Regulated On Activation, Normal T Expressed And Secreted Research Articles

Enhanced production of MMP-1, MMP-3, MMP-13, and RANTES by interaction of chondrocytes with autologous T cells

It has been reported that T cells and chondrocytes interact through cell surface molecules such as MHC, CD4 or CD8 in osteoarthritis (OA) and T cells are activated. The objective of this study is to investigate the responses of chondrocyte-T cell interaction in terms of metalloprotease (MMP) and chemokine production. Articular cartilage and autologous blood were obtained from patients with OA and fracture who under went prosthetic surgery. Synovial fluid (SF) was collected from OA patients. Isolated chondrocytes were co-cultured with autologous T cells. SF cells were analyzed by immunostaining or Alcian blue staining. The production of MMP-1, MMP-3, MMP-13, and regulated on activation, normal T expressed and secreted (RANTES) was enhanced by direct co-culture compared to indirect co-culture using Transwell. Production ratio of RANTES in OA was significantly higher than non-arthritic samples. CD3 positive mononuclear cells and chondrocyte-like cells were found in SF. Chondrocyte-T cell contact was more adhesive in OA samples. These results showed the production of MMPs and RANTES was enhanced by the interaction and that chondrocyte-T cell contact was possible in vivo.

RANTES Production from Mononuclear Cells in Response to the Specific Allergen in Asthma Patients

Eosinophils are considered to be the major inflammatory cells in asthma. Since regulated on activation, normal T expressed and secreted (RANTES) is a potent chemoattractant for various important inflammatory cells such as eosinophils as well as memory T cells potentially recruiting these cells to an inflamed focus, RANTES has been considered to play a key role in various allergic disorders such as asthma. To extend our understanding of the participation of eosinophils and T cells in relation to the production of RANTES in response to the specific allergen in asthma, we examined the production of RANTES from peripheral blood mononuclear cells cultured with specific allergen in atopic asthma patients by a sandwich enzyme-linked immunosorbent assay. It was revealed that mononuclear cells produced RANTES but not eotaxin in response to the specific allergen in asthma. RANTES production from mononuclear cells of asthma patients with eosinophilia was greater than that of asthma patients without eosinophilia. Moreover, in this study, no differences in RANTES production between CD4 negative cells and CD8 negative cells were observed. Taken together, these findings may suggest that mononuclear cells play a crucial role in the pathogenesis, particular in eosinophil and T lymphocyte recruitment into the inflamed focus of asthma through RANTES production in response to the specific allergen.

Protease-dependent activation of nasal polyp epithelial cells by airborne fungi leads to migration of eosinophils and neutrophils

Conclusions. Proteases in fungi interact with nasal epithelial cells and enhance the production of inflammatory cytokines in vitro. These cytokines induced the migration of eosinophils and neutrophils. Protease-activated receptors (PARs) might also play a role in the process of epithelial cell activation. Objective. The nasal epithelium is the first barrier encountered by airborne allergens and an active participant in airway inflammation. Fungi have been increasingly recognized as important pathogens in sinusitis and consist of several allergenic proteins. Materials and methods. Nasal polyp epithelial cells were obtained from patients and stimulated with Alternaria, Aspergillus, and Cladosporium. Interleukin-8 (IL-8), granulocyte-macrophage colony stimulating factor (GM-CSF), and regulated on activation normal T expressed and secreted (RANTES) were measured to determine the activation of epithelial cells. Reverse transcriptase-polymerase chain reaction test (RT-PCR) for PAR mRNA expression in nasal epithelial cells was performed. Eosinophil and neutrophil migration was induced with nasal polyp epithelial cells conditioned media (HPECM). Results. Fungi enhanced the production of chemical mediators from nasal epithelial cells. When nasal epithelial cells were activated with fungi, PAR2 and PAR3 mRNAs were more strongly expressed than in nonactivated cells. Eosinophil migration was induced by RANTES and eotaxin, and neutrophil migration was induced by IL-8 in HPECM.

