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1.
Clin Infect Dis ; 74(2): 327-334, 2022 01 29.
Article in English | MEDLINE | ID: covidwho-1662105

ABSTRACT

Convalescent plasma (CP) have been used for treatment of coronavirus disease 2019 (COVID-19), but their effectiveness varies significantly. Moreover, the impact of CP treatment on the composition of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies in COVID-19 patients and antibody markers that differentiate between those who survive and those who succumb to the COVID-19 disease are not well understood. Herein, we performed longitudinal analysis of antibody profile on 115 sequential plasma samples from 16 hospitalized COVID-19 patients treated with either CP or standard of care, only half of them survived. Differential antibody kinetics was observed for antibody binding, immunoglobulin M/immunoglobulin G/immunoglobulin A (IgM/IgG/IgA) distribution, and affinity maturation in "survived" versus "fatal" COVID-19 patients. Surprisingly, CP treatment did not predict survival. Strikingly, marked decline in neutralization titers was observed in the fatal patients prior to death, and convalescent plasma treatment did not reverse this trend. Furthermore, irrespective of CP treatment, higher antibody affinity to the SARS-CoV-2 prefusion spike was associated with survival outcome. Additionally, sustained elevated IgA response was associated with fatal outcome in these COVID-19 patients. These findings propose that treatment of COVID-19 patients with convalescent plasma should be carefully targeted, and effectiveness of treatment may depend on the clinical and immunological status of COVID-19 patients, as well as the quality of the antibodies in the convalescent plasma.


Subject(s)
COVID-19 , SARS-CoV-2 , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/therapy , Humans , Immunization, Passive
2.
Vox Sang ; 116(10): 1076-1083, 2021 Nov.
Article in English | MEDLINE | ID: covidwho-1515248

ABSTRACT

BACKGROUND AND OBJECTIVES: Convalescent plasma (CP) has been embraced as a safe therapeutic option for coronavirus disease 2019 (COVID-19), while other treatments are developed. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is not transmissible by transfusion, but bloodborne pathogens remain a risk in regions with high endemic prevalence of disease. Pathogen reduction can mitigate this risk; thus, the objective of this study was to evaluate the effect of riboflavin and ultraviolet light (R + UV) pathogen reduction technology on the functional properties of COVID-19 CP (CCP). MATERIALS AND METHODS: COVID-19 convalescent plasma units (n = 6) from recovered COVID-19 research donors were treated with R + UV. Pre- and post-treatment samples were tested for coagulation factor and immunoglobulin retention. Antibody binding to spike protein receptor-binding domain (RBD), S1 and S2 epitopes of SARS-CoV-2 was assessed by ELISA. Neutralizing antibody (nAb) function was assessed by pseudovirus reporter viral particle neutralization (RVPN) assay and plaque reduction neutralization test (PRNT). RESULTS: Mean retention of coagulation factors was ≥70%, while retention of immunoglobulins was 100%. Starting nAb titres were low, but PRNT50 titres did not differ between pre- and post-treatment samples. No statistically significant differences were detected in levels of IgG (P ≥ 0·3665) and IgM (P ≥ 0·1208) antibodies to RBD, S1 and S2 proteins before and after treatment. CONCLUSION: R + UV PRT effects on coagulation factors were similar to previous reports, but no significant effects were observed on immunoglobulin concentration and antibody function. SARS-CoV-2 nAb function in CCP is conserved following R + UV PRT treatment.


Subject(s)
Antibodies, Neutralizing , COVID-19 , Antibodies, Viral , COVID-19/therapy , Humans , Immunization, Passive , Riboflavin , SARS-CoV-2 , Technology , Ultraviolet Rays
3.
PLoS Pathog ; 17(1): e1009161, 2021 01.
Article in English | MEDLINE | ID: covidwho-1388959

