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Query: UNIPROT:P04141 (
granulocyte-macrophage colony-stimulating factor
)
6,790
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
IL-12 production in HIV-infected (HIV+) individuals is severely impaired after stimulation by bacterial products or T cell-dependent stimuli. Because
CD40
-CD40 ligand (CD40L) interactions are the major mechanism involved in the T cell-dependent activation of antigen-presenting cells, we investigated whether this pathway was functional in HIV+ donors.
CD40
expression was increased on freshly isolated monocytes from HIV+ individuals compared to HIV donors. However, equivalent
CD40
expression was obtained in the two groups after cytokine stimulation. Since
CD40
expression was intact in HIV+ donors' cells, we determined whether IL-12 production could be restored by providing exogenous T cell-dependent stimuli, CD40L and IFN-gamma, at the time of bacterial stimulation. IL-12 production was not altered by CD40L alone, was increased by IFN-gamma, and was synergistically restored to normal values by IFN-gamma + CD40L. This combination was more efficient for enhancing IL-12 production than
granulocyte-macrophage colony-stimulating factor
+ CD40L or neutralizing anti-IL-10 antibody + CD40L. CD40L did not affect IL-10 production, whereas IFN-gamma significantly decreased it. This study demonstrates that the defect in IL-12 production by leukocytes from HIV+ donors can be overcome in vitro if the interacting cells are provided with the right T cell-dependent co-stimuli.
...
PMID:CD40 ligand and IFN-gamma synergistically restore IL-12 production in HIV-infected patients. 952 Oct 75
Exposure to UVB results in the isomerization of trans-urocanic acid (UCA), localized in the stratum corneum, to cis-UCA. Cis-UCA can mediate at least some of the immunosuppressive effects of UVB, though the mechanism of cis-UCA action remains incompletely defined. Alterations in Langerhans cells, and other dendritic antigen presenting cell populations in the skin, may contribute to the loss of skin immune function following UVB exposure. Hence, this study was designed to investigate whether cis-UCA directly can induce changes in the immunostimulatory capacity of dendritic cells (DC) and the development of DC from precursor cells. Murine DC were generated from C57BL/6 bone marrow (BM) using
granulocyte-macrophage colony-stimulating factor
(
GM-CSF
), and were used as stimulator cells in mixed lymphocyte reactions (MLR) using BALB/c lymph node cells (LNC) as responders. The addition of cis- and trans-UCA at concentrations ranging from 0.1-500 micrograms/ml to the MLR did not affect proliferative responses. Cis- or trans-UCA (100 micrograms/ml) was added to
GM-CSF
stimulated mouse BM cells on day 0, day 3 or day 5 of culture, and the phenotype and allo-stimulatory function of the DC were analysed on day 7. Treatment with cis- or trans-UCA did not affect the numbers or the viability of cells in the BM cultures. In addition, the expression on DC of Iab, CD11c or the costimulatory molecules ICAM-1, B7-1, B7-2 and
CD40
was not altered by the addition of cis-UCA to BM cultures. The inability of cis-UCA to alter the development of DC in vitro was confirmed by analysing the functional capacity of DC in MLR. DC generated in the presence of cis-UCA were equally efficient in the induction of allo-stimulation, when compared with control DC. These results suggest that cis-UCA does not exert its immunosuppressive activity through direct effects on DC. Such activity may be independent of DC, or alternatively, cis-UCA may influence DC function indirectly, through the induction of secondary mediators.
...
PMID:Physiologic doses of urocanic acid do not alter the allostimulatory function or the development of murine dendritic cells in vitro. 954 50
We have recently established the culture system to generate dendritic cells (DCs) from murine Lin-c-kit+ bone marrow hematopoietic progenitor cells (HPCs) in the presence of
granulocyte-macrophage colony-stimulating factor
(
GM-CSF
) + stem cell factor (SCF) + tumor necrosis factor-alpha (TNF-alpha). We present here the identification of two DC precursor subsets originated from HPCs with the phenotype of CD11b-/dullCD11c+ and CD11b+hiCD11c+ that develop independently at early time points (days 4 to 6) in the same culture conditions. Both of CD11b-/dullCD11c+ and CD11b+hiCD11c+ precursors could differentiate at day 10 to 14 into CD11b-/dullCD11c+ mature DCs with typical morphology, phenotype, and the ability to stimulate allogenic mixed leukocyte reaction (MLR). However, the endocytic capacity of fluorescein isothiocyanate-dextran was markedly reduced during the differentiation. CD11b-/dullCD11c+ precursors expressed high levels of Ia, CD86,
CD40
, and E-cadherin molecules, but not c-fms transcript, and mature DCs derived from this precursor subset continue to express abundant E-cadherin antigen, a discernible marker for Langerhans cells. In contrast, CD11b+hiCD11c+ precursors expressed c-fms mRNA, but low levels of Ia, CD86, and E-cadherin, whereas
CD40
was undetectable. CD11b-/dullCD11c+ mature DCs differentiated from these precursors displayed abundant c-fms mRNA and nonspecific esterase activity. Interestingly, CD11b+hiCD11c+ precursors, but not CD11b-/dullCD11c+ precursors, may be bipotent cells that can be induced by M-CSF to differentiate into macrophages. All of these results suggest that CD11b-/dullCD11c+ and CD11b+hiCD11c+ cells are distinct DC precursors derived from Lin-c-kit+ HPCs, which differentiate into mature DCs through bifurcated and independent DC differentiation pathways.
