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The Lancet. Infectious Diseases May 2023The global surge in the omicron (B.1.1.529) variant has resulted in many individuals with hybrid immunity (immunity developed through a combination of SARS-CoV-2...
BACKGROUND
The global surge in the omicron (B.1.1.529) variant has resulted in many individuals with hybrid immunity (immunity developed through a combination of SARS-CoV-2 infection and vaccination). We aimed to systematically review the magnitude and duration of the protective effectiveness of previous SARS-CoV-2 infection and hybrid immunity against infection and severe disease caused by the omicron variant.
METHODS
For this systematic review and meta-regression, we searched for cohort, cross-sectional, and case-control studies in MEDLINE, Embase, Web of Science, ClinicalTrials.gov, the Cochrane Central Register of Controlled Trials, the WHO COVID-19 database, and Europe PubMed Central from Jan 1, 2020, to June 1, 2022, using keywords related to SARS-CoV-2, reinfection, protective effectiveness, previous infection, presence of antibodies, and hybrid immunity. The main outcomes were the protective effectiveness against reinfection and against hospital admission or severe disease of hybrid immunity, hybrid immunity relative to previous infection alone, hybrid immunity relative to previous vaccination alone, and hybrid immunity relative to hybrid immunity with fewer vaccine doses. Risk of bias was assessed with the Risk of Bias In Non-Randomized Studies of Interventions Tool. We used log-odds random-effects meta-regression to estimate the magnitude of protection at 1-month intervals. This study was registered with PROSPERO (CRD42022318605).
FINDINGS
11 studies reporting the protective effectiveness of previous SARS-CoV-2 infection and 15 studies reporting the protective effectiveness of hybrid immunity were included. For previous infection, there were 97 estimates (27 with a moderate risk of bias and 70 with a serious risk of bias). The effectiveness of previous infection against hospital admission or severe disease was 74·6% (95% CI 63·1-83·5) at 12 months. The effectiveness of previous infection against reinfection waned to 24·7% (95% CI 16·4-35·5) at 12 months. For hybrid immunity, there were 153 estimates (78 with a moderate risk of bias and 75 with a serious risk of bias). The effectiveness of hybrid immunity against hospital admission or severe disease was 97·4% (95% CI 91·4-99·2) at 12 months with primary series vaccination and 95·3% (81·9-98·9) at 6 months with the first booster vaccination after the most recent infection or vaccination. Against reinfection, the effectiveness of hybrid immunity following primary series vaccination waned to 41·8% (95% CI 31·5-52·8) at 12 months, while the effectiveness of hybrid immunity following first booster vaccination waned to 46·5% (36·0-57·3) at 6 months.
INTERPRETATION
All estimates of protection waned within months against reinfection but remained high and sustained for hospital admission or severe disease. Individuals with hybrid immunity had the highest magnitude and durability of protection, and as a result might be able to extend the period before booster vaccinations are needed compared to individuals who have never been infected.
FUNDING
WHO COVID-19 Solidarity Response Fund and the Coalition for Epidemic Preparedness Innovations.
Topics: Humans; COVID-19; SARS-CoV-2; Cross-Sectional Studies; Reinfection; Adaptive Immunity
PubMed: 36681084
DOI: 10.1016/S1473-3099(22)00801-5 -
Frontiers in Immunology 2022Recovery from coronavirus disease 2019 (COVID-19) can be impaired by the persistence of symptoms or new-onset health complications, commonly referred to as Long COVID.... (Review)
Review
BACKGROUND
Recovery from coronavirus disease 2019 (COVID-19) can be impaired by the persistence of symptoms or new-onset health complications, commonly referred to as Long COVID. In a subset of patients, Long COVID is associated with immune system perturbations of unknown etiology, which could be related to compromised immunoregulatory mechanisms.
OBJECTIVE
The objective of this scoping review was to summarize the existing literature regarding the frequency and functionality of Tregs in convalescent COVID-19 patients and to explore indications for their potential involvement in the development of Long COVID.
