Four neonates had solitary, congenital, rapidly growing, spontaneously ulcerating tumors of the face, trunk, and extremities. No extracutaneous involvement was found, and all lesions spontaneously involuted. Mononuclear cells of the cutaneous infiltrate were Langerhans' cells. These findings expand the spectrum of congenital self-healing reticulohistiocytosis. The Langerhans' cells (LC), dendri...

Microglial response factor-1 is a newly isolated microglial gene, which encodes a Ca(2+) binding protein MRF-1 expressed in microglia and macrophages. We induced 1 h of focal cerebral ischemia or 10 min of global cerebral ischemia in the rat, and investigated the expression of MRF-1 immunoreactivity following ischemia. MRF-1 was present in resting microglia and was upregulated in response to mi...

Macrophages are terminally differentiated cells of the mononuclear phagocyte system that also encompasses dendritic cells, circulating blood monocytes, and committed myeloid progenitor cells in the bone marrow. Both macrophages and their monocytic precursors can change their functional state in response to microenvironmental cues exhibiting a marked heterogeneity. However, there are still uncer...

INTRODUCTION Hemophagocytic syndrome is a rare clinicopathological condition characterized by the activation of the mononuclear phagocyte system, resulting in hemophagocytosis in the reticuloendothelial systems. The pathogenesis of HPS remains unclear. CASE PRESENTATION We report the case of a 20-year-old soldier suffering from HPS. Because of long history fever and no reasons being found, hi...

A patient presented initially with a testicular mass, which on biopsy had morphological features consistent with malignant histiocytosis. The tumour cells labelled strongly with EBM/11, a murine monoclonal antibody with high specificity for cells of the human mononuclear phagocyte system. Subsequent clinical and laboratory studies confirmed the diagnosis. As poorly differentiated tumour cells r...

Human immunodeficiency virus type 1 (HIV-1) infection in mononuclear phagocyte lineage cells (monocytes, macrophages, and microglia) is a critical component in the pathogenesis of viral infection. Viral replication in macrophages serves as a reservoir, a site of dissemination, and an instigator for neurological sequelae during HIV-1 disease. Recent studies demonstrated that chemokine receptors ...

Recent work in our laboratory with mouse radiation chimeras suggests that the macrophage type of synovial lining cell is derived from bone marrow. Further evidence for including this cell type in he mononuclear phagocyte system is now presented. Rosette formation with IgG coated sheep red cells, immunofluorescent staining for surface Ia antigens, and nonspecific esterase staining all show the p...

A nano-hydroxyapatite/collagen composite was prepared by precipitation of hydroxyapatite from an aqueous solution onto collagen. Mouse peritoneal macrophages were used to investigate the in vitro biodegradation of the composite. The results showed the mechanism of phagocytosis and extracellular degradation process. The cells that belong to the mononuclear phagocyte system showed some morphologi...

Malakoplakia, first described by Michaelis and Gutmann in 1902 [1], occurs mainly in the genitourinary tract (60% of cases), and less frequently in the gastrointestinal tract (10% of cases) [2]. Although the pathogenesis of malakoplakia is not completely understood, the disease may be considered the result of an impairment of the mononuclear phagocyte and immunoregulatory effector system [3]. T...