Etablierung der PCR-basierten SARS-CoV-2-Testung im Hochdurchsatz.

Timely identification and isolation of affected individuals is one of the most important factors to control spreading of the newly emerged SARS-CoV-2. Consequently, it is crucial to maintain sufficient sample capacities in diagnostic laboratories. Here, we present a high-through-put approach for PCR-based SARS-CoV-2 testing. The implementation of sample pooling reduces costs and workload, especially in times with low population prevalence.

Individual HLA-A, -B, -C, and -DRB1 Genotypes Are No Major Factors Which Determine COVID-19 Severity.

HLA molecules are key restrictive elements to present intracellular antigens at the crossroads of an effective T-cell response against SARS-CoV-2. To determine the impact of the HLA genotype on the severity of SARS-CoV-2 courses, we investigated data from 6,919 infected individuals. HLA-A, -B, and -DRB1 allotypes grouped into HLA supertypes by functional or predicted structural similarities of the peptide-binding grooves did not predict COVID-19 severity. Further, we did not observe a heterozygote advantage or a benefit from HLA diplotypes with more divergent physicochemical peptide-binding properties. Finally, numbers of in silico predicted viral T-cell epitopes did not correlate with the severity of SARS-CoV-2 infections. These findings suggest that the HLA genotype is no major factor determining COVID-19 severity. Moreover, our data suggest that the spike glycoprotein alone may allow for abundant T-cell epitopes to mount robust T-cell responses not limited by the HLA genotype.

CCR5Δ32 mutations do not determine COVID-19 disease course.

OBJECTIVES: To determine the impact of the 32 bp deletion (CCR5Δ32) in the coding region of the C-C chemokine receptor 5 (CCR5) on the risk of contracting SARS-CoV-2 and severe COVID-19. METHODS: Cross-sectional study among stem cell donors registered with DKMS in Germany. Genetic information was linked to self-reported COVID-19 outcome data. Multivariable regression models were fitted to determine the risk of contracting SARS-CoV-2, severe respiratory tract infection (RTI) and respiratory hospitalization. RESULTS: CCR5 information was available for 110 544 donors who were tested at least once for SARS-CoV-2; 5536 reported SARS-CoV-2 infection. For 4758 donors, the COVID-19 disease course was fully evaluable; 498 reported no symptoms, 1227 described symptoms of severe respiratory tract infection, of whom 164 required respiratory hospitalization. The distribution of CCR5Δ32 genotypes (homozygous wild-type vs CCR5Δ32 present) did not differ significantly between individuals with or without SARS-CoV-2 infection (odds ratio (OR) 0.96, 95% CI 0.89-1.03, P = 0.21) nor between individuals with or without symptomatic infection (OR 1.13, 95% CI 0.88-1.45, P = 0.32), severe RTI (OR 1.03, 95% CI 0.88-1.22, P = 0.68) or respiratory hospitalization (OR 1.16, 95% CI 0.79-1.69, P = 0.45). CONCLUSIONS: Our data implicate that CCR5Δ32 mutations do not determine the risk of SARS-CoV-2 infections nor the disease course. TRIAL REGISTRATION: We registered the study with the German Center for Infection Research (https://dzif.clinicalsite.org/de/cat/2099/trial/4361).

Stem cell donor registry activities during the COVID-19 pandemic: a field report by DKMS.

The COVID-19 pandemic has serious implications also for patients with other diseases. Here, we describe the effects of the pandemic on unrelated hematopoietic stem cell donation and transplantation from the perspective of DKMS, a large international donor registry. Especially, we cover the development of PBSC and bone marrow collection figures, donor management including Health and Availability Check (HAC), transport and cryopreservation of stem cell products, donor recruitment and business continuity measures. The total number of stem cell products provided declined by around 15% during the crisis with a particularly strong decrease in bone marrow products. We modified donor management processes to ensure donor and product safety. HAC instead of confirmatory typing was helpful especially in countries with strict lockdowns. New transport modes were developed so that stem cell products could be safely delivered despite COVID-19-related travel restrictions. Cryopreservation of stem cell products became the new temporary standard during the pandemic to minimize risks related to transport logistics and donor availability. However, many products from unrelated donors will never be transfused. DKMS discontinued public offline donor recruitment, leading to a 40% decline in new donors during the crisis. Most DKMS employees worked from home to ensure business continuity during the crisis.