DESIGN
A systematic search of studies investigating Tregs during COVID-19 convalescence was conducted on MEDLINE ( Pubmed) and Web of Science.
RESULTS
The literature search yielded 17 relevant studies, of which three included a distinct cohort of patients with Long COVID. The reviewed studies suggest that the Treg population of COVID-19 patients can reconstitute quantitatively and functionally during recovery. However, the comparison between recovered and seronegative controls revealed that an infection-induced dysregulation of the Treg compartment can be sustained for at least several months. The small number of studies investigating Tregs in Long COVID allowed no firm conclusions to be drawn about their involvement in the syndrome's etiology. Yet, even almost one year post-infection Long COVID patients exhibit significantly altered proportions of Tregs within the CD4+ T cell population.
CONCLUSIONS
Persistent alterations in cell frequency in Long COVID patients indicate that Treg dysregulation might be linked to immune system-associated sequelae. Future studies should aim to address the association of Treg adaptations with different symptom clusters and blood parameters beyond the sole quantification of cell frequencies while adhering to consensualized phenotyping strategies.
Topics: Humans; CD4-Positive T-Lymphocytes; COVID-19; Post-Acute COVID-19 Syndrome; T-Lymphocytes, Regulatory
PubMed: 36582234
DOI: 10.3389/fimmu.2022.1070994 -
Molecular Psychiatry Mar 2023Meta-analyses implicate immune dysfunction in depression confirming increased levels of circulating immune proteins (e.g., cytokines) in depression cases compared to... (Meta-Analysis)
Meta-Analysis
INTRODUCTION
Meta-analyses implicate immune dysfunction in depression confirming increased levels of circulating immune proteins (e.g., cytokines) in depression cases compared to controls. White blood cells (WBC) both produce and are influenced by cytokines, and play key roles in orchestrating innate and adaptive immune responses, but their role in depression remains unclear. Therefore, a systematic review of studies of various WBC subsets in depression is required for a greater understanding of the nature of immune dysfunction in this illness.
METHODS
We searched PubMed and PsycINFO databases (inception to 5 April 2022) and conducted a systematic review and meta-analysis of identified studies comparing absolute count and/or relative percentage of flow cytometry-derived WBC subsets between depression cases and controls. Selected studies were quality assessed. Random-effect meta-analysis was performed.
RESULTS
Thirty-three studies were included and 27 studies (n = 2277) were meta-analysed. We report an increase in mean absolute counts of WBC (seven studies; standardised mean difference [SMD] = 1.07; 95% CI, 0.61-1.53; P < 0.01; I = 64%), granulocytes (two studies; SMD = 2.07; 95% CI, 1.45-2.68; P < 0.01; I = 0%), neutrophils (four studies; SMD = 0.91; 95% CI, 0.23-1.58; P < 0.01; I = 82%), monocytes (seven studies; SMD = 0.60; 95% CI, 0.19-1.01; P < 0.01; I = 66%), CD4 helper T cells (11 studies; SMD = 0.30; 95% CI, 0.15-0.45; P < 0.01; I = 0%), natural killer cells (11 studies; SMD = 1.23; 95% CI, 0.38-2.08; P < 0.01; I = 95%), B cells (10 studies; SMD = 0.30; 95% CI, 0.03-0.57; P = 0.03; I = 56%), and activated T cells (eight studies; SMD = 0.45; 95% CI, 0.24-0.66; P < 0.01; I = 0%) in depression, compared to controls. Fewer studies reported relative percentage, indicating increased neutrophils and decreased total lymphocytes, Th1, and Th2 cells in depression.
CONCLUSIONS
Depression is characterised by widespread alterations in circulating myeloid and lymphoid cells, consistent with dysfunction in both innate and adaptive immunity. Immune cells could be useful biomarkers for illness subtyping and patient stratification in future immunotherapy trials of depression, along with cytokines, other biomarkers, and clinical measures.
