ABSTRACT
The SARS-CoV-2 outbreak is causing widespread infections and significant mortality. Previous studies describing clinical characteristics of the disease contained small cohorts from individual centers or larger series consisting of mixed cases from different hospitals. We report analyses of mortality and disease severity among 402 patients from a single hospital. The cohort included 297 patients with confirmed and 105 with suspected diagnosis. The latter group met the criteria for clinical diagnosis but nucleic acid tests results were initially interpreted as suspicious. Data were compared between genders and among different age groups. The overall case fatality is 5.2%. However, patients 70 years of age or older suffered a significantly higher mortality (17.8%), associated with more patients having severe or critical illness (57.5%). Patients 50 years of age or older had a mortality of 8.0%, and those younger than 50 years, 1.2%. Male patients had a mortality of 7.6% versus 2.9% in females.
ABSTRACT
<p><b>OBJECTIVE</b>To study the passive immunization with human monoclonal antibodies as for prophylaxis of human cytomegalovirus (HCMV) infection.</p><p><b>METHODS</b>Fab monoclonal antibodies to HCMV were recovered by repertoire cloning of mRNA from a HCMV infected individual. Antigen binding specificity, CDR sequence of V(H) and V(L) and neutralizing activity on HCMV AD169 stain were analyzed in vitro. The light and heavy chain Fd fragment genes of Fab antibodies were further cloned into a recombinant baculovirus expression vector pAC-kappa-Fc to express intact IgG. Secreted products were purified with affinity chromatography using protein G.</p><p><b>RESULTS</b>SDS-PAGE and Western blot confirmed the expression of the intact IgG. Immuno-blotting and -precipitation were used to identify HCMV proteins. One Fab monoclonal antibody recognized a conformational HCMV protein.</p><p><b>CONCLUSION</b>IgG antibodies can neutralize the HCMV AD169 strain efficiently at a titer of 2.5 microg/mL and may prove valuable for passive immunoprophylaxis against HCMV infection in humans.</p>
Subject(s)
Animals , Humans , Amino Acid Sequence , Base Sequence , Cell Line , Cloning, Molecular , Cytomegalovirus , Allergy and Immunology , DNA, Viral , Genetics , Genes, Viral , Immunoblotting , Immunoglobulin G , Allergy and Immunology , Immunoprecipitation , Insecta , Molecular Sequence Data , Peptide Library , Recombinant Proteins , Allergy and ImmunologyABSTRACT
The G1 cytoplasmic tail of Hantaan virus (HTNV) harbors a highly conserved region, which is homologous to immunoreceptor tyrosine-based activation motifs (ITAM) and is termed the ITAM-like sequence. To demonstrate the potential signal-transducing activity of G1 ITAM-like sequence resembling the canonical ITAM within immune and endothelial cells, a series of experiments were performed to define its interaction with cellular kinases. The synthesized G1 ITAM-like peptide was shown to coprecipitate with cellular phosphoprotein complexes by an immune-complex kinase assay. Mutational analyses showed that this ITAM-like sequence was a substrate for the Src family kinase Fyn, and two conserved tyrosine residues were required for coprecipitating Lyn, Syk, and ZAP-70 kinases. These findings demonstrated that HTNV envelope glycoprotein G1 contains a functional ITAM-like sequence in its cytoplasmic tail, which can bind critical cellular kinases that regulate immune and endothelial cell functions.