ABSTRACT

We report the emergency development and application of a robust serologic test to evaluate acute and convalescent antibody responses to SARS-CoV-2 in Argentina. The assays, COVIDAR IgG and IgM, which were produced and provided for free to health authorities, private and public health institutions and nursing homes, use a combination of a trimer stabilized spike protein and the receptor binding domain (RBD) in a single enzyme-linked immunosorbent assay (ELISA) plate. Over half million tests have already been distributed to detect and quantify antibodies for multiple purposes, including assessment of immune responses in hospitalized patients and large seroprevalence studies in neighborhoods, slums and health care workers, which resulted in a powerful tool for asymptomatic detection and policy making in the country. Analysis of antibody levels and longitudinal studies of symptomatic and asymptomatic SARS-CoV-2 infections in over one thousand patient samples provided insightful information about IgM and IgG seroconversion time and kinetics, and IgM waning profiles. At least 35% of patients showed seroconversion within 7 days, and 95% within 45 days of symptoms onset, with simultaneous or close sequential IgM and IgG detection. Longitudinal studies of asymptomatic cases showed a wide range of antibody responses with median levels below those observed in symptomatic patients. Regarding convalescent plasma applications, a protocol was standardized for the assessment of end point IgG antibody titers with COVIDAR with more than 500 plasma donors. The protocol showed a positive correlation with neutralizing antibody titers, and was used for clinical trials and therapies across the country. Using this protocol, about 80% of convalescent donor plasmas were potentially suitable for therapies. Here, we demonstrate the importance of providing a robust and specific serologic assay for generating new information about antibody kinetics in infected individuals and mitigation policies to cope with pandemic needs.


Subject(s)
COVID-19/virology , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Adult , Aged , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , Antibody Formation , Argentina/epidemiology , COVID-19/epidemiology , Enzyme-Linked Immunosorbent Assay/methods , Female , Humans , Immunoglobulin G/immunology , Immunoglobulin M/immunology , Longitudinal Studies , Male , Middle Aged , Pandemics , SARS-CoV-2/isolation & purification , Seroepidemiologic Studies
4.
Hemodial Int ; 25(4): 515-522, 2021 10.
Article in English | MEDLINE | ID: covidwho-1270837

ABSTRACT

BACKGROUND: The passive immunization of patients with SARS-CoV2 with convalescent plasma (CP) is theoretically beneficial in patients with end-stage renal disease who are immunosuppressed and unable to mount an adequate immune response. Hence, this study was conducted to evaluate the safety and efficacy of CP in patients with chronic kidney disease on hemodialysis with moderate-to-severe SARS-CoV2 infection. METHODS: A prospective observational cohort study was conducted in consecutive 68 moderate-to-severe SARS-CoV2 infected patients who were on maintenance hemodialysis or with acute worsening of chronic kidney disease which required initiation of hemodialysis. Patients who received CP were compared with those who did not. The primary outcome was death during hospitalization. Clinical characteristics, duration of hospitalization and inflammatory parameters were compared between the two groups. A subgroup analysis was done to find whether early initiation of plasma was associated with better outcome. RESULTS: Sixteen patients (44%) in the plasma group and 14 (45%) patients in the control group died during hospitalization (p = 0.95). The median duration of hospitalization was 9 (6-14) days in the plasma group and 9 (6-16) in the control group (p = 0.60). There was no difference in mortality or duration of hospitalization with respect to early initiation of CP (p = 0.29). Fistula thrombosis occurred in two patients (11.1%) in the plasma group. CONCLUSION: Therapy with CP does not appear to confer any clinical benefit in moderate-to-severe SARS-CoV-2 infected patients with chronic kidney disease on hemodialysis.


Subject(s)
COVID-19 , RNA, Viral , COVID-19/therapy , Humans , Immunization, Passive , Prospective Studies , Renal Dialysis/adverse effects , SARS-CoV-2 , Treatment Outcome
5.
Arch Pathol Lab Med ; 145(10): 1221-1227, 2021 10 01.
Article in English | MEDLINE | ID: covidwho-1261421

