Autumn Epidemic

17.01.2024

COVID Impacts: Immune Dysfunction

Source: Memorial Sloan Kettering Cancer Center Library / LibGuides / COVID Impacts / Immune Dysfunction

Detailed information and resources on the long-term health consequences of COVID-19 infection and the broad social impacts of the COVID-19 pandemic.

One of the most concerning long-term effects of COVID-19 is the dysregulation and dysfunction of the immune system.
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Memorial Sloan Kettering Library

COVID Impacts: Immune Dysfunction

Szczegółowe informacje i zasoby na temat długoterminowych konsekwencji zdrowotnych zakażenia COVID-19 oraz szerokich skutków społecznych pandemii COVID-19.

One of the most concerning long-term impacts of COVID-19 is immune dysregulation and dysfunction. Immune system impacts were heavily documented, even in the first waves of the pandemic, however there was a lack of understanding as to what exactly COVID-19 infections were doing to the immune system, and what that might mean both during acute infection and long-term.

 
Early Hypotheses

Early on in the pandemic, there were two main hypotheses for the pathophysiology of COVID-19 severe disease and death: hyperactive immune system and immune system failure.

 
Hyperactive Immune System

The first was due to an overactive immune system. Early on it was noted that many patients with severe COVID-19 ended up developing ARDS (acute respiratory distress syndrome). This was reminiscent of the cytokine release syndrome (CRS) - induced ARDS and secondary hemophagocytic lymphohistiocytosis (sHLH) that had been observed previously in patients with SARS-CoV and MERS-CoV (it also is a common adverse event in cancer patients treated with CAR-T cell therapies).

Therefore it lead researchers to believe that severe infections were the results of an overactive immune response caused by excessive inflammatory cytokines, which lead to inflammatory lung and vascular injuries, and that death was from subsequent respiratory failure or coagulopathy.

 
Immune System Failure

The second hypothesis took the exact opposite hypothesis, that COVID-19 caused immune collapse. In this hypothesis, COVID-19 causes the patient's protective immunity to collapse, causing uncontrolled viral replication and dissemination which lead to cytotoxicity and death. Support for this contrasting theory was based on the observed progressive and profound lymphopenia, often to levels seen in patients with AIDS.

More recent research has concluded that COVID-19 causes dysregulation to both the innate and the adaptive immune systems. Paradoxically, in COVID-19 pneumonia, the innate immune system fails to mount an effective antiviral response while also inducing potentially damaging inflammation.

COVID-19 Alters Both Innate and Adaptive Immunity

The immune system is made up of two parts: the innate, (general) immune system and the adaptive (specialized) immune system. These two systems work closely together and take on different tasks.

 
Innate Immunity

Responsible for the initial immune response and antiviral activity, the innate system functions as a single defense mechanism, crucial for host response and illness protection.

Severe COVID cases were found to have decreased production of early immune responses (INF) which in turn lead to the virus replicating and causing severe cellular lung damage. Not only is was the antiviral response of IFN delayed and reduced, but it was also accompanied an overexaggerated inflammatory response with excessive cytokines. This resulting hyperinflammation caused edema, fibrosis, and thromboses in the lungs that ultimately lead to hypoxia, acute respiratory distress syndrome (ARDS) and death.

 
Adaptive Immunity

The adaptive immune system is critical for the development of efficient host responses to invading pathogens as well as immunological memory for future infections of similar pathogens.

Although COVID-19 patients may exhibit elevated levels of inflammatory cytokines compared to non-critically-ill patients, a study comparing the immune profiles of COVID-19 and influenza noted that while a 3–4% subset of COVID-19 patients exhibited hyperinflammation characteristic of a cytokine storm, they more commonly demonstrated immunosuppression.

CD4+ helper T cells and CD8+ cytotoxic T cells have been identified as crucial in the immunologic response to SARS-CoV-2 infection. CD4+ T cells are responsive to the virus's spike protein, and the presence of CD8+ T cell expansion in bronchoalveolar lavage is correlated with illness moderation. However, one of the most remarkable characteristics of immune dysregulation in COVID-19 is an immense depletion of CD4+ and CD8+ T cells associated with disease severity.

While lymphopenia is observed in other respiratory viral illnesses such as influenza A H3N2 viral infection, COVID-19 induced lymphocytic depletion is distinctive for its magnitude and longevity. Additionally, CD8+ T cells, crucial for their cytotoxic activity against virally infected cells, may experience the more stark reduction.

The lack of intense lymphocytic infiltration found in the lungs of critical COVID-19 patients demonstrates that the peripherally observed lymphopenia may be occurring through a mechanism beyond simply recruitment to the infection site.

Cases of children presenting to emergency departments for asthma exacerbations in major Canadian cities were reviewed during 3 weeks of September 2001. Microbiology of the nasal mucosa using PCR* was used with specific identification of human rhinoviruses, adenoviruses, influenza A and B viruses, parainfluenza 1 to 3, coronaviruses 229E and OC43, RS A and B viruses and Chlamydia pneumoniae and Mycoplasma pneumoniae. The results are shown in the figure above.

