Difference Between Cytokines and Chemokines (With Table)

If someone is studying in the field of medical and especially cellular biology. Then it is obvious to come across two of the terms, namely cytokines and chemokines. The role played by them is unique as argument natural defenses of the body.  

The human body is designed in such a way that it can combat a range of diseases that mainly involve foreign organisms like bacteria. In terms of the immune system, both terms are connected and create confusion. In this article, the difference between cytokines and chemokines is highlighted. 

Cytokines vs Chemokines 

The main difference between the cytokines and the chemokines is that cytokines are small proteins produced by immune cells dominantly, which are vital in cell signaling. On the other hand, chemokines are specific cytokines that are particularly adapted for cells chemotaxis. 

Cytokines are inflammatory molecules and by cells secreted as small proteins. Initially, they are produced by particular macrophages and T Helper cells. To a specific receptor they and initiate a reactions cascade to trigger an immune response. They also behave like hormones. 

A chemokine is a diverse group of different kinds of protein molecules. Their protein particles have low molecular weight. Its chief function is leukocytes activation and to the target site, they facilitate migration. The two different types of chemokines are homeostatic and inflammatory chemokines. 

Comparison Table Between Cytokines and Chemokines 

Parameters of Comparison

Cytokines

Chemokines

Interpretation

By immune cells, these small proteins are produced dominantly which are vital in cell signaling.

It is a specific cytokine that is particularly adapted for cells chemotaxis.

Size

~5-20 kDa

~8-10 kDa

Affect

Several cells in the body

Mainly lymphocytes and leukocytes

Conserved cysteine residues

Present

Absent

Examples

IFN-γ, IFN-a, TNFα, IL-1,6,12, etc.

CXCR1-7, CCL15, CCL21, CCL1, XCL1, etc.

What are Cytokines?  

Cytokines are a loose and broad category of small proteins which are vital in the signaling of the cell. They are peptides and fail to cross the cell’s lipid bilayer to enter the cytoplasm. Cytokines are involved in paracrine, endocrine, and autocrine signaling as agents of immunomodulation.  

It serves as a role of regulation in the immune system. The following healing process and infection resolution are mediated by cytokines. It generally consists of lymphokines, interleukins, interferons, and tumor necrosis factors, but not growth factors or hormones. They are produced by a range of cells such as mast cells, macrophages, T lymphocytes, and B lymphocytes.  

Cytokines act through receptors of cell surface and are especially vital in the immune system. They modulate the balance between cell-based and humoral immune responses. They regulate the growth, responsiveness, and maturation of specific cell populations.  

Several cytokines inhibit or enhance the action of some other cytokines in complex ways. From cells they are different, which are also vital molecules for cell signaling. They are vital diseases and health, like cancer, trauma, inflammation, sepsis, and reproduction. 

What are Chemokines?  

Chemotactic cytokines, or in simple words chemokines are small cytokines families of signaling proteins that are secreted by cells that induce leukocytes’ directional movement. They are vital for biological processes consisting of wound healing and morphogenesis as well as disease pathogenesis.  

According to structural and behavior characteristics, cytokine proteins are divided into chemokines. Apart from being mediating chemotaxis, chemokines are in mass approximately 8-10 kilodaltons and have cysteine residues mainly four in number in a conserved location that is the basis to form their 3D shape.  

Chemokine’s chief role is to act as a chemoattractant for guiding cells migration. Cells that are attracted through chemokines follow a signal of chemokine concentration increasing towards the chemokine source. During the process of immune surveillance, some chemokines control the immune system’s cells.  

When it comes to the role in development, some chemokines promote angiogenesis or simply guide cells to tissue and provide critical specific signals for the maturation of cells. Others are inflammatory, and from a range of cells, they are released in response to viruses, bacterial infections, and physical damage causing agents like urate crystals or silica. 

Main Differences Between Cytokines and Chemokines 

  1. When it comes to chemical messengers, cytokines are a broad family of this kind of messengers which serves to bring about the response related to immune. On the other hand, chemokines are just chemotactic cytokines.  
  2. The function of cytokines is to help in molecule signaling that mediates and regulates immunity hematopoiesis and inflammation. Meanwhile, the function of chemokines is to direct the white blood cells’ migration to damaged or infected tissues.  
  3. In terms of importance, cytokine serves as a role of regulation in the immune system. The following healing process and infection resolution are mediated by cytokines. Conversely, the importance of chemokines is to ensure that infection fails to spread from the origin of detection.  
  4. Cytokines can be classified into interleukins, chemokines, lymphokines, interferon, and tumor necrosis factor. On the flip side, chemokines can be classified into mainly four subfamilies such as XC, CC, CXC, CX3C.  
  5. The involvement of cytokinesis in both cells mediated as well as humoral immunity. In contrast, chemokines are only involved in the immune system’s directing cells to a target site. 

Conclusion 

It can be concluded that both cytokine and chemokine terms are obvious to come across while studying in the field of cellular biology. The role played by them is unique as argument natural defenses of the body. Several cells are affected by cytokines in the body. Conversely, mainly lymphocytes and leukocytes are affected by chemokines.  

Cytokines are small proteins produced dominantly by immune cells, which are vital in cell signaling. Meanwhile, chemokines are specific cytokines that are particularly adapted for cells chemotaxis. Conserved cysteine residues are present in cytokines, whereas they are absent in chemokines. Examples of cytokines are IFN-γ, IFN-a, TNFα, IL-1,6,12, etc. In contrast, CXCR1-7, CCL15, CCL21, CCL1, and XCL1 are a few examples of chemokines. 

References  

  1. https://www.sciencedirect.com/science/article/pii/S001236921551814X
  2. https://ashpublications.org/blood/article-abstract/90/3/909/237107