Presence and quantity of antibodies after vaccination «Gam-COVID-Vac¼.

The determine is to study the presence and quantity of specific antibodies in individuals vaccinated against COVID-19. A study of 37 blood serums of healthy adults vaccinated against COVID-19 with the vaccine «Gam-COVID-Vac¼ (or «Sputnik V¼, National Research Center of Epidemiology and Microbiology named after N.F. Gamalei) was conducted. Blood sampling was carried out 42 days after the introduction of the first component of the vaccine, and 3, 4, 5, 6 months after the end of the full course of vaccination. The presence and quantity of total IgM/IgG antibodies in the blood serum was determined by immunochemiluminescence analysis on an automatic immunochemical analyzer «Cobas e 411¼ («Roche Diagnostics¼, Germany). The results were processed by modern statistical methods. 42 days after the introduction of the first component of the vaccine «Gam-COVID-Vac¼ AT was developed in all study participants, the values of their number were variable and ranged from 36,43 to 265,43 BAU/ ml. 3, 4, 5 and 6 months after the end of the full course of vaccination AT were detected in all study participants. 6 months after the end of the full course of vaccination the number antibodies decreased by 28,16%.

Diagnostic characteristics of serological tests for the detection of SARS-CoV-2 cases.

To study the diagnostic characteristics of test systems for detecting antibodies to SARS-Cov-2. We studied the diagnostic characteristics of two test systems for detecting antibodies to SARS-Cov-2, registered in the Russian Federation. The first test system is a kit for detecting total antibodies to SARS-Cov-2 using immunochemiluminescence analysis on the «Cobas e 411¼ analyzer («Roche Diagnostics¼, Germany). The second test system is a kit for detecting IgM and IgG to SARS-Cov-2 («Core Technology Co., Ltd¼, China) by immunochromatographic analysis. The biological material for the study was blood serum. We assessed: diagnostic sensitivity, diagnostic specificity, and predictive value of positive and negative results. In the test system for detecting total antibodies to SARS-CoV-2, using an IHLA, the diagnostic sensitivity and specificity were 100%; the predictive value of positive and negative results was 100%. In the test system for the detection of IgM and IgG to Sars-CoV-2, using IHA, diagnostic sensitivity for IgM and IgG were 100%; diagnostic specificity for IgM - 60%, for IgG - 72%; predictive value of a positive result for IgM - 60%, IgG - 68,18%; predictive value of negative results for IgM and IgG - 100%. The best diagnostic characteristics were found in the test system for the detection of total antibodies to SARS-Cov-2, which must be taken into account when deciding whether to purchase test systems for the detection of antibodies to SARS-Cov-2.

Comparative analysis of the impact of blood collection systems on the results of the study of indicators hemostasis system.

Comparative analysis of the impact of blood collection systems on the results of routine coagulation tests. The aim of this study was to conduct comparative analysis of the effects of blood collection systems on the results of routine coagulation tests. The study involved practically healthy women over 18 years of age female (n=30). Inclusion criteria: practically healthy individuals. Exclusion criteria: taking non-steroidal anti-inflammatory drugs, or oral contraceptives. Blood collection was carried out in the following systems: 1 system-Vacuette Premium,2 system- Improvacuter, 3 system- BD Vacutainer® Plus. Before and after centrifugation, visual assessment of tubes was performed.No signs for the presence of clots, hemolysis, or insufficient filling was observed. In each sample we measured prothrombin time (PV, sec), activated partial thromboplastin time (APTT, sec), and fibrinogen (F, g/l) by clotting method on the automatic coagulometer «Sta Compact¼ («Diagnostica Stago¼, France). The results of laboratory analyses were processed using parametric and non - parametric statistics using The Statistica 12.0 software. At the preanalytical laboratory stage, there were no differences when using systems for blood sampling: the clots and hemolysis were not detected in the samples, the level of filling of the sistems was sufficient. Comparative analysis revealed small, though statistically significant, differences for: PT when comparing Improvacuter wiht Vacuette Premium or BD Vacutainer®; APPT when comparing Improvacuter wiht Vacuette Premium. No differences were observed for Fg levels. Our results support the data available in the literature on the effects of blood-taking systems on hemostasis , which should be taken into account when purchasing blood collection systems.