An outbreak of severe acute respiratory coronavirus virus 2 (SARS-CoV-2) infections among hospital personnel with high mRNA vaccine uptake

Real-world studies have demonstrated impressive effectiveness of the BNT162b2 COVID-19 vaccine in preventing symptomatic and asymptomatic SARS-CoV-2 infection. We describe an outbreak of SARS-CoV-2 infections in a hospital with high vaccine uptake. We found a low secondary attack rate (7%), suggesting low infectivity of vaccinated persons with vaccine breakthrough SARS-CoV-2 infections.

Comparison of matched formalin-fixed paraffin embedded and fresh frozen meningioma tissue reveals bias in proteomic profiles

Tissue biopsies are most commonly archived in a paraffin block following tissue fixation with formaldehyde (FFPE) or as fresh frozen tissue (FFT). While both methods preserve biological samples, little is known about how they affect the quantifiable proteome. We performed a 'bottom-up' proteomic analysis (N = 20) of short and long-term archived FFPE surgical samples of human meningiomas and compared them to matched FFT specimens. FFT facilitated a similar number of proteins assigned by MetaMorpheus compared with matched FFPE specimens (5378 vs. 5338 proteins, respectively (p = 0.053), regardless of archival time. However, marked differences in the proteome composition were apparent between FFPE and FFT specimens. Twenty-three percent of FFPE-derived peptides and 8% of FFT-derived peptides contained at least one chemical modification. Methylation and formylation were most prominent in FFPE-derived peptides (36% and 17% of modified FFPE peptides, respectively) while, most of phosphorylation and iron modifications appeared in FFT-derived peptides (p < 0.001). A mean 14% (± 2.9) of peptides identified in FFPE contained at least one modified Lysine residue. Importantly, larger proteins were significantly overrepresented in FFT specimens, while FFPE specimens were enriched with smaller proteins.

Association of a Third Dose of BNT162b2 Vaccine With Incidence of SARS-CoV-2 Infection Among Health Care Workers in Israel

IMPORTANCE

Administration of a BNT162b2 booster dose (Pfizer-BioNTech) to fully vaccinated individuals aged 60 years and older was significantly associated with lower risk of SARS-CoV-2 infection and severe illness. Data are lacking on the effectiveness of booster doses for younger individuals and health care workers.

OBJECTIVE

To estimate the association of a BNT162b2 booster dose with SARS-CoV-2 infections among health care workers who were previously vaccinated with a 2-dose series of BNT162b2.

DESIGN, SETTING, AND PARTICIPANTS

This was a prospective cohort study conducted at a tertiary medical center in Tel Aviv, Israel. The study cohort included 1928 immunocompetent health care workers who were previously vaccinated with a 2-dose series of BNT162b2, and had enrolled between August 8 and 19, 2021, with final follow-up reported through September 20, 2021. Screening for SARS-CoV-2 infection was performed every 14 days. Anti-spike protein receptor binding domain IgG titers were determined at baseline and 1 month after enrollment. Cox regression with time-dependent analysis was used to estimate hazard ratios of SARS-CoV-2 infection between booster-immunized status and 2-dose vaccinated (booster-nonimmunized) status.

EXPOSURES

Vaccination with a booster dose of BNT162b2 vaccine.

MAIN OUTCOMES AND MEASURES

The primary outcome was SARS-CoV-2 infection, as confirmed by reverse transcriptase-polymerase chain reaction.

RESULTS

Among 1928 participants, the median age was 44 years (IQR, 36-52 years) and 1381 were women (71.6%). Participants completed the 2-dose vaccination series a median of 210 days (IQR, 205-213 days) before study enrollment. A total of 1650 participants (85.6%) received the booster dose. During a median follow-up of 39 days (IQR, 35-41 days), SARS-CoV-2 infection occurred in 44 participants (incidence rate, 60.2 per 100 000 person-days); 31 (70.5%) were symptomatic. Five SARS-CoV-2 infections occurred in booster-immunized participants and 39 in booster-nonimmunized participants (incidence rate, 12.8 vs 116 per 100 000 person-days, respectively). In a time-dependent Cox regression analysis, the adjusted hazard ratio of SARS-CoV-2 infection for booster-immunized vs booster-nonimmunized participants was 0.07 (95% CI, 0.02-0.20).

CONCLUSIONS AND RELEVANCE

Among health care workers at a single center in Israel who were previously vaccinated with a 2-dose series of BNT162b2, administration of a booster dose compared with not receiving one was associated with a significantly lower rate of SARS-CoV-2 infection over a median of 39 days of follow-up. Ongoing surveillance is required to assess durability of the findings.

