SARS-CoV-2 mRNA vaccination induces an antigen-specific T cell response correlating with plasma interferon-gamma in B cell depleted patients.

Emerging evidence is encouraging and suggests that a substantial proportion of patients without antibody responses (due to anti-CD20 therapy or other etiologies) to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) vaccines develop T cell responses. However, antigen-specific T cellular responses are notoriously difficult to assess clinically, given the lack of such assays under satisfactory CAP/CLIA regulation, and the laborious nature of the flow cytometric assessment. To evaluate the ability to apply a clinically feasible assay to measure T cellular responses to SARS-CoV-2 mRNA vaccination, we compared flow cytometric and enzyme-linked immunosorbent assay (ELISA) based assays in 24 participants treated with anti-CD20 therapy. T cellular activation (CD69 + CD137+ surface expression, i.e., activation induced markers [AIM]) and intracellular interferon gamma (INFγ) production via flow cytometry was compared to plasma Interferon Gamma Release Assay (IGRA) via ELISA. Plasma INFγ production measured by IGRA correlated with the percent of INFγ-producing AIM positive T cells, supporting the use of IGRA assay as a robust assessment of T cellular response to the SARS-CoV-2 vaccine for B-cell depleted patients that is clinically feasible, time efficient, and cost effective.

The need for fast and accurate detection of dermatomycosis.

Dermatomycosis of the hair, skin, or nails is one of the most common fungal infections worldwide. Beyond permanent damage to the affected area, the risk of severe dermatomycosis in immunocompromised people can be life-threatening. The potential risk of delayed or improper treatment highlights the need for a rapid and accurate diagnosis. However, with traditional methods of fungal diagnostics such as culture, a diagnosis can take several weeks. Alternative diagnostic technologies have been developed which allow for an appropriate and timely selection of an antifungal treatment, preventing nonspecific over-the-counter self-medication. Such techniques include molecular methods, such as polymerase chain reaction (PCR), real-time PCR, DNA microarray, next-generation sequencing, in addition to matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry. Molecular methods can help close the 'diagnostic gap' observed with traditional cultures and microscopy and allow for a rapid detection of dermatomycosis with increased sensitivity and specificity. In this review, advantages and disadvantages of traditional and molecular techniques are discussed, in addition to the importance of species-specific dermatophyte determination. Finally, we highlight the need for clinicians to adapt molecular techniques for the rapid and reliable detection of dermatomycosis infections and to reduce adverse events.

Dermatomycosis is one of the most common fungal infections worldwide. Traditional fungal diagnostics are limited and can take several weeks. Molecular techniques can detect dermatomycosis pathogens quickly and allow for species-specific identification which is important for treatment.

Serological Biomarkers and Their Detection in Autoimmune Bullous Skin Diseases.

Autoimmune bullous diseases (AIBDs) are a group of skin-related disorders that involve damage to structures maintaining cell-cell adhesion, such as desmosomes and hemidesmosomes. Key AIBDs include pemphigus related diseases, pemphigoid related conditions, acquired epidermolysis bullosa (EBA), and dermatitis herpetiformis (DH). Each group of conditions exhibits characteristic clinical lesion patterns and is associated with specific autoantibodies targeting epidermal and dermal structures involved in cell-cell adhesion and skin integrity. Pemphigus diseases primarily target desmoglein (Dsg) 3 and Dsg1 proteins but several non-Dsg autoantibodies have also been linked to pemphigus. Pemphigoid diseases typically target bullous pemphigoid (BP)180 and BP230; EBA is associated with antibodies directed against anti-type VII collagen and DH by IgA autoantibodies against tissue transglutaminase and deaminated gliadin. Investigation into the serological biomarkers found in AIBDs have allowed the development of diagnostic assessments (i.e. tissue antibody detection and serological testing) based on the unique autoantibody profiles of a particular disease group. The methods for the detection and quantification of disease-associated autoantibodies continue to evolve and improve.

Performance of the Euroimmun Aspergillus Antigen ELISA for the Diagnosis of Invasive Pulmonary Aspergillosis in Bronchoalveolar Lavage Fluid.

