High Concentration of Anti-SARS-CoV-2 Antibodies 2 Years after COVID-19 Vaccination Stems Not Only from Boosters but Also from Widespread, Often Unrecognized, Contact with the Virus.

This study follows 99 subjects vaccinated with Pfizer/BioNTech COVID-19 vaccines over two years, with particular focus on the last year of observation (between days 360 and 720). The response to the vaccination was assessed with Diasorin's SARS-CoV-2 TrimericSpike IgG. Screening for SARS-CoV-2 infection was performed with Abbott's SARS-CoV-2 Nucleocapsid IgG immunoassay. Data from questionnaires were also analyzed. Two years after the first vaccine dose administration, 100% of the subjects were positive for anti-spike SARS-CoV-2 IgG and the median antibody level was still high (3600 BAU/mL), dropping insignificantly over the last year. Simultaneously, a substantial increase in seropositivity in anti-nucleocapsid SARS-CoV-2 IgG was noted, reaching 33%. There was no statistically significant agreement between anti-N seropositivity and reported COVID-19. Higher anti-spike concentrations and lower COVID-19 incidence was seen in the older vaccinees. It was noted that only subjects boosted between days 360 and 720 showed an increase in anti-spike IgG concentrations. The higher antibody concentrations (median 7440 BAU/mL) on day 360 were noted in participants not infected over the following year. Vaccination, including booster administrations, and natural, even unrecognized, contact with SARS-CoV-2 entwined two years after the primary vaccination, leading to high anti-spike antibody concentrations.

A comparison of 7 commercial anti-SARS-CoV-2 antibody immunoassays.

Introduction: Serological testing in SARS-CoV-2 infection is gaining both patients' and clinicians' attention. Antibody assessment has potential multidirectional utility, hampered by the scarcity of clinical validation studies of the tests available on the market. Therefore, this study aimed to provide some evidence on the clinical utility of anti-SARS-CoV-2 commercial assays, based on the comparison of the results obtained with different methods. Material and methods: The study included 52 samples from patients and healthy volunteers. The control samples (n = 20) were obtained during the SARS-CoV-2 pandemic. The case cohort consisted of 32 consecutive patients referred to the Diagnostyka medical laboratory for anti-SARS-CoV-2 antibody testing. For the purpose of this study, the MAGLUMI chemiluminescent immunoassay (CLIA) was chosen as a comparative method. All samples were tested with this method, as well as with the Euroimmun enzyme-linked immunosorbent assay (ELISA) and five different lateral flow immunoassays (LFIAs). Results: The results obtained in this study provide evidence for high overall concordance between the comparative CLIA method and both ELISA and different LFIAs. The agreement between CLIA and LFIAs was 92.3-98.0% for IgG and 90.0-96.1% for IgM, depending on the kit. The concordance between CLIA and ELISA was 92.3% for IgG and 75.0% for IgA (compared to the MAGLUMI CLIA IgM). Conclusions: The results obtained in this study provide evidence for high overall concordance between the comparative CLIA method and different LFIAs. This could justify the use of LFIAs in some settings, where automated assays are not available, provided that some limitations are considered.

The Influence of Booster Shot and SARS-CoV-2 Infection on the Anti-Spike Antibody Concentration One Year after the First COVID-19 Vaccine Dose Administration.

This study pictures the humoral response of 100 vaccinees to Pfizer/BioNTech COVID-19 vaccine over a year, with particular focus on the influence of a booster shot administered around 10 months after the primary immunization. The response to the vaccination was assessed with Diasorin's SARS-CoV-2 TrimericSpike IgG. Abbott's SARS-CoV-2 Nucleocapsid IgG immunoassay was used to identify SARS-CoV-2 contact, even asymptomatic. In contrast to the gradual decline of the anti-spike IgG between 30 and 240 days after the first dose, an increase was noted between days 240 and 360 in the whole cohort. However, a statistically significant rise was seen only in boosted individuals, and this effect of the booster decreased over time. An increase was also observed in non-boosted but recently infected participants and a decrease was reported in non-boosted, non-infected subjects. These changes were not statistically significant. On day 360, a percentage of new SARS-CoV-2 infections was statistically lower in the boosted vs. non-boosted subgroups. The booster immunization is the most efficient way of stimulating production of anti-spike, potentially neutralizing antibodies. The response is additionally enhanced by the natural contact with the virus. Individuals with a low level of anti-spike antibodies may benefit the most from the booster dose administration.