Establishing and sustaining a biorepository network in Israel: challenges and progress

Over the past 5 years, using European and North American biobanks as models, the grass-roots establishment of independently operating biobanks has occurred virtually simultaneously in large Israeli teaching hospitals. The process of establishing a national biorepository network in Israel has progressed slowly, sustained mainly by a few proponents working together on a personal level. Slow progress has been due to limited funding and the lack of a legal framework specific to biobanking activities. Recently, due to increasing pressure from the scientific community, the government has earmarked funds for a national biorepository network, and the structure is now being established. In forming a network, Israel's biobanks face certain difficulties, particularly lack of support. Additional challenges include harmonization of standard operating procedures, database centralization, and use of a common informed consent form. In this article, we highlight some of the issues faced by Israel's biobank managers in establishing and sustaining a functional biobank network, information that could provide guidance for other small countries with limited resources.

The origin of human mesenchymal stromal cells dictates their reparative properties

Background

Human mesenchymal stromal cells (hMSCs) from adipose cardiac tissue have attracted considerable interest in regard to cell‐based therapies. We aimed to test the hypothesis that hMSCs from the heart and epicardial fat would be better cells for infarct repair.

Methods and Results

We isolated and grew hMSCs from patients with ischemic heart disease from 4 locations: epicardial fat, pericardial fat, subcutaneous fat, and the right atrium. Significantly, hMSCs from the right atrium and epicardial fat secreted the highest amounts of trophic and inflammatory cytokines, while hMSCs from pericardial and subcutaneous fat secreted the lowest. Relative expression of inflammation‐ and fibrosis‐related genes was considerably higher in hMSCs from the right atrium and epicardial fat than in subcutaneous fat hMSCs. To determine the functional effects of hMSCs, we allocated rats to hMSC transplantation 7 days after myocardial infarction. Atrial hMSCs induced greatest infarct vascularization as well as highest inflammation score 27 days after transplantation. Surprisingly, cardiac dysfunction was worst after transplantation of hMSCs from atrium and epicardial fat and minimal after transplantation of hMSCs from subcutaneous fat. These findings were confirmed by using hMSC transplantation in immunocompromised mice after myocardial infarction. Notably, there was a correlation between tumor necrosis factor‐α secretion from hMSCs and posttransplantation left ventricular remodeling and dysfunction.

Conclusions

Because of their proinflammatory properties, hMSCs from the right atrium and epicardial fat of cardiac patients could impair heart function after myocardial infarction. Our findings might be relevant to autologous mesenchymal stromal cell therapy and development and progression of ischemic heart disease.

Abstract 009: Cardiac Human Mesenchymal Stromal Cells from Patients with Ischemic Heart Disease are Proinflammatory and Impair Recovery after Myocardial Infarction in Rat

Introduction: Human mesenchymal stromal cells (hMSCs) from adipose cardiac tissue have attracted considerable interest for cell-based therapies. However, the best source of hMSCs for infarct repair is still unknown.

Hypothesis: We aimed to test the hypothesis that, because of their proximity to the heart, hMSCs from the heart and epicardial fat would be better cells for infarct repair.

Methods and Results: We isolated and grew hMSCs from patients with ischemic heart disease (IHD) from four different sources: 1) epicardial fat 2) pericardial fat 3) subcutaneous fat and 4) the right atrium. hMSCs from the right atrium and epicardial fat secreted the highest amounts of trophic and inflammatory cytokines, while hMSCs from pericardial and subcutaneous fat secreted the lowest (p<0.05, n=5-6 per source). Subsequently, the greatest angiogenic effect was induced with conditioned medium from atrium and epicardial fat hMSCs, by tube formation assay. To determine the effect of hMSCs in vivo , we allocated rats to hMSC transplantation 7 days after myocardial infarction (MI) (n=8-10 per group). Atrial hMSCs induced the highest number of vessels in the infarct, together with the highest inflammation score and macrophage accumulation 27 days after their injection. However, left ventricular (LV) dysfunction was worst after therapy with atrium and epicardial fat hMSCs, and minimal after subcutaneous fat hMSC therapy. Notably, there was a correlation between levels of tumor necrosis factor-α and hepatocyte growth factor, in vitro , and post-transplantation LV systolic dilatation. These surprising findings were supported by gene expression analysis in hMSCs from different sources of a patient with IHD. We found that the relative expression of inflammation and fibrosis-related genes was considerably higher in hMSCs from the right atrium and epicardial fat than in subcutaneous fat hMSCs.

Conclusions: The origin of hMSCs affects their reparative and immunomodulatory properties. Because of their pro-inflammatory properties, hMSCs from the right atrium and epicardial fat of IHD patients could impair heart function after MI. Our findings might be relevant to autologous MSC therapy and pathogenesis and progression of IHD.