Waning cellular immune responses and predictive factors in maintaining cellular immunity against SARS-CoV-2 six months after BNT162b2 mRNA vaccination.

Several clinical trials have shown that the humoral response produced by anti-spike antibodies elicited by coronavirus disease 2019 (COVID-19) vaccines gradually declines. The kinetics, durability and influence of epidemiological and clinical factors on cellular immunity have not been fully elucidated. We analyzed cellular immune responses elicited by BNT162b2 mRNA vaccines in 321 health care workers using whole blood interferon-gamma (IFN-γ) release assays. IFN-γ, induced by CD4 + and CD8 + T cells stimulated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike epitopes (Ag2), levels were highest at 3 weeks after the second vaccination (6 W) and decreased by 37.4% at 3 months (4 M) and 60.0% at 6 months (7 M), the decline of which seemed slower than that of anti-spike antibody levels. Multiple regression analysis revealed that the levels of IFN-γ induced by Ag2 at 7 M were significantly correlated with age, dyslipidemia, focal adverse reactions to full vaccination, lymphocyte and monocyte counts in whole blood, Ag2 levels before the second vaccination, and Ag2 levels at 6 W. We clarified the dynamics and predictive factors for the long-lasting effects of cellular immune responses. The results emphasize the need for a booster vaccine from the perspective of SARS-CoV-2 vaccine-elicited cellular immunity.

Multicenter, single-blind, randomized controlled study of the efficacy and safety of favipiravir and nafamostat mesilate in patients with COVID-19 pneumonia.

OBJECTIVES: To evaluate the efficacy and safety of nafamostat combined with favipiravir for the treatment of COVID-19. METHODS: We conducted a multicenter, randomized, single-blind, placebo-controlled, parallel assignment study in hospitalized patients with mild-to-moderate COVID-19 pneumonia. Patients were randomly assigned to receive favipiravir alone (n = 24) or nafamostat with favipiravir (n = 21). The outcomes included changes in the World Health Organization clinical progression scale score, time to improvement in body temperature, and improvement in oxygen saturation (SpO2). RESULTS: There was no significant difference in the changes in the clinical progression scale between nafamostat with favipiravir and favipiravir alone groups (median, -0.444 vs -0.150, respectively; least-squares mean difference, -0.294; P = 0.364). The time to improvement in body temperature was significantly shorter in the combination group (5.0 days; 95% confidence interval, 4.0-7.0) than in the favipiravir group (9.0 days; 95% confidence interval, 7.0-18.0; P =0.009). The changes in SpO2 were greater in the combination group than in the favipiravir group (0.526% vs -1.304%, respectively; least-squares mean difference, 1.831; P = 0.022). No serious adverse events or deaths were reported, but phlebitis occurred in 57.1% of the patients in the combination group. CONCLUSION: Although our study showed no differences in clinical progression, earlier defervescence, and recovery of SpO2 were observed in the combination group.

Dynamic modulations of urinary sphingolipid and glycerophospholipid levels in COVID-19 and correlations with COVID-19-associated kidney injuries.

BACKGROUND: Among various complications of coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), renal complications, namely COVID-19-associated kidney injuries, are related to the mortality of COVID-19. METHODS: In this retrospective cross-sectional study, we measured the sphingolipids and glycerophospholipids, which have been shown to possess potent biological properties, using liquid chromatography-mass spectrometry in 272 urine samples collected longitudinally from 91 COVID-19 subjects and 95 control subjects without infectious diseases, to elucidate the pathogenesis of COVID-19-associated kidney injuries. RESULTS: The urinary levels of C18:0, C18:1, C22:0, and C24:0 ceramides, sphingosine, dihydrosphingosine, phosphatidylcholine, lysophosphatidylcholine, lysophosphatidic acid, and phosphatidylglycerol decreased, while those of phosphatidylserine, lysophosphatidylserine, phosphatidylethanolamine, and lysophosphatidylethanolamine increased in patients with mild COVID-19, especially during the early phase (day 1-3), suggesting that these modulations might reflect the direct effects of infection with SARS-CoV-2. Generally, the urinary levels of sphingomyelin, ceramides, sphingosine, dihydrosphingosine, dihydrosphingosine L-phosphate, phosphatidylcholine, lysophosphatidic acid, phosphatidylserine, lysophosphatidylserine, phosphatidylethanolamine, lysophosphatidylethanolamine, phosphatidylglycerol, lysophosphatidylglycerol, phosphatidylinositol, and lysophosphatidylinositol increased, especially in patients with severe COVID-19 during the later phase, suggesting that their modulations might result from kidney injuries accompanying severe COVID-19. CONCLUSIONS: Considering the biological properties of sphingolipids and glycerophospholipids, an understanding of their urinary modulations in COVID-19 will help us to understand the mechanisms causing COVID-19-associated kidney injuries as well as general acute kidney injuries and may prompt researchers to develop laboratory tests for predicting maximum severity and/or novel reagents to suppress the renal complications of COVID-19.

