Immunoenhancing property of dietary un-denatured whey protein derived from three camel breeds in mice

Data have demonstrated that whey protein (WP) enhances the immune system. The aim of this study was to investigate and compare the effects of WP from three camel breeds on oxidative stress, blood lipid profile and the cytokine levels. Seventy five male mice were randomly split into five groups. The first served as a control group. The second, the third and the fourth groups were orally administrated the WP from Majaheim, Maghateer and Soffer camel breeds, respectively, at a dose of 100 mg/kg mouse body weight. The fifth group was supplemented with bovine serum albumin (BSA). Results showed similar electrophoretic patterns of the three whey proteins. WP was found to significantly inhibit the hydroperoxide and the Reactive Oxygen Species (ROS) in leukocytes, liver and skin as well as the blood cholesterol level in a time dependent manner. A significant enhancement of glutathione was revealed in WP groups. Furthermore, WP was found to significantly elevate the IL-2 with a significant time dependent enhance of IL-8. On contrast, a significant lowering effect of whey proteins on the pro-inflammatory cytokines, IL-1α, IL-1β, IL-6 and IL-10 was detected. Moreover, a mitogenic activity of WP was observed on the lymphocytes. Non-significant changes were observed in AST, ALT, creatinine and glucose level. These findings suggest that WP significantly improved the levels of the oxidative markers and the immune functions without any difference in the bioactivities of the three studied whey proteins.     

Supplementation with undenatured whey protein during diabetes mellitus improves the healing and closure of diabetic wounds through the rescue of functional long-lived wound macrophages

Long and persistent uncontrolled diabetes tends to degenerate the immune system and increase the incidence of infections in diabetic patients. A serious complication of diabetes is impaired healing, which diminishes physical activity and, in some cases, leads to chronic wounds and limb amputation. Whey proteins (WPs) enhance immunity during early development and have a protective role in some immune disorders. The effect of camel WPs on wound healing in a streptozotocin-induced type 1 diabetic mice model was investigated. Sixty male mice were equally distributed into 3 experimental groups: group 1, non-diabetic control mice; group 2, diabetic mice; and group 3, diabetic mice that were orally supplemented with undenatured WP (100 mg/kg body weight/day for 1 month through oral gavage). We observed that the diabetic mice exhibited delayed wound closure characterized by a significant reduction in collagen deposition, prolonged elevation in inflammatory cytokines, aberrant activation of STAT3 and reduction in the activation of Akt and NF-κB when compared with the control mice. Moreover, in the diabetic mice, the wound-resident macrophages were dysfunctional and demonstrated increased apoptosis, a significant reduction in their phagocytotic ability, aberrant activation of STAT3 and a marked reduction in the activation of Akt. Interestingly, the supplementation of diabetic mice with WP significantly enhanced the collagen deposition, limited the inflammatory stimuli, restored the activation of STAT3, Akt and NF-κB and greatly improved the closure of diabetic wounds compared with the control mice. Most important, the supplementation of diabetic mice with WP rescued functional, long-lived wound-resident macrophages. Our data reveal the benefits of WP supplementation in improving the healing and closure of diabetic wounds.     

Critical role for CXC chemokine ligand 16 (SR-PSOX) in Th1 response mediated by NKT cells

The transmembrane chemokine CXCL 16 (CXCL16), which is the same molecule as the scavenger receptor that binds phosphatidylserine and oxidized lipoprotein (SR-PSOX), has been shown to mediate chemotaxis and adhesion of CXC chemokine receptor 6-expressing cells such as NKT and activated Th1 cells. We generated SR-PSOX/CXCL16-deficient mice and examined the role of this chemokine in vivo. The mutant mice showed a reduced number of liver NKT cells, and decreased production of IFN-gamma and IL-4 by administration of alpha-galactosylceramide (alphaGalCer). Of note, the alphaGalCer-induced production of IFN-gamma was more severely impaired than the production of IL-4 in SR-PSOX-deficient mice. In this context, SR-PSOX-deficient mice showed impaired sensitivity to alphaGalCer-induced anti-tumor effect mediated by IFN-gamma from NKT cells. NKT cells from wild-type mice showed impaired production of IFN-gamma, but not IL-4, after their culture with alphaGalCer and APCs from mutant mice. Moreover, Propionibacterium acnes-induced in vivo Th1 responses were severely impaired in SR-PSOX-deficient as well as NKT KO mice. Taken together, SR-PSOX/CXCL16 plays an important role in not only the production of IFN-gamma by NKT cells, but also promotion of Th1-inclined immune responses mediated by NKT cells.     