Invasive pulmonary aspergillosis (IPA) is a life-threatening disease that affects mainly immunocompromised hosts. Galactomannan testing from serum and bronchoalveolar lavage fluid (BALF) represents a cornerstone in diagnosing the disease. Here, we evaluated the diagnostic performance of the novel Aspergillus-specific galactomannoprotein (GP) enzyme-linked immunosorbent assay (ELISA; Euroimmun Medizinische Labordiagnostika) compared with the established Platelia Aspergillus GM ELISA (GM; Bio-Rad Laboratories) for the detection of Aspergillus antigen in BALF. Using the GP ELISA, we retrospectively tested 115 BALF samples from 115 patients with clinical suspicion of IPA and GM analysis ordered in clinical routine. Spearman's correlation statistics and receiver operating characteristics (ROC) curve analysis were performed. Optimal cutoff values were determined using Youden's index. Of 115 patients, 1 patient fulfilled criteria for proven IPA, 42 for probable IPA, 15 for putative IPA, 10 for possible IPA, and 47 did not meet criteria for IPA. Sensitivities and specificities for differentiating proven/probable/putative versus no IPA (possible excluded) were 74% and 96% for BALF GP and 90% and 96% for BALF GM at the manufacturer-recommended cutoffs. Using the calculated optimal cutoff value of 12 pg/mL, sensitivity and specificity of the BALF GP were 90% and 96%, respectively. ROC curve analysis showed an area under the curve (AUC) of 0.959 (95% confidence interval [CI] of 0.923 to 0.995) for the GP ELISA and an AUC of 0.960 (95% CI of 0.921 to 0.999) for the GM ELISA for differentiating proven/probable/putative IPA versus no IPA. Spearman's correlation analysis showed a strong correlation between the ELISAs (rho = 0.809, P < 0.0001). The GP ELISA demonstrated strong correlation and test performance similar to that of the GM ELISA and could serve as an alternative test for BALF from patients at risk for IPA.

Phosphorylated neurofilament heavy chain: a potential diagnostic biomarker in amyotrophic lateral sclerosis.

Neuroaxonal damage is a feature of various neurodegenerative diseases including amyotrophic lateral sclerosis (ALS). Phosphorylated neurofilament heavy chain (pNfH) is a cytoskeletal structural protein released as a result of axonal damage into the cerebrospinal fluid (CSF), and subsequently into the blood. Due to high specificity for neuronal cell damage, pNfH is advantageous over other biomarkers, for ALS disease identification. Here, we review the structure and function of neurofilaments and their role in detection of various neurodegenerative conditions. In addition, a retrospective meta-analysis was performed to depict the significance of pNfH as a valuable diagnostic and prognostic biomarker in ALS.

COVID-19: Testing Landscape Post-Infection, -Vaccination, and Future Perspectives.

On March 11, 2020, the World Health Organization declared the coronavirus disease 2019 (COVID-19) outbreak a global pandemic. Although molecular testing remains the gold standard for COVID-19 diagnosis, serological testing enables the evaluation of the immune response to severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection and vaccination, and can be used to assess community viral spread. This review summarizes and analyzes the current landscape of SARS-CoV-2 testing in the United States and includes guidance on both when and why it is important to use direct pathogen detection and/or serological testing. The usefulness of monitoring humoral and cellular immune responses in infected and vaccinated patients is also addressed. Finally, this review considers current challenges, future perspectives for SARS-CoV-2 testing, and how diagnostics are being adapted as the virus evolves.

First amyloid ß1-42 certified reference material for re-calibrating commercial immunoassays.

INTRODUCTION: Reference materials based on human cerebrospinal fluid were certified for the mass concentration of amyloid beta (Aß)1-42 (Aß42 ). They are intended to be used to calibrate diagnostic assays for Aß42 . METHODS: The three certified reference materials (CRMs), ERM-DA480/IFCC, ERM-DA481/IFCC and ERM-DA482/IFCC, were prepared at three concentration levels and characterized using isotope dilution mass spectrometry methods. Roche, EUROIMMUN, and Fujirebio used the three CRMs to re-calibrate their immunoassays. RESULTS: The certified Aß42 mass concentrations in ERM-DA480/IFCC, ERM-DA481/IFCC, and ERM-DA482/IFCC are 0.45, 0.72, and 1.22 µg/L, respectively, with expanded uncertainties (k = 2) of 0.07, 0.11, and 0.18 µg/L, respectively. Before re-calibration, a good correlation (Pearson's r > 0.97), yet large biases, were observed between results from different commercial assays. After re-calibration the between-assay bias was reduced to < 5%. DISCUSSION: The Aß42 CRMs can ensure the equivalence of results between methods and across platforms for the measurement of Aß42 .

The Development of New Diagnostic Tests for Neurologic Disorders in the Commercial Laboratory Environment.

Development of new diagnostic tests in a commercial laboratory for neurologic disorders is challenging. Development occurs in a highly regulated environment. Relevant research infrastructure may not be readily available in-house and may require outsourcing with additional management and costs. Clinically characterized specimens for validation of biomarkers for esoteric diseases may be difficult to acquire, and market size may be difficult to predict. More common diseases with heterogeneous subsets may require better clinical definition. Absence of guidelines may delay health provider acceptance of novel testing. Regulatory agency approval and categorization of tests affects validation requirements and impacts market acceptance and reimbursement.