ABSTRACT

CONTEXT.­: The ongoing COVID-19 pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has elicited a surge in demand for serologic testing to identify previously infected individuals. In particular, antibody testing is crucial in identifying COVID-19 convalescent plasma, which has been approved by the Food and Drug Administration under the Emergency Use Authorization for use as passive immunotherapy for hospitalized patients infected with COVID-19. Currently, high-titer COVID-19 convalescent plasma can be qualified by Ortho's Vitros COVID-19 IgG antibody test. OBJECTIVE.­: To explore the use of an efficient testing method to identify high-titer COVID-19 convalescent plasma for use in treating COVID-19-infected patients and track COVID-19 positivity over time. DESIGN.­: We evaluated an enzyme-linked immunosorbent assay (ELISA)-based method that detects antibodies specific to the SARS-CoV-2 receptor binding domain (RBD) with individual and pooled plasma samples and compared its performance against the Vitros COVID-19 IgG antibody test. Using the pooled RBD-ELISA (P-RE) method, we also screened more than 10 000 longitudinal healthy blood donor samples to assess seroprevalence. RESULTS.­: P-RE demonstrates 100% sensitivity in detecting Food and Drug Administration-defined high-titer samples when compared with the Vitros COVID-19 IgG antibody test. Overall sensitivity of P-RE when compared with the Vitros COVID-19 IgG antibody test and our individual sample RBD-ELISA (I-RE) were 83% and 56%, respectively. When screening 10 218 healthy blood donor samples by P-RE, we found the seroprevalence correlated with the local infection rates with a correlation coefficient of 0.21 (P < .001). CONCLUSIONS.­: Pooling plasma samples can be used to efficiently screen large populations for individuals with high-titer anti-RBD antibodies, important for COVID-19 convalescent plasma identification.


Subject(s)
Antibodies, Viral/immunology , COVID-19 Serological Testing/methods , COVID-19/diagnosis , Enzyme-Linked Immunosorbent Assay/methods , Immunoglobulin G/immunology , SARS-CoV-2/immunology , Antibodies, Viral/blood , Blood Donors/statistics & numerical data , COVID-19/epidemiology , COVID-19/virology , Humans , Immunoglobulin G/blood , Pandemics/prevention & control , Reproducibility of Results , SARS-CoV-2/physiology , Sensitivity and Specificity , Seroepidemiologic Studies
6.
Nat Commun ; 12(1): 3189, 2021 05 27.
Article in English | MEDLINE | ID: covidwho-1246368

ABSTRACT

In a randomized clinical trial of 86 hospitalized COVID-19 patients comparing standard care to treatment with 300mL convalescent plasma containing high titers of neutralizing SARS-CoV-2 antibodies, no overall clinical benefit was observed. Using a comprehensive translational approach, we unravel the virological and immunological responses following treatment to disentangle which COVID-19 patients may benefit and should be the focus of future studies. Convalescent plasma is safe, does not improve survival, has no effect on the disease course, nor does plasma enhance viral clearance in the respiratory tract, influence SARS-CoV-2 antibody development or serum proinflammatory cytokines levels. Here, we show that the vast majority of patients already had potent neutralizing SARS-CoV-2 antibodies at hospital admission and with comparable titers to carefully selected plasma donors. This resulted in the decision to terminate the trial prematurely. Treatment with convalescent plasma should be studied early in the disease course or at least preceding autologous humoral response development.


Subject(s)
Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19/immunology , COVID-19/therapy , Cytokines/blood , SARS-CoV-2/immunology , Aged , Antibodies, Neutralizing/blood , Antibodies, Viral/blood , Blood Donors , COVID-19/blood , COVID-19/virology , Disease Progression , Female , Hospitalization , Humans , Immunization, Passive , Immunoglobulin G/blood , Kaplan-Meier Estimate , Male , Middle Aged , Spike Glycoprotein, Coronavirus/immunology , Treatment Outcome
8.
Front Immunol ; 12: 675679, 2021.
Article in English | MEDLINE | ID: covidwho-1231340

ABSTRACT

Background: COVID-19 Convalescent plasma (CCP) is safe and effective, particularly if given at an early stage of the disease. Our study aimed to identify an association between survival and specific antibodies found in CCP. Patients and Methods: Patients ≥18 years of age who were hospitalized with moderate to severe COVID-19 infection and received CCP at the MD Anderson Cancer Center between 4/30/2020 and 8/20/2020 were included in the study. We quantified the levels of anti-SARS-CoV-2 antibodies, as well as antibodies against antigens of other coronavirus strains, in the CCP units and compared antibody levels with patient outcomes. For each antibody, a Bayesian exponential survival time regression model including prognostic variables was fit, and the posterior probability of a beneficial effect (PBE) of higher antibody level on survival time was computed. Results: CCP was administered to 44 cancer patients. The median age was 60 years (range 37-84) and 19 (43%) were female. Twelve patients (27%) died of COVID-19-related complications. Higher levels of two non-SARS-CoV-2-specific antibodies, anti-HCoV-OC43 spike IgG and anti-HCoV-HKU1 spike IgG, had PBE = 1.00, and 4 SARS-CoV-2-specific antibodies had PBEs between 0.90 and 0.95. Other factors associated with better survival were shorter time to CCP administration, younger age, and female sex. Conclusions: Common cold coronavirus spike IgG antibodies anti-HCoV-OC43 and anti-HCoV-HKU1 may target a common domain for SARS-CoV-2 and other coronaviruses. They provide a promising therapeutic target for monoclonal antibody production.


