Increased cell surface expression of histocompatibility class II I-A(d) in c-fos transfected clones of the P388D1 murine macrophage cell line.

Numerous biological functions of the monocyte-macrophage lineage are affected by the presence of immunomodulators. Enhancement in transcription of c-fos has been shown in the murine P388D1 macrophage line treated by LPS, TPA, Ca++ ionophore or dibutyryl cAMP. In order to study the effects of an increased c-Fos protein level on macrophage functions, we previously have established stable c-fos-overexpressing clones in the P388D1 cell line.

CREB is involved in mouse annexin A1 regulation by cAMP and glucocorticoids.

A cAMP and some glucocorticoid response elements have been underlined in the promoter of mouse annexin A1. To analyse the function of these DNA sequences, the role of cAMP and glucocorticoids, as well as the transcription factors involved in their activation, were investigated. A construct containing 1381 bp of the DNA 5'-flanking annexin A1 gene fused to LacZ was used.

Effect of c-Fos overexpression on the murine macrophage cell line P388DI.

In order to study the role of Fos on the regulation of proliferation in the monocyte-macrophage lineage we realized a stable transfection of the murine P388D1 cell line by the murine c-fos gene under the control of the human metallothionein IIA promoter. Several clones have been selected by geneticin: they show a variable number of integrated transgene (two to ten copies). Their expression has been analyzed in the presence or absence of cadmium chloride as inducer (5 x 10(-6) M).

Expression of c-fos and c-myc oncogenes in the P388D1 murine macrophage line treated by immunomodulators: absence of direct correlation with DNA synthesis.

Complex patterns of metabolic and functional characteristics are induced in macrophages by biological response modifiers. The study of the early events resulting from the transduction of immunomodulatory signals could be an approach for a better understanding of this activation process. The transcription of c-fos and c-myc genes has been shown to be rapidly modified in many cells responding to various signals.

C-fos and c-myc modulation, mitogenic effect and Ia expression in the P388D1 murine macrophage line treated by immunomodifiers.

The aim of the present study was to investigate whether the early modulation of the c-fos and c-myc oncogenes could give some orientation to the impact of immunomodulators on the monocyte-macrophage lineage. In order to work in a homogeneous system we used the P388D1 mouse macrophage cell-line which is considered as an almost mature macrophage. When P388D1 cells were stimulated by LPS, interferon-gamma or the association of both compounds, no direct correlation could be found between the modulation of DNA synthesis and the early expression of the c-fos and c-myc oncogenes.