Cytokines are small soluble proteins that are secreted by immune cells and tissue cells to play a regulatory role between cells, including interferon (IFN), interleukin (IL), chemokines, colony-stimulating factors (CSF), tumor necrosis factors (TNF) and so on. Cytokines function in autocrine, paracrine or endocrine forms, and can regulate cell growth and differentiation, modulate immune response and participate in the development of various diseases such as inflammation by binding to the corresponding receptors.
Cytokine storm is also known as cytokine waterfall cascade, or hypercytokinaemia. Cytokine storm was first proposed by Ferrara et al. in 1993 while studying graft-versus-host disease. When the body’s immune system is affected by infectious (bacterial, viral, fungal, etc.) or non-infectious (drugs, autoimmune diseases, etc.) factors, the body sequentially initiates a non-specific immune response and a specific immune response. Various immune cells in the body such as macrophages, neutrophils, natural killer cells and dendritic cells can release various cytokines, such as IL-1, IL-2, IL-6, IL-8, IL-10, IL-12, chemokines, granulocyte colony-stimulating factor, granulocyte megakaryocyte colony-stimulating factor, IFN-γ, TNF-α and so on. Through a specific positive feedback mechanism between these cytokines and neutrophils, macrophages and various immune cells, multiple cytokines and related immune cells abnormally increase and accumulate in tissues and organs, forming a cytokine storm, which eventually leads to single or multiple organ damage or even functional failure.
A variety of viruses such as SARS-CoV, influenza A (H1N1) virus, and MERS-CoV can cause cytokine storms after infection of humans. However, the cytokine profiles that play a major role in cytokine storms due to different coronavirus infections may be different. For example, the cytokine storm associated with SARS virus is mainly associated with IL-6, IL-8, IL-12, IFN-γ, interferon-γ-induced protein 10, and monocyte chemotactic protein 1. The cytokine storm caused by MERS-CoV is mainly associated with IFN-γ, TNF-α, IL-15, IL-17, etc.
SARS-CoV-2 can attack the body at multiple targets, creating a cytokine storm that causes single or multiple organ dysfunction.
The process of SARS-CoV-2 invasion of the body begins with cytokines produced as a result of viral infection promoting an inflammatory response and recruitment of immune cells to the lungs. Subsequently, cytokines occur that lead to lymphatic system dysfunction, allowing impaired clearance and increased virus replication and dissemination. Eventually, an immune cascade amplifies the effect, producing a cytokine storm that aggravates alveolar wall and capillary leakage, filling the alveoli with necrotic cells and secretions, blocking the capillaries in the alveolar wall, and the formation of hyaline membranes.
Luminex multiplex assay technology is particularly suitable for cytokine storm detection. It has the following advantages:
1. Multiplex detection: simultaneous detection of 100 biological targets
2. High sensitivity: accurate quantification down to 0.1pg/mL
3. Saving sample: only a sample volume as low as 25μL is required
4. Saving time: the experiment process only takes 4 hours
5. Can be widely used in clinical and multidisciplinary research fields