Involvement of CCR5 in the passage of Th1-type cells across the blood-retina barrier in experimental autoimmune uveitis

Although the recruitment of T helper cell type 1 (Th1)/Th2 cells into peripheral tissues is essential for inflammation and the host response to infection, the traffic signals that enable the distinct positioning of Th1/Th2 cells are unclear. We have determined the role of CC chemokine receptor 5 (CCR5) in this using experimental autoimmune uveitis (EAU) as a model system. In EAU, Th1-like cells are preferentially recruited into the retina across the blood-retina barrier, partly as a result of expression of the adhesion molecules P-selectin glycoprotein ligand 1 and lymphocyte function-associated antigen-1 on these cells. CD3+ T cells, infiltrating the retina, also expressed the chemokine receptor CCR5, and CCR5 ligands, macrophage-inflammatory protein-1alpha (MIP-1alpha), MIP-1beta, and regulated on activation, normal T expressed and secreted (RANTES), were strongly expressed in the retina at peak EAU. Th1-like cells, polarized in vitro, expressed high levels of CCR5. The trafficking of these CCR5+ cells was examined by tracking them after adoptive transfer in real time in vivo at an early disease stage using scanning laser ophthalmoscopy. Treatment of the cells with antibody against CCR5 prior to transfer resulted in a reduction in their infiltration into the retina. However, rolling velocity, rolling efficiency, and adherence of the cells to retinal endothelium were not reduced. CCR5 is clearly important for Th1 cell recruitment, and this study demonstrates for the first time in vivo that CCR5 may act at the level of transendothelial migration rather than at the earlier stage of rolling on the endothelium.

Phenotypic and functional profiling of human proinflammatory type-1 and anti-inflammatory type-2 macrophages in response to microbial antigens and IFN-γ- and CD40L-mediated costimulation

Macrophages (Mphi) comprise a heterogeneous population of cells with various immune and homeostatic functions. Recently, we have described type-1 and type-2 human monocyte-derived Mphi subsets. Although both support outgrowth of intracellular mycobacteria, Mphi-1 secretes interleukin (IL)-23/IL-12 and supports T helper cell type 1 (Th1) responses, whereas Mphi-2 fails to produce IL-23/IL-12, predominantly secretes IL-10, and inhibits Th1 function. Here, we further describe the phenotypic and functional profiles of Mphi-1 and Mphi-2 in response to microbial antigens and interferon-gamma (IFN-gamma) and CD40L as costimulatory T cell back-talk signals. Activated IL-23(+)/IL-12(+) Mphi-1 secreted IL-1beta, IL-18, IL-6, and tumor necrosis factor-alpha (TNF-alpha), as well as IL-8, monocyte chemoattractant protein-1 (MCP-1), IFN-inducible protein 10 (IP-10), Mphi inflammatory protein-1beta (MIP-1beta), regulated on activation, normal T expressed and secreted (RANTES), Mphi-derived chemokine (MDC), and (low levels of) pulmonary and activation-regulated chemokine and thymus and activation-regulated chemokine (TARC), corroborating their proinflammatory function. Regardless of the stimulus, Mphi-2 maintained their IL-10(+) signature cytokine profile and produced no or relatively low levels of IL-12p40, IL-1beta, IL-6, TNF-alpha, MDC, or TARC. It is remarkable that Mphi-2 secreted high levels of IL-8, MCP-1, IP-10, MIP-1beta, and RANTES, suggesting an active role for these cells in regulating cellular immunity and homeostasis. Mphi-1 and Mphi-2 expressed similar levels of Toll-like receptor and dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin as microbial pattern recognition receptors. Mphi-2, unlike Mphi-1 but like other nonclassical Mphi described previously, expressed CD163 and down-modulated human leukocyte antigen and costimulatory molecules specifically upon activation. These findings demonstrate how Mphi-1/Mphi-2 polarization can differentially skew the host response toward pro- or anti-inflammatory immune responses, respectively. This is likely to be relevant for host-pathogen interactions in chronic bacterial infections and provides a model for dissecting pro- and anti-inflammatory cascades.

