Suspected chromosomally integrated human herpes virus 6 in hematopoietic stem cell transplantation

Background and aims: We report a case of a 27-year-old male affected by acute myeloid leukaemia MLL-PTD positive. After autologous stem cell transplantation, he was monitored based on cytomegalovirus, Epstein-Barr virus and human herpes virus 6 (HHV-6) DNA quantification in blood. Relapse occurred one year after transplantation; then the patient underwent to allogenic bone marrow transplantation using genotypically HLA-identical donor (sister). HHV-6 DNAemia was positive and persistently elevated, either after autologous either after allogenic transplant suggesting the occurrence of HHV-6 chromosomally integration. The work aim is to prove the occurrence of chromosomally integrated-HHV-6 (ci-HHV-6). Materials and Methods: HHV-6 DNA extraction was performed by automated extractor and DNA was amplified-quantified by Real Time polymerase chain reaction. Species identification was performed by sequencing HHV6-U100 glycoprotein using automated sequencer and sequencing products were analysed using the Blast program. Results: After autologous transplantation HHV6-DNAemia was 5.4 log copies/mL setting to 3.9 log copies/mL for a long period post allogenic transplantation. The patient’s hair follicles were tested for HHV- 6 DNA having positive results. Sequences of both strains of HHV6 extracts from blood and hair follicles resulted species B. HHV6 viral load decreased significantly after Lymphocyte Infusion by ci-HHV6 negative donor (sister), having steady viral load during the following six months of monitoring. One year later, patient is in complete haematological remission. Conclusions: Detection of HHV-6 in hair follicles and HHV-6 DNAemia persistently elevated before allogenic transplant, confirm the occurrence of ci-HHV-6. The observed important decreasing viral load is potentially due to the successful engraftment of ci-HHV-6-negative donor marrow after allogeneic transplant

Oxalomalate affects the inducible nitric oxide synthase expression and activity

Inducible nitric oxide synthase (iNOS) is an homodimeric enzyme which produces large amounts of nitric oxide (NO) in response to inflammatory stimuli. Several factors affect the synthesis and catalytic activity of NOS. Particularly, dimerization of NOS monomers is promoted by heme, whereas an intracellular depletion of heme and/or L-arginine considerably decreases NOS resistance to proteolysis. In this study, we found that oxalomalate (OMA, oxalomalic acid, alpha-hydroxy-beta-oxalosuccinic acid), an inhibitor of both aconitase and NADP-dependent isocitrate dehydrogenase, inhibited nitrite production and NOS protein expression in lipopolysaccharide (LPS)-activated J774 macrophages, without affecting NOS mRNA content. Furthermore, injection of OMA precursors to LPS-stimulated rats also decreased nitrite production and NOS expression in isolated peritoneal macrophages. Interestingly, alpha-ketoglutarate or succinyl-CoA administration reversed OMA effect on NO production, thus correlating NO biosynthesis with the anabolic capacity of Krebs cycle. When protein synthesis was blocked by cycloheximide in LPS-activated J774 cells treated with OMA, NOS protein levels, evaluated by Western blot analysis and 35 S-metabolic labelling, were decreased, suggesting that OMA reduces NOS biosynthesis and induces an increase in the degradation rate of NOS protein. Moreover, we showed that OMA inhibits the activity of the NOS from lung of LPS-treated rats by enzymatic assay. Our results, demonstrating that OMA acts regulating synthesis, catalytic activity and degradation of NOS, suggest that this compound might have a potential role in reducing the NO overproduction occurring in some pathological conditions. (c) 2007 Elsevier Inc. All rights reserved

Loss of Detection of sgN Precedes Viral Abridged Replication in COVID-19-Affected Patients—A Target for SARS-CoV-2 Propagation

The development of prophylactic agents against the SARS-CoV-2 virus is a public health priority in the search for new surrogate markers of active virus replication. Early detection markers are needed to follow disease progression and foresee patient negativization. Subgenomic RNA transcripts (with a focus on sgN) were evaluated in oro/nasopharyngeal swabs from COVID-19-affected patients with an analysis of 315 positive samples using qPCR technology. Cut-off Cq values for sgN (Cq O-methyl antisense RNA (related to the sgN sequence) can impair SARS-CoV-2 N protein synthesis, viral replication, and syncytia formation in human cells (i.e., HEK-293T cells overexpressing ACE2) upon infection with VOC Alpha (B.1.1.7)-SARS-CoV-2 variant, defining the use that this procedure might have for future therapeutic actions against SARS-CoV-2