Rajna Minić

Background: The Global Action Plan for Influenza Vaccines, launched by the World Health Organization in 2006, aimed to expand global manufacturing capacity, ensure equitable access to influenza vaccines, and reduce global vaccine shortages. The Institute of Virology, Vaccines and Sera “Torlak” was recognized as a partner and participated in a technology transfer programme to improve national production capabilities. Preclinical studies conducted in 2013 and 2014 provided comprehensive toxicological evidence supporting the safety of the trivalent influenza vaccine manufacturing platform. Nearly a decade later, this validated platform enabled the independent development of a quadrivalent influenza vaccine. Subsequent preclinical studies conducted in accordance with European Medicines Agency guidelines demonstrated preserved immunogenicity despite the inclusion of an additional antigen. Methods: Preclinical evaluation included standard safety and immunogenicity assessments in animal models. Safety assessment included evaluation of systemic parameters (general health status, leukocyte profile, blood biochemistry, and histopathology) and local reactions. Immunogenicity of both trivalent and quadrivalent formulations was assessed using haemagglutination inhibition and microneutralization assays. Results: No significant systemic or local adverse effects were observed. Both trivalent and quadrivalent formulations induced robust immune responses, with immunogenicity comparable to that of corresponding commercial vaccines. Conclusions: These findings confirm the safety profile and demonstrate strong immunogenicity for both the trivalent and quadrivalent formulations, supporting the successful establishment of a national influenza vaccine platform, contributing to increased pandemic preparedness and sustainable influenza vaccine production.

Background: Chronic obstructive pulmonary disease (COPD) is characterised by obstruction of the small airways and includes "flare-ups", which are sudden and significant worsening of symptoms, sometimes caused by infections. Methods: Patients with COPD (n = 38) and acute bronchitis (AB, n=35) were grouped based on age and examined at two time points: during flare-ups/infections and at day 30. We measured various biomarkers, including total plasma TGF-β1 levels, total IgA, total IgM, and Pseudomonas aeruginosa-specific IgA levels. Results: Increased TGF-β1 levels were detected in COPD patients in comparison to acute bronchitis patients, with no significant change observed at day 30. Paired analysis revealed a significant decrease in total plasma IgA levels in COPD patients on day 30. No significant difference in specific P aeruginosa IgA levels was observed between the two patient groups. Interestingly, a correlation between total IgM and IgA levels was absent in COPD patients, unlike in those with acute bronchitis. While a positive correlation existed between age and IgA level in patients with acute bronchitis, this correlation was negative in patients with COPD. A significant correlation was observed between total IgM and P aeruginosa-specific IgA in acute bronchitis patients. On the other hand, COPD patients showed no correlation between total IgA or IgM and P aeruginosa-specific IgA levels at different time points. Conclusions: We report on the deregulated IgA-IgM axis in COPD and call for thorough, larger-scale studies of the humoral immune system in this pathology.

Background/Objectives: The prevalence of obesity worldwide has rapidly increased. Numerous studies showed a beneficial effect of probiotics in obese individuals, and changes in hematological parameters are observed in obesity. Therefore, the aim of this study was to investigate the effect of a novel probiotic approach on the red blood cells (RBCs) and platelets. Methods: Twenty-five obese women participated in a randomized, placebo-controlled study and were divided into the experimental group (one capsule daily containing Lactiplantibacillus plantarum 299v (DSM9843), Saccharomyces cerevisiae var. boulardii, and 40 mg octacosanol; n = 13) and the placebo group (n = 12). Blood samples were collected for light microscopic examination, morphometric analysis, and an automated hematology analyzer. A possible relationship between hematological parameters and body mass index (BMI), a common indicator of obesity, was investigated using Spearman correlation. The plasma concentration of soluble P-selectin and fibrinogen were determined using an ELISA assay. All measurements were performed before (T0) and after 12 weeks of supplementation (T1). Results: The three-month supplementation of probiotics improved hemoglobin levels, chromic status, and red blood cell morphology. The mean platelet volume (MPV), a measure of platelet size, was restored to normal levels, platelet morphology was improved, and the number of activated platelets was significantly reduced (p < 0.05). A strong negative correlation (r = −0.5904, p < 0.05) was found between BMI and platelet distribution width (PDW), a measure of variation in platelet size and shape. Conclusions: The results show that the probiotic approach improves morphology and normalizes the values of disturbed hematological parameters of RBCs and platelets in obese women.

