The Middle East respiratory syndrome coronavirus (MERS-CoV) causes a highly lethal pneumonia. MERS was recently identified as a candidate for vaccine development, but most efforts focus on antibody responses, which are often transient after CoV infections. CoV-specific T cells are generally long-lived, but the virus-specific T cell response has not been addressed in MERS patients. We obtained peripheral blood mononuclear cells and/or sera from 21 MERS survivors. We detected MERS-CoV–specific CD4⁺ and CD8⁺ T cell responses in all MERS survivors and demonstrated functionality by measuring cytokine expression after peptide stimulation. Neutralizing (PRNT₅₀) antibody titers measured in vitro predicted serum protective ability in infected mice and correlated with CD4⁺ but not CD8⁺ T cell responses; patients with higher PRNT₅₀ and CD4⁺ T cell responses had longer intensive care unit stays and prolonged virus shedding and required ventilation. Survivors with undetectable MERS-CoV–specific antibody responses mounted CD8⁺ T cell responses comparable with those of the whole cohort. There were no correlations between age, disease severity, comorbidities, and virus-specific CD8⁺ T cell responses. In conclusion, measurements of MERS-CoV–specific T cell responses may be useful for predicting prognosis, monitoring vaccine efficacy, and identifying MERS patients with mild disease in epidemiological studies and will complement virus-specific antibody measurements.

Electronic immunosensors are indispensable tools for diagnostics, particularly in scenarios demanding immediate results. Conventionally, these sensors rely on the chemical immobilization of antibodies onto electrodes. However, globular proteins tend to adsorb and unfold on these surfaces. Therefore, self‐assembled monolayers (SAMs) of thiolated alkyl molecules are commonly used for indirect gold–antibody coupling. Here, a limitation associated with SAMs is revealed, wherein they curtail the longevity of protein sensors, particularly when integrated into the state‐of‐the‐art transducer of organic bioelectronics—the organic electrochemical transistor. The SpyDirect method is introduced, generating an ultrahigh‐density array of oriented nanobody receptors stably linked to the gold electrode without any SAMs. It is accomplished by directly coupling cysteine‐terminated and orientation‐optimized spyTag peptides, onto which nanobody‐spyCatcher fusion proteins are autocatalytically attached, yielding a dense and uniform biorecognition layer. The structure‐guided design optimizes the conformation and packing of flexibly tethered nanobodies. This biolayer enhances shelf‐life and reduces background noise in various complex media. SpyDirect functionalization is faster and easier than SAM‐based methods and does not necessitate organic solvents, rendering the sensors eco‐friendly, accessible, and amenable to scalability. SpyDirect represents a broadly applicable biofunctionalization method for enhancing the cost‐effectiveness, sustainability, and longevity of electronic biosensors, all without compromising sensitivity.

Various studies have shown that SARS-CoV-2 is a highly immunogenic virus. It is known that different types of immunogenic viral pathogens could trigger the formation of HLA antibodies. Therefore, there is a concern that the SARS-CoV-2 could also induce the development of HLA antibodies in volunteers, who donate convalescent plasma after their recovery from COVID-19. HLA antibodies have been identified as the main cause for transfusion-related acute lung injury (TRALI), a well-documented life-threatening complication of transfusions. The TRALI risk could be high in COVID-19 patients who need convalescent plasma, as such patients usually have already an impaired respiratory system affected by the SARS-CoV-2 infection. In this study, we screened 34 convalescent plasma donors on the presence of antibodies against HLA class I and II antigens. All included donors have no any history of sensitization events such as blood transfusions, pregnancy, or previous transplants. We found a high rate of HLA antibody formation in convalescent plasma donors. The frequency of positivity for HLA antibodies for class I, class II, class I and II, and the overall reactivity was 23%, 31%, 46%, and 76%, respectively. The presented data suggest a closed correlation between SARS-CoV-2 virus infection and the development of HLA antibodies in recovered convalescent plasma donors. This finding might have the potential to reduce the risk of TRALI and mortality rate in COVID-19 patients by implementing HLA diagnostic strategies before the administration of convalescent plasma.

RNA viruses, including SARS-CoV-2, rely on genetic mutation as a major evolutionary mechanism, leading to the emergence of variants. Organ transplant recipients (OTRs) may be particularly vulnerable to such mutations, making it crucial to monitor the spread and evolution of SARS-CoV-2 in this population. This cohort study investigated the molecular epidemiology of SARS-CoV-2 by comparing the SARS-CoV-2 whole genome, demographic characteristics, clinical conditions, and outcomes of COVID-19 illness among OTRs (n = 19) and non-OTRs with (n = 38) or without (n = 30) comorbid conditions. Most patients without comorbidities were female, whereas most OTRs were male. Age varied significantly among the three groups: patients with comorbidities were the oldest, and patients without comorbidities were the youngest. Whole-genome sequencing revealed that OTRs with mild disease had higher numbers of unusual mutations than patients in the other two groups. Additionally, OTRs who died had similar spike monoclonal antibody resistance mutations and 3CLpro mutations, which may confer resistance to nirmatrelvir, ensitrelvir, and GC37 therapy. The presence of those unusual mutations may impact the severity of COVID-19 illness in OTRs by affecting the virus’s ability to evade the immune system or respond to treatment. The higher mutation rate in OTRs may also increase the risk of the emergence of new virus variants. These findings highlight the importance of monitoring the genetic makeup of SARS-CoV-2 in all immunocompromised populations and patients with comorbidity.

Timely and accurate diagnosis of respiratory infections is complicated by the symptomatic overlap between highly transmissible pathogens such as respiratory syncytial virus (RSV), influenza A (IAV), and influenza B (IBV), highlighting the need for rapid and reliable diagnostics. Here, we report a time‐multiplexed nanobody‐functionalized organic electrochemical transistor (OECT) biosensor for the sensitive detection of RSV, IAV, and IBV directly from unprocessed saliva samples. The platform integrates arrays of nanobody‐functionalized gate electrodes that are exposed in parallel to a single sample and sequentially addressed through a shared transistor channel. We characterize nine previously reported nanobodies and immobilize the best‐performing ones using an oriented SpyDirect self‐assembly strategy. The nanobody‐functionalized gate electrodes are paired with a high‐performance p‐type organic mixed ionic‐electronic conductor channel, enabling efficient signal transduction. The sensor achieves a limit of detection of ca. 1 f m and identifies viral targets within 15 min, without sample preprocessing. In a clinical validation using 17 samples, the platform demonstrated 100% specificity, 86.7% sensitivity, and 88.2% overall accuracy. By combining highly specific nanobodies, a high‐gain transducer, customized surface pre‐treatment, and a time‐multiplexed multi‐gate architecture, this approach provides a scalable and user‐friendly platform for point‐of‐care virus detection.

Many uncertainties exist regarding COVID-19 vaccination in patients undergoing treatment for hematological malignancies. We intend the illustrate the various types of COVID-19 vaccine currently in use and their mechanism of action. We have complied, recommendations for COVID-19 vaccination in patients suffering with specific hematological malignancies and those undergoing HCT and CAR-T cell therapy in this review. We have also discussed the available safety data for COVID-19 vaccination in the immunocompromised population.