Topics: Humans; Depression; Biomarkers
PubMed: 36577838
DOI: 10.1038/s41380-022-01919-7 -
Influenza and Other Respiratory Viruses Jan 2023COVID-19 vaccine is critical in preventing SARS-CoV-2 infection and transmission. However, obesity's effect on immune responses to COVID-19 vaccines is still unknown. We... (Meta-Analysis)
Meta-Analysis Review
COVID-19 vaccine is critical in preventing SARS-CoV-2 infection and transmission. However, obesity's effect on immune responses to COVID-19 vaccines is still unknown. We performed a meta-analysis of the literature and compared antibody responses with COVID-19 vaccines among persons with and without obesity. We used Pubmed, Embase, Web of Science, and Cochrane Library to identify all related studies up to April 2022. The Stata.14 software was used to analyze the selected data. Eleven studies were included in the present meta-analysis. Five of them provided absolute values of antibody titers in the obese group and non-obese group. Overall, we found that the obese population was significantly associated with lower antibody titers (standardized mean difference [SMD] = -0.228, 95% CI [-0.437, -0.019], P < 0.001) after COVID-19 vaccination. Significant heterogeneity was present in most pooled analyses but was reduced after subgroup analyses. No publication bias was observed in the present analysis. The Trim and Fill method did not change the results in the primary analysis. The present meta-analysis suggested that obesity was significantly associated with decreased antibody responses to SARS-CoV-2 vaccines. Future studies should be performed to unravel the mechanism of response to the COVID-19 vaccine in obese individuals.
Topics: Humans; COVID-19 Vaccines; Antibody Formation; COVID-19; SARS-CoV-2; Vaccination; Obesity
PubMed: 36535669
DOI: 10.1111/irv.13078 -
International Journal of Molecular... Nov 2022Melanoma is the most aggressive form of skin cancer, characterized by life-threatening and rapidly spreading progression. Traditional targeted therapy can alleviate... (Review)
Review
Melanoma is the most aggressive form of skin cancer, characterized by life-threatening and rapidly spreading progression. Traditional targeted therapy can alleviate tumors by inactivating hyperactive kinases such as BRAF or MEK but inevitably encounters drug resistance. The advent of immunotherapy has revolutionized melanoma treatment and significantly improved the prognosis of melanoma patients. MicroRNAs (miRNAs) are intricately involved in innate and adaptive immunity and are implicated in melanoma immunotherapy. This systematic review describes the roles of miRNAs in regulating the functions of immune cells in skin and melanoma, as well as the involvement of miRNAs in pharmacology including the effect, resistance and immune-related adverse events of checkpoint inhibitors such as PD-1 and CTLA-4 inhibitors, which are used for treating cutaneous, uveal and mucosal melanoma. The expressions and functions of miRNAs in immunotherapy employing tumor-infiltrating lymphocytes and Toll-like receptor 9 agonists are also discussed. The prospect of innovative therapeutic strategies such as the combined administration of miRNAs and immune checkpoint inhibitors and the nanotechnology-based delivery of miRNAs are also provided. A comprehensive understanding of the interplay between miRNAs and immunotherapy is crucial for the discovery of reliable biomarkers and for the development of novel miRNA-based therapeutics against melanoma.
Topics: Humans; MicroRNAs; Melanoma; Immunotherapy; Skin Neoplasms; Combined Modality Therapy
PubMed: 36499102
DOI: 10.3390/ijms232314775 -
Frontiers in Immunology 2022There is evidence that the adaptive or acquired immune system is one of the crucial variables in differentiating the course of coronavirus disease 2019 (COVID-19),...
BACKGROUND
There is evidence that the adaptive or acquired immune system is one of the crucial variables in differentiating the course of coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This work aimed to analyze the immunopathological aspects of adaptive immunity that are involved in the progression of this disease.
