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3.
Cytokine ; 165: 156163, 2023 05.
Artigo em Inglês | MEDLINE | ID: covidwho-2244397

RESUMO

PURPOSE OF THE RESEARCH: We proposed T-cell lymphocytopenia as a strategic predictor of serious coronavirus and influenza infections. Our preeminent goal was to determine whether a degree of T-cell lymphopenia would identify a distinct threshold cell count to differentiate between severe and non-severe infections. We codified an Index Severity Score to exploit an association between T-cell cytopenia and the grade of disease activity. PRINCIPAL RESULT: A T-cell count of 560 cells/uL or below signified a trend towards advanced disease.


Assuntos
Influenza Humana , Linfopenia , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave , Humanos , Linfócitos T , Linfopenia/complicações , Morbidade
4.
Transfus Apher Sci ; 62(1): 103625, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: covidwho-2227466

RESUMO

The latest WHO report determined the increasing diversity within the CoV-2 omicron and its descendent lineages. Some heavily mutated offshoots of BA.5 and BA.2, such as BA.4.6, BF.7, BQ.1.1, and BA.2.75, are responsible for about 20% of infections and are spreading rapidly in multiple countries. It is a sign that Omicron subvariants are now developing a capacity to be more immune escaping and may contribute to a new wave of COVID-19. Covid-19 infections often induce many alterations in human physiological defense and the natural control systems, with exacerbated activation of the inflammatory and homeostatic response, as for any infectious diseases. Severe activation of the early phase of hemostatic components, often occurs, leading to thrombotic complications and often contributing to a lethal outcome selectively in certain populations. Development of autoimmune complications increases the disease burden and lowers its prognosis. While the true mechanism still remains unclear, it is believed to mainly be related to the host autoimmune responses as demonstrated, only in some patients suffering from the presence of autoantibodies that worsens the disease evolution. In fact in some studies the development of autoantibodies to angiotensin converting enzyme 2 (ACE2) was identified, and in other studies autoantibodies, thought to be targeting interferon or binding to annexin A1, or autoantibodies to phospholipids were seen. Moreover, the occurrence of autoimmune heparin induced thrombocytopenia has also been described in infected patients treated with heparin for controlling thrombogenicity. This commentary focuses on the presence of various autoantibodies reported so far in Covid-19 diseases, exploring their association with the disease course and the durability of some related symptoms. Attempts are also made to further analyze the potential mechanism of actions and link the presence of antibodies with pathological complications.


Assuntos
COVID-19 , Hemostáticos , Humanos , COVID-19/complicações , Síndrome , Autoanticorpos , Progressão da Doença
7.
Transfus Apher Sci ; 61(6): 103499, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: covidwho-1915045

RESUMO

Although mass vaccination combined with some other preventative strategies and lockdown was associated with some early signs that COVID-19 infection might be fading away, the over 35 sites mutated new South African variant, "Omicron", emerged almost globally. Certain predisposed hosts may develop severe inflammatory thrombotic or mild long-Covid conditions due to this variant, which depletes T-cells, neutralizes antibodies circulating in the body, and coincidentally induces hypercoagulability. The surge of Omicron combined with Delta variants may confer unresponsiveness to the currently available vaccines even when the second dose is given up to 90 days. A drop in the antibody levels by 30 % has been identified in omicron-infected individuals, and one in five people is resistant to antibody treatment. This poses major concerns in the transmissibility rate of this new variant, even in a heavy mass vaccinated environment. This heavily mutated Omicron with other spike sites facilitates viral entry into the cells through conformational changes, irrespective of circulating neutralising antibody. Based on this consideration, we believe that speeding up mixed-matched vaccines with higher T-cell stimulation ability may improve the current situation. Moreover, large orders for antiviral drugs and monoclonal antibodies that could tackle Omicron combined with other variants may be valuable. The use of free polyclonal antibody donations and, hopefully, T-cell immunotherapy, may represent further breakthrough therapeutic interventions. However, Omicron infection is relatively milder than the ongoing Delta variant but is extremely contagious, and therefore the development of novel interventions is highly demanding.


