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Gay and bisexual men continue to be the group most affected by HIV and AIDS in the UK. In 1996, as part of an effort to address this situation, a consortium of London health authorities commissioned a gay men's HIV prevention project based on principles of community mobilisation which the research literature suggests offers considerable scope for achieving effective HIV prevention. This impact evaluation study, analysing responses to a selfcompletion questionnaire administered to a community-based sample of 674 men in London, found highest reported levels of contact with the awarenessraising interventions in the project. Much lower levels of engagement with more participative and involving activities were identified. In relation to the reported outcomes of the project, awareness-raising was achieved to a greater extent than behavioural outcomes for prevention. Future gay men's HIV prevention based on community mobilisation should be oriented to focus more specifically on the achievement of these more complex outcomes. [ABSTRACT FROM AUTHOR]

Granulocyte colony-stimulating factor (G-CSF) was quantitated in the supernatants of lipopolysaccharide (LPS)-treated human monocytes by ELISA. Unlike previous reports, the lymphokines, interleukin-4 (IL-4) and interferon-γ (IFN-γ), were unable to induce the synthesis of G-CSF. Both IL-4 (⩾ 10 pM) and the glucocorticoid, dexamethasone (10-7 M), inhibited G-CSF production in the LPS-treated monocytes; in contrast, IFN-γ had a weak potentiating effect on the LPS action. Changes in antigen expression were manifested at the level of messenger RNA (mRNA). Granulocyte-macrophage (GM)-CSF in the LPS-treated monocyte supernatants was also quantitated by ELISA but its levels were somewhat lower than for G-CSF; IL-4, dexamethasone and IFN-γ had similar effects on GM-CSF levels as on G-CSF levels. The suppression of CSF production in the stimulated monocytes by IL-4 and glucocorticoid extends the list of monocyte cytokines whose levels can be down-regulated by these agents and suggests another potential anti-inflammatory and immunosuppressive function for IL-4. [ABSTRACT FROM AUTHOR]

There have been suggestions that the production of pro-inflammatory mediators by human monocytes in response to interferon-gamma (IFN-γ) may be controlled by changes in prostaglandins. Therefore we investigated tumour necrosis factor a (TNFα) and interleukin-1 (IL-1) activities and prostaglandin E2 (PGE2) levels in the supernatants of highly purified human monocytes cultured for 18 hr with recombinant human IFN-γ. IFN-γ (100 U/ml) did not stimulate monocytes isolated by counter-current centrifugal elutriation for detectable TNFα or IL-1 activities, or PGE2 production. However, IFN-γ synergistically enhanced lipopolysaccharide (LPS)-induced TNFα and IL-1 activities. In contrast, there was no consistent change in PGE2 levels upon addition of IFN-γ to LPS-treated monocyte cultures. The TNFα and IL-1 activities induced by LPS and by LPS with IFN-γ were reduced by PGE2, and stimulated by indomethacin. As reported previously for IL-1 activities, the regulation by cyclo-oxygenase products of TNFα activities reflected predominantly a control of the production of immunoreactive TNFα, rather than the measurement of TNFα bio-activity. However, the addition of indomethacin or PGE2 to monocyte cultures did not change the extent of IFN-γ synergy with LPS for increased TNFα and IL-1 activites. The results of this study suggest that, despite control by cyclo-oxygenase products of TNFα and IL-1 production in human monocytes, IFN-γ may enhance TNFα and IL-1 activities independently of this regulatory mechanism. These findings are contrary to those suggested for the regulation by prostanoids of IL-1 production by murine macrophages. [ABSTRACT FROM AUTHOR]

To enhance knowledge of the issues involved in the education and training of health professionals in health promotion, a focused but broad-based literature review took place. More than 70 studies of relevance were selected from the literature on human resource development and education, as well as professional preparation and development in health promotion. Studies reviewed covered current trends in initial professional education and training, continuing professional development, validation and accreditation, and evaluation. In none of these fields was there a significant literature based on systematic evaluation, but weaknesses in current practice were identified. A number of specific recommendations relating to the education and training of health professionals can be identified. These include: the importance of conceptual development and the capacity to reflect critically on practice; the value of efforts to bridge theory and practice through greater use of work-based systems of professional development; and the need to specify more clearly the health promotion role of health and education professionals so as to facilitate the development of appropriate methods of initial and continuing education and training. [ABSTRACT FROM AUTHOR]

Os defensores de abordagens baseadas no mercado para a educação invocam, às vezes, a necessidade de "empoderamento" (empowerment) das comunidades nas tomadas de decisão educacionais para justificar a reforma dos sistemas educacionais públicos convencionais. Com base em exemplos da Austrália, da Inglaterra e do País de Gales, da Nova Zelândia e dos eua, este artigo explora as maneiras complexas e contraditórias como as políticas educacionais contemporâneas usam o conceito de envolvimento das comunidades. Ele demonstra mais ainda que o papel e o impacto do envolvimento das comunidades nas escolas nada têm de simples. O artigo conclui que, se o envolvimento das comunidades quer ter efeitos progressistas, ele deve ser articulado com uma política de educação democrática mais ampla.