Subject(s)
Antibodies, Viral , Betacoronavirus/immunology , COVID-19/therapy , Common Cold/immunology , Convalescence , Coronavirus OC43, Human/immunology , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Adult , Aged , Aged, 80 and over , Antibodies, Viral/administration & dosage , Antibodies, Viral/immunology , COVID-19/immunology , COVID-19/mortality , Cross Reactions , Female , Humans , Immunization, Passive , Male , Middle Aged
9.
PLoS One ; 16(5): e0251262, 2021.
Article in English | MEDLINE | ID: covidwho-1221859

ABSTRACT

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic overwhelmed healthcare systems, highlighting the need to better understand predictors of mortality and the impact of medical interventions. METHODS: This retrospective cohort study examined data from every patient who tested positive for COVID-19 and was admitted to White Plains Hospital between March 9, 2020, and June 3, 2020. We used binomial logistic regression to analyze data for all patients, and propensity score matching for those treated with hydroxychloroquine and convalescent plasma (CP). The primary outcome of interest was inpatient mortality. RESULTS: 1,108 admitted patients with COVID-19 were available for analysis, of which 124 (11.2%) were excluded due to incomplete data. Of the 984 patients included, 225 (22.9%) died. Risk for death decreased for each day later a patient was admitted [OR 0.970, CI 0.955 to 0.985; p < 0.001]. Elevated initial C-reactive protein (CRP) value was associated with a higher risk for death at 96 hours [OR 1.007, 1.002 to 1.012; p = 0.006]. Hydroxychloroquine and CP administration were each associated with increased mortality [OR 3.4, CI 1.614 to 7.396; p = 0.002, OR 2.8560, CI 1.361 to 6.160; p = 0.006 respectively]. CONCLUSIONS: Elevated CRP carried significant odds of early death. Hydroxychloroquine and CP were each associated with higher risk for death, although CP was without titers and was administered at a median of five days from admission. Randomized or controlled studies will better describe the impact of CP. Mortality decreased as the pandemic progressed, suggesting that institutional capacity for dynamic evaluation of process and outcome measures may benefit COVID-19 survival.


Subject(s)
COVID-19/mortality , Hospital Mortality , Adult , Aged , Aged, 80 and over , Antiviral Agents/therapeutic use , C-Reactive Protein/analysis , COVID-19/drug therapy , COVID-19/pathology , COVID-19/virology , Female , Hospitalization/statistics & numerical data , Humans , Hydroxychloroquine/therapeutic use , Logistic Models , Male , Middle Aged , Odds Ratio , Outcome Assessment, Health Care , Retrospective Studies , Risk , SARS-CoV-2/isolation & purification , Young Adult
10.
mBio ; 12(2)2021 04 20.
Article in English | MEDLINE | ID: covidwho-1195826