Assuntos
COVID-19 , Vacinas , Humanos , COVID-19/prevenção & controle , Controle de Doenças Transmissíveis , SARS-CoV-2 , Anticorpos Monoclonais , Síndrome de COVID-19 Pós-Aguda
9.
Transfus Apher Sci ; 61(4): 103488, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: covidwho-1886109

RESUMO

The COVID-19 pandemic caused by the SARS-CoV-2 virus has significantly disrupted and burdened the diagnostic workup and delivery of care, including transfusion, to cancer patients across the globe. Furthermore, cancer patients suffering from solid tumors or hematologic malignancies were more prone to the infection and had higher morbidity and mortality than the rest of the population. Major signaling pathways have been identified at the intersection of SARS-CoV-2 and cancer cells, often leading to tumor progression or alteration of the tumor response to therapy. The reactivation of oncogenic viruses has also been alluded to in the context and following COVID-19. Paradoxically, certain tumors responded better following the profound infection-induced immune modulation. Unveiling the mechanisms of the virus-tumor cell interactions will lead to a better understanding of the pathophysiology of both cancer progression and virus propagation. It would be challenging to monitor, through the different cancer registries, retrospectively, the response of patients who have been previously exposed to the virus in contrast to those who have not contracted the infection.


Assuntos
COVID-19 , Neoplasias , Humanos , Neoplasias/terapia , Pandemias , Estudos Retrospectivos , SARS-CoV-2
10.
Transfus Apher Sci ; 61(3): 103459, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: covidwho-1852173

RESUMO

Platelets are at the crossroads between thrombosis and inflammation. When activated, platelets can shed bioactive extracellular vesicles [pEVs] that share the hemostatic potential of their parent cells and act as bioactive shuttles of their granular contents. In a viral infection, platelets are activated, and pEVs are generated with occasional virion integration. Both platelets and pEVs are engaged in a bidirectional interaction with neutrophils and other cells of the immune system and the hemostatic pathways. Severe COVID-19 infection is characterized by a stormy thromboinflammatory response with platelets and their EVs at the center stage of this reaction. This review sheds light on the interactions of platelets, pEVS and SARS-CoV-2 infection and prognostic and potential therapeutic role of pEVs. The review also describes the role of pEVs in the rare adenovirus-based COVID-19 vaccine-induced thrombosis thrombocytopenia.


Assuntos
COVID-19 , Vesículas Extracelulares , Hemostáticos , Trombose , Plaquetas/metabolismo , Vacinas contra COVID-19 , Vesículas Extracelulares/metabolismo , Hemostáticos/metabolismo , Humanos , SARS-CoV-2
11.
Clin Hematol Int ; 3(3): 77-82, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: covidwho-1533606

RESUMO

The use of convalescent plasma (CP) from individuals recovered from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a promising therapeutic modality for the coronavirus disease 2019 (COVID-19). CP has been in use for at least a century to provide passive immunity against a number of diseases, and was recently proposed by the World Health Organization for human Ebola virus infection. Only a few small studies have so far been published on patients with COVID-19 and concomitant hematological malignancies (HM). The Italian Hematology Alliance on HM and COVID-19 has found that HM patients with COVID-19 clinically perform more poorly than those with either HM or COVID-19 alone. A COVID-19 infection in patients with B-cell lymphoma is associated with impaired generation of neutralizing antibody titers and lowered clearance of SARS-CoV-2. Treatment with CP was seen to increase antibody titers in all patients and to improve clinical response in 80% of patients examined. However, a recent study has reported impaired production of SARS-CoV-2-neutralizing antibodies in an immunosuppressed individual treated with CP, possibly supporting the notion of virus escape, particularly in immunocompromised individuals where prolonged viral replication occurs. This may limit the efficacy of CP treatment in at least some HM patients. More recently, it has been shown that CP may provide a neutralising effect against B.1.1.7 and other SARS-CoV-2 variants, thus expanding its application in clinical practice. More extensive studies are needed to further assess the use of CP in COVID-19-infected HM patients.

