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The paper describes the synthesis of an aminopropyl glycoside of hexasaccharide structurally related to the branched fragment of Candida utilis glucomannan, consisting of tetra-α-(1→2)-d-mannoside, the non-reducing end of which is glycosylated with α-glucopyranose and α-mannopyranose residues attached through the (1→2) and (1→3) linkages, respectively. The target structure was assembled by block synthesis with controlled α-stereoselectivity of formation of each glycosidic bond. The resulting hexasaccharide was further converted to a biotinylated conjugate, which, together with previously synthesized similar oligosaccharides, will be used to study the antigenic properties of mannans of Candida fungi. [ABSTRACT FROM AUTHOR]

Background: The SARS-CoV-2 pandemic has resulted in an unprecedented level of worldwide testing for epidemiologic and diagnostic purposes, and due to the extreme need for tests, the gold-standard Reverse Transcription Polymerase Chain Reaction (RT-PCR) testing capacity has been unable to meet the overall worldwide testing demand. Consequently, although the current literature has shown the sensitivity of rapid antigen tests (RATs) to be inferior to RT-PCR, RATs have been implemented on a large scale without solid data on performance. Objective: This study will compare analytical and clinical sensitivities and specificities of 50 lateral flow-- or laboratory-based RATs and 3 strand invasion--based amplification (SIBA)-RT-PCR tests from 30 manufacturers to RT-PCR testing of samples obtained from the deep oropharynx. In addition, the study will compare sensitivities and specificities of the included RATs as well as RT-PCR on clinical samples obtained from the deep oropharynx, the anterior nasal cavity, saliva, the deep nasopharynx, and expired air to RT-PCR on deep oropharyngeal samples. Methods: In the prospective part of the study, 200 individuals found SARS-CoV-2 positive and 200 individuals found SARS-CoV-2 negative by routine RT-PCR testing will be retested with each RAT, applying RT-PCR as the reference method. In the retrospective part of the study, 304 deep oropharyngeal cavity swabs divided into 4 groups based on RT-PCR quantification cycle (Cq) levels will be tested with each RAT. Results: The results will be reported in several papers with different aims. The first paper will report retrospective (analytical sensitivity, overall and stratified into different Cq range groups) and prospective (clinical sensitivity) data for RATs, with RT-PCR as the reference method. The second paper will report results for RAT based on anatomical sampling location. The third paper will compare different anatomical sampling locations by RT-PCR testing. The fourth paper will focus on RATs that rely on central laboratory testing. Tests from 4 different manufacturers will be compared for analytical performance data on retrospective deep oropharyngeal swab samples. The fifth paper will report the results of 4 RATs applied both as professional use and as self-tests. The last paper will report the results from 2 breath tests in the study. A comparison of sensitivity and specificity between RATs will be conducted using the McNemar test for paired samples and the chi-squared test for unpaired samples. Comparison of the positive predictive value (PPV) and negative predictive value (NPV) between RATs will be performed by the bootstrap test, and 95% CIs for sensitivity, specificity, PPV, and NPV will be calculated as bootstrap CIs. Conclusions: The study will compare the sensitivities of a large number of RATs for SARS-CoV-2 to with those of RT-PCR and will address whether lateral flow--based RATs differ significantly from laboratory-based RATs. The anatomical test locations for both RATs and RT-PCR will also be compared. [ABSTRACT FROM AUTHOR]

This paper analyzes the literature data on the role of cytokines in the pathogenesis of malignant neoplasms. Cytokines are biologically active, hormone-like proteins that regulate a wide range of processes occurring in the body. Cytokines determine the type and duration of the immune response, stimulation or suppression of cell growth, and their differentiation and functional activity. The complex of cytokines produced in the tumor microenvironment play an important role in the pathogenesis of malignant neoplasms. The spectra of biological activities of cytokines in most cases overlap. The same process in a cell can be stimulated by more than one cytokine, creating a favorable environment for the initiation and progression of cancer. The immune system can recognize transformed cells. Various cytokines correspond to specific pathways activated by receptors on the cell surface, which, in turn, induce intracellular signaling cascades that affect targeted cellular functions. Cytokine genes are mutually associated with oncogenes. Cytokines that are released in response to infection or inflammation or in the course of an immune response to an antigen can suppress tumor development. In turn, cytokines that attenuate apoptosis and promote invasion and metastasis promote tumor growth. Cytokines are involved in the initiation, development, and metastasis of malignant neoplasms through various mechanisms. [ABSTRACT FROM AUTHOR]

