Hantavirus Pulmonary Syndrome: CD8+and CD4+Cytotoxic T Lymphocytes to Epitopes on Sin Nombre Virus Nucleocapsid Protein Isolated during Acute Illness

AbstractIn 1993 a number of cases of unexplained adult respiratory syndrome occurred in the southwestern United States. The illness was characterized by a prodrome of fever, myalgia, and other symptoms followed by the rapid onset of a capillary leak syndrome with hemoconcentration, thrombocytopenia, and pulmonary edema. Viral RNA sequences in the lungs identified a new member of the hantavirus genus, Sin Nombre virus (SNV), unique to North America. Pulmonary endothelial cells were heavily infected but were not necrotic. We speculated that this capillary leak syndrome was initiated by immune responses to the SNV-infected pulmonary endothelial cells. We isolated a CD8+cytotoxic T lymphocyte (CTL) clone directly from the blood of a patient with the acute hantavirus pulmonary syndrome (HPS) which recognizes a SNV specific epitope on the virus nucleocapsid protein (aa 234–242) that is restricted by HLA C7 and produces IFNγ but not IL-4. We identified a second CD8+CTL epitope located within another site aa 131–139 on the nucleocapsid protein, which is HLA B35 restricted, and a CD4+CTL epitope located on a third site on nucleocapsid protein aa 372–380 using lymphocytes obtained during HPS from another patient that were stimulatedin vitro.Hantavirus specific CD8+and CD4+CTL may contribute to the immunopathology and capillary leak syndrome observed in the HPS

Genetic Characterization of Hantaviruses Transmitted by the Korean Field Mouse (Apodemus peninsulae), Far East Russia

In an epizootiologic survey of 122 rodents captured in Vladivostok, Russia, antibodies positive for hantavirus were found in Apodemus peninsulae (4/70), A. agrarius (1/39), and Clethrionomys rufocanus (1/8). The hantavirus sequences identified in two seropositive A. peninsulae and two patients with hemorrhagic fever with renal syndrome (HFRS) from the Primorye region of Far East Russia were designated as Solovey and Primorye, respectively. The nucleotide sequences of the Solovey, Primorye, and Amur (obtained through GenBank) sequences were closely related (>92% identity). Solovey and Primorye sequences shared 84% nucleotide identity with the prototype Hantaan 76-118. Phylogenetic analysis also indicated a close relationship between Solovey, Primorye, Amur, and other viruses identified in Russia, China, and Korea. Our findings suggest that the Korean field mouse (A. peninsulae) is the reservoir for a hantavirus that causes HFRS over a vast area of east Asia, including Far East Russia

Production of specific antibodies against SARS-coronavirus nucleocapsid protein without cross reactivity with human coronaviruses 229E and OC43

Severe acute respiratory syndrome (SARS) is a life-threatening disease for which accurate diagnosis is essential. Although many tools have been developed for the diagnosis of SARS, false-positive reactions in negative sera may occur because of cross-reactivity with other coronaviruses. We have raised polyclonal and monoclonal antibodies (Abs) using a recombinant form of the SARS virus nucleocapsid protein. Cross-reactivity of these anti-SARS Abs against human coronavirus (HCoV) 229E and HCoV OC43 were determined by Western blotting. The Abs produced reacted with recombinant SARS virus nucleocapsid protein, but not with HCoV 229E or HCoV OC43

Inactivation of SARS coronavirus by means of povidone-iodine, physical conditions, and chemical reagents

products, a number of other chemical agents, and various physical conditions were evaluated for their ability to inactivate the severe acute respiratory syndrome coronavirus (SARS-CoV). Treatment of SARS-CoV with PVP-I products for 2 min reduced the virus infectivity from 1.17 x 10⁶ TCID₅₀/ml to below the detectable level. The efficacy of 70% ethanol was equivalent to that of PVP-I products. Fixation of SARS-CoV-infected Vero E6 cells with a fixative including formalin, glutaraldehyde, methanol, and acetone for 5 min or longer eliminated all infectivity. Heating the virus at 56℃ for 5 min dramatically reduced the infectivity of the virus from 2.6 x 10⁷ to 40 TCID₅₀/ml, whereas heating the virus for 60 min or longer eliminated all infectivity. Irration with ultraviolet light at 134μQ/cm² for 15 min reduced the infectivity from 3.8 x 10⁷ to 180 TCID₅₀/ml; however, prolonged irradiation (60 min) failed to eliminate the remaining virus, leaving 18.8 TCID₅₀/ml. We beleave that these finding will be useful for the implementation of infection control measures against SARS, and for the establishment of effective guidlines for the preventation of SARS outbreaks