Suppressor of cytokine signalling (SOCS) 1 and 3 enhance cell adhesion and inhibit migration towards the chemokine eotaxin/CCL11

Suppressors of cytokine signalling (SOCS) proteins regulate signal transduction, but their role in responses to chemokines remains poorly understood. We report that cells expressing SOCS1 and 3 exhibit enhanced adhesion and reduced migration towards the chemokine CCL11. Focal adhesion kinase (FAK) and the GTPase RhoA, control cell adhesion and migration and we show the presence of SOCS1 or 3 regulates expression and tyrosine phosphorylation of FAK, while also enhancing activation of RhoA. Our novel findings suggest that SOCS1 and 3 may control chemotaxis and adhesion by significantly enhancing both FAK and RhoA activity, thus localizing immune cells to the site of allergic inflammation.     

Antagonist of secondary lymphoid-tissue chemokine (CCR ligand 21) prevents the development of chronic graft-versus-host disease in mice

The use of receptor antagonists for chemokines is an alternative approach to blocking chemokine actions and has the potential to provide novel therapeutics. We determined the receptor antagonist properties of murine N-terminally truncated secondary lymphoid tissue chemokine (SLC)/6Ckine/CCR ligand 21 analogs and evaluated the preventive effects of SLC antagonists on chronic graft-vs-host disease (GVHD) in a murine model by blocking the homing of donor CCR7-expressing T cells into the recipient's lymphoid organs. SLC analogs truncated >4 aa residues from the N terminus showed a loss of chemotaxis and Ca2+ influx of CCR7-expressing cells and also inhibited SLC-stimulated chemotaxis and SLC-induced Ca2+ influx completely. To determine whether SLC antagonist inhibits the development of chronic GVHD, chronic GVHD was induced by injecting DBA/2 spleen cells into (C57BL/6 x DBA/2) F1 mice. Total numbers of spleen cells and host B cells, serum levels of IgE, and of total IgG and IgG1 of anti-DNA Abs in SLC antagonist-treated GVHD mice were significantly lower than those in control PBS-treated GVHD mice. This was due to a reduction in the levels of activated donor CD4+ T cells and a decrease in IL-4 production, resulting in a reduction in the numbers of activated host B cells. Therefore, our results suggest that SLC antagonist has beneficial effects for the prevention of chronic GVHD.     

Pulmonary immune cells and inflammatory cytokine dysregulation are associated with mortality of IL-1R1-/-mice infected with influenza virus (H1 N1)

Respirovirus infection can cause viral pneumonia and acute lung injury (ALI).The interleukin-1 (IL-1) family consists of proinflammatory cytokines that play essential roles in regulating immune and inflammatory responses in vivo.IL-1 signaling is associated with protection against respiratory influenza virus infection by mediation of the pulmonary anti-viral immune response and inflammation.We analyzed the infiltration lung immune leukocytes and cytokines that contribute to inflammatory lung pathology and mortality of fatal H1N1 virus-infected IL-1 receptor 1 (IL-1R1) deficient mice.Results showed that early innate immune cells and cytokine/chemokine dysregulation were observed with significantly decreased neutrophil infiltration and IL-6,TNF-α,G-CSF,KC,and MIP-2 cytokine levels in the bronchoalveolar lavage fluid of infected IL-1R1-/-mice in comparison with that of wild type infected mice.The adaptive immune response against the H1N1 virus in IL-1R1-/-mice was impaired with downregulated anti-viral Th1 cell,CD8+ cell,and antibody functions,which contributes to attenuated viral clearance.Histological analysis revealed reduced lung inflammation during early infection but severe lung pathology in late infection in IL-1R1-/-mice compared with that in WT infected mice.Moreover,the infected IL-1R1-/-mice showed markedly reduced neutrophil generation in bone marrow and neutrophil recruitment to the inflamed lung.Together,these results suggest that IL-1 signaling is associated with pulmonary anti-influenza immune response and inflammatory lung injury,particularly via the influence on neutrophil mobilization and inflammatory cytokine/chemokine production.     

