Evaluating the role of chemokines and chemokine receptors involved in coronavirus infection

Author(s):  
Gema Olivarria ◽  
Thomas E. Lane
Mathematics ◽  
2021 ◽  
Vol 9 (11) ◽  
pp. 1221
Author(s):  
Giorgio Sonnino ◽  
Fernando Mora ◽  
Pasquale Nardone

We propose two stochastic models for the Coronavirus pandemic. The statistical properties of the models, in particular the correlation functions and the probability density functions, were duly computed. Our models take into account the adoption of lockdown measures as well as the crucial role of hospitals and health care institutes. To accomplish this work we adopt a kinetic-type reaction approach where the modelling of the lockdown measures is obtained by introducing a new mathematical basis and the intensity of the stochastic noise is derived by statistical mechanics. We analysed two scenarios: the stochastic SIS-model (Susceptible ⇒ Infectious ⇒ Susceptible) and the stochastic SIS-model integrated with the action of the hospitals; both models take into account the lockdown measures. We show that, for the case of the stochastic SIS-model, once the lockdown measures are removed, the Coronavirus infection will start growing again. However, the combined contributions of lockdown measures with the action of hospitals and health institutes is able to contain and even to dampen the spread of the SARS-CoV-2 epidemic. This result may be used during a period of time when the massive distribution of vaccines in a given population is not yet feasible. We analysed data for USA and France. In the case of USA, we analysed the following situations: USA is subjected to the first wave of infection by Coronavirus and USA is in the second wave of SARS-CoV-2 infection. The agreement between theoretical predictions and real data confirms the validity of our approach.


2011 ◽  
Vol 2011 ◽  
pp. 1-12 ◽  
Author(s):  
Linda Hammerich ◽  
Felix Heymann ◽  
Frank Tacke

Unbalanced Th1/Th2 T-cell responses in the liver are a characteristic of hepatic inflammation and subsequent liver fibrosis. The recently discovered Th17 cells, a subtype of CD4+T-helper cells mainly producing IL-17 and IL-22, have initially been linked to host defense against infections and to autoimmunity. Their preferred differentiation upon TGFβand IL-6, two cytokines abundantly present in injured liver, makes a contribution of Th17 cells to hepatic inflammation very likely. Indeed, initial studies in humans revealed activated Th17 cells and Th17-related cytokines in various liver diseases. However, functional experiments in mouse models are not fully conclusive at present, and the pathogenic contribution of Th17 cells to liver inflammation might vary upon the disease etiology, for example, between infectious and autoimmune disorders. Understanding the chemokines and chemokine receptors promoting hepatic Th17 cell recruitment (possibly CCR6 or CCR4) might reveal new therapeutic targets interfering with Th17 migration or differentiation in liver disease.


2021 ◽  
Vol 21 (3) ◽  
pp. 159-164
Author(s):  
Tamara N. Shvedova ◽  
Olga S. Kopteva ◽  
Polina A. Kudar ◽  
Anna A. Lerner ◽  
Yuliya A. Desheva

BACKGROUND: Despite the continuing global spread of the coronavirus infection COVID-19 caused by the SARS-CoV-2 coronavirus, the mechanisms of the pathogenesis of severe infections remain poorly understood. The role of comorbidity with other seasonal viral infections, including influenza, in the pathogenesis of the severe course of COVID-19 remains unclear. MATERIALS AND METHODS: The present study used sera left over from ongoing laboratory studies of patients with varying degrees of severity of COVID-19. The study was approved by the Local Ethics Committee of the Federal State Budgetary Scientific Institution IEM (protocol 3/20 from 06/05/2020). We studied 28 paired samples obtained upon admission of patients to the hospital and after 57 days of hospital stay. Paired sera of patients with COVID-19 were tested for antibodies to influenza A and B viruses. The presence of IgG antibodies specific to the SARS-CoV-2 spike (S) protein was studied using an enzyme-linked immunosorbent assay (ELISA). The serum concentration of C-reactive protein and the neutrophil-lymphocyte ratio on the day of hospitalization were also assessed. RESULTS: At least a 4-fold increase in serum IgG antibodies to SARS-CoV-2 S protein was found both in patients with PCR-confirmed SARS-CoV-2 infection and without PCR confirmation. It was shown that out of 18 patients with moderate and severe forms of COVID-19 infection, six of them showed at least a 4-fold increase in antibodies to influenza A/H1N1, in one to influenza A/H3N2 and in two cases to the influenza B. Laboratory data in these two groups were characterized by significant increases in serum C-reactive protein and neutrophil-lymphocyte ratio concentrations compared with the moderate COVID-19 group. CONCLUSIONS: Serological diagnostics can additionally detect cases of coronavirus infection when the virus was not detected by PCR. In moderate and severe cases of COVID-19, coinfections with influenza A and B viruses have been identified. The results obtained confirm the need for anti-influenza immunization during the SARS-CoV-2 pandemic. Influenza virus screening can significantly improve patient management because recommended antiviral drugs (neuraminidase inhibitors) are available.