...
PMID:Bifurcated dendritic cell differentiation in vitro from murine lineage phenotype-negative c-kit+ bone marrow hematopoietic progenitor cells. 963 7
Thymic nurse cells are known to interact with T cells and play a role in their functional maturation. However, the role of nurse cells in B cell maturation and differentiation is less well established, especially at extralymphoid sites. To address this issue, nurse-like cell clones from bone marrow and synovial tissue of patients with RA (RA-NLC) were established and characterized. RA-NLC constitutively expressed CD29, CD49c, CD54 (ICAM-1), CD106 (VCAM-1), CD157 (BST-1), and class I MHC molecules, and secreted IL-6, IL-7, IL-8,
granulocyte-macrophage colony-stimulating factor
(
GM-CSF
) and granulocyte colony-stimulating factor (G-CSF). Bone marrow-derived and synovial RA-NLC differed in that the former secreted IL-7 and expressed a greater density of CD157 constitutively and after stimulation with IFNgamma, whereas the latter secreted G-CSF and more IL-6. Stimulation of both bone marrow and synovial RA-NLC induced expression of
CD40
and class II MHC, but not CD154 (CD40L) or CD35. RA-NLC rescued peripheral B cells from spontaneous apoptosis and promoted survival of B cells for > 4 wk. B cell survival was blocked by antibodies to CD106 or CD157. RA-NLC also increased Ig production from B cells. After long-term culture (4-6 wk) with RA-NLC, but not alone or with fibroblasts, outgrowth of B cells was observed. All B cell lines derived from these cultures had been transformed by EBV, although the RA-NLC themselves were not infected with EBV. Precursor frequency analysis indicated that approximately 1 in 12,500 peripheral B cells could give rise to these EBV-transformed B cell lines upon coculture with RA-NLC. These results indicate that RA-NLC from bone marrow and synovium have the capacity to rescue B cells from spontaneous apoptosis, facilitate Ig production, and promote the outgrowth of EBV-transformed B lymphoblastoid cells. These findings suggest that RA-NLC may play a role in the local and systemic hyperreactivity of B cells characteristic of rheumatoid arthritis.
...
PMID:Nurse-like cells from bone marrow and synovium of patients with rheumatoid arthritis promote survival and enhance function of human B cells. 969 Oct 97
We examined the effect of interleukin (IL)-4 or
CD40
ligation on the differentiation and maturation of CD1a+CD14- and CD1a-CD14+ dendritic cell (DC) precursors. Cord blood CD34+ cells were cultured with
granulocyte-macrophage colony-stimulating factor
(
GM-CSF
) and tumor necrosis factor alpha (TNF-alpha), to which stem cell factor and Flt-3 ligand were added for 5 days. Phenotypic analysis of DC precursors on culture day 7 showed that CD1a+CD14- cells expressed higher CD11c and CD80 levels and lower CD116/GM-CSFR and CCR-5 levels than their CD1a-CD14+ counterparts. Culturing CD1a+CD14- precursors with
GM-CSF
and TNF-alpha resulted in DC with heterogeneous CD1a, HLA;SMDR (DR), CD11b, and CD83 expression, 10% of which acquired CD14. IL-4 and
CD40
ligation affected their differentiation in contrasting ways: IL-4 induced CD1ahiCD14-DRloCD11b+CD83-S100+ DC with reduced MLR-stimulating capacity, whereas
CD40
ligation led to CD1alo/-CD14-
CD40
-DRhiCD11b-CD83+S100+/- DC with stronger MLR-stimulating capacity. Also, both IL-4 and
CD40
ligation promoted ReIB expression and nuclear translocation. When CD1a-CD14+ precursors were maintained in only the presence of
GM-CSF
and TNF-alpha, this led to mixed populations of adherent macrophages and nonadherent CD1a-CD14+ monocytes, and of CD1a+CD14- and CD1a+CD14+ DC, which were DRloCD11b+CD83-S100-. IL-4 or
CD40
ligation prevented their differentiation into macrophages and resulted in DC with phenotypes close to those issued from CD1a+CD14- precursors, with only a minority staying CD14+ but most being S100-; their MLR-stimulating capacity also increased but remained lower than that of DC differentiated from CD1a+CD14- precursors. Thus, IL-4 or
CD40
ligation induced CD1a+CD14- and CD1a-CD14+ DC precursors to differentiate into phenotypically close but functionally different DC populations, suggesting that DC function is primarily determined by their origin. The heterogeneity of DC should then be related to different developmental pathways and to different stages of maturation/activation.