Expression of Chemokine Receptors CCR5 and CXCR4 on CD4+ T Cells and Plasma Chemokine Levels During Treatment of Active Tuberculosis in HIV-1-Coinfected Patients

The pathogenesis of persistently elevated plasma HIV viremia in patients coinfected with tuberculosis (TB) during anti-TB treatment in Africans remains unknown. We examined the expression of chemokine receptors CCR5 and CXCR4 on CD4+ T cells and plasma chemokine levels of macrophage inflammatory protein (MIP)-1alpha, MIP-1beta, regulated on activation normal T expressed and secreted (RANTES), and stromal cell-derived factor (SDF)-1alpha among TB patients with HIV coinfection during the first 2 months of anti-TB treatment. During treatment of TB, the plasma HIV-1 load and CD4+ T-cell count remained unchanged. Levels of CCR5 and CXCR4 expression on CD4+ T cells as well as plasma levels of chemokines remained persistently elevated during anti-TB treatment. Persistently elevated plasma HIV viremia also paralleled persistently elevated expressions of activated CCR5+ or CXCR4+ CD4+ T cells. These results suggest that increased expression of CCR5 and CXCR4 on an activated CD4+ T-cell population coupled with persistently elevated chemokines may provide a suitable condition for continuous replication of HIV associated with TB coinfection. This, in turn, may contribute, at least in part, to the observed persistently elevated plasma HIV viremia in coinfected patients despite anti-TB treatment.

MIP-1α[CCL3] acting on the CCR1 receptor mediates neutrophil migration in immune inflammation via sequential release of TNF-α and LTB4

In the present study, we investigated the involvement of macrophage-inflammatory protein-1alpha (MIP-1alpha)[CC chemokine ligand 3 (CCL3)], MIP-1beta[CCL4], regulated on activation, normal T expressed and secreted (RANTES)[CCL5], and CC chemokine receptors (CCRs) on neutrophil migration in murine immune inflammation. Previously, we showed that ovalbumin (OVA)-triggered neutrophil migration in immunized mice depends on the sequential release of tumor necrosis factor alpha (TNF-alpha) and leukotriene B(4)(LTB(4)). Herein, we show increased mRNA expression for MIP-1alpha[CCL3], MIP-1beta[CCL4], RANTES[CCL5], and CCR1 in peritoneal cells harvested from OVA-challenged, immunized mice, as well as MIP-1alpha[CCL3] and RANTES[CCL5] but not MIP-1beta[CCL4] proteins in the peritoneal exudates. OVA-induced neutrophil migration response was muted in immunized MIP-1alpha[CCL3](-/-) mice, but it was not inhibited by treatment with antibodies against RANTES[CCL5] or MIP-1beta[CCL4]. MIP-1alpha[CCL3] mediated neutrophil migration in immunized mice through induction of TNF-alpha and LTB(4) synthesis, as these mediators were detected in the exudates harvested from OVA-challenged immunized wild-type but not MIP-1alpha[CCL3](-/-) mice; administration of MIP-1alpha[CCL3] induced a dose-dependent neutrophil migration, which was inhibited by treatment with an anti-TNF-alpha antibody in TNF receptor 1 (p55(-/-))-deficient mice or by MK 886 (a 5-lipoxygenase inhibitor); and MIP-1alpha[CCL3] failed to induce LTB(4) production in p55(-/-) mice. MIP-1alpha[CCL3] used CCR1 to promote neutrophil recruitment, as OVA or MIP-1alpha[CCL3] failed to induce neutrophil migration in CCR1(-/-) mice, in contrast to CCR5(-/-) mice. In summary, we have demonstrated that neutrophil migration observed in this model of immune inflammation is mediated by MIP-1alpha[CCL3], which via CCR1, induces the sequential release of TNF-alpha and LTB(4). Therefore, whether a similar pathway mediates neutrophil migration in human immune-inflammatory diseases, the development of specific CCR1 antagonists might have a therapeutic potential.

