Uses of Immune Globulins in the Prophylaxis and Treatment of Viral Infections

SARS-CoV-2 variants inactivation of plasma units using a riboflavin and ultraviolet light-based photochemical treatment

Background

Test the ability of Mirasol Pathogen Reduction Technology (PRT, Terumo BCT, Lakewood Co, USA) treatment with riboflavin and ultraviolet light (R + UV) in reducing SARS-CoV-2 infectivity while maintaining blood product quality.

Material and methods

SARS-CoV-2 strains were isolated and titrated to prepare cell free virus for plasma units infection. The units were then under treatment with Mirasol PRT. The infectious titers were determined before and after treatment with an in house microtitration assay on Vero E6 cells. Thirty-six plasma pool bags underwent PRT treatment.

Results

In all the experiments, the measured titer following riboflavin and UV treatment was below the limit of detection of microtitration assay for all the different SARS-CoV-2 strains. Despite the high copies number detected by RT-PCR for each viral strain after treatment, viruses were completely inactivated and not able to infect VERO E6 cells.

Conclusion

Riboflavin and UV light treatment effectively reduced the virus titers of human plasma to the limit of detection in tissue culture, regardless of the strain. These data suggest that pathogen reduction in blood products highlight the safety of CP therapy procedures for critically ill COVID-19 patients, while maintaining blood product quality.

Preparedness and activities of the anti-SARS-CoV-2 convalescent plasma bank in the Veneto region (Italy): An organizational model for future emergencies

Background

Convalescent plasma (CP) has been used in the past in various pandemics, in particular in H1N1, SARS and MERS infections. In Spring 2020, when ongoing the SARS-CoV-2 pandemics, the Veneto Region (V-R) has proposed setting-up an anti-SARS-CoV-2 CP (CCP) Bank, with the aim of preparing a supply of CCP immediately available in case of subsequest epidemic waves.

Materials and Methods

Key-points to be developed for a quick set-up of the V-R CCP Bank have been recruitment of donors recovered from COVID-19 infection, laboratory analysis for the biological qualification of the CCP units, including titre of neutralizing antibodies and reduction of pathogens, according to National Blood Centre (CNS) Directives, adaptation of the V-R Information Technology systems and cost analysis. Some activities, including diagnostic and viral inactivation processes, have been centralized in 2 or 3 sites. Laboratory analysis upon preliminary admission of the donor included all tests required by the Italian laws and the CNS directives.

Results

From April to August 2020, 3,298 people have contacted the V-R Blood Transfusion Services: of these, 1,632 have been evaluated and examined as first time donors and those found to be suitable have carried out 955 donations, from which 2,626 therapeutic fractions have been obtained, at a cost around 215,00 Euro. Since October 2020, the number of COVID-19 inpatients has had a surge with a heavy hospital overload. Moreover, the high request of CCP therapy by clinicians has been just as unexpected, showing a wide therapeutic use.

Conclusions

The organizational model here presented, which has allowed the rapid collection of a large amount of CCP, could be useful when facing new pandemic outbreaks, especially in low and middle income countries, with generally acceptable costs.