In vivo dendritic cell depletion reduces breeding efficiency, affecting implantation and early placental development in mice.

Implantation of mammalian embryos into their mother's uterus ensures optimal nourishment and protection throughout development. Complex molecular interactions characterize the implantation process, and an optimal synchronization of the components of this embryo-maternal dialogue is crucial for a successful reproductive outcome. In the present study, we investigated the role of dendritic cells (DC) during implantation process using a transgenic mouse system (DTRtg) that allows transient depletion of CD11c+ cells in vivo through administration of diphtheria toxin.

A Role of Endogenous Retroviral MCF env Gene in Proliferation of Pluripotent Hemopoietic Progenitors in Mice.

We have investigated the role of endogenous retroviral mink cell focus-forming (MCF) genes in the regulation of mouse bone marrow hemopoietic progenitor cell proliferation. The p15E protein coded by the MCF env gene is expressed by early hemopoietic progenitors, mostly on spleen colony forming units (CFUs-12) and on erythropoietin-independent erythroid progenitors. Stimulation of cell proliferation in hemopoietic precursors by steroid hormone (testosterone propionate) treatment resulted in upregulation of the expression of the endogenous p15E protein on bone marrow cells.

Production of Peptide of Retroviral Origin in Sera of Patients with Chronic Myeloid Leukemia at Acute Phase.

In the present study we investigated production of the peptide of retroviral origin in patients with various types of leukemia. For this purpose the high affinity rabbit antibodies were generated against the synthetic peptide representing the "immunosuppressive motif" within the envelope protein of human endogenous retrovirus type C. The presence of this peptide was identified only in sera of the patients with chronic myelo- and/or promonocytic leukemia at acute phase.