ABSTRACT

Convalescent plasma is a promising therapy for coronavirus disease 2019 (COVID-19), but the antibody characteristics that contribute to efficacy remain poorly understood. This study analyzed plasma samples from 126 eligible convalescent blood donors in addition to 15 naive individuals, as well as an additional 20 convalescent individuals as a validation cohort. Multiplexed Fc Array binding assays and functional antibody response assays were utilized to evaluate severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibody composition and activity. Donor convalescent plasma samples contained a range of antibody cell- and complement-mediated effector functions, indicating the diverse antiviral activity of humoral responses observed among recovered individuals. In addition to viral neutralization, convalescent plasma samples contained antibodies capable of mediating such Fc-dependent functions as complement activation, phagocytosis, and antibody-dependent cellular cytotoxicity against SARS-CoV-2. Plasma samples from a fraction of eligible donors exhibited high activity across all activities evaluated. These polyfunctional plasma samples could be identified with high accuracy with even single Fc Array features, whose correlation with polyfunctional activity was confirmed in the validation cohort. Collectively, these results expand understanding of the diversity of antibody-mediated antiviral functions associated with convalescent plasma, and the polyfunctional antiviral functions suggest that it could retain activity even when its neutralizing capacity is reduced by mutations in variant SARS-CoV-2.IMPORTANCE Convalescent plasma has been deployed globally as a treatment for COVID-19, but efficacy has been mixed. Better understanding of the antibody characteristics that may contribute to its antiviral effects is important for this intervention as well as offer insights into correlates of vaccine-mediated protection. Here, a survey of convalescent plasma activities, including antibody neutralization and diverse effector functions, was used to define plasma samples with broad activity profiles. These polyfunctional plasma samples could be reliably identified in multiple cohorts by multiplex assay, presenting a widely deployable screening test for plasma selection and investigation of vaccine-elicited responses.


Subject(s)
Antibodies, Viral/blood , COVID-19/immunology , COVID-19/therapy , SARS-CoV-2/immunology , Adult , Aged , Antibodies, Neutralizing/blood , Antibody Specificity , Antibody-Dependent Cell Cytotoxicity , Antigens, Viral/immunology , Biophysical Phenomena , Cohort Studies , Complement Activation , Convalescence , Female , Humans , Immunization, Passive , Male , Middle Aged , Phagocytosis , Young Adult
12.
Clin Infect Dis ; 74(2): 327-334, 2022 01 29.
Article in English | MEDLINE | ID: covidwho-1189441

ABSTRACT

Convalescent plasma (CP) have been used for treatment of coronavirus disease 2019 (COVID-19), but their effectiveness varies significantly. Moreover, the impact of CP treatment on the composition of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies in COVID-19 patients and antibody markers that differentiate between those who survive and those who succumb to the COVID-19 disease are not well understood. Herein, we performed longitudinal analysis of antibody profile on 115 sequential plasma samples from 16 hospitalized COVID-19 patients treated with either CP or standard of care, only half of them survived. Differential antibody kinetics was observed for antibody binding, immunoglobulin M/immunoglobulin G/immunoglobulin A (IgM/IgG/IgA) distribution, and affinity maturation in "survived" versus "fatal" COVID-19 patients. Surprisingly, CP treatment did not predict survival. Strikingly, marked decline in neutralization titers was observed in the fatal patients prior to death, and convalescent plasma treatment did not reverse this trend. Furthermore, irrespective of CP treatment, higher antibody affinity to the SARS-CoV-2 prefusion spike was associated with survival outcome. Additionally, sustained elevated IgA response was associated with fatal outcome in these COVID-19 patients. These findings propose that treatment of COVID-19 patients with convalescent plasma should be carefully targeted, and effectiveness of treatment may depend on the clinical and immunological status of COVID-19 patients, as well as the quality of the antibodies in the convalescent plasma.


Subject(s)
COVID-19 , SARS-CoV-2 , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/therapy , Humans , Immunization, Passive
13.
Vox Sang ; 116(10): 1076-1083, 2021 Nov.
Article in English | MEDLINE | ID: covidwho-1175120

ABSTRACT

BACKGROUND AND OBJECTIVES: Convalescent plasma (CP) has been embraced as a safe therapeutic option for coronavirus disease 2019 (COVID-19), while other treatments are developed. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is not transmissible by transfusion, but bloodborne pathogens remain a risk in regions with high endemic prevalence of disease. Pathogen reduction can mitigate this risk; thus, the objective of this study was to evaluate the effect of riboflavin and ultraviolet light (R + UV) pathogen reduction technology on the functional properties of COVID-19 CP (CCP). MATERIALS AND METHODS: COVID-19 convalescent plasma units (n = 6) from recovered COVID-19 research donors were treated with R + UV. Pre- and post-treatment samples were tested for coagulation factor and immunoglobulin retention. Antibody binding to spike protein receptor-binding domain (RBD), S1 and S2 epitopes of SARS-CoV-2 was assessed by ELISA. Neutralizing antibody (nAb) function was assessed by pseudovirus reporter viral particle neutralization (RVPN) assay and plaque reduction neutralization test (PRNT). RESULTS: Mean retention of coagulation factors was ≥70%, while retention of immunoglobulins was 100%. Starting nAb titres were low, but PRNT50 titres did not differ between pre- and post-treatment samples. No statistically significant differences were detected in levels of IgG (P ≥ 0·3665) and IgM (P ≥ 0·1208) antibodies to RBD, S1 and S2 proteins before and after treatment. CONCLUSION: R + UV PRT effects on coagulation factors were similar to previous reports, but no significant effects were observed on immunoglobulin concentration and antibody function. SARS-CoV-2 nAb function in CCP is conserved following R + UV PRT treatment.


