Characterization of Ebola convalescent plasma donor immune response and psoralen treated plasma in the United States

Abstract

BACKGROUND: In 2014, passive immunization by transfusion of Ebola convalescent plasma (ECP) was considered for treating patients with acute Ebola virus disease (EVD). Early Ebola virus (EBOV) seroconversion confers a survival advantage in natural infection, hence transfusion of ECP plasma with high levels of neutralizing EBOV antibodies is a potential passive immune therapy. Techniques to reduce the risk of other transfusion-transmitted infections (TTIs) are warranted as recent ECP survivors are ineligible as routine blood donors. As part of an ongoing clinical trial to evaluate the safety and effectiveness of ECP, the impact of amotosalen/UVA pathogen reduction technology (PRT) on EBOV antibody characteristics was examined.STUDY DESIGN AND METHODS: Serum and plasma samples were collected from EVD-recovered subjects at multiple timepoints and evaluated by ELISA for antibodies to recombinant EBOV glycoprotein (GP) and irradiated whole EBOV antigen, as well as for EBOV microneutralization, classic plaque reduction neutralization test (PRNT) and EBOV pseudovirion neutralization assay (PsVNA) activity. RESULTS: Six subjects donated 40 individual ECPunits. Substantial antibody titers and neutralizing activity results were demonstrated but were generally lower for the ACD plasma samples compared to the serum samples. Anti-EBOV titers by all assays remained essentially unchanged after PRT.CONCLUSION: Treatment of ECP with PRT to reduce the risk of TTI did not significantly reduce EBOV IgG antibody titers or neutralizing activity. Although ECP was used in the treatment of repatriated patients, no PRT units from this study were transfused to EVD patients. This inventory of PRT-treated ECP is currently available for future clinical evaluation.From the

Convalescent plasma anti–SARS-CoV-2 spike protein ectodomain and receptor-binding domain IgG correlate with virus neutralization

“…A second SARS-CoV-2 microneutralization assay (VN2) was adapted from an assay used to study Ebola virus (38). This assay also used SARS-CoV-2 strain WA1.…”

Relationship between Anti-Spike Protein Antibody Titers and SARS-CoV-2In VitroVirus Neutralization in Convalescent Plasma

“…A second SARS-CoV-2 microneutralization assay (VN2) was adapted from an assay used to study Ebola virus (32). This assay also used SARS-CoV-2 strain WA1.…”

Estudos experimentais sobre COVID-19: panorama da produção científica mundial

“…Os colaboradores eram instituições hospitalares ou universidades com frequência de 40,9% (18) Observou-se que somente 6,8% (44) dos estudos eram classificados como fase 4, ou seja, aqueles que já possuem autorização de introdução no mercado. A maioria estava recrutando (n=16; 36,4%) ou não recrutando participantes (n=22; 50%).…”

“…O uso do plasma convalescente possui histórico positivo no tratamento em outras infecções virais, tais como a influenza pandêmica A (H1N1), influenza aviária A (H5N1) e febres hemorrágicas, como o Ebola. (18) No contexto da pandemia de COVID-19, esse tratamento tem sido testado e série de casos têm mostrado que pacientes com insuficiência respiratória grave, que receberam essa intervenção, apresentaram aumento dos anticorpos neutralizantes e apresentaram melhoras clínicas. (19) No entanto, os estudos disponíveis sobre esse tipo de tratamento possuem baixo nível de evidência e a condução de estudos experimentais que esclareçam seus efeitos se fazem necessários.…”