Simple Summary: The detection of animal viruses remains a formidable scientific challenge, while concurrently presenting a profoundly consequential practical concern of considerable magnitude, necessitating the development of rapid, sensitive, specific, on-site, cost-effective, and user-friendly diagnostic assays. In response to this demand, electrochemical biosensors have garnered significant attention from researchers. In our review, we comprehensively assess the recent research progress pertaining to electrochemical biosensors for animal viral detection, with a particular focus on the application of screen-printed electrodes. Animal viruses are a significant threat to animal health and are easily spread across the globe with the rise of globalization. The limitations in diagnosing and treating animal virus infections have made the transmission of diseases and animal deaths unpredictable. Therefore, early diagnosis of animal virus infections is crucial to prevent the spread of diseases and reduce economic losses. To address the need for rapid diagnosis, electrochemical sensors have emerged as promising tools. Electrochemical methods present numerous benefits, including heightened sensitivity and selectivity, affordability, ease of use, portability, and rapid analysis, making them suitable for real-time virus detection. This paper focuses on the construction of electrochemical biosensors, as well as promising biosensor models, and expounds its advantages in virus detection, which is a promising research direction. [ABSTRACT FROM AUTHOR]

Tick and tick-borne disease control have been a serious research focus for many decades. In a global climate of increasing acaricide resistance, host immunity against tick infestation has become a much-needed complementary strategy to common chemical control. From the earliest acquired resistance studies in small animal models to proof of concept in large production animals, it was the isolation, characterization, and final recombinant protein production of the midgut antigen Bm86 from the Australian cattle tick strain of Rhipicephalus (Boophilus) microplus (later reinstated as R. (B.) australis) that established tick subunit vaccines as a viable alternative in tick and tick-borne disease control. In the past 37 years, this antigen has spawned numerous tick subunit vaccines (either Bm86-based or novel), and though we are still describing its molecular structure and function, this antigen remains the gold standard for all tick vaccines. In this paper, advances in tick vaccine development over the past three decades are discussed alongside the development of biotechnology, where existing gaps and future directives in the field are highlighted. [ABSTRACT FROM AUTHOR]

The simulation of immune response is a challenging task because quantitative data are scarce. Quantitative theoretical models either focus on specific cell–cell interactions or have to make assumptions about parameters. The broad variation of, e.g., the dimensions and abundance between lymph nodes as well as between individual patients hampers conclusive quantitative modeling. No theoretical model has been established representing a consensus on the set of major cellular processes involved in the immune response. In this paper, we apply the Petri net formalism to construct a semi-quantitative mathematical model of the lymph nodes. The model covers the major cellular processes of immune response and fulfills the formal requirements of Petri net models. The intention is to develop a model taking into account the viewpoints of experienced pathologists and computer scientists in the field of systems biology. In order to verify formal requirements, we discuss invariant properties and apply the asynchronous firing rule of a place/transition net. Twenty-five transition invariants cover the model, and each is assigned to a functional mode of the immune response. In simulations, the Petri net model describes the dynamic modes of the immune response, its adaption to antigens, and its loss of memory. [ABSTRACT FROM AUTHOR]

The paper aimed to present the Physiological Tolerance Test of Combination Treatment of Antigen-G and Curcumin Extract on VEGF Levels, Mortality Rate of BALB/c. This research consists of several stages. The TMd-G antigen (ITMd) was isolated from the thoracic segments of Musca domestica larvae 4th instar stage and the thoracic segments of the adult cycle stage, 5 days old. The larvae were obtained from the rearing process using defined media. Curcumine extract (EK) was obtained from Curcuma xanthorrhiza rhizomes through the process of broyage, mixing, precipitation, lyophilization and collection of dry EK. The VEGF serum molecules were significant higher (P<0.05) in Ek20Ag3 to Ek20Ag9 then in other combination treatment. The zero-mortality rate obtained in using AgLMd. [ABSTRACT FROM AUTHOR]