Osteopontin (Opn) is a phosphorylated glycoprotein, identified as an adhesive and migratory substrate for several cell types, which is highly expressed by osteoblasts within the hemopoietic stem cell (HSC) niche. We have previously demonstrated an unrecognized critical role for Opn in the regulation of the physical location and proliferation of HSC. Within the bone marrow the presence of Opn is restricted to the endosteal bone surface and we now have evidence that within this region, Opn exists in both the native as well as a cleaved form. In addition, we have shown that the cleaved form acts as a physiological negative regulator of HSC proliferation and differentiation through binding to both α[sub4]β[sub1] and α[sub9]β[sub1] integrins. We recently demonstrated for the first time the expression of α[sub9]β[sub1] on human HSC, with an inverse correlation between the expression of α[sub9]β[sub1] and CD38, demonstrating that this integrin is more abundantly expressed on more primitive HSC. In contrast α[sub4]β[sub1] expression mirrors that of CD38 and is expressed at higher levels on committed progenitors. Similarly, murine HSC also express α[sub9]β[sub1], with endosteal HSC exhibiting a higher level of expression compared to HSC from other bone marrow regions. Furthermore, we now have direct evidence of endogenous binding of Opn to both α[sub4]β[sub1] and α[sub9]β[sub1] on human cord blood HSC through coimmunoprecipitation experiments utilizing antibodies specific for α[sub4] and α[sub9]β[sub1]. In vitro, these cells specifically bind to OPN via both α[sub4] and α[sub9]β[sub1]. We have now explored the signalling pathways invoked following the interaction between OPN and these individual integrins expressed on HSC. Previous studies in other cellular systems have demonstrated that binding of ligands to α[sub9] specifically signals via either SSAT or paxillin to result in de-adhesion or augmented cell migration respectively. We have recently made the novel observation that human cord blood CD34+ cells and murine endosteal HSC and central HSC cells express SSAT and paxillin. Thus despite the high degree of homology exhibited by the α[sub4] and α[sub9] cytoplasmic domains, binding of each integrin by one ligand can give rise to specific functional responses, attributed to the association of distinct adapter and signalling proteins. These data provide strong evidence that Opn is an important component of the HSC niche, participating in the attraction and retention of HSC to this region, where it acts as a negative regulator of HSC proliferation and differentiation via binding to one of two integrins and invoking specific signalling. [ABSTRACT FROM AUTHOR]

Aim: Pilot clinical trial of NY-ESO-1 (ESO) protein in ISCOMATRIX™ adjuvant pulsed onto peripheral blood dendritic cells (PBDC), to ascertain feasibility, evaluate toxicity and assess induction of ESO-specific immune responses., Patients & Methods: Eligible participants had resected cancers expressing ESO or LAGE-1 and were at high risk of relapse. PBDC were produced using CliniMACS ® plus, with initial depletion of CD1c + B cells followed by positive selection of CD1c + PBDC. Patients received three intradermal vaccinations of ESO/IMX-pulsed PBDC at 4-week intervals., Results: The process was feasible and safe. No vaccine-induced immune responses were detected. Assays of immunomodulatory cells did not correlate with outcomes. One patient had a long lasting complete remission., Conclusion: This method was feasible and safe but was minimally immunogenic.

Previous studies revealed that mAb BB9 reacts with a subset of CD34(+) human BM cells with hematopoietic stem cell (HSC) characteristics. Here we map BB9 expression throughout hematopoietic development and show that the earliest definitive HSCs that arise at the ventral wall of the aorta and surrounding endothelial cells are BB9(+). Thereafter, BB9 is expressed by primitive hematopoietic cells in fetal liver and in umbilical cord blood (UCB). BB9(+)CD34(+) UCB cells transplanted into nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice contribute 10-fold higher numbers of multilineage blood cells than their CD34(+)BB9(-) counterparts and contain a significantly higher incidence of SCID-repopulating cells than the unfractionated CD34(+) population. Protein microsequencing of the 160-kDa band corresponding to the BB9 protein established its identity as that of somatic angiotensin-converting enzyme (ACE). Although the role of ACE on human HSCs remains to be determined, these studies designate ACE as a hitherto unrecognized marker of human HSCs throughout hematopoietic ontogeny and adulthood.