Author(s):  
Leonid Anatolievich Denisov ◽  
Mikhail Sergeevich Pakhomov

The article is devoted to a historical event that occurred 250 years ago in Moscow. The authors draw analogies between the plague epidemic and the current situation associated with a new coronavirus infection, and note what unites these events. It shows the dedicated work of doctors in the conditions of complete ambiguity of the causes and spread of these infections, in the absence of effective treatment methods, what was the behavior of the population, how prevention measures were developed, and what is the role of the authorities of Moscow and St. Petersburg in the fight. How the state of medical science and the level of health care, referred to by economists as the non — material sphere, can affect the physical and mental health of the population and the economic situation of the city, country and the whole World.


Author(s):  
Tiziana Schioppa ◽  
Francesca Sozio ◽  
Ilaria Barbazza ◽  
Sara Scutera ◽  
Daniela Bosisio ◽  
...  

CCRL2 is a seven-transmembrane domain receptor that belongs to the chemokine receptor family. At difference from other members of this family, CCRL2 does not promote chemotaxis and shares structural features with atypical chemokine receptors (ACKRs). However, CCRL2 also differs from ACKRs since it does not bind chemokines and is devoid of scavenging functions. The only commonly recognized CCRL2 ligand is chemerin, a non-chemokine chemotactic protein. CCRL2 is expressed both by leukocytes and non-hematopoietic cells. The genetic ablation of CCRL2 has been instrumental to elucidate the role of this receptor as positive or negative regulator of inflammation. CCRL2 modulates leukocyte migration by two main mechanisms. First, when CCRL2 is expressed by barrier cells, such endothelial, and epithelial cells, it acts as a presenting molecule, contributing to the formation of a non-soluble chemotactic gradient for leukocytes expressing CMKLR1, the functional chemerin receptor. This mechanism was shown to be crucial in the induction of NK cell-dependent immune surveillance in lung cancer progression and metastasis. Second, by forming heterocomplexes with other chemokine receptors. For instance, CCRL2/CXCR2 heterodimers were shown to regulate the activation of β2-integrins in mouse neutrophils. This mini-review summarizes the current understanding of CCRL2 biology, based on experimental evidence obtained by the genetic deletion of this receptor in in vivo experimental models. Further studies are required to highlight the complex functional role of CCRL2 in different organs and pathological conditions.


Molecules ◽  
2021 ◽  
Vol 26 (17) ◽  
pp. 5174
Author(s):  
Santosh R. Alluri ◽  
Yusuke Higashi ◽  
Kun-Eek Kil

Chemokines and chemokine receptors have been recognized as critical signal components that maintain the physiological functions of various cells, particularly the immune cells. The signals of chemokines/chemokine receptors guide various leukocytes to respond to inflammatory reactions and infectious agents. Many chemokine receptors play supportive roles in the differentiation, proliferation, angiogenesis, and metastasis of diverse tumor cells. In addition, the signaling functions of a few chemokine receptors are associated with cardiac, pulmonary, and brain disorders. Over the years, numerous promising molecules ranging from small molecules to short peptides and antibodies have been developed to study the role of chemokine receptors in healthy states and diseased states. These drug-like candidates are in turn exploited as radiolabeled probes for the imaging of chemokine receptors using noninvasive in vivo imaging, such as positron emission tomography (PET). Recent advances in the development of radiotracers for various chemokine receptors, particularly of CXCR4, CCR2, and CCR5, shed new light on chemokine-related cancer and cardiovascular research and the subsequent drug development. Here, we present the recent progress in PET radiotracer development for imaging of various chemokine receptors.


2021 ◽  
Vol 40 (4) ◽  
pp. 33-42
Author(s):  
Igor V. Litvinenko ◽  
Miroslav M. Odinak ◽  
Nikolay V. Tsygan ◽  
Aleksander V. Ryabtsev

The central nervous system seems to be quite vulnerable to SARS-CoV-2, leading to a variety of alteration pathways, high incidence and variability of the neurological symptoms of COVID-19. The COVID-19 symptoms, possibly associated with alteration to the central nervous system, include hyperthermia, shortness of breath, fatigue, headache, dizziness, dysphonia, dysphagia, hyposmia and anosmia, hypogeusia and ageusia, impairment of consciousness. The impairment of olfaction and gustation are the most common symptoms of the nervous system alteration (98% and 70%, respectively), which is most likely a consequence of the alteration of the receptors. Presumably the pathogenesis of dysphonia and dysphagia may involve neurodegenerative mechanisms or may be associated with a predominantly demyelinating alteration of the caudal cranial nerves. Pathomorphological findings in the brain of the COVID-19 patients include diffuse hypoxic and focal ischemic injuries of various sizes up to ischemic infarctions (in thrombosis of large arteries); microangiopathy; vasculitis; diapedetic and confluent hemorrhages with possible progression to hemorrhagic infarctions and rarely intracerebral hematomas. Acute cerebrovascular accident worsens the course of COVID-19 and can worsen the clinical outcome, taking into account the mechanisms of the central nervous system alteration in highly contagious coronavirus infections (SARS-CoV, MERS, SARS-CoV-2), including embolism, hypoxia, neurodegeneration, systemic inflammatory response and immune-mediated alteartion to the nervous tissue. A fairly rare complication of coronavirus infection, however, acute myelitis requires attention due to the severity of neurological disorders. The literature data show high incidence and polymorphism of the symptoms of the central nervous system alteration, as well as the important role of the cerebrovascular and neurodegenerative pathogenesis of brain alteration in COVID-19, which is taken into account in examining and treating the patients with new coronavirus infection. (1 figure, bibliography: 61 refs)


Sign in / Sign up

Export Citation Format

Share Document