Interferon Production in Murine Macrophage-Like Cell Lines

Abstract
Five murine macrophage (MΦ)-like cell lines were examined to determine their suitability for the characterization of MΦ interferons (IFNs). The J774A.1, RAW 309 Cr.1, and RAW 264.7 cell lines produced 30–800 international units (IU)/ 106 cells when treated with 5–200 μg of bacterial lipopolysaccharide (LPS). No IFN was detected in LPS-treated P388D1 or PU5-1.8 cell cultures. All cell lines produced IFN when inoculated with Newcastle disease virus (NDV); however, only 15 IU/106 cells of acid stable IFN were produced in PU5-1.8 cell cultures in comparison to 4.2 × 103-1.7 × 104 IU/106 cells in the other cell lines. Most of the IFN was produced within 4 h in LPS-treated cell cultures and within 12 h in NDV-infected cell cultures. All IFNs were stable at pH 2.0 and were neutralized with antiserum against mouse L cell IFN. These cell lines appear competent for use in studying the synthesis, molecular weights, and regulatory functions of MΦ IFNs.