Since the onset of the COVID-19 pandemic, the medical field has been forced to apply the basic knowledge of immunology with the most up-to-date SARS-CoV-2 findings and translate it to the population of the whole world in record time. Following the infection with the viral antigen, adaptive immune responses are activated mainly by viral particle encounters with the antigen-presenting cells or B cell receptors, which induce further biological interactions to defend the host against the virus. After the infection has been warded off, the immunological memory is developed. The SARS-CoV cellular immunity has been shown to persist even 17 years after the infection, despite the undetectable humoral component. Similar has been demonstrated for the SARS-CoV-2 T cell memory in a shorter period by assessing interferon-gamma levels when heparinized blood is stimulated with the virus-specific peptides. T cells also play an irreplaceable part in a humoral immune reaction as the backbone of a cellular immune response. They both provide the signals for B cell activation and the maturation, competence, and memory of the humoral response. B cell production of IgA was shown to be of significant influence in mediating mucosal immunity as the first part of the defense mechanism and in the development of nasal vaccines. Here, we interpret the recent SARS-CoV-2 available research, which encompasses the significance and the current understanding of adaptive immune activity, and compare it among naive, exposed, and vaccinated blood donors. Our recent data showed that those who recovered from COVID-19 and those who are vaccinated with EMA-approved vaccines had a long-lasting cellular immunity. Additionally, we analyze the humoral responses in immunocompromised patients and memory mediated by cellular immunity and the impact of clonality in the SARS-CoV-2 pandemic regarding breakthrough infections and variants of concern, both B.1.617.2 (Delta) and B.1.1.529 (Omicron) variants.

With the insufficient satisfaction rates and high cost of operative treatment for osteoarthritis (OA), alternatives have been sought. Furthermore, the inability of current medications to arrest disease progression has led to rapidly growing clinical research relating to mesenchymal stem cells (MSCs). The availability and function of MSCs vary according to tissue source. The three primary sources include the placenta, bone marrow, and adipose tissue, all of which offer excellent safety profiles. The primary mechanisms of action are trophic and immunomodulatory effects, which prevent the further degradation of joints. However, the function and degree to which benefits are observed vary significantly based on the exosomes secreted by MSCs. Paracrine and autocrine mechanisms prevent cell apoptosis and tissue fibrosis, initiate angiogenesis, and stimulate mitosis via growth factors. MSCs have even been shown to exhibit antimicrobial effects. Clinical results incorporating clinical scores and objective radiological imaging have been promising, but a lack of standardization in isolating MSCs prevents their incorporation in current guidelines.

Recent studies have highlighted the underestimated importance of the cellular immune response after the emergence of variants of concern (VOCs) of SARS-CoV-2, and the significantly reduced neutralizing power of antibody titers in individuals with previous SARS-CoV-2 infection or vaccination. Our study included 303 participants who were tested at St. Catherine Specialty Hospital using the Quan-T-Cell SARS-CoV-2 in combination with the Quan-T-Cell ELISA (Euroimmun Medizinische Labordiagnostika, Lübeck, Germany) for the analysis of IFN-γ concentration, and with Anti-SARS-CoV-2 QuantiVac ELISA IgG (Euroimmun Medizinische Labordiagnostika, Lübeck, Germany) for the detection of human antibodies of the immunoglobulin class IgG against the S1 domain of the SARS-CoV-2 spike protein. The statistical analysis showed a significant difference in the concentration of IFN-γ between reinfected participants and those without infection (p = 0.012). Participants who were not infected or reinfected with SARS-CoV-2 after vaccination and/or previous SARS-CoV-2 infection had a significantly higher level of cellular immunity. Furthermore, in individuals without additional vaccination, those who experienced infection/reinfection had significantly lower levels of IFN-γ compared to uninfected participants (p = 0.016). Our findings suggest a long-lasting effect of cellular immunity, measured by IFN-γ concentrations, which plays a key role in preventing infections and reinfections after the emergence of SARS-CoV-2 variants of concern.

AimTo assess the prevalence of actionable pharmacogenetic interventions in patients who underwent pharmacogenetic testing with a multi-gene panel. MethodsWe retrospectively reviewed single-center electronic health records. A total of 319 patients were enrolled who underwent pharmacogenomic testing with the RightMed test panel using TaqMan quantitative real-time PCR method and copy number variation analysis to determine the SNPs in the 27 target genes. ResultsActionable drug-gene pairs were found in 235 (73.7%) patients. Relevant guidelines on genotype-based prescribing were available for 133 (56.7%) patients at the time of testing. Based on the patients' genotype, 139 (43.6%) patients were using at least one drug with significant pharmacogenetic interactions. ConclusionTwo out of three patients had at least one drug-gene pair in their therapy. Further studies should assess the clinical effectiveness of integrating pharmacogenomic data into patients' electronic health records.

Knee osteoarthritis (KOA) is one of the most common musculoskeletal disorders. Much progress has been made in regenerative medicine for the symptomatic treatment of KOA, including products containing stromal vascular fraction (SVF) and platelet-rich plasma (PRP). The aim of this study was to evaluate clinical and radiological findings after the application of autologous conditioned adipose tissue (ACA) and leukocyte-poor PRP (LP-PRP) in patients with mild to moderate KOA. A total of 16 patients (eight male and eight female) with changes related to KOA on the magnetic resonance imaging (MRI), but without severe osteophytosis, full-thickness cartilage loss, or subchondral bone involvement were included in this study. Patients received an intraarticular, ultrasound-guided injection of ACA and LP-PRP. Clinical scores, including a visual analog scale for pain (VAS), Knee Injury and Osteoarthritis Outcome Score (KOOS), and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were evaluated at baseline and at the three and six month follow-ups showing a statistically significant improvements at three and six months post-intervention. Furthermore, the delayed gadolinium-enhanced MRI of the cartilage (dGEMRIC) indices were evaluated at baseline and at the three and six month follow-ups showing no significant changes after treatment with ACA and LP-PRP, which were actually equal to the dGEMRIC indices measured in the control group (hyaluronic acid applied in contralateral knees without osteoarthritis). ACA with LP-PRP presents a viable minimally invasive therapeutic option for the clinical improvement of mild to moderate KOA. However, MFAT produced by different systems is likely to differ in cellular content, which can directly affect the paracrine effect (cytokine secretion) of mesenchymal stem cells and consequently the regeneration process.