Head-to-Head Comparison of 5 Anti-SARS-CoV-2 Assays Performance in One Hundred COVID-19 Vaccinees, over an 8-Month Course.

The immunoassays used to measure anti-spike SARS-CoV-2 antibodies are widely available on the market. However, their performance in COVID-19 vaccinees is not yet adequately assessed. Our study provides a head-to-head comparison of five methods: Abbott's S1-RBD IgG, Roche's S1-RBD total antibody, Euroimmun's S1 IgG, and DiaSorin's TrimericS IgG and S1/S2 IgG assays. Testing was performed in one hundred vaccinated subjects, at eight timepoints over eight months after vaccination. The results differed substantially between methods; however, they correlated strongly and demonstrated the individuals' responses to both doses of vaccination and the waning of humoral immunity after eight months. Importantly, we encountered a high percentage of results above the assay-specific upper quantitation limit (UQL) for undiluted samples. This was the most pronounced for the Roche's and Euroimmun's assays. The Abbott's assay showed the lowest percentage of results above the UQL. We also attempted to find a common way to establish antibody concentrations that might be classified as high. However, this resulted in between 10% and 100% of such results for different methods on day 240'. This highlights the need for an assay-specific approach for adjusting the cut-offs that may indicate COVID-19 immunity.

Anti-Spike SARS-CoV-2 IgG Assessment with a Commercial Assay during a 4-Month Course after COVID-19 Vaccination.

We intended to assess the humoral response induced by the Pfizer/BioNTech Comirnaty COVID-19 vaccine with commercially available immunoassays: anti-spike (S) IgG and IgM, and anti-nucleocapsid (N) IgG antibodies, over a 4-month course. One hundred subjects, including 15 COVID-19 convalescents, comprised the study cohort. The SARS-CoV-2 antibodies concentrations were measured on day 0' and 10', 20', 30', 60', 90', and 120' after the first dose administration. Over the course of the study, 100% of the participants developed and sustained anti-SARS-CoV-2 S IgG antibodies. The highest concentration, exceeding the quantification range of the test (2080 BAU/mL), was reached by 67% of the subjects on day 30'. The concentration of the antibodies remained stable between days 30' and 90' but was followed by a significant decrease between days 90' and 120'. The stronger and more persistent humoral response was noted for women. The COVID-19 convalescents developed higher antibody levels, particularly 10 days after the first Comirnaty dose. Twenty-three out of the eighty-five naïve vaccinees failed to develop a detectable IgM response. LIAISON® SARS-CoV-2 TrimericS IgG (DiaSorin S.p.A, Saluggia, Italy) may be useful in the assessment of the humoral response to the Comirnaty vaccine. In contrast, Abbott's anti-S SARS-CoV-2 IgM has a limited utility in this context.

The real life performance of 7 automated anti-SARS-CoV-2 IgG and IgM/IgA immunoassays.

OBJECTIVES: This study was aimed at providing some insights into the real-life performance of the commercial, clinically validated anti-SARS-CoV-2 antibody assays. METHODS: The residual, anonymized samples from 97 patients referred for anti-SARS-CoV-2 antibodies testing were included in the study. The initial assessment was performed with the Euroimmun ELISAs, followed by the assays provided by: NovaTec, Snibe, Vircell, Roche, Abbott and DiaSorin. The analyses of the results were performed separately for the antibodies of the early (IgM/IgA) and late (IgG) immune response. RESULTS: We observed a high variability of the results obtained with the investigated immunoassays. The fully concordant results were reported for only 57 out of 97 samples tested for IgG antibodies and for 34 out of 97 samples for IgM/IgA. The highest percentage of positive results was noted for the Euroimmun and Vircell ELISAs and the lowest for Novatec ELISAs.We proposed to distinguish true and false positive results based on the sum of positive results obtained with different methods. We arbitrarily considered reference positive samples reactive in at least half of the assays. The assay that proved to correlate the best with those reference results was the Roche electrochemiluminescence immunoassay. CONCLUSIONS: The differences observed between immunoassays targeting the early phase antibodies were much more pronounced than between IgG assays, suggesting their lower value for clinical use. Our study also showed a high percentage of plausibly false (positive or negative) results obtained with ELISAs, which suggests their inferiority to the automated immunoassays.

