SARS-CoV-2 in an immunocompromised host: convalescent plasma therapy and viral evolution elucidated by whole genome sequencing

The evolution of SARS-CoV-2 within immunocompromised hosts who fail to clear the virus over many months has been proposed as a route to the development of Variants of Concern (VoCs). We present a case of an immunocompromised male patient with a prolonged SARS-CoV-2 infection. During hospitalisation, 7 weeks after first diagnosis, his condition worsened to require continuous ventilation support. Resolution of symptoms was observed after convalescent plasma therapy. Whole genome sequencing of the virus showed Pango lineage B.1.221. Between the first sample and the second from bronchoalveolar lavage fluid 7 weeks later, we identified eight mutations, including minor variants, which could be used to estimate the chronology of mutations. This suggests an elevated mutation rate, in-host accumulation of mutations and further evidence for sources of VoCs. Prolonged SARS-CoV-2 infections in immunocompromised hosts increase the likelihood of hospital stays and morbidity, and also pose an increased risk to global public health

Clinical Study The Use of Interferon Gamma Release Assays in the Diagnosis of Active Tuberculosis

Interferon gamma release assays (IGRAs) are in vitro immunologic diagnostic tests used to identify Mycobacterium tuberculosis infection. They cannot differentiate between latent and active infections. The cutoff suggested by the manufacturer is 0.35 IU/mL for latent tuberculosis. As IGRA tests were recently approved for the differential diagnosis of active tuberculosis, we assessed the diagnostic accuracy of the latest generation IGRA for detection of active tuberculosis in a low-incidence area in Germany. Our consecutive case series includes 61 HIV negative, Mycobacterium tuberculosis culture positive patients, as well as 234 control patients. The retrospective analysis was performed over a period of two years. In 11/61 patients with active tuberculosis (18.0%) the test result was <0.35 IU/mL, resulting in a sensitivity of 0.82. We recommend establishing a new cut-off value for the differential diagnosis of active tuberculosis assessed by prospective clinical studies and in various regions with high and low prevalence of tuberculosis

Detection of Viral Infection and Bacterial Coinfection and Superinfection in Coronavirus Disease 2019 Patients Presenting to the Emergency Department Using the 29-mRNA Host Response Classifier IMX-BVN-3: A Multicenter Study.

Background Identification of bacterial coinfection in patients with coronavirus disease 2019 (COVID-19) facilitates appropriate initiation or withholding of antibiotics. The Inflammatix Bacterial Viral Noninfected (IMX-BVN) classifier determines the likelihood of bacterial and viral infections. In a multicenter study, we investigated whether IMX-BVN version 3 (IMX-BVN-3) identifies patients with COVID-19 and bacterial coinfections or superinfections. Methods Patients with polymerase chain reaction-confirmed COVID-19 were enrolled in Berlin, Germany; Basel, Switzerland; and Cleveland, Ohio upon emergency department or hospital admission. PAXgene Blood RNA was extracted and 29 host mRNAs were quantified. IMX-BVN-3 categorized patients into very unlikely, unlikely, possible, and very likely bacterial and viral interpretation bands. IMX-BVN-3 results were compared with clinically adjudicated infection status. Results IMX-BVN-3 categorized 102 of 111 (91.9%) COVID-19 patients into very likely or possible, 7 (6.3%) into unlikely, and 2 (1.8%) into very unlikely viral bands. Approximately 94% of patients had IMX-BVN-3 unlikely or very unlikely bacterial results. Among 7 (6.3%) patients with possible (n = 4) or very likely (n = 3) bacterial results, 6 (85.7%) had clinically adjudicated bacterial coinfection or superinfection. Overall, 19 of 111 subjects for whom adjudication was performed had a bacterial infection; 7 of these showed a very likely or likely bacterial result in IMX-BVN-3. Conclusions IMX-BVN-3 identified COVID-19 patients as virally infected and identified bacterial coinfections and superinfections. Future studies will determine whether a point-of-care version of the classifier may improve the management of COVID-19 patients, including appropriate antibiotic use

Thymulin gene therapy prevents the reduction in circulating gonadotropins induced by thymulin deficiency in mice

