Aminated β-1,3-D-glucan has a dose-dependent effect on wound healing in diabetic db/db mice.

Inflammatory responses are common in diabetes and are operative in angiopathy, neuropathy, and wound healing. There are indications of incomplete macrophage activation in diabetes and reduced expression of growth factors. We have previously found that up to 15 topical applications of the macrophage-stimulant, aminated β-1,3-D-glucan (AG), improved wound healing in db/db mice.

Spontaneously formed tumorigenic hybrids of Meth A sarcoma cells and macrophages in vivo.

We have recently demonstrated that malignant cells can hybridize with tissue macrophages in vitro, giving rise to tumorigenic hybrids. We now demonstrate that this can occur spontaneously in vivo as a result of fusion between inoculated Meth A sarcoma cells and host cells, presumably macrophages. Thus, from tumor cell suspensions prepared by collagenase perfusion and density centrifugation, hybrid cells could be isolated that were neoplastic but in contrast to Meth A expressed macrophage markers and had phagocytic capacity.

From inflammation to sickness: historical perspective.

The concept of the four cardinal signs of acute inflammation comes from antiquity as rubor et tumor cum calore et dolore, (redness and swelling with heat and pain) extended later by functio laesa (loss of function). The contemporary understanding of this process we owe to 19th-century milestone discoveries by Rudolph Virchow, Julius Cohnheim and Elie Metchnikoff. In the 20th century, the development of potent technological tools allowed the rapid expansion of knowledge of the cells and mediators of inflammatory processes, as well as the molecular mechanisms of their interactions.

Stress and immunity: minireview.

Stress, a state of threatened homeostasis, may be induced by various physical or psychological factors (stressors), including antigenic stimulation. Stressful experiences may affect both physical/psychological well being and immune functioning of humans and animals; the ongoing immune reaction may affect other physiological functions and psychological comfort. The molecular basis of these effects involves a network of multidirectional signalling and feedback regulations of neuroendocrine- and immunocyte-derived mediators.

[Mobilization of mesenchymal infection defense].

Background: Most infections are arrested in epithelial and superficial connective tissues long before antibodies and antigen specific killer cells have been induced; i.e. before the specific defence system has had time enough to come to the rescue.

Spontaneously formed tumorigenic hybrids of Meth A sarcoma and macrophages grow faster and are better vascularized than the parental tumor.

Macrophages and Meth A sarcoma cells spontaneously fuse and give rise to tumorigenic hybrid cell lines with a mixed phenotype. We report here that the hybrid tumors grow faster and have a strikingly better developed vasculature than the parent sarcoma. Thus, electron microscopy and immunohistochemical analysis revealed that in the most active areas of neovascularization, the tumors that emerged from inocula of monoclonal hybrid cell populations had a microvessel density nearly twice that of Meth A tumors after 1 week of growth.

Early vascular permeability in murine experimental peritonitis is co-mediated by resident peritoneal macrophages and mast cells: crucial involvement of macrophage-derived cysteinyl-leukotrienes.

The initial phase of zymosan-induced peritonitis involves an increase of vascular permeability (peak at 30 min) that is correlated with high levels of vasoactive eicosanoids, namely, prostaglandins (PGI2 and PGE2) of cyclooxygenase-1 origin (as estimated by RT-PCR) and cysteinyl-leukotrienes. Previously, we showed that the increase of vascular permeability can be attributed only partially to mast cells and their histamine, as seen in mast cell-deficient WBB6F1-W/Wv mice. Thus we aimed to identify the major cellular source(s) that mediate vasopermeability, as well as particular vasoactive mediators operating in this model.

Spontaneous hybridization of macrophages and Meth A sarcoma cells.

We present evidence of hybridization between Meth A sarcoma cells and syngeneic as well as semigeneic peritoneal macrophages. The resultant hybrids are characterized by morphology, membrane markers, ploidy, chromosomal content and functional features. Briefly, after a few days of coculture, cells appeared with morphology intermediate between the 2 original cell types.