METHODS
This is a systematic review based on articles that included experimental evidence from assays, cohort studies, reviews, cross-sectional and case-control studies from PubMed, SciELO, MEDLINE, and Lilacs databases in English, Portuguese, or Spanish between January 2020 and July 2022.
RESULTS
Fifty-six articles were finalized for this review. CD4+ T cells were the most resolutive in the health-disease process compared with B cells and CD8+ T lymphocytes. The predominant subpopulations of T helper lymphocytes (Th) in critically ill patients are Th1, Th2, Th17 (without their main characteristics) and regulatory T cells (Treg), while in mild cases there is an influx of Th1, Th2, Th17 and follicular T helper cells (Tfh). These cells are responsible for the secretion of cytokines, including interleukin (IL) - 6, IL-4, IL-10, IL-7, IL-22, IL-21, IL-15, IL-1α, IL-23, IL-5, IL-13, IL-2, IL-17, tumor necrosis factor alpha (TNF-α), CXC motivating ligand (CXCL) 8, CXCL9 and tumor growth factor beta (TGF-β), with the abovementioned first 8 inflammatory mediators related to clinical benefits, while the others to a poor prognosis. Some CD8+ T lymphocyte markers are associated with the severity of the disease, such as human leukocyte antigen (HLA-DR) and programmed cell death protein 1 (PD-1). Among the antibodies produced by SARS-CoV-2, Immunoglobulin (Ig) A stood out due to its potent release associated with a more severe clinical form.
CONCLUSIONS
It is concluded that through this study it is possible to have a brief overview of the main immunological biomarkers and their function during SARS-CoV-2 infection in particular cell types. In critically ill individuals, adaptive immunity is varied, aberrantly compromised, and late. In particular, the T-cell response is also an essential and necessary component in immunological memory and therefore should be addressed in vaccine formulation strategies.
Topics: Humans; COVID-19; Programmed Cell Death 1 Receptor; SARS-CoV-2; Interleukin-10; Interleukin-15; Interleukin-17; Interleukin-13; Tumor Necrosis Factor-alpha; Cross-Sectional Studies; Critical Illness; Ligands; Interleukin-2; Interleukin-4; Interleukin-5; Interleukin-7; Adaptive Immunity; HLA-DR Antigens; Interleukin-23; Inflammation Mediators; Transforming Growth Factor beta; Immunoglobulins
PubMed: 36300105
DOI: 10.3389/fimmu.2022.1001198 -
British Journal of Cancer Nov 2022Patients living with cancer are at a significantly increased risk of morbidity and mortality after infection with severe acute respiratory syndrome coronavirus-2...
BACKGROUND
Patients living with cancer are at a significantly increased risk of morbidity and mortality after infection with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). This systematic review aims to investigate the current available evidence about the immunogenicity of SARS-CoV-2 booster vaccines in patients living with cancer.
METHODS
A systematic search was undertaken for studies published until March 1, 2022. A systematic narrative review was undertaken to include all studies that evaluated the efficacy of booster vaccines against SARS-CoV-2 in patients with cancer.
RESULTS
Fifteen studies encompassing 1205 patients with cancer were included. We found that a booster vaccine dose induced a higher response in patients with solid cancer as compared to haematological malignancies. Recent systemic anticancer therapy does not appear to affect seroconversion in solid organ malignancies, however, there is an association between B-cell depleting therapies and poor seroconversion in haematological patients.
CONCLUSIONS
Third booster vaccination induces an improved antibody response to SARS-CoV-2 in adults with haematological and solid cancer, relative to patients who only receive two doses. Access to vaccination boosters should be made available to patients at risk of poor immunological responses, and the provision of fourth doses may be of benefit to this vulnerable population.
REGISTRATION
PROSPERO number CRD42021270420.