Regulated expression of platelet factor 4 in human monocytes—role of PARs as a quantitatively important monocyte activation pathway

Human mononuclear phagocytes have recently been shown to express constitutively and even more so, upon stimulation with bacteria, fungi, lipopolysaccharide (LPS), zymosan, or thrombin platelet basic protein (PBP). This CXC chemokine as well as platelet factor 4 (PF4), which is located genomically at a short distance from the PBP, were previously considered to be specific markers for the megakaryocyte cell lineage. Both chemokines have signaling and antimicrobial activity. In the present studies, transcriptional and expressional regulation of PF4 and related chemokines was studied in human monocytes. As shown by quantitative mRNA analysis, Western blots, radioimmunoprecipitation of cell extracts, and immunofluorescence and quantitatively with enzyme-linked immunosorbent assay, human monocytes express PF4 in the same order of magnitude as the known, regulated CXC chemokine interleukin (IL)-8. Expression of PF4 is up-regulated at the mRNA and protein level by thrombin and mediated by proteinase-activated receptors (PARs), resulting in a 32- to 128-fold higher mRNA level and leading to an up-to-sixfold increase of the peptide concentration in monocyte culture supernatants. Thrombin and the synthetic ligand of PAR-1 and PAR-2, SFLLRN, also induced comparable increases in the levels of mRNA for PBP, IL-8, regulated on activation, normal T expressed and secreted (RANTES), monocyte chemoattractant protein-1, and macrophage-inflammatory protein-1alpha and increased synthesis of these chemokines as shown by immunofluorescence or a quantitative immunobead-based method. The induction of increased mRNA levels for all chemokines by SFLLRN was unsurpassed by LPS, zymosan, interferon-gamma (IFN-gamma), tumor necrosis factor alpha (TNF-alpha), and IL-1. Activation of monocytes through PARs represents an alternate activation mechanism, independent from IFN-gamma, TNF-alpha, or other signaling pathways.

Disruption of granulocyte macrophage-colony stimulating factor production in the lungs severely affects the ability of mice to controlMycobacterium tuberculosisinfection

Mice lacking expression of granulocyte macrophage-colony stimulating factor (GM-CSF KO) are unable to contain Mycobacterium tuberculosis (M. tuberculosis) growth and succumb to infection by 35 days following pulmonary challenge. GM-CSF KO mice do not express normal levels of the inflammatory cytokine tumor necrosis factor alpha (TNF-alpha) nor the chemokines, regulated on activation, normal T expressed and secreted (RANTES), macrophage-inflammatory protein-1beta (MIP-1beta), MIP-1alpha, and lymphotactin, which are required for recruitment of lymphocytes and expression of a T helper cell type 1 (TH1) response within the lungs. In contrast, transgenic mice overexpressing GM-CSF in the lungs but with a lack of GM-CSF in other organs (GM+) are able to recruit lymphocytes and to express a TH1 response with production of TNF-alpha and interferon-gamma in the lungs. However, GM+ mice succumb to infection between 60 and 90 days post-challenge, as they are unable to develop a normal granulomatous response. Although GM+ mice are able to express the chemokine RANTES, they lack the ability to express other inflammatory chemokines such as lymphotactin and MIP-1beta. We conclude that GM-CSF is essential to the recruitment of lymphocytes and expression of a TH1 response in the lung, to the generation of a normal mononuclear granuloma, and most importantly, to the containment of M. tuberculosis bacterial growth.

Lack of Association between Atopic Dermatitis and -401A/G Polymorphism in the Promoter Region of the RANTES Gene in Japanese

ABSTRACT Background Regulated on activation, normal T expressed and secreted (RANTES) has been known to be deeply involved in the pathophysiology of atopic dermatitis (AD). To examine whether a –401A/G polymorphism in the RANTES promoter gene is associated with the susceptibility to AD in Japanese, we determined the genotypes of the polymorphism in 145 Japanese students and 65 patients with AD. Methods DNA was isolated from the mononuclear cells by using SepaGene (Sanko) and analyzed by the polymerase chain reaction (PCR) technique. Results The frequency of –401A allele was 0.39 in the healthy subjects without AD. This was not significantly different from that in the patients with AD (0.41). We also failed to show association between the polymorphism in the RANTES promoter gene and the production of IgE. Conclusions These results suggest that the –401A/G polymorphism in the RANTES promoter gene does not determine the susceptibility to AD in Japanese, although larger studies could explore the exact role of the polymorphisms in AD, or Japanese might have other susceptibility genes more potent than the RANTES promoter gene.