In this paper, we use terahertz combined with metamaterial technology as a powerful tool to identify analytes at different concentrations. Combined with the microfluidic chip, the experimental measurement can be performed with a small amount of analyte. In detecting the troponin antigen, surface modification is carried out by biochemical binding. Through the observation of fluorescent antibodies, the average number of fluorescent dots per unit of cruciform metamaterial is 25.60, and then, by adjusting the binding temperature and soaking time, the average number of fluorescent dots per unit of cruciform metamaterial can be increased to 181.02. Through the observation of fluorescent antibodies, it is confirmed that the antibodies can be successfully stabilized on the metamaterial and then bound to the target antigen. The minimum detectable concentration is between 0.05~0.1 μg/100 μL, and the concentration and ΔY show a positive correlation of R2 = 0.9909. [ABSTRACT FROM AUTHOR]

The paper reports the assessment of the role of surface antigens in Yersinia pestis adhesion to murine macrophages J774. The ability of Ail and Psa antigens to adhere to eukaryotic cells has been confirmed using optical trapping and/or passive adhesion methods. The YapF autotransporter was shown for the first time to be an adhesin of Y. pestis. It has been suggested that these antigens do not have complementary receptors on the macrophage surface and their adhesive properties are nonspecific. The results of studying passive adhesion of polystyrene microspheres sensitized with the F1 capsular antigen to J774 macrophages suggest that its inhibiting effect on the adhesion to macrophages is determined not only by spatial shielding of underlying adhesins by the capsule but also by physical and chemical properties of the antigen itself. [ABSTRACT FROM AUTHOR]

Detection and imaging of viruses in a complex solution is particularly significant for virology and requires a comprehensive understanding of biosensors. While lab-on-a-chip systems are used in virus detection as biosensors, analysis and optimization of these systems are especially challenging due to the size of the system to be used in the certain application. The system of interest for virus detection is required to be cost efficient and is also needed to be able to easily operable with a simple setup. Moreover, the detailed analysis of these microfluidic systems should be made with precision in order to predict the capabilities and the efficiency of the system accurately. This paper reports on the use of a common commercial computational fluid dynamics (cfd) software for the analysis of a microfluidic lab-on-a-chip virus detection cartridge. This study evaluates the problems commonly encountered during microfluidic applications of cfd softwares particularly in the area of reaction modeling of the antigen-antibody interaction. cfd analysis is later validated and combined with experiments to optimize the amount of dilute solution used in the tests. Thereafter, the geometry of the microchannel is also optimized and optimal test conditions are set for a cost efficient and effective virus detection kit using light microscopy. [ABSTRACT FROM AUTHOR]

At present, severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) is raging worldwide, and the coronavirus disease 2019 outbreak caused by SARS‐CoV‐2 seriously threatens the life and health of all humankind. There is no specific medicine for novel coronavirus yet. So, laboratory diagnoses of novel coronavirus as soon as possible and isolation of the source of infection play a vital role in preventing and controlling the epidemic. Therefore, selecting appropriate detection techniques and methods is particularly important to improve the efficiency of disease diagnosis and treatment and to curb the outbreak of infectious diseases. In this paper, virus nucleic acid, protein, and serum immunology were reviewed to provide a reference for further developing virus detection technology to provide better prevention and treatment strategies and research ideas for clinicians and researchers. Highlights: Laboratory diagnoses of novel coronavirus play a vital role in the whole epidemic situation.Nucleic acid, protein and serum immunoassay of viruses are the main methods.RT‐PCR has become the gold standard for SARS‐CoV‐2 detection because of its high sensitivity and strong specificity. [ABSTRACT FROM AUTHOR]

