Analysis of immune responses in CLL patients after heterologous COVID-19 vaccination

Patients with chronic lymphocytic leukemia (CLL) treated with B-cell pathway inhibitors and anti-CD20 antibodies exhibit low humoral response rates following SARS-CoV-2 vaccination. To investigate this observation, a prospective single-institution study was conducted comparing peripheral blood mononuclear cell transcriptional response with antibody and T cell response rates following heterologous BNT162b2/ChAdOx1 vaccination of 15 CLL/SLL patients. Two-dose antibody response rate was 40%, increasing to 53% after booster. Patients on Bruton tyrosine kinase inhibitor (BTKi), venetoclax ± anti-CD20 antibody within 12 months of vaccination, responded inferiorly to those under BTKi alone. The two-dose T cell response rate was 80%, increasing to 93% after booster. Key transcriptional findings were that interferon-mediated signaling activation including activation of the JAK-STAT pathway generally occurred within days of vaccination but was independent from the magnitude of the antibody response. Increasing counts of IGHV genes were associated with B-cell reconstitution and improved humoral response rate in the vaccinated patients. T cell responses in CLL patients appeared independent of treatment status while higher humoral response rate was associated with BTKi treatment and B-cell reconstitution. Boosting was particularly effective when intrinsic immune status was improved by CLL-treatment. Limitations included study of a relatively small cohort receiving different treatments and vaccination schedules.

Analysis of immune responses in patients with CLL after heterologous COVID-19 vaccination.

Patients with chronic lymphocytic leukemia (CLL) treated with B-cell pathway inhibitors and anti-CD20 antibodies exhibit low humoral response rates following SARS-CoV-2 vaccination. To investigate this observation, a prospective single-institution study was conducted comparing peripheral blood mononuclear cell transcriptional response with antibody and T-cell response rates following heterologous BNT162b2/ChAdOx1 vaccination of 15 patients with CLL/small lymphocytic lymphoma (SLL). Two-dose antibody response rate was 40%, increasing to 53% after booster. Patients on Bruton tyrosine kinase inhibitor (BTKi) and venetoclax ± anti-CD20 antibody within 12 months of vaccination responded inferiorly compared with those under BTKi alone. The 2-dose-T-cell response rate was 80%, which increased to 93% after the booster dose. Key transcriptional findings were that interferon-mediated signaling activation including activation of the JAK-STAT pathway generally occurred within days of vaccination, but was independent from the magnitude of the antibody response. Increasing counts of IGHV genes were associated with B-cell reconstitution and improved humoral response rate in the vaccinated patients. T-cell responses in patients with CLL appeared independent of treatment status, whereas higher humoral response rate was associated with BTKi treatment and B-cell reconstitution. Boosting was particularly effective when intrinsic immune status was improved by CLL treatment. Limitations included studying a relatively small cohort, with different treatments and vaccination schedules.

Heterologous ChAdOx1-BNT162b2 vaccination in Korean cohort induces robust immune and antibody responses that includes Omicron.

Heterologous ChAdOx1-BNT162b2 vaccination induces a stronger immune response than BNT162b2-BNT162b2. Here, we investigated the molecular transcriptome, germline allelic variants of immunoglobulin loci, and anti-Omicron antibody levels in 46 office and lab workers from the Republic of Korea following ChAdOx1-BNT162b2 vaccination. Anti-spike-specific IgG antibody levels against the ancestral SARS-CoV-2 strain increased from 70 AU/ml to 14,000 AU/ml to 142,000 AU/ml one, three and seven days following the second vaccination. Titers against VOC, including Omicron, were two-fold to three-fold lower, yet higher than those measured following BNT162b2-BNT162b2 vaccination. RNA-seq of peripheral immune cells demonstrated activation of interferon pathways with increased IGHV clonal transcripts encoding neutralizing antibodies. scRNA-seq revealed enriched B cell and CD4+ T cell responses in both ChAdOx1-BNT162b2 and BNT162b2-BNT162b2 recipients, but a stronger clonal expansion of memory B cells with ChAdOx1-BNT162b2. In summary, heterologous ChAdOx1-BNT162b2 provides an innate and adaptive immune response that exceeds homologous BNT162b2 vaccination.

Simultaneous detection of SARS-CoV-2 and identification of spike D614G mutation using point-of-care real-time polymerase chain reaction.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is associated with high mortality and infectivity rates in humans since its emergence. Analysis using high-accuracy real-time polymerase chain reaction (PCR) is recommended for the detection of general respiratory viruses including SARS-CoV-2, but it takes a long time (e.g. ~ 6 h); moreover, on-site diagnosis is difficult owing to the need for skilled technicians and advanced laboratory facilities. Currently, the importance of point-of-care testing (POCT) is being emphasized for the rapid detection of SARS-CoV-2. Here, we developed a multiplex real-time reverse transcription PCR (rRT-PCR) analysis that not only detects SARS-CoV-2 but also D614G strains with higher contagiousness than wild types among SARS-CoV-2 mutants using probe-based rRT-PCR. Moreover, this method was applied to portable PCR equipment capable of POCT to confirm high detection sensitivity and specificity. Multiple assays were possible with fluorescence labeling of individual probes. Furthermore, using a microfluidic chip-based point-of-care testing rRT-PCR platform, detection time was reduced by more than half compared with the commonly used detection system. This demonstrates that our assay has 100% of high sensitivity and specificity and could thus aid in the rapid and simple screening of SARS-CoV-2 carrying the mutation. We present a rapid detection method for mutations in SARS-CoV-2.

POCT Detection of 14 Respiratory Viruses Using Multiplex RT-PCR.

Over the past 6 years, acute respiratory infections have constituted an average of more than 70,000 cases in South Korea. It results in a high mortality rate in infants and the elderly with weak immunity. There are several types of respiratory viruses that invade the human respiratory tract and cause infectious disease. Reverse transcription PCR (RT-PCR) is mainly used for respiratory virus detection owing to its high sensitivity and reproducibility. In response, a multiplex real-time RT-PCR (rRT-PCR) assay was developed for the detection of influenza A and B viruses, parainfluenza viruses 1-4 (PIV1-4), human metapneumovirus, adenovirus, human rhinovirus, respiratory syncytial virus (RSV), and SARS-CoV-2. Detection ability of RT-PCR assay was confirmed by applying it to a portable device capable of point-of-care testing (POCT). Amplicons were synthesized using primer pairs and probe sets designed for each target virus, and a standard curve was constructed to confirm the limit of detection. An experiment using nasopharyngeal swab samples was conducted to understand the field applicability of the rRT-PCR assay. Detection was confirmed in most samples. This study demonstrated that rapid and accurate detection results can be obtained using the multiplex rRT-PCR based POC test, and that it is possible to detect 14 types of respiratory viruses that are generally difficult to distinguish at the same time, enabling timely treatment. Furthermore, we expect that the portable PCR device can significantly reduce the processing procedure of clinical samples before testing, which is the main disadvantage of common RT-PCR tests and can help reduce costs.