Regulatory consideration on preparation and clinical use of COVID-19 convalescent plasma.

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the cause of coronavirus disease (COVID-19), spreading from Wuhan to worldwide has been emerged since December 2019. Although scientists and researchers have been racing to develop specific therapeutic agents or vaccines against SARS-CoV-2 since the identification of the agent, either a drug or a vaccine has not been approved to treat or to prevent COVID-19 up to date. On the base of historical experiences, Convalescent Plasma (CP), a passive antibody therapy, has been evaluated as a hopeful and potential therapeutic option since the beginning of the COVID-19 outbreak. Immune plasma had been used previously for the treatment of H1N1 influenza virus, SARS-CoV-1 and MERS-CoV epidemics successfully. In this scope competent authorities are responsible to set up certain principles and criteria for the collection and clinical use of COVID-19 Convalescent Plasma (CCP). This document has been prepared to aid both for the convalescent plasma suppliers and the clinicians. The first part encompasses the supply of CCP and the second part lead the clinical use of CCP for the treatment of patients with severe COVID-19 infection. Turkish Ministry of Health developed a guide on collection and clinical use of CCP and created a web-based monitoring system to follow-up the patients treated with convalescent plasma in universal. This follow-up process is thought to be crucial for the creation and development of current and future treatment modalities. This guide would be a pathfinder for clinicians and/or institutions those eager to conduct CCP treatment more effectively.

In vitro efficacy of frozen erythrocytes: implementation of new strategic blood stores to alleviate resource shortage (issue revisited).

BACKGROUND/AIM: Currently, the provision of blood products largely depends on walking blood banks and limited amounts of stored blood with short shelf lives. We aimed to compare the efficacy of erythrocyte concentrate (ECs) by pre- and postfreezing in vitro tests. MATERIALS AND METHODS: In our study, 10 ECs were glycerolized, frozen, thawed, and then deglycerolized using the Naval Blood Research Laboratory method. In addition to using the standard tests, ATP and 2,3-DPG levels and the viability of erythrocytes were also determined. RESULTS: The prefreezing mean viability rates of erythrocytes changed from 89.7 ± 13.7% to 98.6 ± 1.8% after thawing and deglycerolization. Prefreezing and day 0 ATP levels (1.64 ± 0.15 µmol/g Hb and 1.81 ± 0.14 µmol/g Hb, respectively) were similar. The 2,3-DPG levels decreased from 18.09 ± 4.78 µmol/g Hb measured before the procedure to 10.41 ± 4.58 µmol/g Hb on day 0. The mean hemolysis rates and supernatant Hb levels changed from 0.21 ± 0.11% to 0.36 ± 0.12% and 1 ± 0.5 g/L to 1.5 ± 0.5 g/L, respectively. CONCLUSION: The test results showed the efficacy of the frozen-thawed ECs to be used in humans for a broad spectrum of clinical indications. As a part of a contingency plan, national frozen blood reserves need to be established.

Identification of XRCC1 Arg399Gln and XRCC3 Thr241Met Polymorphisms in a Turkish Population and Their Association with the Risk of Chronic Lymphocytic Leukemia.

DNA repair systems are essential for cellular functions. Defects due to sequence variations in DNA repair genes can lead severe failure of cell functions and causing many cancer types including leukemia. The aim of this study was to investigate the relationship between XRCC1 Arg399Gln and XRCC3 Thr241Met polymorphisms and susceptibility to chronic lymphocytic leukemia (CLL) in Turkish patients. In addition, genotype distribution of these polymorphisms was compared with other populations. The frequencies of Arg399Gln and Thr241Met single nucleotide polymorphisms were studied in 25 CLL patients and 30 healthy individuals. Single nucleotide polymorphisms were genotyped by PCR-RFLP method. The genotype and allele frequencies of Arg399Gln and Thr241Met polymorphisms were not statistically different between the CLL patients and control group. The allelic frequency similarities were found between Turkish and Brazilian populations for Arg399Gln polymorphism. On the other hand, similarities were found between Turkish and other Caucasian populations for Thr241Met polymorphism. Marked differences were observed between American African versus Turkish and Chinese versus Turkish populations for Arg399Gln and Thr241Met polymorphisms respectively. These results indicate that Arg399Gln and Thr241Met polymorphisms were not associated with the development of CLL in Turkish population and ethnic differences is one of the most important factor for allele frequency differences.