Subject(s)
Antibodies, Neutralizing , COVID-19 , Antibodies, Viral , COVID-19/therapy , Humans , Immunization, Passive , Riboflavin , SARS-CoV-2 , Technology , Ultraviolet Rays
14.
Clin Immunol ; 227: 108723, 2021 06.
Article in English | MEDLINE | ID: covidwho-1171785

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 infected patients, receiving background anti-CD20 therapy, were treated with convalescent plasma or plasma-based products. Eight patients were included in the study, presenting with prolonged disease course and delayed viral clearance. CP/plasma-based products were offered as an add-on therapy to standard medical treatment. All patients showed remarkable clinical and laboratory improvement. In addition, polymerase chain reaction from nasopharyngeal swabs rapidly converted to negative following plasma administration. This study emphasizes the therapeutic efficacy of convalescent plasma and plasma-based products in a subgroup of immunocompromised patients with iatrogenic B-cell depletion.


Subject(s)
B-Lymphocytes/immunology , COVID-19/drug therapy , COVID-19/immunology , COVID-19/therapy , Immunocompromised Host/drug effects , SARS-CoV-2/drug effects , Antibodies, Viral/blood , Antineoplastic Agents, Immunological/administration & dosage , COVID-19/physiopathology , Female , Humans , Immunization, Passive/methods , Male , Middle Aged , Rituximab/administration & dosage , Treatment Outcome
15.
Vox Sang ; 116(6): 665-672, 2021 Jul.
Article in English | MEDLINE | ID: covidwho-1140312

ABSTRACT

BACKGROUND AND OBJECTIVES: COVID-19 convalescent plasma is an experimental treatment against SARS-CoV-2. The aim of this study is to assess the impact of different pathogen reduction methods on the levels and virus neutralizing activity of the specific antibodies against SARS-CoV2 in convalescent plasma. MATERIALS AND METHODS: A total of 140 plasma doses collected by plasmapheresis from COVID-19 convalescent donors were subjected to pathogen reduction by three methods: methylene blue (M)/visible light, riboflavin (R)/UVB and amotosalen (A)/UVA. To conduct a paired comparison, individual plasma doses were divided into 2 samples that were subjected to one of these methods. The titres of SARS-CoV2 neutralizing antibodies (NtAbs) and levels of specific immunoglobulins to RBD, S- and N-proteins of SARS-CoV-2 were measured before and after pathogen reduction. RESULTS: The methods reduced NtAbs titres differently: among units with the initial titre 80 or above, 81% of units remained unchanged and 19% decreased by one step after methylene blue; 60% were unchanged and 40% decreased by one step after amotosalen; after riboflavin 43% were unchanged and 50% (7%, respectively) had a one-step (two-step, respectively) decrease. Paired two-sample comparisons (M vs. A, M vs. R and A vs. R) revealed that the largest statistically significant decrease in quantity and activity of the specific antibodies resulted from the riboflavin treatment. CONCLUSION: Pathogen reduction with methylene blue or with amotosalen provides the greater likelihood of preserving the immunological properties of the COVID-19 convalescent plasma compared to riboflavin.


