Trajectories of the SARS-CoV-2 RNA load in patients with hematological malignancy.

OBJECTIVES: The higher risk of prolonged viral shedding in coronavirus disease (COVID-19) patients with hematological malignancies (HM) necessitates test-based de-isolation strategies. However, evidence to establish their appropriate isolation period is insufficient. This study investigated the factors affecting prolonged viral shedding and the requisite isolation period in these patients. METHODS: We retrospectively reviewed 14 COVID-19 patients with HM between January and April 2022, who were subjected to our test-based de-isolation strategy, followed by analysis of the viral load trajectory. The viral loads of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) were evaluated using the cycle threshold (Ct ) of the reverse-transcription quantitative polymerase chain reaction. The trajectories were classified according to the time-interval from COVID-19 onset to the attainment of Ct values >30. RESULTS: The median interval between onset and attainment of a Ct value >30 was 22 days. Five patients with mild or moderate COVID-19 without intense treatment histories achieved Ct values >30 within 20 days. The other nine patients needed more than 20 days, including three patients who did not meet this criterion during the observation period. CONCLUSIONS: The SARS-CoV-2 viral load trajectories in patients with HM can be stratified by treatment history for the underlying HM and severity of COVID-19.

Humoral response and safety of the BNT162b2 and mRNA-1273 COVID-19 vaccines in allogeneic hematopoietic stem cell transplant recipients: An observational study.

BACKGROUND: The effectiveness of mRNA COVID-19 vaccines and the optimal timing of vaccine administration in allogeneic hematopoietic stem cell transplantation (Allo-HSCT) recipients remains inadequately investigated. We examine the effectiveness and safety of mRNA COVID-19 vaccines in allo-HSCT recipients. METHOD: This prospective observational study included 44 allo-HSCT recipients and 38 healthy volunteers. The proportion of subjects acquiring anti-S1 IgG antibodies were considered as the primary endpoint. The occurrence of adverse events after vaccination and objective deterioration of chronic graft-versus-host disease (GVHD) were defined as secondary endpoints. In addition, we compared the geometric mean titers (GMT) of anti-S1 antibody titers in subgroups based on time interval between transplantation and vaccination. RESULTS: A humoral response to the vaccine was evident in 40 (91%) patients and all 38 healthy controls. The GMT of anti-S1 titers in patients and healthy controls were 277 (95% confidence interval [CI]: 120-643) BAU/mL and 532 (95% CI 400-708) BAU/mL, respectively. (p = 0.603). A short time interval between transplantation and vaccination (≤6 months) was associated with low anti-S1 IgG antibody titers. No serious adverse events and deterioration of chronic GVHD were observed. Only one case of new development of mild chronic GVHD was recorded. CONCLUSION: Messenger RNA COVID-19 vaccines induce humoral responses in allo-HSCT recipients and can be administered safely.

Regulation of HLTF-mediated PCNA polyubiquitination by RFC and PCNA monoubiquitination levels determines choice of damage tolerance pathway.

DNA-damage tolerance protects cells via at least two sub-pathways regulated by proliferating cell nuclear antigen (PCNA) ubiquitination in eukaryotes: translesion DNA synthesis (TLS) and template switching (TS), which are stimulated by mono- and polyubiquitination, respectively. However, how cells choose between the two pathways remains unclear. The regulation of ubiquitin ligases catalyzing polyubiquitination, such as helicase-like transcription factor (HLTF), could play a role in the choice of pathway. Here, we demonstrate that the ligase activity of HLTF is stimulated by double-stranded DNA via HIRAN domain-dependent recruitment to stalled primer ends. Replication factor C (RFC) and PCNA located at primer ends, however, suppress en bloc polyubiquitination in the complex, redirecting toward sequential chain elongation. When PCNA in the complex is monoubiquitinated by RAD6-RAD18, the resulting ubiquitin moiety is immediately polyubiquitinated by coexisting HLTF, indicating a coupling reaction between mono- and polyubiquitination. By contrast, when PCNA was monoubiquitinated in the absence of HLTF, it was not polyubiquitinated by subsequently recruited HLTF unless all three-subunits of PCNA were monoubiquitinated, indicating that the uncoupling reaction specifically occurs on three-subunit-monoubiquitinated PCNA. We discuss the physiological relevance of the different modes of the polyubiquitination to the choice of cells between TLS and TS under different conditions.

