Idiotypes and biological activity of murine monoclonal antibodies against the hemagglutinin of measles virus

Three hybridomas, designated C2, V17, and B2, were produced from BALB/c mice after immunization with measles virus. All three were directed against the virus hemagglutinin (HA). The HA is a structural peptide of the virus and constitutes a major target for the host immune response during measles infection. The monoclonal anti-HA antibodies have biological functions such as (i) measles virus neutralization in vitro, (ii) binding to acutely and persistently infected cells, and (iii) inhibition of HA-mediated Rhesus monkey erythrocyte agglutination. Different idiotypes, designated HAMM-1, HAMM-2, and HAMM-3, were defined on C2, V17, and B2, respectively, by syngeneic anti-idiotype sera against those three monoclonal antibodies. A limited cross-reactivity with the HAMM-1 idiotype was detected in sera from some BALB/c mice immunized with measles virus. The anti-idiotype sera could significantly inhibit the biological functions of the HAMM-1 and HAMM-3 idiotypes bearing monoclonal anti-HA-antibodies. This suggests a possible role for auto-anti-idiotypes in the immune response after infection with measles virus

Lessons learned from 2 patients with multidrug-resistant HIV-1 infection successfully treated with a darunavir-containing antiretroviral treatment regimen

The authors describe 2 patients with life-threatening multidrug-resistant HIV-1 infection who responded very well to a treatment regimen containing darunavir and enfuvirtide. They discuss the availability of several new treatment options such as darunavir, etravirine, integrase, and CCR5 inhibitors for patients with multidrug-resistant viruses

Antibody-Mediated Modification of Encephalitis Induced by Hamster Neurotropic Measles Virus

The acute encephalopathy induced by hamster neurotropic (HNT) measles virus in BALB/c mice was abolished, and a subacute encephalitis was induced instead, when antibody to Edmonston (Ed) measles virus was administered three days after inoculation of HNT virus. Ascites fluid from 79XICl, a monocolonal antibody to the hemagglutinin of strain Ed, had similar effects in vivo. However, other monoclonal antibodies to the hemagglutinin of Ed strain-79XVV17 and 80IIIB2-were ineffective in vivo at all doses tested. By viral neutralization, immunofluorescence, and radioimmunoprecipitation assays, it was shown that the hemagglutinin of HNT virus reacted with 79XICl antibody but lacked the epitopes recognized by 79XVV17 or 80IIIB2 antibody, a finding that explains their different reactivity in vivo. These observations also identified previously unrecognized antigenic differences between the hemagglutinin of Ed and HNT measles viruses