Subject(s)
Blood Safety/methods , Blood-Borne Pathogens/isolation & purification , COVID-19/therapy , Plasma/immunology , Antibodies, Neutralizing/blood , COVID-19/immunology , Furocoumarins , Humans , Immunization, Passive , Methylene Blue , Riboflavin , SARS-CoV-2/immunology
16.
J Clin Microbiol ; 59(3)2021 02 18.
Article in English | MEDLINE | ID: covidwho-1133128

ABSTRACT

As the coronavirus disease 2019 (COVID-19) pandemic second wave is emerging, it is of the upmost importance to screen the population immunity in order to keep track of infected individuals. Consequently, immunoassays for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with high specificity and positive predictive values are needed to obtain an accurate epidemiological picture. As more data accumulate about the immune responses and the kinetics of neutralizing-antibody (nAb) production in SARS-CoV-2-infected individuals, new applications are forecast for serological assays such as nAb activity prediction in convalescent-phase plasma from recovered patients. This multicenter study, involving six hospital centers, determined the baseline clinical performances, reproducibility, and nAb level correlations of 10 commercially available immunoassays. In addition, three lateral-flow chromatography assays were evaluated, as these devices can be used in logistically challenged areas. All assays were evaluated using the same patient panels in duplicate, thus enabling accurate comparison of the tests. Seven immunoassays examined in this study were shown to have excellent specificity (98 to 100%) and good to excellent positive predictive values (82 to 100%) when used in a low (5%)-seroprevalence setting. We observed sensitivities as low as 74% and as high as 95% at ≥15 days after symptom onset. The determination of optimized cutoff values through receiver operating characteristic (ROC) curve analyses had a significant impact on the diagnostic resolution of several enzyme immunoassays by increasing the sensitivity significantly without a large trade-off in specificity. We found that spike-based immunoassays seem to be better correlates of nAb activity. Finally, the results reported here will add to the general knowledge of the interlaboratory reproducibility of clinical performance parameters of immunoassays and provide new evidence about nAb activity prediction.


Subject(s)
Antibodies, Neutralizing/analysis , Antibodies, Viral/analysis , COVID-19/diagnosis , High-Throughput Screening Assays/standards , COVID-19/immunology , Humans , Laboratories , Reproducibility of Results , SARS-CoV-2 , Sensitivity and Specificity , Seroepidemiologic Studies
17.
Trials ; 22(1): 199, 2021 Mar 09.
Article in English | MEDLINE | ID: covidwho-1127723

ABSTRACT

BACKGROUND: Early inhibition of entry and replication of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a very promising therapeutic approach. Polyclonal neutralizing antibodies offers many advantages such as providing immediate immunity, consequently blunting an early pro-inflammatory pathogenic endogenous antibody response and lack of drug-drug interactions. By providing immediate immunity and inhibiting entry into cells, neutralizing antibody treatment is of interest for patient with COVID-19-induced moderate pneumonia. Convalescent plasma to treat infected patients is therefore a relevant therapeutic option currently under assessment (CORIMUNO-PLASM NCT04324047). However, the difficulties of collecting plasma on the long term are not adapted to a broad use across all populations. New polyclonal humanized anti-SARS-CoV2 antibodies (XAV-19) developed by Xenothera and administered intravenous. XAV-19 is a heterologous swine glyco-humanized polyclonal antibody (GH-pAb) raised against the spike protein of SARS-CoV-2, blocking infection of ACE-2-positive human cells with SARS-CoV-2. METHODS: Pharmacokinetic and pharmacodynamic studies have been performed in preclinical models including primates. A first human study with another fully representative GH-pAb from Xenothera is ongoing in recipients of a kidney graft. These studies indicated that 5 consecutive administrations of GH-pAbs can be safely performed in humans. The objectives of this 2-step phase 2 randomized double-blinded, placebo-controlled study are to define the safety and the optimal XAV-19 dose to administrate to patients with SARS-CoV-2 induced moderate pneumonia, and to assess the clinical benefits of a selected dose of XAV-19 in this population. DISCUSSION: This study will determine the clinical benefits of XAV-19 when administered to patients with SARS-CoV-2-induced moderate pneumonia. As a prerequisite, a first step of the study will define the safety and the dose of XAV-19 to be used. Such treatment might become a new therapeutic option to provide an effective treatment for COVID-19 patients (possibly in combination with anti-viral and immunotherapies). Further studies could later evaluate such passive immunotherapy as a potential post-exposure prophylaxis. TRIAL REGISTRATION: ClinicalTrials.gov NCT04453384 , registered on 1 July 2020, and EUDRACT 2020-002574-27, registered 6 June 2020.


