The use of plasma HIV RNA as a study endpoint in efficacy trials of antiretroviral drugs.

Objectives: To evaluate the utility of HIV RNA as an endpoint in antiretroviral efficacy studies.

Design: Data collected from antiretroviral efficacy trials were analyzed to explore relationships between clinical progression and the magnitude, nadir and duration of HIV RNA reductions. The proportion of patients suppressing HIV RNA below assay quantification, time to maximal virologic response, and loss of virologic response in relation to pretreatment characteristics were also analyzed.

Characterization of Langat virus antigenic determinants defined by monoclonal antibodies to E, NS1 and preM and identification of a protective, non-neutralizing preM-specific monoclonal antibody.

Hybridomas secreting monoclonal antibodies (MAb) to the tick-borne encephalitis (TBE) group virus, Langat virus (LGTV), were prepared. Of more than 200 MAb screened, 19 antibodies, which cross-reacted with the etiologic agent of Central European encephalitis, were selected for further characterization. Of these MAb, 15 were specific for LGTV E glycoprotein, two for the NS1 protein, and three for preM protein.

Enzyme-linked immunosorbent assay using a recombinant baculovirus-expressed Bacillus anthracis protective antigen (PA): measurement of human anti-PA antibodies.

We developed an antigen capture enzyme-linked immunosorbent assay (ELISA) which does not require purified protective antigen (PA) for detection of human antibodies to Bacillus anthracis PA. Lysates of Spodoptera frugiperda (Sf-9) cells infected with recombinant baculovirus containing the PA gene were used as the source of PA to develop the ELISA. Recombinant PA from crude Sf-9 cell lysates or PA purified from B.

The Langat model for tick-borne encephalitis virus. Specific detection by RT-PCR.

We have developed a reverse-transcriptase polymerase chain reaction assay for rapid detection of Langat (LGT) virus, a flavivirus that is closely related to the highly pathogenic tick-borne encephalitis (TBE) viruses. Unlike TBE viruses, LGT virus exhibits a significantly lower virulence for man. The assay serves as a safe alternative for the development and optimization of specific assays for the highly pathogenic subtypes of TBE viruses that are endemic throughout much of Europe, the former Soviet Union, and China.