"PoZdro!" as an example of a successful multicenter programme for obesity management and healthy lifestyle promotion in children and adolescents - programme protocol and preliminary results from the first intervention site.

INTRODUCTION: Overweight and obesity rates in children and adolescents increase worldwide for over 30 years, what leads to an increased risk of de-veloping metabolic diseases. AIM OF THE STUDY: Protocol description and preliminary results of the largest to-date obesity management programme for children in Poland - "PoZdro!" MATERIAL AND METHODS: The Programme is based on three main steps: screening, parental engagement and long-term behavioral intervention (medical, dietetic, psychological, physical activity intervention panels) and education activities in secondary schools. Over 30.000 children were screened in four big Polish cities and over 2.000 engaged in the programme. RESULTS: Preliminary results from the first city show that, since 2014, 3998 of the 6346 (63%) eligible students from 24 schools (first grade of the secondary school) were screened. 16% of the children were overweight (body mass index - BMI ≥ 85th < 95th centile) and 4.7% were obese (BMI ≥95th centile). 603 children fulfilling the qualification (QUA) criteria (BMI > 90th centile) were offered the Individual Integrated Care (IIC). 470 (77.94% of QUA) began and 253 (41.96% of QUA, 53.82% of IIC) finished the full interventional pro-gramme with the mean BMI centile decrease of 3.04 in two following years. CONCLUSIONS: "PoZdro!" is a unique obesity prevention and management programme in Poland operating simultaneously in several Polish big cities. The programme incorporates parental engagement and long-term behavioral intervention. Preliminary results show that it may result in meaningful decrease in BMI in two following years. Further data analyses are necessary to show the influence of the programme on metabolic risk in studied group.

The association of thyroid-stimulating hormone (TSH) and free thyroxine (fT4) concentration levels with carbohydrate and lipid metabolism in obese and overweight teenagers.

INTRODUCTION: Obesity has increased rapidly among children and adolescents during the last 30 years. Paediatric patients with a BMI above the 85th centile are more often diagnosed with increased TSH levels than are children with proper body weight. MATERIAL AND METHODS: The data of 961 overweight and obese children, aged 13 years, recruited in four cities in Poland as part of PoZdro!, a two-year prophylactic program, were analysed to observe the relationship between serum TSH and fT4 concentration and carbohydrate and lipid metabolism parameters, as well as anthropometric parameters. RESULTS: TSH concentration in the study group was positively correlated, whereas fT4 concentration was negatively correlated with WHR and WHtR values, fasting serum glucose concentrations and one-hour glucose concentration, fasting serum insulin concentrations, one-hour and two-hour insulin concentration, ALT serum activity, as well as total cholesterol, LDL cholesterol, and triglyceride serum concentrations. An increased risk of metabolic syndrome was diagnosed previously in patients with TSH concentrations > 2.5 mUI/L. CONCLUSIONS: TSH concentration in the upper half of the current reference range (> 2.50 mIU/L) is associated with an increased risk of lipid and carbohydrate metabolism disorders and therefore increased chances of developing metabolic syndrome. It seems advisable to regularly monitor thyroid function in overweight and obese paediatric patients.

Intra-operative biopsy in chronic sinusitis detects pathogenic Escherichia coli that carry fimG/H, fyuA and agn43 genes coding biofilm formation.