Integrity of the thymus during perinatal life is necessary for a proper maturation of the pituitarygonadal axis in mice and other mammalian species. Thus congenitally athymic (nude) female mice show significantly reduced levels of circulating gonadotropins, a fact that seems to be causally related to a number of reproductive derangements described in these mutants. Interestingly, a number of in vitro studies suggest that the thymic peptide thymulin may be involved in thymus-pituitary communication. To determine the consequences of low serum thymulin in otherwise normal animals, we induced short (8 days)- and long (33 days)-term thymulin deficiency in C57BL/6 mice by neonatally injecting (intraperitoneally) an anti-thymulin serum and assessed their circulating gonadotropin levels at puberty and thereafter. Control mice received an irrelevant antiserum. Gonadotropins were measured by radioimmunoassay and thymulin by bioassay. Both long- and short-term serum thymulin immunoneutralization resulted in a significant reduction in the serum levels of gonadotropins at 33 and 45 days of age. Subsequently, we injected (intramuscularly) an adenoviral vector harboring a synthetic DNA sequence (5′- ATGCAAGCCAAATCTCAAGGTGGATCCAACTAGTAG-3′) encoding a biologically active analog of thymulin, methionine-FTS, in newborn nude mice (which are thymulin deficient) and measured circulating gonadotropin levels when the animals reached 52 days of age. It was observed that neonatal thymulin gene therapy in the athymic mice restored their serum thymulin levels and prevented the reduction in circulating gonadotropin levels that typically emerges in these mutants after puberty. Our results indicate that thymulin plays a relevant physiological role in the thymuspituitary-gonadal axis.Instituto de Investigaciones Bioquímicas de La Plat

Studien in Mäusen über die Rolle des thymischen Hormones Thymulin in der Neonatalperiode als Reifungsfaktor für das neuroendokrine System

Cover and Table of Contents Introduction Hypothesis and Research Objectives Animals, Materials and Methods Experimental Results Discussion Future Directions ReferencesThe thymic peptide thymulin was discovered, purified and sequenced in the 70s. In a series of early studies, thymulin was thoroughly characterized in relation to its immunological actions. It was shown to be involved in several aspects of intra- and extrathymic T-cell differentiation. Further studies revealed that thymulin secretion was affected by a complex endocrine network involving most adenohypophyseal and peripheral hormones, and that thymulin itself strongly influences the neuroendocrine system. In the present doctoral thesis anti-thymulin specific antibodies were generated in rabbits and chickens. An ELISA for thymulin was set up using mammalian antibodies. Rabbit antisera were specific for thymulin but chicken antibodies were found to produce strong nonspecific interactions when used in ELISA. Long- (33 days) and short- (7 days) term neonatal immunoneutralization studies on mice employing the anti-thymulin antibodies raised in rabbits revealed a strong reduction in the serum levels of most anterior pituitary hormones (LH, FSH, PRL, TSH and GH) when the treated animals reached an adult age. Pituitary cell populations were also affected by the treatment. Additionally, body weight decreased and thymic cellularity increased in the thymulin-deprived animals. We conclude that thymulin has a general facilitatory action on anterior pituitary hormone secretion and that this thymic peptide plays a key role during early life for the development of a proper neuroendocrine balance in adult animals.Das thymische Peptid Thymulin wurde in den 70er Jahren entdeckt, purifiziert und sequenziert. In einer Reihe von Studien wurde Thymulin eingehend hinsichtlich seiner immunologischen Funktionen charakterisiert. Es wurde gezeigt, dass es an zahlreichen Aspekten intra- und extrathymischer T-Zell- Differenzierung beteiligt ist. Weitere Studien ergaben, dass die Sekretion von Thymulin durch ein komplexes Netzwerk gesteuert wird, an dem adenohypophysäre und periphere Hormone beteiligt sind, und dass Thymulin seinerseits sehr starken Einfluss auf das neuroendokrine System hat. In der vorliegenden Doktorarbeit wurden anti-Thymulin-spezifische Antikörper in Kaninchen und Hühnern generiert. Ein ELISA für Thymulin wurde auf der Basis polyklonaler Kaninchenantikörper entwickelt. Kaninchenseren stellten sich als spezifisch für Thymulin heraus, wohingegen Hühnerantikörper starke unspezifische Interaktionen im ELISA zeigten. Neonatale Langzeit- (33 Tage) und Kurzzeit- (7 Tage) Immunoneutralisierungs-Studien in Mäusen führten nach Erreichen des Erwachsenenalters zu stark reduzierten Serumspiegeln adenohypophysärer Hormone (LH, FSH, PRL, TSH, GH). Die Morphologie hypophysärer Zellen zeigte in diesem Experiment ebenfalls Veränderungen. Außerdem waren in den Thymulin-defizienten Tieren das Körpergewicht erniedrigt und der Zellgehalt des Thymus erhöht. Es kann gefolgert werden, dass Thymulin eine generelle sekretionsfördernde Wirkung auf die Adenohypophyse hat und dass dieses Peptid in der Neonatalperiode eine Schlüsselrolle für die normale Entwicklung des späteren neuroendokrinen Gleichgewichtes hat