Early prediction of cytokine release syndrome by measuring phosphate and magnesium levels following chimeric antigen receptor T cell therapy.

Introduction: Cytokine release syndrome (CRS) is a life-threatening side effect of chimeric antigen receptor T (CAR-T) cell therapy. This study investigated whether serum inorganic phosphate (IP) and magnesium (Mg) levels are predictive markers of CRS development. Methods: This single-center retrospective cohort study enrolled 16 consecutive patients with diffuse large B-cell lymphoma who had received CAR-T cell therapy. Logistic regression models with generalized estimating equations were used to evaluate whether changes in IP and Mg levels from their baseline values were associated with the development of CRS within 48 hours. Results: Decreased IP and Mg levels from baseline (per 10% change) were associated with an increased CRS incidence (adjusted odds ratio 2.18 [95% confidence interval (CI), 1.31-3.62], 3.18 [95% CI, 1.57-6.44], respectively). Conclusions: Changes in IP and Mg concentrations within 48 hours may be useful predictive markers of CRS onset.

Efficacy of letermovir in HLA-haploidentical hematopoietic transplantation with posttransplant cyclophosphamide.

BACKGROUND: Cytomegalovirus reactivation (CMV-R) is a significant complication of allogeneic hematopoietic stem cell transplantation (allo-HCT), especially in human leukocyte antigen-haploidentical transplantation (haplo-HCT) with posttransplant cyclophosphamide (PTCy). Prophylactic letermovir (LTV) prevents CMV-R in patients undergoing allo-HCT. However, evidence regarding its use in haplo-HCTs with PTCy is limited. Therefore, we aimed to investigate the efficacy of prophylactic LTV in haplo-HCT with PTCy. METHODS: We retrospectively analyzed 52 patients seropositive for CMV who underwent haplo-HCT with PTCy at our institution between January 2015 and June 2021 and compared patients who received LTV prophylaxis (LTV group: n = 29) with those who did not receive prophylaxis for CMV (control group: n = 23). The primary endpoint was the 100-day cumulative CMV-R incidence. We used Gray's test and the Fine and Gray test to compare the two groups. RESULTS: The 100-day cumulative CMV-R incidence was lower in the LTV group than in the control group (17.2% vs 81.8%, p < 0.001). Multivariate analysis revealed that prophylactic LTV reduced the 100-day cumulative CMV-R incidence (hazard ratio: 0.17, 95% confidence interval: 0.06-0.44, p < 0.001). CONCLUSIONS: Prophylactic LTV effectively prevents CMV-R in patients undergoing haplo-HCT for PTCy.

Inhaled corticosteroids do not affect the antibody titer against the SARS-CoV-2 spike protein in BNT162b2 mRNA vaccinated patients.

OBJECTIVES: Oral corticosteroids reduce the antibody titer of the BNT162b2 mRNA vaccine against SARS-CoV-2. To date, the effect of inhaled corticosteroids on antibody titers is unknown. STUDY DESIGN: The design of this study is retrospective study. METHODS: We analyzed the relationship between the clinical features and total antibody titers against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein in 320 subjects who had never been infected with Coronavirus disease 2019 (COVID-19) and were vaccinated the second time with the BNT162b2 mRNA vaccine between October 1 to December 28, 2021. RESULTS: Of the 320 subjects, 205 were treated with inhaled corticosteroids. The median antibody titer of patients treated with inhaled corticosteroids was 572 U/mL, which was significantly higher than that of patients treated without inhaled corticosteroids (454U/mL, P = 0.00258). The median antibody titers of smokers, men, and patients aged 65 years and over, were 315.5 U/mL, 385 U/mL, and 425.5 U/mL, respectively. These results are significantly lower than those of patients who never smoked, women, and patients aged less than 64 years (582 U/mL [P < 0.0001], 682.5 U/mL [P < 0.0001], and 717 U/mL [P < 0.0001], respectively). The multivariate analysis revealed that females and age were independent antibody titer-reducing factors (P = 0.0001 and P < 0.0001, respectively). CONCLUSIONS: The use of inhaled corticosteroids did not reduce the antibody titer against SARS-CoV-2 spike protein. Clinicians should continue treatment with inhaled corticosteroids if indicated.