progenitor cells that occur in the bone marrow. They give rise to several types of blood cells including red blood cells, granulocytes such as neutrophils, eosinophils, basophils, monocytes, and platelets.

• Red blood cells – the most common type of blood cells responsible for the transport of oxygen throughout the body
• Neutrophils – the most common type of granulocytes and they serve as phagocytes
• Eosinophils – another type of granulocytes, which combat multicellular parasites
• Basophils – the least common type of granulocytes responsible for generating inflammatory responses
• Monocytes – give rise to macrophages and dendritic cells
• Platelets – responsible for blood clotting

Figure 1: Hematopoiesis

Furthermore, two common types of malignancies occur in the myeloid cells: acute myelogenous leukaemia (AML) and chronic myelogenous leukaemia (CML). Both AML and CML are cancers in the myeloid cells, characterized by the rapid growth of abnormal cells in the bone marrow.

What are Lymphoid Cells

Lymphoid cells are the other type of multipotent, hematopoietic progenitor cells that occur in the bone marrow. They also give rise to the T lymphocytes, B lymphocytes, and natural killer cells.

• T lymphocytes – play a key role in the cell-mediated immunity. Moreover, the three main types of T lymphocytes in the blood are the helper T cells, cytotoxic T cells, and regulatory T cells.
• B lymphocytes – play a key role in the humoral immunity by producing antibodies.
• Natural killer cells – involved in the innate immune system, providing a rapid response against viral-infected cells.

Figure 2: Formed Blood Cells

In addition, the two main types of malignancies in the lymphoid cells are acute lymphoblastic leukaemia (ALL) and chronic lymphocytic leukaemia (CLL). In fact, both are cancerous situations characterized by the production of a large number of immature lymphoblasts.

Similarities between Myeloid and Lymphoid Cells

• To begin with, myeloid and lymphoid cells are two types of multipotent, hematopoietic progenitor cells.
• Both of them occur in the bone marrow.
• Also, both differentiate from the hematopoietic stem cells.
• Furthermore, they are capable of differentiating into several types of functionally-related cells in a process known as hematopoiesis.
• Moreover, both give rise to the cells in the blood.
• Besides, they also give rise to dendritic cells.

Difference Between Myeloid and Lymphoid Cells

Definition

Myeloid cells refer to the large cells of the bone marrow that serve as a precursor of mainly the granulocytes and erythrocytes of the blood while lymphoid cells refer to any of the cells responsible for the production of immunity mediated by cells or antibodies and including lymphocytes, lymphoblasts, and plasma cells. Thus, this is the main difference between myeloid and lymphoid cells.

Types of Blood cells

Myeloid cells give rise to erythrocytes, neutrophils, basophils, eosinophils, monocytes, and platelets while lymphoid cells give rise to T lymphocytes, B lymphocytes, and natural killer cells. This is a significant difference between myeloid and lymphoid cells.

Related to

Another difference between myeloid and lymphoid cells is that the myeloid cells are related to bone marrow cells while the lymphoid cells are related to the lymphatic system.

Malignancies

AML and CML are the two main types of malignancies in the myeloid cells while ALL and the CLL are the two main types of malignancies in the lymphatic cells.

Conclusion

In summary, myeloid cells are a type of multipotent stem cells in the bone marrow and they give rise to the red blood cells granulocytes, monocytes, and platelets. On the other hand, lymphoid cells are the other type of multipotent cells in the bone marrow and they give rise to T and B lymphocytes and natural killer cells. Therefore, the main difference between myeloid and lymphoid cells is the type of blood cells they give rise to.

Reference:

1. “Lymphoid and myeloid lineage commitment in multipotent hematopoietic progenitors” Immunological reviews vol. 238,1 (2010): 37-46. Available Here

Image courtesy:

1. “Hematopoiesis simple” By Mikael Häggström, from original by A. Rad – Image:Hematopoiesis (human) diagram.png by A. Rad (CC BY-SA 3.0) via Commons Wikimedia  
2. “Blausen 0425 Formed Elements” By BruceBlaus. Blausen.com staff (2014). “Medical gallery of Blausen Medical 2014”. WikiJournal of Medicine 1 (2). DOI:10.15347/wjm/2014.010. ISSN 2002-4436. – Own work (CC BY 3.0) via Commons Wikimedia