Patrick H. Cleveland

The role of interferons in the control of HIV replication in macrophages

Interferons can suppress the replication of certain retroviruses, including oncogenic murine retroviruses. In recent studies of the Lentivirinae subfamily of Retroviridae, an endogenous, immunologically induced interferon was found to restrict the replication of visna in macrophages. Several studies have shown that the replication of a human lentivirus, the human immunodeficiency virus (HIV), is also susceptible to interferon control. Here we review the evidence that interferons can protect macrophages from HIV in vitro. Macrophages treated with interferons or bacterial lipopolysaccharide (LPS) become essentially nonpermissive for HIV replication. Using the polymerase chain reaction to amplify HIV proviral DNA, we now report that interferon and LPS act to restrict the formation of proviral DNA. Effects on any several steps in the HIV life cycle may explain this data, and single-cycle infection studies are needed to define the precise roles of these agents. Taken together, these findings may explain the restricted replication of HIV in macrophages in vivo and suggest an antiviral role for endogenously produced interferon in the maintenance of the prolonged asymptomatic period which typically follows HIV infection. Interferons are currently undergoing clinical trials to determine if they have antiviral effects in HIV-infected patients.

Immobilization of viral antigens on filter paper for a [125I]staphylococcal protein a immunoassay: A rapid and sensitive technique for detection of herpes simplex virus antigens and antiviral antibodies

A new technique is described for the rapid detection and quantitation of herpes simplex virus (HSV) antigens and antiviral antibodies. It involves immobilization of HSV antigens on filter paper discs and subsequent analysis by 125I-labeled staphylococcal protein A (SPA) radioimmunoassay. A specially designed 96-well filtration device is employed which serves both as an incubation chamber and as a filtration manifold. It is rapid, simple, sensitive and specific, and requires only small volumes of antiserum and few target cells. The results may be readily and objectively quantitated. This technique permits the simultaneous assay of a large number of specimens in less than 1 h. Its sensitivity is considerably greater than that of other currently used immunologic techniques, and it is amenable to automation. These characteristics suggest that this [125I]SPA immunofiltration technique may be applicable to the rapid diagnosis of viral infections.

An enzyme immunofiltration assay useful for detecting human monoclonal antibody

A microenzyme-linked immunoassay (EIA) utilizing an immunofiltration manifold has been developed which provides a rapid, simple, and sensitive method of detecting human monoclonal antibody class, concentration, and specificity. In this assay either whole cells or soluble antigens were immobilized on glass fiber filters followed by incubating with the test human hybridoma supernatant with subsequent analysis by EIA. A specially designed 96-chamber immunofiltration plate is employed which serves as both an incubation chamber and as a filtration manifold. The assay described is unique in that small volumes of human hybridoma supernatant are required, crude preparation of only a few target cells are needed, labile cell surface antigens are preserved and it can be completed in 3 h. This assay is well suited for the rapid screening of large numbers of human hybridoma supernatants.

Immunoenzymatic staining of viral and chlamydial antigens in cell culture

Methods are described for the conjugation of antibodies with biotin and for the use of these reagents in an immunoperoxidase staining procedure for infected cell cultures. This technique provides a simple, rapid, and specific approach to the identification and characterization of a number of viral and chlamydial isolates in the diagnostic laboratory.