Subject(s)
Antibodies, Neutralizing/therapeutic use , COVID-19/therapy , Immunoglobulin G/therapeutic use , Animals , Antibodies, Monoclonal, Humanized , Clinical Trials, Phase II as Topic , Double-Blind Method , Humans , Immunization, Passive , Oxygen Inhalation Therapy , Randomized Controlled Trials as Topic , SARS-CoV-2/immunology , Severity of Illness Index , Spike Glycoprotein, Coronavirus/immunology , Swine , Time Factors
18.
Sci Rep ; 11(1): 5558, 2021 03 10.
Article in English | MEDLINE | ID: covidwho-1125779

ABSTRACT

The recent COVID-19 pandemic poses a serious threat to global public health, thus there is an urgent need to define the molecular mechanisms involved in SARS-CoV-2 spike (S) protein-mediated virus entry that is essential for preventing and/or treating this emerging infectious disease. In this study, we examined the blocking activity of human COVID-19 convalescent plasma by cell-cell fusion assays using SARS-CoV-2-S-transfected 293 T as effector cells and ACE2-expressing 293 T as target cells. We demonstrate that the SARS-CoV-2 S protein exhibits a very high capacity for membrane fusion and is efficient in mediating virus fusion and entry into target cells. Importantly, we find that COVID-19 convalescent plasma with high titers of IgG neutralizing antibodies can block cell-cell fusion and virus entry by interfering with the SARS-CoV-2-S/ACE2 or SARS-CoV-S/ACE2 interactions. These findings suggest that COVID-19 convalescent plasma may not only inhibit SARS-CoV-2-S but also cross-neutralize SARS-CoV-S-mediated membrane fusion and virus entry, supporting its potential as a preventive and/or therapeutic agent against SARS-CoV-2 as well as other SARS-CoV infections.


Subject(s)
COVID-19/immunology , COVID-19/therapy , Spike Glycoprotein, Coronavirus/immunology , Adult , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19/prevention & control , Cell Fusion/methods , Female , Humans , Immunization, Passive/methods , Male , Membrane Fusion/drug effects , Middle Aged , Pandemics/prevention & control , Plasma/chemistry , Receptors, Virus/metabolism , SARS-CoV-2/immunology , SARS-CoV-2/pathogenicity , Spike Glycoprotein, Coronavirus/metabolism , Virus Internalization/drug effects
20.
Transfusion ; 61(5): 1377-1382, 2021 05.
Article in English | MEDLINE | ID: covidwho-1088172

ABSTRACT

BACKGROUND: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus is the cause of the ongoing coronavirus disease 2019 (COVID-19) pandemic, infecting millions of people and causing more than two million deaths. The SARS-CoV-2 Spike glycoproteins mediate viral entry and represent the main target for antibody responses. Humoral responses were shown to be important for preventing and controlling infection by coronaviruses. A promising approach to reduce the severity of COVID-19 is the transfusion of convalescent plasma. However, longitudinal studies revealed that the level of antibodies targeting the receptor-binding domain (RBD) of the SARS-CoV-2 Spike declines rapidly after the resolution of the infection. STUDY DESIGN AND METHODS: To extend this observation beyond the RBD domain, we performed a longitudinal analysis of the persistence of antibodies targeting the full-length SARS-CoV-2 Spike in the plasma from 15 convalescent donors. We generated a 293T cell line constitutively expressing the SARS-CoV-2 Spike and used it to develop a high-throughput flow cytometry-based assay to detect SARS-CoV-2 Spike-specific antibodies in the plasma of convalescent donors. RESULTS AND CONCLUSION: We found that the level of antibodies targeting the full-length SARS-CoV-2 Spike declines gradually after the resolution of the infection. This decline was not related to the number of donations but strongly correlated with the decline of RBD-specific antibodies and the number of days post-symptom onset. These findings help to better understand the decline of humoral responses against the SARS-CoV-2 Spike and provide important information on when to collect plasma after recovery from active infection for convalescent plasma transfusion.


Subject(s)
Antibodies, Viral/blood , COVID-19/blood , SARS-CoV-2/metabolism , Spike Glycoprotein, Coronavirus/blood , COVID-19/therapy , Female , HEK293 Cells , Humans , Immunization, Passive , Longitudinal Studies , Male
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