* PCR ang. polymerase chain reaction technique – it is the most sensitive diagnostic microbiological test that allows the detection of DNA or RNA of a virus, bacteria or other organism. This highly sensitive analytical method uses advanced molecular biology techniques.

WHY DOES BACK TO SCHOOL CONTRIBUTE TO THE EPIDEMIC?

Children who return to school after the summer holidays are at risk of viral infections, most commonly rhinoviruses, after they have not been exposed to them for many weeks. Late summer is a time of high levels of environmental allergens and they are common in the school environment. Back to school is also a time of high stress, which can worsen asthma symptoms in children. Viral infection is a direct trigger of asthma exacerbations, it is probably the combination of all these factors that is the cause of the September epidemic.

The seasonality of rhinovirus infections at the end of summer and beginning of autumn must have some variability over time. One should therefore expect some volatility during the September epidemics. However, the peak in the number of hospitalizations in the 13 years of observation of the authors invariably occurred within 3 weeks of starting school, suggesting that starting school is per se a necessary condition for accelerating the transmission of rhinovirus infections to the epidemic level. This hypothesis is supported by data from those countries where school starts on a different date. For most children in Canada and England, school usually starts after the summer break on September 1. In Scotland and Sweden, school usually starts in the 3rd week of August. The greatest peak in hospital admissions for an asthma exacerbation in all these 4 countries occurs exactly 3 weeks after returning to school, regardless of the variation in the timing of summer holidays, as graphically depicted in the figure below.

Figure: Number of hospitalizations, presented as a multiple of the average, broken down by individual weeks during the year, in selected countries.

HOW CAN WE PROTECT OUR CHILDREN?

Phytomedica offers a proven preparation that strengthens the immunity of both children and adolescents as well as adults. It is Immulina in the form of a tasty syrup for small children or people who have trouble swallowing capsules and in the form of capsules for adolescents and adults.

Figure: Consumption of preparations providing a special extract of Spirulina platensis within a few days triggers various mechanisms of non-specific immunity.

Studies have confirmed that the active ingredient of both preparations - a special extract of Spirulina platensis (LECPEEN) activates the mechanisms of innate immunity. Immunity that does not threaten to trigger chronic immune processes. The improvement of immunity occurs quickly, because within a few days (4 - 5 days) from the start of the treatment. This is manifested by an increase in the production of protective antibodies for the mucous membranes (IgA), an increase in the production of proteins (cytokines, especially IL-6) involved in the immune processes and stimulates a number of other substances (lymphokines, IFN-γ) and stimulates the cells of the immune system (m among others NK lymphocytes).

Conclusion:
it is worth strengthening children's immunity from the beginning of September!

REFERENCES

Structure of the Immune System

The immune system is a very complex structure consisting of cells, tissues and organs that work together to protect (defend) our body against "foreign" invaders . . .

How the Immune System Works?

It is one of nature's most fascinating inventions. It easily protects us against billions of bacteria, viruses and pathogens. We don't realize that the immune system . . .

Immunodeficiencies

Immunodeficiencies are disorders of the immune system that are characterized by a reduced or lack of ability to . . .

Maintain Healthy Immune System

If we are not dealing with an immune system disease, it is usually enough to use a few simple . . .

News

The European Medicines Agency (EMA) has approved gene therapy for the treatment of severe combined immunodeficiency due to adesine deaminase deficiency (ADA-SCID), which is the result of a genetic mutation - reports New Scientist. You can read about gene therapy, what it is and its prospects, on the website News Medical Life Sciencies

17.01.2024
COVID Impacts: Immune Dysfunction

Source: Memorial Sloan Kettering Cancer Center Library / LibGuides / COVID Impacts / Immune Dysfunction

Detailed information and resources on the long-term health consequences of COVID-19 infection and the broad social impacts of the COVID-19 pandemic.

One of the most concerning long-term effects of COVID-19 is the dysregulation and dysfunction of the immune system.

08.08.2023
Immunomodulating Effects of Fungal Beta-Glucans: From Traditional Use to Medicine

Source: Nutrients Authors: van Steenwijk H, Bast, A and de Boer A.

Beta-glucans derived from mushrooms are bioactive long-chain polysaccharide compounds, insoluble in water and with immunomodulatory properties. Knowledge of the action and functions of beta-glucans, which have been used in traditional medicine for centuries, is developing thanks to modern immunological and biotechnological methods.

04.08.2023
Spirulina Lipopolysaccharides Inhibit Tumor Growth

Source: Oncology Reports; Authors: Hiromi Okuyama Akira Tominaga, z Laboratory of Immunology, Faculty of Pharmacy, Osaka Ohtani University, Tondabayashi, Osaka 584-8540, Japan

Spirulina lipopolysaccharides inhibit tumor growth in a Toll-like receptor 4-dependent manner by altering the cytokine milieu from interleukin-17/interleukin-23 to interferon-γ