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BackgroundAdoptive therapy with SARS-CoV-2 specific T cells for COVID-19 has not been reported. The feasibility of rapid clinical-grade manufacturing of virus-specific T cells from convalescent donors has not been demonstrated for this or prior pandemics. MethodsOne unit of whole blood was collected from each convalescent donor following standard blood bank practices. After the plasma was separated and stored separately, the leukocytes were stimulated using overlapping peptides of SARS-CoV-2, covering the immunodominant sequence domains of the S protein and the complete sequence of the N and M proteins. Thereaftesr, functionally reactive cells were enriched overnight using an automated device capturing IFN{gamma}-secreting cells. FindingsFrom 1x109 leukocytes, 0.56 to 1.16x106 IFN{gamma}+ T cells were produced from each of the first two donors. Most of the T cells (64% to 71%) were IFN{gamma}+, with preferential enrichment of CD56+ T cells, effector memory T cells, and effector memory RA+ T cells. TCRV{beta} spectratyping revealed oligoclonal distribution, with over-representation of subfamilies including V{beta}3, V{beta}16 and V{beta}17. With just two donors, the probability that a recipient in the same ethnic group would share at least one donor HLA allele or one haplotype could be as high as >90% and >30%, respectively. InterpretationsThis study is limited by small number of donors and absence of recipient data; however, crucial first proof-of-principle data are provided demonstrating the feasibility of clinical-grade production of SARS-CoV-2 specific T cells for urgent clinical use, conceivably with plasma therapy concurrently. Our data showing that virus-specific T cells can be detected easily after brief stimulation with SARS-CoV-2 specific peptides suggest that a parallel diagnostic assay can be developed alongside serology testing. FundingThe study was funded by a SingHealth Duke-NUS Academic Medicine COVID-19 Rapid Response Research Grant.
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<p><b>INTRODUCTION</b>Febrile neutropenia (FN) remains a major cause of morbidity and mortality in Oncology/Haematology units. We launched a new protocol for FN management that incorporates risk stratification at our institute from October 2008. An audit was performed concurrently to evaluate the protocol and to define the epidemiology of FN locally.</p><p><b>MATERIALS AND METHODS</b>Case records of all inpatients with FN between October 2008 and June 2009 were reviewed prospectively. Clinical and microbiological characteristics were collated along with outcomes and programme adherence. Statistical testing was performed using Stata 10.1.</p><p><b>RESULTS</b>There were 178 FN episodes (50 in patients with solid cancers) from 131 patients. Forty-two (23.6%) episodes were classified as high-risk according to MASCC criteria. Initial blood cultures were positive in 49 (27.5%) episodes, of which gram-negative bacilli (GNB) predominated. Overall compliance to the protocol was 56.7%, with the main issue being disinclination to use oral antibiotics as fi rst-line empirical therapy for low-risk episodes. Overall mortality was 7.3% and infection-related mortality was 4.5%. High-risk FN and the presence of central venous catheters were independently associated with bacteraemia on multivariate analysis, but there were no independent predictors of infection-related mortality.</p><p><b>CONCLUSIONS</b>GNB accounted for the majority of bloodstream infections at our institute, unlike data from developed countries. Uptake of the new FN protocol was satisfactory, although the use of oral antibiotics as fi rst-line empirical therapy can be improved. A better method for predicting infections caused by antibiotic-resistant GNB is urgently required, and antibiotic resistance trends should be monitored to enable the implementation of more appropriate antibiotic regimens over time.</p>