...
PMID:IL-4 and CD40 ligation affect differently the differentiation, maturation, and function of human CD34+ cell-derived CD1a+CD14- and CD1a-CD14+ dendritic cell precursors in vitro. 971 64
Dendritic cells (DC) can be generated by culture of adherent peripheral blood (PB) cells in the presence of
granulocyte-macrophage colony-stimulating factor
(
GM-CSF
) and interleukin-4 (IL-4). There is controversy as to whether these DC arise from proliferating precursors or simply from differentiation of monocytes. DC were generated from myeloid-enriched PB non-T cells or sorted monocytes. DC generated from either population functioned as potent antigen-presenting cells. Uptake of [3H]-thymidine was observed in DC cultured from myeloid-enriched non-T cells. Addition of lipopolysaccharide or tumor necrosis factor-alpha led to maturation of the DC, but did not inhibit proliferation. Ki67(+) cells were observed in cytospins of these DC, and by double staining were CD3(-)CD19(-)CD11c-
CD40
(-) and myeloperoxidase+, suggesting that they were myeloid progenitor cells. Analysis of the starting population by flow cytometry demonstrated small numbers of CD34(+)CD33(-)CD14(-) progenitor cells, and numerous granulocyte-macrophage colony-forming units were generated in standard assays. Thus, production of DC in vitro from adherent PB cells also enriches for progenitor cells that are capable of proliferation after exposure to
GM-CSF
. Of clinical importance, the yield of DC derived in the presence of
GM-CSF
and IL-4 cannot be expanded beyond the number of starting monocytes.
...
PMID:Proliferation in monocyte-derived dendritic cell cultures is caused by progenitor cells capable of myeloid differentiation. 971 87
The diverse roles of interferon-alpha (IFN-alpha) in regulating the immune response to infectious agents suggested that it might affect dendritic cell (DC) development. Peripheral blood mononuclear cells cultured with IFN-alpha and
granulocyte-macrophage colony-stimulating factor
(
GM-CSF
) developed a dendritic morphology and expressed high levels of the class I and II human leukocyte antigens (HLA), B7 co-stimulatory molecules, adhesion proteins, and
CD40
. Elevated DC expression of B7-2 and HLA-DR was observed with increasing IFN-alpha concentrations up to 5000 U/mL. The effects of IFN-alpha on DC immunophenotype were not reversed by adding neutralizing antibodies against interleukin-4 (IL-4) or tumor necrosis factor alpha to the cell cultures or by eliminating lymphocytes from the cultures. The addition of IFN-alpha to cultures containing optimal concentrations of IL-4 and
GM-CSF
significantly increased the B7-2 and HLA-DR levels above those present on DCs grown in two cytokines. The DCs generated with IFN-alpha and
GM-CSF
were potent antigen-presenting cells in allogeneic mixed leukocyte reactions. They also were capable of taking up, processing, and presenting tetanus toxin to autologous T lymphocytes. These results demonstrate an important role for IFN-alpha in the generation of DCs with potent antigen-presenting capabilities from peripheral blood monocytes.
...
PMID:Interferon-alpha and granulocyte-macrophage colony-stimulating factor differentiate peripheral blood monocytes into potent antigen-presenting cells. 973 63
The B cell line, MRL159.5, was established by somatic hybridization between splenic MRL/MP-lpr/lpr (lpr) mice B cells and 2.52M, a hypoxanthine-aminopterine-thymidine (HAT) medium-sensitive B cell line mutant. It possessed a receptor molecule for mouse erythrocytes treated with bromelain (Br-MRBC) on its surface, likely to be an autoreactive B cell clone specific for Br-MRBC as detected by rosette-forming assay with Br-MRBC. MRL159.5 spontaneously produced IL-6 and secreted IgM, and was induced to augment IgM secretion when treated with Br-MRBC or IL-6. Triggering of
CD40
led to an augmentation of IgM secretion as well as IL-6 expression. Blocking the binding of IL-6 to its cellular receptor through the use of inhibitory antibodies inhibited
CD40
-induced IgM secretion, suggesting a possible autocrine role of IL-6 for
CD40
-induced differentiation of this B cell hybridoma. Addition of IL-4 or Br-MRBC augmented IL-6 expression as well as IgM secretion by
CD40
-activated MRL159.5 cells.