Clenbuterol is a β-adrenergic receptor agonist that can be used as a bronchodilator for the treatment of respiratory diseases or as an additive feed in livestock to improve conversion rate of lean meat. However, the residue of clenbuterol in food can be a threat to human health. Therefore, it is important to monitor clenbuterol in foods. In this paper, a fluorescence inner filtration immunoassay (FIFI) method for the detection of clenbuterol was developed based on the principle of immunoreactive competitive method and the theory of fluorescence quenching, which was constructed from a fluorescence-quenching detection system and a separation system of magnetic immunization. In the magnetic immunization separation system, the detection antigen competes with the biotin-labeled antigen for binding to colloidal gold-labeled clenbuterol antibody and the immunocomplex is enriched by streptavidin- and biotin-specific reactions on the surface of magnetic beads. The remaining complex as a fluorescence quencher in the detection system after centrifugation, and rhodamine 6G acts as a fluorescence agent. The quantitative detection of clenbuterol was accomplished by achieving fluorescence quenching under excitation light irradiation. The standard solutions of clenbuterol in the range of 0.03–5.0 ng/mL exhibited good correlation (r = 0.9996) with the fluorescence intensity, with limit of detection 0.01 ng/mL and recoveries ranging from 98.1 to 101.2%. Moreover, there was no significant difference between the results obtained after testing valid samples by FIFI and ELISA. Therefore, our developed method is sensitive and efficient, simple to operate, and has great potential for on-site detection of clenbuterol. [ABSTRACT FROM AUTHOR]

A rapid change has been undergone in the current pandemic and many countries are being exposed to the third wave of COVID-19. The tireless work for the discovery of vaccine had begun by the time the disease occupied a major part of the globe. This is mainly due to the efficacy of vaccines in preventing diseases and it is one of the cost effective strategies adopted for the prevention of many diseases. Currently a lot of countries have come forth with suitable vaccines to tackle the SARS CoV-2 to some extent. This paper incorporates details about vaccination and the common vaccines in use against COVID-19. Based on the evidences available, keen observations and studies carried out on the previously emerged SARS and MERS, the vaccine against SARS CoV-2 was developed, however the primary focus depend on the spike protein which was considered as a target for the development of suitable immunotherapies and thereby played a potential role in the vaccine development process. Vaccination is the most significant strategy to stop the pandemic and the efficacy of SARS-CoV-2 vaccines provides a genuine gauge of hope for future. [ABSTRACT FROM AUTHOR]

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In preclinical studies, which are conducted to study the therapeutic effectiveness and pharmacological safety of biologically active compounds for the correction of autoimmune thyroiditis, various experimental models of this pathology are used in the experiment. In this work, we analyzed various models of thyroiditis that have been used for the past fifty years. Such an analysis made it possible to choose the most optimal model for the study of autoimmune pathology of the thyroid gland as well as for the correction of this condition. The analysis of known and the search for new pathogenetically justified models of autoimmune diseases of endocrine organs is a very urgent task. The aim of the work was to study the dynamics of changes in the histomorphological structure of the thyroid gland when modeling autoimmune thyroiditis in rats using an allogeneic antigen isolated from the human thyroid gland. The postoperative thyroid gland of a person was used as an antigen. Morphological changes in the thyroid gland were studied one, three and six months after the end of the simulation. It was found that the use of this type of immunization led to changes in the parenchyma of the gland, characteristic of autoimmune thyroiditis. Already one month after modeling, Gürtle cells, fibrosis, areas of lymphoid infiltration of the parenchyma were registered. These pathological changes persisted and worsened three and six months after the end of the simulation. The investigated type of model of experimental autoimmune thyroiditis is easily reproduced. Pathological changes in the gland deepen over time and are comparable to those that occur in people with Hashimoto's thyroiditis. [ABSTRACT FROM AUTHOR]

It is presented the antigenic spectrum and alelofond AEB-locus of reproductive bulls from 5 lines of the Moldavian type of Black-motley cattle. It was found a high frequency of antigenes A2, B2, G2, G3, I2, O2, Y2, D', E'2, G', O', Q', G", C1, C2, E, X2, F, H'. The highest genetical similitude was found in line Rokmen and Astronavt (r=0,8650). The alelofond of the studied lines in AEB-locus includes 95 aleles. The individual homozygote (Cα) of lines of the Moldavian type of Black-motley cattle constitutes 6,8%.