Decrease in serum levels of autotaxin in COVID-19 patients.

INTRODUCTION: In order to identify therapeutic targets in Coronavirus disease 2019 (COVID-19), it is important to identify molecules involved in the biological responses that are modulated in COVID-19. Lysophosphatidic acids (LPAs) are involved in the pulmonary inflammation and fibrosis are one of the candidate molecules. The aim of this study was to evaluate the association between the serum levels of autotaxin (ATX), which are enzymes involved in the synthesis of lysophosphatidic acids. MATERIAL AND METHODS: We enrolled 134 subjects with COVID-19 and 58 normal healthy subjects for the study. We measured serum ATX levels longitudinally in COVID-19 patients and investigated the time course and the association with severity and clinical parameters. RESULTS: The serum ATX levels were reduced in all patients with COVID-19, irrespective of the disease severity, and were negatively associated with the serum CRP, D-dimer, and anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody levels. DISCUSSION: Considering the biological properties of LPAs in the pulmonary inflammation and fibrosis, modulation of ATX might be compensatory biological responses to suppress immunological overreaction especially in the lung, which is an important underlying mechanism for the mortality of the disease. CONCLUSIONS: COVID-19 patients showed a decrease in the serum levels of ATX, irrespective of the disease severity. Key MessagesAutotaxin (ATX) is an enzyme involved in the synthesis of lysophosphatidic acid (LPA), which has been reported to be involved in pulmonary inflammation and fibrosis. Patients with COVID-19 show decrease in the serum levels of ATX. Modulation of ATX might be compensatory biological responses to suppress immunological overreaction.

Japanese rapid/living recommendations on drug management for COVID-19: updated guidelines (July 2022).

Background: Coronavirus disease (COVID-19), an infectious disease caused by the novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread worldwide since early 2020, and there are still no signs of resolution. The Japanese Clinical Practice Guidelines for the Management of Sepsis and Septic Shock (J-SSCG) 2020 Special Committee created the Japanese Rapid/Living recommendations on drug management for COVID-19 using the experience of creating the J-SSCG. Methods: The Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) approach was used to determine the certainty of the evidence and strength of recommendations. The first edition of this guideline was released on September 9, 2020, and this is the revised edition (version 5.0; released on July 15, 2022). Clinical questions (CQs) were set for the following 10 drugs: favipiravir (CQ1), remdesivir (CQ2), corticosteroids (CQ4), tocilizumab (CQ5), anticoagulants (CQ7), baricitinib (CQ8), casirivimab/imdevimab (CQ9-1), sotrovimab (CQ9-2), molnupiravir (CQ10), and nirmatrelvir/ritonavir (CQ11). Recommendations: Favipiravir is not suggested for all patients with COVID-19 (GRADE 2C). Remdesivir is suggested for patients with mild COVID-19 who do not require oxygen, and patients with moderate COVID-19 requiring supplemental oxygen/hospitalization (both GRADE 2B). Corticosteroids are recommended for moderate and severe COVID-19 (GRADE 1B, 1A). However, their administration is not recommended for mild COVID-19 (GRADE 1B). Tocilizumab is suggested for moderate and severe COVID-19 (GRADE 2B, 2C). Anticoagulant administration is recommended for moderate and severe COVID-19 (Good Practice Statement). Baricitinib is suggested for moderate and severe COVID-19 (both GRADE 2C). Casirivimab/imdevimab and sotrovimab are recommended for mild COVID-19 (both GRADE 2C). Molnupiravir and nirmatrelvir/ritonavir are recommended for mild COVID-19 (both GRADE 2C). SARS-CoV-2 mutant strains emerge occasionally, and each time, the treatment policy at clinics is forced to change drastically. We ask health-care professionals in the field to refer to the recommendations in these guidelines and use these to keep up to date with COVID-19 epidemiological information.

Dynamic modulations of sphingolipids and glycerophospholipids in COVID-19.