Chemokine expression during the development and resolution of a pulmonary leukocyte response to influenza A virus infection in mice

Influenza A virus replicates in the respiratory epithelium and induces an inflammatory infiltrate comprised of mononuclear cells and neutrophils. To understand the development of the cell-mediated immune response to influenza and how leukocyte trafficking to sites of inflammation is regulated, we examined the chemokine expression pattern in lung tissue from A/PR/8/34-infected C57BL/6 mice using an RNase protection assay. Monocyte chemoattractant protein 1, macrophage inflammatory protein 1alpha (MIP-1alpha), MIP-1beta, MIP-3alpha, regulated on activation, normal T expressed and secreted (RANTES), MIP-2, and interferon-inducible protein 10 (IP-10) mRNA expression was up-regulated between days 5 and 15 after infection, consistent with a role for these chemokines in leukocyte recruitment to the lung. Low levels of expression were detected for the CC chemokine receptors (CCR)2 and CCR5, whereas CXC chemokine receptor (CXCR)3 was significantly up-regulated by day 10 after infection, coinciding with peak inflammatory cell infiltration in the airways. As RANTES, IP-10, and their receptors were up-regulated during influenza virus infection, we investigated leukocyte recruitment and viral clearance in mice deficient in RANTES or CXCR3, the receptor for IP-10. Leukocyte recruitment and viral replication in influenza-infected RANTES knockout(-/-) mice were similar to that in control mice, showing that RANTES is not essential for the immune response to influenza infection. Similarly, leukocyte recruitment and viral replication in CXCR3-/- mice were identical to control mice, except at day 8 postinfection, where fewer lymphocytes, neutrophils, and eosinophils were detected in the bronchoalveolar lavage of CXCR3-/- mice. These studies suggest that although the chemokines detected may play a role in regulating leukocyte trafficking to the lung during influenza infection, some may be functionally redundant.

I-TAC/CXCL11 is a natural antagonist for CCR5.

The selective CXC chemokine receptor 3 (CXCR3) agonists, monokine induced by interferon-gamma (IFN- gamma)/CXC chemokine ligand 9 (CXCL9), IFN-inducible protein 10/CXCL10, and IFN-inducible T cell alpha chemoattractant (I-TAC)/CXCL11, attract CXCR3+ cells such as CD45RO+ T lymphocytes, B cells, and natural killer cells. Further, all three chemokines are potent, natural antagonists for chemokine receptor 3 (CCR3) and feature defensin-like, antimicrobial activities. In this study, we show that I-TAC, in addition to these effects, acts as an antagonist for CCR5. I-TAC inhibited the binding of macrophage-inflammatory protein-1alpha (MIP-1alpha)/CC chemokine ligand 3 (CCL3) to cells transfected with CCR5 and to monocytes. Furthermore, cell migration evoked by regulated on activation, normal T expressed and secreted (RANTES)/CCL5 and MIP-1beta/CCL4, the selective agonist of CCR5, was inhibited in transfected cells and monocytes, respectively. In two other functional assays, namely the release of free intracellular calcium and actin polymerization, I-TAC reduced CCR5 activities to minimal levels. Sequence and structure analyses indicate a potential role for K17, K49, and Q51 of I-TAC in CCR5 binding. Our results expand on the potential role of I-TAC as a negative modulator in leukocyte migration and activation, as I-TAC would specifically counteract the responses mediated by many "classical," inflammatory chemokines that act not only via CCR3 but via CCR5 as well.