SARS-CoV-2 in an immunocompromised host: convalescent plasma therapy and viral evolution elucidated by whole genome sequencing.

The evolution of SARS-CoV-2 within immunocompromised hosts who fail to clear the virus over many months has been proposed as a route to the development of Variants of Concern (VoCs). We present a case of an immunocompromised male patient with a prolonged SARS-CoV-2 infection. During hospitalisation, 7 weeks after first diagnosis, his condition worsened to require continuous ventilation support. Resolution of symptoms was observed after convalescent plasma therapy. Whole genome sequencing of the virus showed Pango lineage B.1.221. Between the first sample and the second from bronchoalveolar lavage fluid 7 weeks later, we identified eight mutations, including minor variants, which could be used to estimate the chronology of mutations. This suggests an elevated mutation rate, in-host accumulation of mutations and further evidence for sources of VoCs. Prolonged SARS-CoV-2 infections in immunocompromised hosts increase the likelihood of hospital stays and morbidity, and also pose an increased risk to global public health

Elimination of cholera transmission

No abstract availabl

Minimal inhibitory concentrations of first-line drugs of multidrug -resistant tuberculosis isolates

Context: The treatment of multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis (TB) is consistently difficult. Besides resistances, drug availability can be problematic and costs for therapy are high. Aims: Our aim was to evaluate alternatives in treatment of MDR and XDR TB other than using second-line drugs. Materials and Methods: We analyzed retrospectively the minimal inhibitory concentrations (MICs) of first-line drugs for 44 multidrug-resistant Mycobacterium tuberculosis isolates determined in our institute over a period of 20 years (1990 - 2010, n = 44). Drug susceptibility testing (DST) was performed using the proportion method on Lowenstein-Jensen Medium or Middlebrook 7H10 agar. MICs were defined as the lowest drug concentration after two-fold serially diluted concentration of the drugs that inhibits growth of more than 99.0% of a bacterial proportion of the tested M. tuberculosis within 14 to 21 days of incubation at 37΀C. Statistical Analysis Used: Summation. Results: The MICs of isoniazid and ethambutol were equal or slightly above the critical concentration in most of the strains (92% and 84%, respectively), defined as "low-level resistance". Rifampicin and streptomycin exhibited very high MICs in most of the strains (100% and 77%, respectively), indicating a "high-level resistance". Conclusion: Our results indicate that isoniazid and ethambutol could still play a role in treating MDR and XDR TB patients if low-level resistance is detected. Quantitative DST seems to be promising for the recognition of residual drug activity, but has to be confirmed by clinical studies

The Use of Interferon Gamma Release Assays in the Diagnosis of Active Tuberculosis

Interferon gamma release assays (IGRAs) are in vitro immunologic diagnostic tests used to identify Mycobacterium tuberculosis infection. They cannot differentiate between latent and active infections. The cutoff suggested by the manufacturer is 0.35 IU/mL for latent tuberculosis. As IGRA tests were recently approved for the differential diagnosis of active tuberculosis, we assessed the diagnostic accuracy of the latest generation IGRA for detection of active tuberculosis in a low-incidence area in Germany. Our consecutive case series includes 61 HIV negative, Mycobacterium tuberculosis culture positive patients, as well as 234 control patients. The retrospective analysis was performed over a period of two years. In 11/61 patients with active tuberculosis (18.0%) the test result was <0.35 IU/mL, resulting in a sensitivity of 0.82. We recommend establishing a new cut-off value for the differential diagnosis of active tuberculosis assessed by prospective clinical studies and in various regions with high and low prevalence of tuberculosis