Introduction/Objective. IgA multiple myeloma has a poor prognosis, and altered glycosylation of myeloma IgA may be one of contributing factors. This study examined the expression of terminal galactose and sialic acid (SA) on serum IgA oligosaccharides in patients with IgA myeloma, compared to healthy control sera. Methods. Serum samples from 15 IgA myeloma patients and pooled serum from 100 healthy donors were analyzed. IgA was purified using peptide M affinity chromatography. Terminal galactose and SA expression on isolated IgA was analyzed by RCA I and SNA lectin blotting. Results. IgA heavy chains from both healthy individuals and all myeloma patients expressed galactose. SA was present in healthy control and in 14 out of 15 myeloma patients. Compared to controls, myeloma IgA showed 12-63% a reduction in galactose and a 67-97% reduction in SA expression on heavy chains. Notable galactosylation of IgA light chains was observed in only 3, while weak SA expression was seen in 14 myeloma cases. Healthy IgA was predominantly monomeric and expressed both galactose and SA. Myeloma IgA existed in both and polymeric forms of myeloma expressing detectable galactose level, though with different expression levels among individuals. At the same time SA was undetectable. Conclusion. The results of this study showed altered glycosylation of myeloma IgA. Compared to healthy control, myeloma IgA heavy chains expressed reduced terminal galactose and sialic acid. Notable galacosylation of light chains was observed in three cases. Unlike sialic acid, galactose was detectable on intact monomeric and polymeric multiple myeloma IgA.

Background The progression of monoclonal gammopathies is affected by a range of factors, including the microenvironment surrounding plasma cells. It is recognized that TGF-β1 plays a distinct role in stimulating IgA production. Hence, this study aims to investigate whether individuals with serum IgA monoclonal immunoglobulins (paraproteins) exhibit elevated total TGF-β1 levels compared to those with IgG or IgM paraproteins. Method To achieve this goal, individuals with a positive laboratory findings of monoclonal gammopathy, were segregated according to the paraprotein class, as well as according to the type of the light chain. Total TGF-β1 levels were assessed in blood serum samples containing IgG (n = 50), IgM (n = 31), and IgA (n = 46) paraproteins. Results Elevated level of TGF-β1 was confirmed in sera with IgA paraproteins (median 25.8 ng/ml; interquartile range IQR: 19.0-33.7) compared to those having IgG (median: 18.2 ng/ml; IQR: 14.3–22.1; P < 0.001) or IgM paraproteins (21.5 ng/ml; IQR: 15.0-27.4; P = 0.043). Also, higher TGF-β1 level was detected in sera with IgMλ then those with IgMκ paraproteins (P = 0.043). Conclusions This research affirms the role of TGF-β1 in the pathophysiology of IgA monoclonal gammopathies and potential switch towards IgA isotype, known for less favorable prognosis.

Myasthenia gravis (MG) is a disease with impaired transmission at the neuromuscular junction, characterised by weakness and fatigability of skeletal muscles. In acquired autoimmune MG, antibodies against acetylcholine receptor (AChRAb) or muscle-specific tyrosine kinase (MuSKAb) are present. There is not much data about immunoglobulin G (IgG) galactosylation in MG, and none based on interactions with lectins. This study aims to examine IgG galactosylation in two types of myasthenia, using affinity immunoelectrophoresis with lectin concanavalin A (Con A). Affinity of Con A-IgG interaction, expressed as retardation coefficient (R), indicated the presence of degalactosylated IgG. The average R values were significantly different between three examined groups, being the lowest in controls (healthy subjects), higher in acetylcholine receptor (AChR) MG, and the highest in muscle-specific tyrosine kinase (MuSK) MG (ANOVA, p < .05). This indicated decreased galactosylation of IgG in both types of MG compared to controls, more pronounced in MuSK MG. IgG galactosylation was also investigated in relation to the disease severity score, determined according to the Myasthenia Gravis Foundation of America (MGFA) criteria, at the time of diagnosis, nadir of the disease and last check-out visit. The average R values for mild disease (stages I-IIIa) were significantly lower than for severe disease (stages IIIb-V), both at the time of diagnosis (p < .05), and at the nadir of the disease (p < .05). Thus, IgG galactosylation was associated with the presence of specific autoantibodies in MG, as well as with disease severity for both types of MG, and may be a predictive marker of MG outcome.

Background: Recent literature data highlights metabolic changes in amyotrophic lateral sclerosis (ALS). To explore possible early metabolic changes, we aimed to analyse the fatty acids (FA) composition of erythrocytes in newly diagnosed als patients and to see whether fatty acid levels correlate with the ALSFRS-R score or disease duration. Methods: The severity of motor function involvement was assessed by the ALSFRS-R scale at the initial evaluation. The fatty acid profile of erythrocyte membranes was analysed by gas-liquid chromatography. The study comprised 26 clinically diagnosed als patients, with mean ALSFRS-R 38±8. The control group included 26 healthy volunteers. Results: Significantly higher levels of palmitic acid and total saturated FAs were detected in als patients. In als patients, total monounsaturated FA, palmitoleic, vaccenic, and oleic acid were also significantly increased. The levels of eicosapentaenoic acid, docosapentaenoic acid, total polyunsaturated FA (PUFA) and n-6 PUFA were significantly lower in als patients. Additionally, a-linolenic acid, the precursor of the n-3 PUFA family, was not detected in als patients. We found no significant correlation between the ALSFRS-R score and the abundance of individual FAs analysed. A moderate negative correlation was found between disease duration and DHA level, and a positive correlation was detected with MUFA. Conclusion: Experimental evidence presented may contribute to shaping a beneficial nutritional intervention.