Immunoregulation
Volume:5 Issue: 2, Winter 2022

Upon viral infection, the release of type I interferons (IFNs) plays a crucial role in limiting viral replication, reducing tissue damage, and boosting both innate and adaptive immune responses. A plasmacytoid dendritic cell (pDC) is a professional type I IFN-producing cell with the ability to produce large amounts of type I IFN quickly. However, when pDCs experience dysfunction or impairment in their ability to produce type I IFNs, the susceptibility to severe viral infections increases. Patients with severe COVID-19, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), exhibit lower levels of pDCs and diminished type I IFN responses compared to individuals with mild or asymptomatic disease. This association between severe COVID-19 and compromised IFN responses extends beyond underlying chronic illnesses. This review will also discuss the dysregulation of the pDC/type I IFN axis in COVID-19 and highlight the critical role of type I IFN-dependent factors contributing to the severity of COVID-19. Additionally, the impact of the IFN signature on a patient’s immune response to SARS-CoV-2 infection will be investigated.

Dysregulation of the immune system, as well as the endocrine, metabolic, and coagulation systems, has been linked to stress. The type of stressor (acute or chronic) may have a differential effect on immune function, with brief acute stress enhancing some parameters of immunity and chronic stress having a negative effect on many parameters of immune function. The hypothalamic-pituitary-adrenal axis and autonomic (sympathetic and parasympathetic) nervous systems mediate stress and immune functions. Exposure to frequent stressors can lead to repeated physiological arousal, failure to adapt to repeated stressors, failure to terminate the stress response after the stressor has ceased, and inadequate allostatic load to the stressor. The allostatic load provides an overall and body system-specific mechanistic relationship between stressor exposures and health outcomes that may explain minority health disparities. Multiple physiological systems interact at differing levels of activity in this condition. Principally, the severity of allostatic load is determined by using biomarkers of numerous body systems that depict physiological disturbances. There is a substantial connection between stress, immune function, inflammation, and coagulation. Consequently, immune/inflammatory/coagulation biomarkers may play crucial roles in the calculation of allostatic load, and the recommendation of additional biomarkers may improve the estimation accuracy of allostatic load.

Atopic march is defined as a natural progression of atopic manifestations characterized by a sequential development of allergic diseases in infancy. However, the atopic march does not always follow the typical sequence and the complete spectrum of atopic manifestations and may occur at any age. The aim of this study was to investigate the relationship between atopic march and the development of asthma versus the occurrence of asthma without a history of other allergies in the studied patients.  All patients with different types of allergy referred to the Asthma and Allergy Clinics of Azad University Hospitals from June 2021 to June 2022 were included in this case-control cross-sectional study. After the diagnosis by an allergist, the patients were asked to participate in a 5-minute interview to describe their allergy history. A total of 156 individuals with allergies were interviewed, of whom 94 patients had the asthma criteria. The mean age of the surveyed subjects was 32.03±13.35 years. The sample included 93 females (59.6%) and 63 males (40.4%). Asthma and atopic march were detected in 94(60.3%) and 12(7.7%) patients, respectively. Among the studied patients, 11.7% of the asthmatic patients had experienced atopic march throughout their lives. Classification of the patients based on the clinical phenotype of their disease, as well as the environmental triggers, can help create more targeted treatment to achieve better outcomes.

Sulfur mustard (SM), a chemical weapon used in the Iraq-Iran war from 1983-1988, has multiple chronic complications. This study aimed to evaluate one of the long-act effects of SM, i.e. the senescence according to the severity of injury in veterans via the estimation of biological health score (BHS) and relative telomere length (TL) of immune cells. 

SM-chemical veterans were categorized into three groups according to the percentage of chemical injury (5-20%, 25-45%, and 50-70%). Healthy volunteers also participated as a control group. Eighteen biomarkers from different physiological systems (inflammatory/immune, endocrine, cardiovascular, and metabolic), and organs (liver and kidney) were used to estimate BHS. The TL of immune cells was also measured for each participant by monochrome multiplex real-time PCR. 

There were significant correlations between age-adjusted TL (negative), BHS, and BHS/TL ratio (positive) and the percentage of injury. The TL was significantly decreased in all veterans with different injuries compared to healthy participants while it did not change in veterans with the injury percentages of 25-45% and 50-70%. The BHS in three groups of veterans was significantly higher than in healthy individuals. The BHS/TL ratio was significantly changed between all groups and increased with the progress of injury. 