CD40
also augmented tumour necrosis factor-alpha (TNF-alpha) and
granulocyte-macrophage colony-stimulating factor
(
GM-CSF
) expression but resulted in decreased IL-10 expression. Furthermore, under conditions where IL-6 expression was augmented, IL-6R alpha (gp80) expression was down-regulated, suggesting a negative feedback mechanism of an IL-6 autocrine loop in this hybridoma. These results demonstrate a role by which T cell-dependent activation through
CD40
regulates an IL-6 autocrine loop, controlling differentiation of autoreactive B cells in autoimmune disease.
...
PMID:Regulation of cytokine expression by an autoreactive B cell clone derived from MRL/MP-lpr/lpr mice. 976 95
Recently it has been shown that dendritic cells (DC) can develop from peripheral blood monocytes when grown in the presence of
granulocyte-macrophage colony-stimulating factor
(
GM-CSF
) and interleukin-4 (IL-4). However, it is unclear whether DC can also develop from monocytes in absence of these cytokines. We therefore analyzed the effect of Flt-3 ligand (Flt3L) and of CD40 ligand on the development of human DC from blood monocytes in the absence of
GM-CSF
. Adherent peripheral blood mononuclear cells (PBMNC) were cultured in the presence of different cytokine combinations and analyzed for the expression of surface molecules and antigen presenting capacity. For functional analyses, cells were tested for their ability to stimulate allogeneic T lymphocytes in a mixed lymphocyte reaction (MLR), to present soluble antigens, and to induce primary HIV-peptide-specific cytotoxic T-cell (CTL) responses in vitro. Furthermore, expression of DC-CK1, a recently identified chemokine with specific expression in DC, and of IL-18 (IGIF), a growth and differentiation factor for Th 1 lymphocytes, was analyzed by reverse-transcription polymerase chain reaction (RT-PCR). In our study, Flt3L alone was not sufficient to generate DC and required addition of IL-4. DC generated with Flt3L and IL-4 underwent maturation after stimulation with tumor necrosis factor- (TNF-) or CD40L, characterized by CD83 expression, upregulation of MHC, adhesion, and costimulatory molecules as well as increased allogeneic proliferative response. In contrast,
CD40
ligation alone promoted differentiation of adherent blood monocytes into functional DC in the absence of
GM-CSF
and IL-4. These cells displayed all phenotypic and functional characteristics of mature DC and were potent stimulatory cells in priming of major histocompatibility complex (MHC) class I-restricted CTL responses against an HIV-peptide, whereas their ability to present soluble protein antigens was reduced. Using a semiquantitative RT-PCR, DC-CK1 and IL-18 transcripts were detected in all generated DC populations, independent of growth factors used. Our findings provide further evidence for the importance of
CD40
-CD40L interaction for initiation and maintenance of T-cell responses and confirm the emerging concept that blood monocytes provide an additional source of DC depending on external stimuli.
...
PMID:Generation of functional human dendritic cells from adherent peripheral blood monocytes by CD40 ligation in the absence of granulocyte-macrophage colony-stimulating factor. 983 29
Since dendritic cells (DCs) are the most professional antigen-presenting cells, (Schuler et al., 1997), increasing interest in their use in clinical approaches has been observed. (Nestle et al., 1998; Murphy G. et al., 1996). We have developed an ex vivo standardized process for the generation of dendritic-like cells (MAC-DCs) from human blood circulating monocytes. Human monocytes can differentiate into very different functional cells according to the conditions of culture, media and cytokines used. In the present study, we demonstrate that both pure monocytes and mononuclear cells differentiate into DCs when they are grown in defined medium AIM-V in the presence of
granulocyte-macrophage colony-stimulating factor
(
GM-CSF
) plus IL13 and in approved biocompatible non-adherent bags. Quality and functional controls of the immature DCs obtained rely on bacterial sterility, viability, morphology and recovery. The MAC-DCs also present an immature DC phenotype with a low expression of CD14 and CD64, and high expression of MHC-I, MHC-II and
CD40
. They also express B7 costimulatory molecules (CD80, CD86), CD83, and CD1a molecules. They induce strong allogenic T-cell proliferation (mixed lymphocyte reaction as well as proliferation of autologous memory T lymphocytes when incubated in the presence of recall antigens (tuberculosis, Candida albicans, and tetanus toxoid). They also show an increase in phagocytic uptake of yeast, tumour cells and debris. The global closed system which, under reproducible good medical practice (GMP) conditions, enables the production of dendritic cells of clinical quality, has been optimized ("Vac Cell Processor"). It contains all bags, connections, media, reagents, washing solutions, control antibodies, standard operating procedures, data management, traceability and help in the form of dedicated software.
...
PMID:Monocyte-derived dendritic cells: development of a cellular processor for clinical applications. 985 16
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