Induction of RANTES by TWEAK/Fn14 Interaction in Human Keratinocytes

TNF-like weak inducer of apoptosis (TWEAK), a member of the tumor necrosis factor (TNF) family, is a multifunctional cytokine that regulate cellular proliferation, angiogenesis, inflammation, and apoptosis. In this study, we investigated the effect of TWEAK on human keratinocytes. Primary cultured normal human keratinocytes constitutively expressed a TWEAK receptor, fibroblast growth factor-inducible 14 (Fn14), and produced regulated on activation, normal T expressed and secreted (RANTES) upon TWEAK stimulation in a concentration-dependent manner. The TWEAK-induced RANTES production was abrogated by anti-Fn14 antibody, and synergistically augmented by simultaneous stimulation with transforming growth factor-beta. In addition, human keratinocytes differentiated in vitro with high Ca(2+)-containing medium showed enhanced production of RANTES upon TWEAK stimulation. Furthermore, TWEAK induced rapid phosphorylation of IkappaB-alpha in human keratinocytes. Collectively, TWEAK acts on human keratinocytes as an inducer of RANTES via Fn14. Because RANTES has been implicated in inflammation, TWEAK/Fn14 interaction in human keratinocytes may be involved in the pathophysiology of inflammatory skin disorders.

The effect of nasal polyp epithelial cells on eosinophil activation.

Eosinophil infiltration into an inflammatory site is a characteristic histological finding in patients with chronic rhinosinusitis and nasal polyps. Most of the eosinophils in chronic rhinosinusitis are activated in the nasal cavity, but the exact activation mechanism of eosinophils is unknown. The study was designed to investigate the effect of human nasal epithelial cells on the activation of eosinophils. Peripheral blood eosinophils were isolated from healthy volunteers and incubated in human nasal polyp epithelial cell conditioned media (HPECM). Superoxide production and eosinophil-derived neurotoxin were measured to determine eosinophils activation. HPECMs were assayed by ELISAs for interleukin-8 (IL-8), granulocyte-macrophage colony stimulating factor (GM-CSF), eotaxin, and regulated on activation normal T expressed and secreted (RANTES). To identify the chemical mediators involved in the activation of eosinophils. HPECM (n = 7) contained 31.48 ng/mL interleukin-8, 533.43 pg/mL GM-CSF, 5.90 pg/mL eotaxin, and 11.06 pg/mL RANTES. Eosinophils were activated by HPECM and inhibited only by anti-GM-CSF antibody, not by the other chemical mediators. The results suggest that eosinophils in nasal secretions are activated by GM-CSF, which is produced by nasal epithelial cells.

Functional expression of the eotaxin receptor CCR3 in CD30+ cutaneous T-cell lymphoma

Little is known about mechanisms involved in skin-specific homing of cutaneous T-cell lymphoma (CTCL). Chemokine/chemokine receptor interactions have been implicated in the homing of lymphoma cells to various tissue sites. We investigated tissue samples and tumor cell suspensions of patients with CD30(+) CTCL (n = 8) and CD30(-) CTCL (mycosis fungoides, n = 6; Sézary syndrome, n = 6) for expression of the chemokine receptors CCR3, CCR4, and CCR8 and the CCR3 ligands eotaxin/CCL11, monocyte chemoattractant protein 3 (MCP-3)/CCL7, and RANTES (regulated on activation, normal T expressed and secreted)/CCL5. Of 8 CD30(+) CTCLs, 7 expressed CCR3, 4 CCR4, and none CCR8. CCR3 expression was not found in skin tissue samples from 12 CD30(-) CTCLs. Coexpression of CCR3 and CD30 was demonstrated by flow cytometry in tumor cell suspensions. Internalization experiments demonstrated functionality of CCR3 expressed by freshly isolated tumor cells. Actin polymerization as well as migration in response to eotaxin was demonstrated in a CD30(+) cutaneous lymphoma cell line. CCR3 ligand eotaxin/CCL11 was detected in lesional skin of CD30(+) CTCL by immunohistochemistry, preferentially in tumor cells. Eotaxin/CCL11 expression in tumor cells was confirmed by intracellular immunofluorescence. Analysis of cytokine expression pattern of CCR3-bearing infiltrating cells showed a predominance of interleukin-4 (IL-4) but not interferon-gamma (IFN-gamma) protein expression,1 consistent with a T-helper 2 (Th-2) profile. These results suggest that expression of CCR3 and its ligand eotaxin/CCL11 plays a role in the recruitment and retention of CD30(+) malignant T cells to the skin.