It was studied and compared the antigens’’ frequency of blood groups in the reproductive horned Black and White cattle (n=542) and other five types of horned cattle: Steppe Red (n=54), Red Estonian (n=330), Simmental (n=34). Jersey (n=56), Ukrainian Grey (n=97), who were (directly or indirectly) involved in creation of horned Moldavian Black and White cattle. In tests 48-62 serums from 9-12 loci of sanguinary groups were used. It was calculated the genetic distance between the races and made up a dendrogram. The smallest genetic distance (0.1513) was obtained between the races Steppe Red and Red Estonian. The genetic distances between the improved race Black and White and races Steppe Red and Simmental was 0.1559 – 0.1708.

The range of paraclinical investigations applied in ichthyopathology aims at assessing those parameters that can define the pathological modifications and the physiological condition of the fish material, as well as the defense reaction of the unhealthy body. Modification in value of these indicators points out some metabolic perturbations in fish body. Fish have an immunitary system whose complexity and efficiency are directly proportional to their evolution level. That is why, in comparison to the superior vertebrates, the immune reactions of fish body to an antigenic attack are lower, the immune response is weaker and slower, and the quantity of antibodies to form is low. Under the influence of a specific antigen, the immunoformating cells synthetize the corresponding antibodies, determining occurrence of a specific antigen-antibody reaction, resulting in occurrence of the Ag-Ac immune complexes having a role in annihilating and destroying the respective antigens. Formation of immune complexes (CI) is a normal physiological process within the humoral immunity of bodies, representing one of the methods to remove from the body the substances identified as non-self.

Introduction: Equine asthma (EA) is a common lower airway disease in horses, but whether its pathogenesis is allergic is ambiguous. Extrinsic stimuli like hay dust induce acute exacerbation of clinical signs and sustained local neutrophilic inflammation in susceptible horses. Aspergillus fumigatus is an EA stimulus, but it is unclear if it merely acts as an IgE-provoking allergen. We aimed to comprehensively analyze immunoglobulin (Ig) isotypes in EA, elucidating their binding to different A. fumigatus antigens, and their quantities systemically in serum and locally in bronchoalveolar lavage fluid (BALF). Methods: Serum and BALF from healthy horses (HE, n = 18) and horses with mildmoderate asthma (MEA, n = 20) or severe asthma (SEA, n = 24) were compared. Ig isotype (IgG1, IgG3/5, IgG4/7, IgG6, IgA, and IgE) binding to nine antigens (A. fumigatus lysate, and recombinant Asp f 1, Asp f 7, Asp f 8, dipeptidylpeptidase 5, class II aldolase/adducin domain protein, glucoamylase, betahexosaminidase, and peptide hydrolase) was compared by enzyme-linked immunosorbent assays. Total Ig isotype contents were determined by beadbased assays. Results: MEA and SEA differed from HE but hardly from each other. Compared to HE, asthmatic horses showed increased anti-A. fumigatus binding of IgG (BALF and serum) and IgA (BALF). Serum and BALF IgE binding and total IgE contents were similar between HE and EA. Single antigens, as well as A. fumigatus lysate, yielded similar Ig binding patterns. Serum and BALF IgG1 binding to all antigens was increased in SEA and to several antigens in MEA. Serum IgG4/7 binding to two antigens was increased in SEA. BALF IgA binding to all antigens was increased in SEA and MEA. Total BALF IgG1 and IgG4/7 contents were increased in SEA, and serum IgG4/7 content was increased in MEA compared to HE. Yet, total isotype contents differentiated EA and HE less clearly than antigen-binding Ig. Discussion: A. fumigatus immunogenicity was confirmed without identification of single dominant antigens here. A. fumigatus provoked elevated BALF IgG1 and IgA binding, and these isotypes appear relevant for neutrophilic EA, which does not support allergy. BALF Ig isotype differentiation beyond IgE is crucial for a comprehensive analysis of immune responses to fungi in EA pathogenesis. [ABSTRACT FROM AUTHOR]