13.
Trends in Transplantation ; 14(2):1-3, 2021.
Artigo em Inglês | Academic Search Complete | ID: covidwho-1209699

RESUMO

As the one shot is probably sufficient, as there is some level of antibodies against the virus exist in people who were already infected and with one shot, they basically develop the level of antibodies that most people get with two shots of vaccine;b] Is the infection has primed the immune system and the on shot vaccine is effectively boosting those existing immune responses? This concept is also supported by a new trial on Moderna' vaccine, using the same vaccination principle, than the Pfizer vaccine, indicating that that a single dose is effective after 2 months of vaccination. However, in support of the UK decision it should be mentioned that the one dose of Pfizer/BioNTech's COVID-19 vaccine is 51% effective at preventing both symptomatic and asymptomatic SARS-CoV-2 infection and this level of efficacy meets the WHO acceptance criteria for the useful vaccine to be equal or over 50% efficacy. [Extracted from the article] Copyright of Trends in Transplantation is the property of Publicidad Permanyer SLU and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

14.
Trends in Transplantation ; 14(2):1-4, 2021.
Artigo em Inglês | Academic Search Complete | ID: covidwho-1209116
17.
Transfus Apher Sci ; 59(5): 102934, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: covidwho-748037

RESUMO

This communication provides a compilation on aspects of COVID-19 infection control measures, describes the potential role of therapeutic plasma exchange to reduce fatality rates, addresses precautions concerning dexamethasone pharmacotherapy and updates the current status on the availability of vaccines. As part of passive immunotherapy, it focuses on various blood derivatives. These include coronavirus neutralising antibodies extracted from different sources to be administered as a pure hyper concentrate intramuscularly or for upgrading and standardising the specific potency of high affinity antibodies. These processes are intended to compose standardised pooled bioproducts of corona convalescent plasma/cryosupernatant that are pathogen inactivated for additional safety by well-established UV technologies. For the best practice of optimising plasma exchange, hyper concentrate NAb should be added to the cryosupernatant, which contains some of the active principles of corona convalescent plasma. The cryosupernatant apart from the high molecular weight viscous part of cold insoluble proteins that are removed, is equivalent to CCP, but makes it safer for general application. Such a bioproduct is often used routinely for substitution therapy of thrombotic thrombocytopaenic purpura. Alternative resources of large-scale specific coronavirus antibodies warrant further exploration such as cadaveric donations. The early uses of therapeutic plasma exchange and low molecular weight heparin, for any clinical trial in development is warranted, in order to interdict the intense inflammatory/kinin driven cascade. Because coronavirus positive patients are highly prone to thrombosis, thromboprophylaxis is necessary, even some time after recovery guided by the laboratory data.


Assuntos
Corticosteroides/uso terapêutico , Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , COVID-19/terapia , COVID-19/epidemiologia , Ensaios Clínicos como Assunto , Humanos , Imunização Passiva , SARS-CoV-2/fisiologia , Soroterapia para COVID-19
18.
Transfus Apher Sci ; 59(5): 102941, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: covidwho-745914

RESUMO

A shortage of blood during the pandemic outbreak of COVID-19 is a typical example in which the maintenance of a safe and adequate blood supply becomes difficult and highly demanding. So far, human RBCs have been produced in vitro using diverse sources: hematopoietic stem cells (SCs), embryonic SCs and induced pluripotent SCs. The existing, even safest core of conventional cellular bioproducts destined for transfusion have some shortcoming in respects to: donor -dependency variability in terms of hematological /immunological and process/ storage period issues. SCs-derived transfusable RBC bioproducts, as one blood group type for all, were highly complex to work out. Moreover, the strategies for their successful production are often dependent upon the right selection of starting source materials and the composition and the stability of the right expansion media and the strict compliance to GMP regulatory processes. In this mini-review we highlight some model studies, which showed that the efficiency and the functionality of RBCs that could be produced by the various types of SCs, in relation to the in-vitro culture procedures are such that they may, potentially, be used at an industrial level. However, all cultured products do not have an unlimited life due to the critical metabolic pathways or the metabolites produced. New bioreactors are needed to remove these shortcomings and the development of a new mouse model is required. Modern clinical trials based on the employment of regenerative medicine approaches in combination with novel large-scale bioengineering tools, could overcome the current obstacles in artificial RBC substitution, possibly allowing an efficient RBC industrial production.