How diverse stimuli control hemopoietic lineage development is unknown. An early event during induction of macrophage differentiation in the myeloblastic leukemia M1 cell line by different stimuli, such as leukemia inhibitory factor (LIF) and interleukin-6 (IL-6), is expression of the colony-stimulating factor-1 receptor (CSF-1R). We report that expression of active CSF-1R in M1 cells accelerated their subsequent terminal differentiation into macrophages in response to LIF and IL-6 when compared with cells lacking the CSF-1R or expressing the receptor with compromised kinase activity; however, there was no requirement for signaling through the CSF-1R, for example, via endogenous CSF-1, during the actual LIF-induced and IL-6-induced differentiation stage. Differences were noted in the signaling pathways downstream of the LIF receptor depending on the presence of the CSF-1R. Both LIF and IL-6 gave an additive response with CSF-1, consistent with LIF and IL-6 acting via a different signaling pathway (signal transducer and activator of transcription 3 dependent) than CSF-1 (extracellular signal-regulated kinase dependent). Based at least on this cell model, we propose that terminal macrophage differentiation involves a critical priming or deterministic phase in which signaling by the CSF-1R prepares a precursor population for subsequent rapid terminal macrophage differentiation by diverse stimuli. We also propose that expression and activation of the CSF-1R explain much prior literature on macrophage lineage commitment in M1 leukemic cells and may be important in controlling the progression of certain myeloid leukemias.

Proteases and their serpin inhibitors are abundantly expressed in haemopoietic and peripheral blood cells. There is, however, relatively little information about the role played by serpins in the control of protease activity within these cells and in the pericellular region. The observation that mutations in the neutrophil elastase gene, which cause cyclic and severe congenital neutropenia, are associated with protease maldistribution gives some clue as to the potential importance of inhibitor proteins. To begin to address the role of protease/inhibitor balance in blood cells we used reverse transcription polymerase chain reaction to examine protease and serpin gene expression in mature peripheral blood cells, differentiating haemopoietic progenitors, leukaemic blasts and haemopoietic cell lines. The results demonstrate stage-specific expression of proteases together with widespread expression of intra- and extra-cellular serpins. The elastase inhibitors monocyte neutrophil elastase inhibitor (MNEI) and antitrypsin (AT) showed overlapping expression. MNEI is predominantly expressed in early haemopoietic progenitors while antitrypsin is mainly expressed in more mature myeloid precursors, peripheral blood granulocytes and mononuclear cells. Our results give an overall picture of serpin and protease gene expression and draws attention to the potential importance of elastase regulators at all stages of myelopoiesis.

Infusions of ex vivo-expanded (EXE) mobilized blood cells have been explored to enhance haematopoietic recovery following high dose chemotherapy (HDT). However, prior studies have not consistently demonstrated improvements in trilineage haematopoietic recovery. Three cohorts of three patients with breast cancer received three cycles of repetitive HDT supported by either unmanipulated (UM) and/or EXE cells. Efficacy was assessed by an internal comparison of each patient's consecutive HDT cycles, and to 106 historical UM infusions. Twenty-one cycles were supported by EXE cells and six by UM cells alone. Infusions of EXE cells resulted in fewer days with an absolute neutrophil count (ANC) <0.1 x 10(9)/l (median 2 vs. 4 d, P = 0.002) and 3 d faster ANC recovery to >0.1 x 10(9)/l (median 5 vs. 8 d, P = 0.0002). This resulted in a major reduction in the incidence of febrile neutropenia compared with UM cycles (0% vs. 83%; P = 0.008) and in 66% of historical UM cycles (P = 0.01) and a marked reduction in hospital re-admission. There were also fewer platelet transfusions required (43% vs. 100%; P = 0.009). We conclude that EXE cells enhance both neutrophil and platelet recovery and reduce febrile neutropenia, platelet transfusion and hospital re-admission.

Microglial cells, macrophage-lineage cells in the brain, are increased in amyloid-containing plaques in Alzheimer's disease (AD) and in the lesions of prion diseases. Recent studies suggest that microglia have a central role in turnover of amyloid in these diseases. We report here that synthetic amyloid beta (Abeta) 1-42 and prion protein (PrP) 106-126 peptides promote macrophage survival; they also induce macrophage DNA synthesis, particularly in the presence of sub-optimal concentrations of the growth factor, macrophage-colony stimulating factor (M-CSF or CSF-1). These responses are proposed to provide a means to increase brain microglia/macrophage numbers thereby enhancing subsequent inflammatory/immune responses. These fibrillogenic peptides join the list of aggregates having these effects on macrophages, indicating the generality of this type of response.