Effect of FLT3-ligand treatment of BALF of ova sensitized and challenged mice

Hematopoietic progenitor cells are able to induce neovascularization of ischemic myocardium, inhibit apoptosis, and prevent heart failure. They express functional CC chemokine-binding receptor 3 (CCR3) and CXC chemokine-binding receptor 4 (CXCR4); however, the role of those receptors in migration of progenitor cells into the ischemic myocardium is unknown.Myocardial infarction was surgically induced in athymic nude rats, and human bone marrow–derived CD34+ cells or saline was injected into the tail vein. Cell chemotaxis was studied in vitro using chemotaxis chambers with or without concomitant stimulation with eotaxin or stromal cell–derived factor-1. Cell migration into ischemic myocardium was evaluated by immunohistochemistry. CCR3 and CXCR4 antibodies or local injections of stromal cell–derived factor-1 were used to investigate the role of chemokine expression in the migration capacity of the injected cells. Morphologic analysis included evaluation of apoptosis and capillary density in the ischemic myocardium.Ischemic rat myocardium demonstrated induced messenger RNA expression for the CCR3-binding chemokines eotaxin, RANTES (regulated on activation, normal T expressed and secreted), and monocyte chemotactic protein-3, but not the CXCR4-binding chemokine stromal cell–derived factor-1. Migration of human angioblasts to ischemic rat myocardium was inhibited by a blocking anti-CCR3 monoclonal antibody, but not by a blocking anti-CXCR4 monoclonal antibody, which instead inhibited migration to bone marrow. Finally, intramyocardial injection of stromal cell–derived factor-1 redirected migration of human angioblasts to ischemic rat hearts, resulting in augmented neovascularization, enhanced cardiomyocyte survival, and functional cardiac recovery.CCR3-dependent chemokine interactions regulate endogenous migration of CD34+ progenitors from bone marrow to ischemic but not to normal myocardium. Manipulating CXCR4-dependent interactions could enhance the efficacy of cell therapy after myocardial infarction.

Role of the autocrine chemokines MIP-1α and MIP-1β in the metastatic behavior of murine T cell lymphoma

The ESb-MP T-cell line is a highly malignant murine lymphoma, which preferentially metastasizes toward the kidney. This could be a result of the local production of monocyte chemoattractant protein-1 (MCP-1) and regulated on activation, normal T expressed and secreted (RANTES), which are chemotactic for ESb-MP cells. Here, we demonstrate that ESb-MP cells are already responsive to the chemotactic activity of macrophage inflammatory protein-1alpha (MIP-1alpha) and MIP-1beta from 1 ng/ml onward. Moreover, upon stimulation with lipopolysaccharide (LPS) or virus, ESb-MP cells themselves produce significant amounts of MIP-1 ( approximately 200 ng/ml). Indeed, the major autocrine chemoattractants, isolated from ESb-MP cells, were intact MIP-1alpha and MIP-1beta. Pretreatment with LPS or addition of MIP-1 inhibited the in vitro migration of ESb-MP cells toward various chemokines. Moreover, compared with untreated lymphoma cells, LPS-treated cells produced significantly less metastasis in mice. The results represented here suggest that the role of chemokines in attracting tumor cells at secondary sites depends on a balance between autocrine-produced and tissue-derived chemokines. This delicate balance should be considered in the design of antichemokine strategies in different tumor types.

The effect of RANTES on human sperm chemotaxis.