Assuntos
Transfusão de Sangue , Eritrócitos/citologia , Células-Tronco Hematopoéticas/citologia , Linhagem Celular , Ensaios Clínicos como Assunto , Humanos
19.
Transfus Apher Sci ; 59(5): 102933, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: covidwho-741520

RESUMO

COVID-19 convalescent plasma (CCP) therapy involves the use of circulating antibodies administration from recovered COVID 19 patients as a practical strategy to provide immediate passive immunity in susceptible recipients in need. Global concern over the potential for "second" or "third" waves of infection to occur before effective vaccines or drug therapies are available has many looking at other biological sources for large-scale production of neutralizing SARS-CoV-2 antibodies. This report summarizes some of the novel strategies for developing alternative safe sources of therapeutic autologous antibodies from COVID -19 infected patients, and provides some original thoughts on how to rapidly implement a safe passive immunity in those COVID-19 patients who are most in need of intervention. COVID-19 antibodies can be isolated or delivered using a number of other techniques including: plasmapheresis, plasma cryoprecipitate reduced (cryosupernatant), antibody hyperconcentrates and advanced cell-based delivery systems. While these proposed technological options may, in some cases, be theoretical, the growing concern over the rapid spread of the SARS-CoV-2 virus has prompted many to pursue innovative and creative solutions to reduce the mortality and morbidity resulting from the current global pandemic. A comparative analysis of various strategies currently in use deserved exploring and this highlighted separately as the essential part of this concise theme.


Assuntos
COVID-19/terapia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , COVID-19/virologia , Sistemas de Liberação de Medicamentos , Humanos , Plasmaferese , SARS-CoV-2/imunologia , SARS-CoV-2/fisiologia
20.
Transfus Apher Sci ; 59(3): 102804, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: covidwho-154626

RESUMO

Covid-19 is characterized by weak symptoms in most affected patients whilst severe clinical complications, with frequent fatal issues, occur in others. Disease severity is associated with age and comorbidities. Understanding of viral infectious mechanisms, and antibody immune response, can help to better control disease progression. SARS-CoV-2 has a major impact on the Renin Angiotensin Aldosterone System (RAAS), through its binding to the membrane cellular glycoprotein, Angiotensin Converting Enzyme-2 (ACE-2), then infecting cells for replication. This report hypothesizes the possible implication of an autoimmune response, induced by generation of allo- or autoantibodies to ACE-2, or to its complexes with viral spike protein. This could contribute to some delayed severe complications occurring in affected patients. We also propose a strategy for investigating this eventuality.


Assuntos
Anticorpos Antivirais/imunologia , Autoanticorpos/imunologia , Autoimunidade , Betacoronavirus/imunologia , Coagulação Sanguínea , Infecções por Coronavirus/sangue , Isoanticorpos/imunologia , Peptidil Dipeptidase A/imunologia , Pneumonia Viral/sangue , Sistema Renina-Angiotensina/fisiologia , Trombofilia/etiologia , Enzima de Conversão de Angiotensina 2 , Especificidade de Anticorpos , COVID-19 , Infecções por Coronavirus/complicações , Infecções por Coronavirus/imunologia , Síndrome da Liberação de Citocina/etiologia , Síndrome da Liberação de Citocina/imunologia , Progressão da Doença , Coagulação Intravascular Disseminada/etiologia , Humanos , Pandemias , Peptidil Dipeptidase A/sangue , Peptidil Dipeptidase A/fisiologia , Pneumonia Viral/complicações , Pneumonia Viral/imunologia , SARS-CoV-2 , Serina Endopeptidases/fisiologia , Índice de Gravidade de Doença , Glicoproteína da Espícula de Coronavírus/imunologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Trombofilia/sangue , Trombofilia/imunologia , Fatores de Tempo
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