The diagnosis of COVID-19 is considered a significant step in the management of the disease that is causing a major worldwide public health challenge from the time of its emergence in December 2019. Since it has been established that SARS-CoV-2 spreads rapidly, timely detection of the positive cases and isolation of such individuals and their contacts helps in containing viral transmission. In this paper, we review the in vitro technology platforms for testing and diagnosing COVID-19 patients: molecular tests, rapid antigen tests, and serology tests. As part of our review of each category of tests, we discuss the commercialized testing platforms, their analyzing systems, specimen collection protocols, and testing methodologies. Moreover, the efficacy and limitations of each technique are also discussed. The key structural components of the virus are presented to provide an understanding of the scientific principles behind the testing tools. [ABSTRACT FROM AUTHOR]

CD39 is the rate-limiting enzyme for the molecular signal cascade leading to the generation of ADP and adenosine monophosphate (AMP). In conjunction with CD73, CD39 converts adenosine triphosphate (ATP) to ADP and AMP, which leads to the accumulation of immunosuppressive adenosine in the tumor microenvironment. This review focuses on the role of CD39 and CD73 in immune response and malignant progression, including the expression of CD39 within the tumor microenvironment and its relationship to immune effector cells, and its role in antigen presentation. The role of CD39- and CD73-targeting therapeutics and cancer-directed clinical trials investigating CD39 modulation are also explored. Executive summary Enzyme structure CD39 is an integral membrane protein that dephosphorylates adenosine triphosphate (ATP) to adenosine monophosphate (AMP) and CD73 further dephosphorylates AMP to adenosine (ADO). These enzymes are expressed on different cell types within the tumor microenvironment. Tumor microenvironment Tumor activity and host immune response hinge on the delicate balance between ATP and ADO accumulation within the tumor microenvironment and include the activation of receptors such as A2A and P2X7. CD39 as a biomarker CD39 expression has been identified as a clinically significant positive predictor of ovarian cancer response to immunotherapy. CD39 & CD73 inhibitor trials Anti-CD39 and anti-CD73 monoclonal antibodies are currently being investigated in clinical trials as monotherapies and in combination, with many underway. Oleclumab, an anti-CD73 monoclonal antibody, has recently been shown to be effective with a tolerable safety profile in treating non-small-cell lung cancer with EGFR mutation and will be moving to phase II (NCT03381274). [ABSTRACT FROM AUTHOR]

Cryptococcosis is a global invasive mycosis associated with significant morbidity and mortality. Cryptococcal antigen (CrAg) testing from serum and cerebrospinal fluid (CSF) has been regarded as a gold standard for early diagnosis. This study aimed to develop and validate a rapid and sensitive sandwich chemiluminescent magnetic microparticle immunoassay (CMIA) for quantitative detection of CrAg in sera. CMIA is based on magnetic beads modified with capture antibodies and biotinylated antibodies and Streptavidin-polyHRP, where biotinylated antibodies functioned as the recognition element and Streptavidin-polyHRP as the signal component. Assay parameters were first optimized, and then assay performances were evaluated. Under optimized conditions, the total runtime of the CMIA was 22 min. The assay had a wide linear range (2 –10,000 ng/mL) and high analytical sensitivity (0.24 ng/mL), together with acceptable reproducibility, accuracy, and stability. Besides, it exhibited no cross-reactivity with other pathogens. Importantly, the assay showed 92.91% (95% CI, 80.97–93.02%) overall qualitative agreement with a commercial ELISA kit in a retrospective cohort of 55 cases with confirmed cryptococcal infection, and 72 controls without evidence of invasive fungal disease (IFD). These results demonstrated that the present study paved a novel strategy for reliable quantitative detection of CrAg in sera. [ABSTRACT FROM AUTHOR]

