Immune Response after the Fourth Dose of SARS-CoV-2 mRNA Vaccine Compared to Natural Infection in Three Doses’ Vaccinated Solid Organ Transplant Recipients

Solid organ transplant recipients (SOTRs) show higher rates of COVID-19 breakthrough infection than the general population, and nowadays, vaccination is the key preventative strategy. Nonetheless, SOTRs show lower vaccine efficacy for the prevention of severe COVID-19. Moreover, the emergence of new SARS-CoV-2 variants of concern has highlighted the need to improve vaccine-induced immune responses by the administration of repeated booster doses. In this study, we analyzed the humoral and cellular responses in a cohort of 25 SOTRs, including 15 never-infected SOTRs who received the fourth dose of the mRNA vaccine and 10 SOTRs who contracted SARS-CoV-2 infection after the third dose. We analyzed the serum IgG and IgA levels through CLIA or ELISA, respectively, and the Spike-specific T cells by ELISpot assay. We report a significant increase in anti-Spike IgG and no differences in IgA secretion in both groups of patients before and after the booster dose or the natural infection. Still, we show higher IgA levels in recovered SOTRs compared to the fourth dose recipients. Conversely, we show the maintenance of a positive Spike-specific T-cell response in SOTRs who received the fourth dose, which, instead, was significantly increased in SOTRs who contracted the infection. Our results suggest that the booster, either through the fourth dose or natural infection, in vulnerable poor responder SOTRs, improves both humoral and cellular-specific immune responses against SARS-CoV-2.     

Albumin-based solution is the ideal post-thawing suspension medium for cord blood hematopoietic stem cells: A stability and proliferative evaluation

Background

Cryopreservation and thawing protocols represent key factors for the efficacy of cellular therapy products, such as hematopoietic stem cells (HSCs). While the HSC cryopreservation has already been standardized, the thawing procedures have been poorly studied. This study aimed to evaluate the thawing and washing protocol of cord blood (CB) derived HSCs or the HPC(CB), by selecting the optimal thawing solution and determining CD34+ cells' stability over time.

Study Design and Methods

Seven cryopreserved CB products were thawed, washed, and resuspended in three different solutions (10% Dextran40 in NaCl equally prepared with 5% human albumin; 5% human albumin in PBS/EDTA; and normal saline) and stored at 4°C (±2°C). Mononuclear cell (MNC) count, CD45+/CD34+ cell enumeration, and cell viability were tested at 0, 1, 2, 4, 6, 8, 12, 24, 36, and 48 h. The protocol with the selected solution was further validated on additional 10 CB samples. The above parameters and the colony-forming unit (CFU) assay were analyzed at time points 0, 2, 4, 6, and 8 h.

Results and Discussion

The results showed that the 5% human albumin was the most suitable thawing solution. MNCs were stable up to 4 h (p = 0.009), viable CD45+ cells were unstable even at 2 h (p = 0.013), and viable CD34+ cells were stable until 6 h (p = 0.019). The CFU assay proved the proliferative potential up to 8 h, although significantly decreased after 4 h (p = 0.013), and correlated with the viable CD34+ cell counts. We demonstrated that the post-thawed and washed HPC(CB) using 5% human albumin is stable for up to 4 h.     

A head-to-head observational cohort study on the efficacy and safety of monoclonal antibodies against calcitonin gene–related peptide for chronic and episodic migraine

Objective

To compare the effectiveness and safety of galcanezumab, fremanezumab, and erenumab for the treatment of chronic and episodic migraine, through real-world data.

Background

Monoclonal antibodies (mAbs) targeting the calcitonin gene–related peptide (CGRP) pathway have been tested extensively in several clinical trials for both episodic and chronic migraine, showing high effectiveness, safety, and tolerability; however, there are no prospective real-world studies intending to compare their efficacy and safety.

Methods

This is a prospective observational cohort study comparing the effectiveness and safety profiles of galcanezumab, fremanezumab, and erenumab for the treatment of chronic and episodic migraine. We enrolled 140 patients at the Headache Centre of University Federico II of Naples, with a history of multiple failed treatments with validated migraine preventatives. Framenezumab, erenumab, or galcanezumab were administered for 12 months. The mean monthly days with headache, Migraine Disability Assessment (MIDAS) score, and adverse events were evaluated during the run-in period and every 3 months by reviewing standardized paper patient headache diaries.

Results

We found a mean reduction of migraine monthly days from baseline of −12.0 (−9.8, −14.1) in the galcanezumab group, −12.3 (−10.2, −14.3) in the fremanezumab group, and −10.8 (−8.5, −13.1) in the erenumab group (for all, p < 0.001). We found a mean reduction of MIDAS score of −32.6 (−26.6, −38.5) in the galcanezumab group, −33.4 (−28.0, −38.9) in the fremanezumab group, and −29.2 (−23.0, −35.4) in the erenumab group (for all, p < 0.001). We found no significant differences between mAbs in the reduction of mean monthly days with headache and MIDAS score. We found a more rapid effect of galcanezumab and erenumab compared to fremanezumab in medication overuse headache patients after 3 months of treatment (−10.8 and −11.1 vs. −4.0 days; p = 0.029).

Conclusion

Our results confirm the therapeutic benefits of anti-CGRP mAbs. There is no evidence that suggests that one antibody may be superior to the others in terms of effectiveness, both in chronic and episodic patients.     

Predictors of clinical evolution of SARS-CoV-2 infection in hematological patients: A systematic review and meta-analysis

Main aim of this systematic review is to quantify the risk and identify predictors of clinical evolution of SARS-CoV-2 in hematological patients compared to different control populations. Two independent reviewers screened the literature assessing clinical outcomes of SARS-CoV-2 infection in adult patients with active hematological malignancies published up to June 2021. Primary outcome was COVID-19 related mortality, secondary outcomes were hospital and intensive-care admission, mechanical ventilation (MV), and thromboembolic events. Variables related to study setting, baseline patients' demographic, comorbidities, underlying hematological disease, ongoing chemotherapy, COVID-19 presentation, and treatments were extracted. A total of 67 studies including 10,061 hematological patients and 111,143 controls were included. Most of the studies were retrospective cohorts (51 studies, 76%) and only 19 (13%) provided data for a control group. A significant increased risk of clinical progression in the hematological population compared to the controls was found in terms of COVID-19 related mortality (OR, 2.12; 95% CI, 1.77–2.54), hospitalization (OR, 1.98; 95% CI, 1.15–3.43), intensive-care admission (OR, 1.77; 95% CI, 1.38–2.26), and MV (OR, 2.17; 95% CI, 1.71–2.75). The risk remained significantly higher in the subgroup analysis comparing hematological patients versus solid cancer. Meta-regression analysis of uncontrolled studies showed that older age, male sex, and hypertension were significantly related to worse clinical outcomes of COVID-19 in hematological population. Older age and hypertension were found to be associated also to thromboembolic events. In conclusion, hematological patients have a higher risk of COVID-19 clinical progression compared to both the general population and to patients with solid cancer.