Osteoclasts form when hematopoietic cells are stimulated by macrophage colony-stimulating factor (M-CSF) and receptor activator of NF-kappaB ligand (RANKL) or tumor necrosis factor-alpha (TNFalpha). Osteoclast precursors derive from M-CSF-dependent proliferating hematopoietic cells but cannot yet be purified from mixed populations. M-CSF stimulation of bone marrow cells results in large numbers of nonadherent, proliferating macrophage precursors. These rapidly form adherent bone marrow macrophages (BMM). BMM and their precursors can be isolated free from mesenchymal and lymphocytic cells. BMM precursors derived from CBA-strain mouse bone marrow, when cocultured with ST2 cells (which express RANKL and M-CSF), formed numerous mononuclear osteoclasts, which resorbed bone and expressed tartrate-resistant acid phosphatase (TRAP) and calcitonin receptors (CTR). Addition of approximately 10 BMM precursors to ST2 cultures resulted in over 80% of these cocultures forming functional osteoclasts, suggesting that they are a highly enriched source of osteoclast progenitors. Supporting this, recombinant RANKL/M-CSF-stimulated BMM precursors formed populations in which all cells expressed TRAP. While only a small proportion of these cells (8.6%) expressed CTR, with transforming growth factor-beta (TGFbeta) present RANKL/M-CSF-stimulated BMM precursors formed almost pure (98.4%) CTR-positive osteoclasts after 7 days. This suggests that TGFbeta stimulated the maturation rate of these cells. Passaged or viably frozen BMM precursors gave rise to BMM that also all formed osteoclasts lineage cells after RANKL/M-CSF stimulation. These data suggest that BMM precursors derived from CBA mice are an expanded pool of osteoclast progenitors. These can be employed to generate osteoclast populations of high purity and in large numbers when stimulated by TGFbeta, which greatly augments the osteoclastogenic effects of RANKL.

M1 myeloid cells transfected with the wild-type (WT) colony-stimulating factor-1 (CSF-1) receptor (CSF-1R; M1/WT cells) undergo CSF-1-dependent macrophage differentiation. By mutation studies, we have provided prior evidence that tyrosine 559 in the CSF-1R cytoplasmic domain governs the Src-dependent differentiation pathway. Further components of this pathway were then sought. We report that the extent of CSF-1-mediated tyrosine phosphorylation of protein phosphatase 2A (PP2A), and the associated loss of its activity were reduced in M1 cells transfected with the CSF-1R with a tyrosine-to-phenylalanine mutation at position 559 (M1/559 cells), compared with the corresponding responses in CSF-1-treated M1/WT cells. This evidence for an involvement of a reduction in PP2A activity in the differentiation process was supported by the restoration of the defect in the CSF-1-mediated differentiation of M1/559 cells by the addition of the PP2A inhibitor, okadaic acid. It was also found that the degree of activation of extracellular-signal-regulated kinase (ERK) activities by CSF-1 was reduced in M1/559 cells, suggesting their involvement in the differentiation process. These data suggest that PP2A and ERK form part of the Src-dependent signal-transduction cascade governing CSF-1-mediated macrophage differentiation in M1 cells.

Macrophage colony stimulating factor (M-CSF or CSF-1) acts to regulate the development and function of cells of the macrophage lineage. Murine myeloid FDC-P1 cells transfected with the CSF-1 receptor (FD/WT) adopt a macrophage-like morphology when cultured in CSF-1. This process is abrogated in FDC-P1 cells transfected with the CSF-1 receptor with a tyrosine to phenyalanine substitution at position 807 (FD/807), suggesting that a molecular interaction critical to differentiation signaling is lost (Bourette, R. P., Myles, G. M., Carlberg, K., Chen, A. R., and Rohrschneider, L. R. (1995) Cell Growth Differ. 6, 631--645). A detailed examination of lysates of CSF-1-treated FD/807 cells by two-dimensional SDS-polyacrylamide gel electrophoresis (PAGE) revealed a number of proteins whose degree of tyrosine phosphorylation was modulated by the Y807F mutation. Included in this category were three phosphorylated proteins that co-migrated with p46/52(Shc). Immunoprecipitation, Western blotting, and in vitro binding studies suggest that they are indeed p46/52(Shc). A key regulator of differentiation in a number of cell systems, ERK was observed to exhibit an activity that correlated with the relative degree of differentiation induced by CSF-1 in the two cell types. Transfection of cells with a non-tyrosine-phosphorylatable form of p46/52(Shc) prevented the normally observed CSF-1-mediated macrophage differentiation as determined by adoption of macrophage-like morphology and expression of the monocyte/macrophage lineage cell surface marker, Mac-1. These results are the first to suggest that p46/52(Shc) may play a role in CSF-1-induced macrophage differentiation. Additionally, a number of proteins were identified by two-dimensional SDS-PAGE whose degree of tyrosine phosphorylation is also modulated by the Y807F substitution. This group of molecules may contain novel signaling molecules important in macrophage differentiation.