The BHS and TL may not individually be accurate indices for the determination of senescence and biological aging while the ratio of these two parameters improves this defect and could be a more reliable index indicating biological aging in chemical veterans with different percentages of injury.

COVID-19 is the most common cause of increased levels of cortisol and interleukin 6 (IL-6). The purpose of this pilot study was to examine the effect of home-based resistance training on the serum levels of IL-6 and cortisol in recovered women with COVID-19. A pilot randomized controlled design was used. Twenty middle-aged women who recovered from COVID-19 were assigned randomly to the intervention and control groups. The height, weight, and body mass index (BMI) of all participants were measured both before and after the intervention period. Blood samples were taken in the morning to determine the serum levels of IL-6 and cortisol. Fitness (estimated VO2 max) was assessed with a 1.6-km walking test. The intervention group followed eight weeks, three days per week, 1 hour per day of thera-band resistance training and body weight training at home. The control group did not participate in any sports program.  At baseline, there were no significant differences between both groups in the mean IL-6, and cortisol levels (P>0.05). After the intervention, the mean IL-6 and cortisol levels significantly decreased in the intervention group (P<0.05). Eight weeks of thera-band resistance band training program and bodyweight workout decreases the serum levels of cortisol and IL-6 and improves the immune system of recovered women with COVID-19. Additionally, there seem to be some indications that this training might have a positive influence on immune function. Further research in this area is highly recommended.

Clays and clay minerals have great potential for exerting positive impacts on human health and implementation in medical applications. They are industrial minerals used in various medical applications, like drug delivery. Considering the abundance of clay resources in Iran, we decided to investigate the role of natural clays in peripheral blood mononuclear cells (PBMCs), as effective immune system cells that provide the health of the body in disease and standard times. Investigating the cytotoxicity of these minerals on PBMCs helps to understand their performance in medicine and the treatment of patients.

The studied clays, including bentonite, zeolite, and sepiolite, were prepared from Iran mines, and their characterizations were scanned by x-ray fluorescence (XRF), x-ray diffraction, and cation-exchange capacity (CEC) determination. PBMCs were isolated by Ficoll-Hypaque density gradient centrifugation, and 200000 PBMC cells were exposed to different concentrations of clays (1-1000 µg/mL) for 48 h in 96-well cell culture plates. Cell cytotoxicity response was determined using 3-[4, 5-dimethylthiazole-2-yl]-2, 5-diphenyltetrazolium bromide (MTT) assay.

Bentonite inhibited cell proliferation after 48 h of incubation at a concentration above 0.05 mg/mL, whereas zeolite inhibited cell proliferation at 10 and 5 mg/mL. Sepiolite does not have any cytotoxic effect at all of the concentrations. CEC for bentonite, zeolite, and sepiolite were 86 cmol(+)/kg, 15.5 cmol(+)/kg, and 3.54 cmol(+)/kg, respectively, and showed a direct relationship with cell growth. 

The cytotoxicity of the investigated clays is less than those reported in the literature review. This suggests that the studied clays with beneficial properties have great potential to be used in medicine, taking into account the size, type, and concentration of clays. In vivo and long-term studies on bio-culture and biodistribution are essential to understand better the role of the studied clays. Furthermore, our results could provide a new perspective on the safety of using cheap and naturally available clays in medical and industrial applications.

Bacterin-based vaccination may be a stressful condition, leading to harmful effects, such as high lipid peroxidation and telomere shortening. This study aimed to reduce these probable side effects via the administration of different concentrations of licorice (because of its anti-oxidative and anti-aging properties).

Japanese quails as animal models were reared for 42 days under standard conditions. The birds were divided into eight groups, including a control group, licorice treatments (licorice 0.02%, Licorice 0.04%, and licorice 0.08% groups), and Salmonella bacterin treatments (bacterin, bacterin+licorice 0.02%, bacterin+licorice 0.04%, and bacterin+licorice 0.08% groups). The Salmonella enterica bacterin-based vaccine was injected twice on days 14 and 28. Serum lipid peroxidation and telomere length of immune cells in all experimental groups were measured. 

Lipid peroxidation and telomere shortening enhanced following bacterin vaccination. Licorice at doses of 0.04%, 0.08%, or both reduced the lipid peroxidation and telomere shortening in non-vaccinated and vaccinated birds, while the dose of 0.02% was not effective.

This study confirmed the side effects of high lipid peroxidation and telomere attrition for S. enterica bacterin-based vaccination. Also, the improving properties of licorice for these side effects were considered to be effective.