Follicular fluid (FF) is a powerful stimulator of human sperm hyperactivation and the acrosome reaction. FF causes sperm accumulation by way of chemotaxis. The chemoattractant in FF has not yet been identified in the human. It is well known that some types of chemokine such as RANTES (Regulated on Activation Normal T Expressed and Secreted Chemokine) exist in genital tract fluids (for example, FF, seminal plasma and uterine fluid). Few reports appear to exist concerning the direct effect of chemokines on the function of human sperm. The chemotactic effect of RANTES on human sperm were investigated by capillary and double-chamber assays, while the chemokinetic effect was investigated using computer-assisted sperm analysis. Both the capillary and double-chamber assays demonstrated a significant chemotactic effect of RANTES on human sperm. Anti-RANTES rabbit IgG partially neutralized the chemotactic effect of FF. In contrast, no statistically significant chemokinetic effect was observed in any motility parameter. Here, it was demonstrated that mRNA for the RANTES receptors CCR-1 and CCR-5 are present in human sperm. Furthermore, RANTES is involved in the chemotactic effect of FF in vitro.

Positive association between beta-chemokine-producing T cells and HIV type 1 viral load in HIV-infected subjects in Abidjan, Côte d'Ivoire.

The role of beta-chemokines in controlling HIV replication in vivo is still controversial. Therefore, the association between HIV-1 plasma viral load and the capacity of CD4(+) and CD8(+) T cells to produce beta-chemokines was studied in 28 antiretroviral drug-naïve HIV-1-infected female sex workers in Abidjan, Côte d'Ivoire. Percentages of beta-chemokine-positive T cells were measured in peripheral blood mononuclear cells by flow cytometry after intracellular staining for RANTES (regulated on activation, normal T expressed and secreted), macrophage inflammatory protein (MIP)-1alpha, and MIP-1beta. HIV-1-infected subjects had higher percentages of MIP-1alpha- and MIP-1beta-positive CD4(+) and CD8(+) T cells (p < 0.02) and of RANTES-positive CD8(+) T cells (p = 0.054) than uninfected controls. Percentages of RANTES- and MIP-1beta-positive CD8(+) T cells correlated directly with HIV-1 plasma viral load (p < 0.02). Percentages of beta-chemokine-positive CD4(+) and CD8(+) T cells correlated directly with percentages of HLA-DR-positive T cells (p < 0.02) and inversely (except RANTES in CD4(+) T cells) with absolute numbers of CD4(+) T cells (p < 0.05) in peripheral blood. These data indicate that increased percentages of beta-chemokine-producing T cells in HIV-1-infected subjects correlate with disease progression and are a sign of viremia-driven chronic T cell activation.

Elevated levels of beta-chemokines in bronchoalveolar lavage fluid (BALF) of individuals infected with human T lymphotropic virus type-1 (HTLV-1).

Pulmonary complications are known to develop in HTLV-1 carriers, including T lymphocytic alveolitis, and increased IL-2 receptor alpha (CD25)-bearing T cells have been found in BALF. Several chemokines may contribute to accumulation of T lymphocytes in the lungs of HTLV-1 carriers. Here, we compared the distribution of T lymphocyte subsets and beta-chemokines, such as macrophage inflammatory peptide-1alpha (MIP-1alpha), regulated on activation normal T expressed and secreted (RANTES), and macrophage chemoattractant protein-1 (MCP-1), in BALF and peripheral blood between HTLV-1 carriers and non-infected healthy normal subjects. Flow cytometric analysis with MoAbs to cell surface antigens was used to identify T lymphocyte subsets in BALF samples from HTLV-1 carriers (n = 13) and non-infected healthy controls (n = 10). The levels of different beta-chemokines were estimated by ELISA. High percentages of CD3+ cells, CD3 expressing HLA-DR antigen and CD3+CD25+ cells were detected in BALF of HTLV-1 carriers compared with non-infected controls. The concentration of MIP-1alpha in BALF of patients was significantly higher than in non-infected healthy controls and correlated well with the percentage of CD3+CD25+ cells. The level of RANTES in BALF was also significantly high in HTLV-1 carriers, but did not correlate with the percentage of CD3+CD25+ cells. On the other hand, the level of MCP-1 in BALF of HTLV-1 carriers was not different from that of controls. Our results suggest a possible interaction between activated T cells bearing CD25 and beta-chemokines, especially MIP-1alpha, which may contribute to the pulmonary involvement in HTLV-1 carriers.