Objective: Although human blood consists of the same basic parts (red blood cells, white blood cells, platelets, and plasma), there are a large variety of blood groups and types, each with its own different characteristics. The aim of this study to search the correlation between different types of blood groups and increase risk factor for type 2 diabetic mellitus disease. Methods: Blood is made up of several components, and all of these can be utilized to management a lot of different illness. What makes a blood type different is the combination of protein molecules called antigens and antibodies. A person's blood type is also considered to be inherited from the parents' genes. Diabetic mellitus type 2 is related with a type of a chronic illness that effect the trend of the cells in the body for receive glucose or the amount of insulin which synthesize in the pancreas, thus leads to an abnormal decrease or increase in the scale of glucose in the blood. Results: Blood type O had a low risk of diabetes for women with type A, and same for women with type A. Group AB, and low persent of type B, compared with blood group O, have poor chances of developing diabetes. Conclusions: The effect of blood types should be investigated in future clinical and epidemiological studies on diabetes, also there is a need for more research on the pathophysiological mechanism to explain why diabetes has people of group O have a low risk of developing type 2 diabetes. [ABSTRACT FROM AUTHOR]

Background: CA 19-9 is a commonly assessed tumor marker, considered characteristic of pancreatic ductal adenocarcinoma (PDAC) and biliary tract cancers; however, the positive predictive value of CA 19.9 is too low, and the usage of CA 19.9 as a screening tool in the healthy population remains controversial. Methods: The presented case illustrates a reversed diagnosis of highly elevated serum CA 19-9 levels in a 54-year-old female complaining of pain in the epigastric region, shortly after COVID-19 vaccination. Laboratory tests showed a significantly elevated level of the CA 19-9 marker (>12,000 U/mL, reference value: <37 U/mL) with normal pancreatic enzyme activity. The patient underwent imaging examination, which showed no abnormalities, except for increased pancreatic dimension and areas of fluid signal in the pancreas in magnetic resonance imaging (MRI), which may correspond to autoimmune pancreatitis (AIP). The patient remains asymptomatic with a recommendation for a follow-up MRI in 12 months. Results: A literature review conducted revealed multi-causal CA 19-9 increases above 1000 U/mL, including non-cancerous diseases of the lung, pancreas, liver, ovary, kidney, and others. The median concentration of CA 19-9 regardless of the cause of disease was 2810 U/mL (IQR ± 6895). The median CA 19-9 values in men and women were 3500 (IQR ± 10,050) and 2455 (IQR ± 3927), respectively, and differ significantly between the compared groups (p < 0.05). There was no difference between CA 19-9 values and the categorized cause of the increase. Conclusions: Conducting differential diagnosis, it should not be forgotten that most international guidelines recommend the use of CA 19-9 only in conjunction with pathology of pancreas in radiological imaging; however, even such a combination can point the diagnostic pathway in the wrong direction. A highly elevated CA 19-9 level, typically associated with PDAC, may be the result of benign disease including AIP related to COVID-19 vaccination. [ABSTRACT FROM AUTHOR]

Nanoparticles have been identified in numerous studies as effective antigen delivery systems that enhance immune responses. However, it remains unclear whether this enhancement is a result of increased antigen uptake when carried by nanoparticles or the adjuvanticity of the nanoparticle carriers. Consequently, it is important to quantify antigen uptake by dendritic cells in a manner that is free from artifacts in order to analyze the immune response when antigens are carried by nanoparticles. In this study, we demonstrated several scenarios (antigens on nanoparticles or inside cells) that are likely to contribute to the generation of artifacts in conventional fluorescence-based quantification. Furthermore, we developed the necessary assay for accurate uptake quantification. PLGA NPs were selected as the model carrier system to deliver EsxB protein (a Staphylococcus aureus antigen) in order to testify to the feasibility of the established method. The results showed that for the same antigen uptake amount, the antigen delivered by PLGA nanoparticles could elicit 3.6 times IL-2 secretion (representative of cellular immune response activation) and 1.5 times IL-12 secretion (representative of DC maturation level) compared with pure antigen feeding. The findings above give direct evidence of the extra adjuvanticity of PLGA nanoparticles, except for their delivery functions. The developed methodology allows for the evaluation of immune cell responses on an antigen uptake basis, thus providing a better understanding of the origin of the adjuvanticity of nanoparticle carriers. Ultimately, this research provides general guidelines for the formulation of nano-vaccines. [ABSTRACT FROM AUTHOR]