BACKGROUND: A heterogeneous clinical phenotype is a characteristic of coronavirus disease 2019 (COVID-19). Therefore, investigating biomarkers associated with disease severity is important for understanding the mechanisms responsible for this heterogeneity and for developing novel agents to prevent critical conditions. This study aimed to elucidate the modulations of sphingolipids and glycerophospholipids, which have been shown to possess potent biological properties. METHODS: We measured the serum sphingolipid and glycerophospholipid levels in a total of 887 samples from 215 COVID-19 subjects, plus 115 control subjects without infectious diseases and 109 subjects with infectious diseases other than COVID-19. RESULTS: We observed the dynamic modulations of sphingolipids and glycerophospholipids in the serum of COVID-19 subjects, depending on the time course and severity. The elevation of C16:0 ceramide and lysophosphatidylinositol and decreases in C18:1 ceramide, dihydrosphingosine, lysophosphatidylglycerol, phosphatidylglycerol and phosphatidylinositol were specific to COVID-19. Regarding the association with maximum severity, phosphatidylinositol and phosphatidylcholine species with long unsaturated acyl chains were negatively associated, while lysophosphatidylethanolamine and phosphatidylethanolamine were positively associated with maximum severity during the early phase. Lysophosphatidylcholine and phosphatidylcholine had strong negative correlations with CRP, while phosphatidylethanolamine had strong positive ones. C16:0 ceramide, lysophosphatidylcholine, phosphatidylcholine and phosphatidylethanolamine species with long unsaturated acyl chains had negative correlations with D-dimer, while phosphatidylethanolamine species with short acyl chains and phosphatidylinositol had positive ones. Several species of phosphatidylcholine, phosphatidylethanolamine and sphingomyelin might serve as better biomarkers for predicting severe COVID-19 during the early phase than CRP and D-dimer. Compared with the lipid modulations seen in mice treated with lipopolysaccharide, tissue factor, or histone, the lipid modulations observed in severe COVID-19 were most akin to those in mice administered lipopolysaccharide. CONCLUSION: A better understanding of the disturbances in sphingolipids and glycerophospholipids observed in this study will prompt further investigation to develop laboratory testing for predicting maximum severity and/or novel agents to suppress the aggravation of COVID-19.

The association between adverse reactions and immune response against SARS-CoV-2 spike protein after vaccination with BNT162b2 among healthcare workers in a single healthcare system: a prospective observational cohort study.

Adverse reactions after vaccination with COVID-19 mRNA vaccines are common; however, the association between adverse reactions and humoral responses is uncertain. To determine whether humoral immune responses after BNT162b2 vaccine administration were associated with local and systemic adverse reactions, we conducted a prospective observational cohort study in a single tertiary referral center. Healthcare workers who received the first dose of BNT162b2 vaccine were recruited. SARS-CoV-2 anti-spike IgG antibody titers were measured three weeks after the second dose and information about adverse reactions after vaccination was collected. Among the 887 participants, 641 (72.3%) were women. The median age was 38 (range, 22-74) years. All but one showed anti-spike IgG levels well above the cutoff, with a median level of 13,600 arbitrary units/mL. Overall, 800 (92.2%) participants reported some reactions after the first dose and 822 (96.3%) after the second dose. Significantly more participants reported systemic reactions after the second dose than after the first dose (P < .01), and 625 (73.6%) reported that reactions were stronger after the second dose. Factors positively associated with elevation of anti-spike IgG levels were history of asthma (24% higher if present, P = .01) and stronger reactions after the second dose (19% higher if experienced, P = .02). The majority of participants showed good humoral responses and reported some adverse reactions after vaccination. Anti-spike IgG levels were significantly higher if adverse reactions after the second dose were stronger than those after the first dose. These findings may help inform current and future vaccine recipients.

Japanese rapid/living recommendations on drug management for COVID-19: updated guidelines (September 2021).

BACKGROUND: The coronavirus disease 2019 (COVID-19) has spread worldwide since early 2020, and there are still no signs of resolution. The Japanese Clinical Practice Guidelines for the Management of Sepsis and Septic Shock (J-SSCG) 2020 Special Committee created the Japanese rapid/living recommendations on drug management for COVID-19 using the experience of creating the J-SSCG. METHODS: The Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) approach was used to determine the certainty of the evidence and strength of the recommendations. The first edition of this guideline was released on September 9, 2020, and this document is the revised edition (version 4.0; released on September 9, 2021). Clinical questions (CQs) were set for the following seven drugs: favipiravir (CQ1), remdesivir (CQ2), corticosteroids (CQ4), tocilizumab (CQ5), anticoagulants (CQ7), baricitinib (CQ8), and casirivimab/imdevimab (CQ9). Two CQs (hydroxychloroquine [CQ3] and ciclesonide [CQ6]) were retrieved in this updated version. RECOMMENDATIONS: Favipiravir is not suggested for all patients with COVID-19 (GRADE 2C). Remdesivir is suggested for patients with moderate COVID-19 requiring supplemental oxygen/hospitalization (GRADE 2B). Corticosteroids are recommended for patients with moderate COVID-19 requiring supplemental oxygen/hospitalization (GRADE 1B) and for patients with severe COVID-19 requiring mechanical ventilation/intensive care (GRADE 1A); however, their administration is not recommended for patients with mild COVID-19 not requiring supplemental oxygen (GRADE 1B). Tocilizumab is suggested for patients with moderate COVID-19 requiring supplemental oxygen/hospitalization (GRADE 2B). Anticoagulant administration is recommended for patients with moderate COVID-19 requiring supplemental oxygen/hospitalization and patients with severe COVID-19 requiring mechanical ventilation/intensive care (good practice statement). Baricitinib is suggested for patients with moderate COVID-19 requiring supplemental oxygen/hospitalization (GRADE 2C). Casirivimab/imdevimab is recommended for patients with mild COVID-19 not requiring supplemental oxygen (GRADE 1B). We hope that these updated clinical practice guidelines will help medical professionals involved in the care of patients with COVID-19.