Topics: Adult; Humans; Antibodies, Viral; Antibody Formation; COVID-19; COVID-19 Vaccines; Neoplasms; SARS-CoV-2; Vaccination; Viral Vaccines
PubMed: 36224402
DOI: 10.1038/s41416-022-01951-y -
International Journal of... 2022The B.1.1.529 (Omicron) variant of SARS-CoV-2 is the most antigenically unique SARS-CoV-2 variant of concern to date, which is currently widespread across the world....
INTRODUCTION
The B.1.1.529 (Omicron) variant of SARS-CoV-2 is the most antigenically unique SARS-CoV-2 variant of concern to date, which is currently widespread across the world. Omicron variant and its sublineages contain a plethora of mutations than other variants of concern, which increases their transmissibility and virulence. Concerns regarding potential immunological evasion have been reignited by emerging subvariants of the Omicron variant. Determining the effectiveness of Omicron-induced immunity and whether it is cross-protective against other variants is a crucial aspect of the research.
METHOD
A systematic search of relevant articles until September 25, 2022, from databases such as PubMed, Scopus, Google Scholar, and ScienceDirect was done independently by two authors. A total of 11 articles discussing about immunological evasion of different Omicron subvariants were included in the study.
RESULTS
Numerous studies have demonstrated that Omicron variant causes a restricted immune response after infection. Omicron infection boosts preexisting vaccine-induced immunity, but it may not be enough to establish widespread, cross-neutralizing humoral immunity in unvaccinated people.
CONCLUSION
Due to co-circulation and the emergence of novel SARS-CoV-2 variants, findings highlight the importance of booster vaccinations for immune protection. More studies should focus on the efficacy of Omicron-induced immunity, its cross-protective properties against other variants, and development of a universal vaccine.
Topics: COVID-19; COVID-19 Vaccines; Humans; Immunity, Humoral; SARS-CoV-2
PubMed: 36214233
DOI: 10.1177/03946320221133001 -
Haematologica Feb 2023
Meta-Analysis
Topics: Adult; Humans; SARS-CoV-2; Antibody Formation; COVID-19; Hematologic Neoplasms; Vaccination; Antibodies, Viral
PubMed: 36172816
DOI: 10.3324/haematol.2022.281902 -
International Journal of Biological... 2022Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has undergone multiple mutations since its emergence, and its latest variant, Omicron (B.1.1.529), is the...
Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has undergone multiple mutations since its emergence, and its latest variant, Omicron (B.1.1.529), is the most contagious variant of concern (VOC) which poses a major and imminent threat to public health. Since firstly reported by World Health Organization (WHO) in November 2021, Omicron variant has been spreading rapidly and has become the dominant variant in many countries worldwide. Omicron is the most mutated variant so far, containing 60 mutations in its genome, including 37 mutations in the S-protein. Since all current COVID-19 vaccines in use were developed based on ancestral SARS-CoV-2 strains, whether they are protective against Omicron is a critical question which has been the center of study currently. In this article, we systemically reviewed the studies regarding the effectiveness of 2- or 3-dose vaccines delivered in either homologous or heterologous manner. The humoral and cellular immune responses elicited by various vaccine regimens to protect against Omicron variant are discussed. Current understanding of the molecular basis underlying immune escape of Omicron was also analyzed. These studies indicate that two doses of vaccination are insufficient to elicit neutralizing antibody responses against Omicron variant. Nevertheless, Omicron-specific humoral immune responses can be enhanced by booster dose of almost all type vaccines in certain degree, and heterologous vaccination strategy may represent a better choice than homogenous regimens. Intriguingly, results of studies indicate that all current vaccines are still able to elicit robust T cell response against Omicron. Future focus should be the development of Omicron variant vaccine, which may induce potent humoral as well as cellular immune responses simultaneously against all known variants of the SARS-CoV-2 virus.
Topics: Humans; COVID-19; COVID-19 Vaccines; Immunity, Cellular; SARS-CoV-2; Viral Vaccines
PubMed: 35874952
DOI: 10.7150/ijbs.73583