The aim of this study was to investigate whether or not surgical biopsy of sinus tissue in chronic sinusitis, not responsive to treatment, would detect E. coli. We intended to evaluate E. coli virulence genes, therefore dispute the causal role of such an unusual microorganism in chronic sinusitis, as well as consider effective pathogen-targeted therapy. Patients with E. coli isolated by intra-operative puncture biopsy were included in the study. Genetic analysis of E. coli isolates, including phylogenetic grouping and virulence factor characteristics, were done by multiplex PCR. We identified 26 patients with chronic sinusitis, in which 26 E. coli isolates were cultured. The E. coli isolates belonged mainly to pathogenic phylogenetic group B2, and carried multiple virulence genes. Three genes in particular were present in all (100%) of examined isolates, they were (1) marker agn43 gene for forming biofilm, (2) type 1 fimbriae (fimG/H gene) and (3) yersiniabactin receptor (fyuA). Furthermore, a pseudo-phylogenetic tree of virulence genes distribution revealed possible cooperation between agn43, fimG/H, and fyuA in the coding of biofilm formation. Intra-operative-biopsy and culture-based therapy, targeting the isolated E. coli, coincided with long-term resolution of symptoms. This is the first report demonstrating an association between a highly pathogenic E. coli, chronic sinus infection, and resolution of symptoms upon E. coli targeted therapy, a significant finding due to the fact that E. coli has not been considered to be a commensal organism of the oropharynx or sinuses. We postulate that the simultaneous presence of three genes, each coding biofilm formation, may in part account for the chronicity of E. coli sinusitis.

Acid ribonuclease and alkaline ribonuclease isoenzymes in plasma of patients with decreased glomerular filtration rate.

Removal of low molecular weight proteins from plasma by kidneys depends on glomerular filtration rate (GFR), protein-glomerular membrane electric charge, steric interactions and a number of functionally active nephrons present in the kidneys. There is a well documented relationship between the concentration of low molecular weight proteins in plasma and GFR value in patients with impaired renal function. Accumulation of low molecular weight proteins in plasma along with a decrease in GFR value may in the long run enhance formation of protein tissue deposits known as various forms of amyloidosis. In this paper we present studies on plasma concentrations of acid leukocyte-type ribonuclease (RNase) and alkaline pancreatic-type RNase and GFR value in 54 patients with renal failure. RNase isoenzymes' activities were assayed by measuring their enzyme activities manifested as ability to decompose yeast RNA and assay of digestion products' concentration by spectrophotometry. The studies show that decreasing filtration rate produces an increase in serum activities of both acid and alkaline RNases, which is proportional to the logarithm of GFR value. However, the increase rate vs. GFR value is by four times higher for acid RNase than for alkaline RNase. Acid RNase in human plasma is mostly of leukocytic origin and differs from pancreatic-type alkaline RNase, which is of pancreatic origin. The obtained results may suggest that leukocyte originating proteins essentially contribute to low molecular weight protein accumulation in plasma of patients with chronic renal insufficiency.

Dialysis adequacy, residual renal function and serum concentrations of selected low molecular weight proteins in patients undergoing continuous ambulatory peritoneal dialysis.

BACKGROUND: Low molecular weight proteins (LMWP) are considered uremic toxins. There is controversy whether in peritoneal dialysis (PD) the elimination of these toxins is influenced mainly by dialysis or by residual renal function (RRF). MATERIAL/METHODS: The aim of our study was to evaluate the relationship between serum levels of selected LMWPs, dialysis adequacy, and RRF in PD patients. 27 stable subjects were studied, mean age 50+/-11, dialyzed for a median period of 10 months. Serum activity of acid RNA-se and alkaline RNA-se was measured by spectrophotometry, and serum alpha1-microglobulin ((alpha) 1M) concentration by ELISA. Kt/V and weekly creatinine clearance (wClCr) were assessed as adequacy indices (both as the sum of renal and dialysis components) and RRF as the mean of residual urea and creatinine clearances. RESULTS: Significant inverse correlations were found between RRF and (alpha) 1M level, as well as alkaline RNA-se activity (p<0.0001). A similar relationship was found for residual Kt/V (p<0.0001 for (alpha) 1M and alkaline RNA-se). There was no significant correlation between acid RNA-se activity and any tested parameter of adequacy. When the cutoff points of wClCr = 60 L/week/m2, total Kt/V = 2.0, or RRF=2.0 ml/min were used, we found (alpha)1M level and alkaline RNA-se activity to be significantly lower in patients with higher values of the CONCLUSIONS: RRF plays an important role in elimination of LMWP in PD. The activity of alkaline RNA-se and acid RNA-se behaves differently in these patients.