Japanese rapid/living recommendations on drug management for COVID-19.

The coronavirus disease (COVID-19) has spread worldwide since early 2020, and there are still no signs of resolution. The Japanese Clinical Practice Guidelines for the Management of Sepsis and Septic Shock (J-SSCG) 2020 Special Committee created the Japanese rapid/living recommendations on drug management for COVID-19 using the experience of creating the J-SSCGs. The Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) approach was used to determine the certainty of the evidence and strength of the recommendations. The first edition of this guideline was released on 9 September, 2020, and this document is the revised edition (version 3.1) (released 30 March, 2021). Clinical questions (CQs) were set for the following seven drugs: favipiravir (CQ1), remdesivir (CQ2), hydroxychloroquine (CQ3), corticosteroids (CQ4), tocilizumab (CQ5), ciclesonide (CQ6), and anticoagulants (CQ7). Favipiravir is recommended for patients with mild COVID-19 not requiring supplemental oxygen (GRADE 2C); remdesivir for moderate COVID-19 patients requiring supplemental oxygen/hospitalization (GRADE 2B). Hydroxychloroquine is not recommended for all COVID-19 patients (GRADE 1B). Corticosteroids are recommended for moderate COVID-19 patients requiring supplemental oxygen/hospitalization (GRADE 1B) and severe COVID-19 patients requiring ventilator management/intensive care (GRADE 1A); however, their use is not recommended for mild COVID-19 patients not requiring supplemental oxygen (GRADE 1B). Tocilizumab is recommended for moderate COVID-19 patients requiring supplemental oxygen/hospitalization (GRADE 2B). Anticoagulant therapy is recommended for moderate COVID-19 patients requiring supplemental oxygen/hospitalization and severe COVID-19 patients requiring ventilator management/intensive care (GRADE 2C). We hope that these clinical practice guidelines will aid medical professionals involved in the care of COVID-19 patients.

Assessing the impact of non-pharmaceutical interventions on the transmissibility and severity of COVID-19 during the first five months in the Western Pacific Region.

While most countries in the Western Pacific Region (WPR) had similar trajectories of COVID-19 from January to May, their implementations of non-pharmaceutical interventions (NPIs) differed by transmission stages. To offer a better understanding for an implementation of multidisciplinary policies in COVID-19 control, we compared the impact of NPIs by assessing the transmissibility and severity of COVID-19 in different phases of the epidemic during the first five months in WPR. In this study, we estimated the piecewise instantaneous reproduction number (R t ) and the reporting delay-adjusted case-fatality ratio (dCFR) of COVID-19 in seven WPR jurisdictions: Hong Kong Special Administrative Region, Japan, Malaysia, Shanghai, Singapore, South Korea, and Taiwan. According to the results, implementing NPIs was associated with an apparent reduction of the piecewise R t in two epidemic waves in general. However, large cluster outbreaks raised the piecewise R t to a high level. We also observed relaxing the NPIs could result in an increase of R t . The estimated dCFR ranged from 0.09% to 1.59% among the jurisdictions, except in Japan where an estimate of 5.31% might be due to low testing efforts. To conclude, in conjunction with border control measures to reduce influx of imported cases which might cause local outbreaks, other NPIs including social distancing measures along with case finding by rapid tests are also necessary to prevent potential large cluster outbreaks and transmissions from undetected cases. A comparatively lower CFR may reflect the health system capacity of these jurisdictions. In order to keep track of sustained disease transmission due to resumption of economic activities, a close monitoring of disease transmissibility is recommended in the relaxation phase. The report of transmission of SARS CoV-2 to pets in Hong Kong and to mink in farm outbreaks highlight for the control of COVID-19 and emerging infectious disease, the One Health approach is critical in understanding and accounting for how human, animals and environment health are intricately connected.