CC chemokine receptor 1 enhances susceptibility to Leishmania major during early phase of infection

CC chemokine receptor 1 (CCR1) is expressed on the surfaces of monocytes, lymphocytes, neutrophils and eosinophils. CC chemokine receptor 1 not only regulates leucocyte chemotaxis, but also plays a role in the regulation of Th1/Th2 cytokine responses. To determine the role of CCR1 in regulation of immune response during Leishmania major infection, we analysed the course of cutaneous L. major infection in CCR1-deficient C57BL/6 mice (CCR1-/-) and compared with similarly infected wild-type mice (CCR1+/+). Following L. major infection, CCR1-/- mice developed significantly smaller lesions containing fewer parasites than CCR1+/+ mice. Furthermore, the severity of the inflammation as assessed by the degree of leucocyte infiltration at the site of infection was similar in CCR1+/+ and CCR1-/- mice. Although both groups developed significant antibody responses following L. major infection, CCR1-/- mice produced significantly lower IgE. On day 20 postinfection, LmAg-stimulated lymph node cells from L. major-infected CCR1+/+ and CCR1-/- mice produced comparable levels of IL-12 and IFN-gamma, but those from CCR1-/- mice produced significantly less IL-4 and IL-10. By day 70, lymph node cells from both CCR1+/+ and CCR1-/- mice produced significant amounts of IL-12 and IFN-gamma but low IL-4. At both time points, the draining lymph nodes from CCR1+/+ and CCR1-/- mice contained similar number of leucocytes. These results demonstrate that CCR1 plays a role in pathogenesis of cutaneous L. major infection. Moreover, they also indicate that CCR1 exacerbates L. major infection in C57BL/6 mice by up-regulating Th2-like response rather than inhibiting Th1 development or/and influencing leucocyte chemotaxis.     

Cytokine and chemokine responses in patients co-infected with Entamoeba histolytica/dispar, Necator americanus and Mansonella perstans and changes after anti-parasite treatment

This study examined the impact of concurrent parasite infections (amoebiasis, filariasis, necatoriasis) and the effect of anti-parasite treatment on cytokine and chemokine responses in singly and poly-parasitized patients. Cellular reactivity and parasite-specific Th1- and Th2-type cytokine and chemokine profiles were investigated before and six weeks after treatment. In those patients infected with three parasite species, cellular secretion of interleukin 5 (IL-5) and IL-12p40 by PBMC was strongly diminished (p<0.005) but IL-10 was elevated in parasite-infected patients (p<0.0001) in response to protozoa- and helminth-specific as well as bacteria-specific antigens. Macrophage inflammatory chemokines (MIP-1alpha/CCL3 and MIP-1beta/CCL4), macrophage-derived chemokine (MDC/CCL22) and neutrophil activating chemokine (IL-8/CXCL8) were produced by PBMC in similar amounts in endemic controls and singly and poly-parasitized patients, but thymus and activation-regulated chemokine (TARC/CCL17) was produced the highest by PBMC from patients with triple parasite infections (p<0.0001). Following anti-parasite therapy, secretion of IL-12p40 and IL-5 augmented significantly in treated patients while IL-10, MDC, MIP-1alpha, TARC and IL-8 substantially diminished (all p<10(-5)) when their PBMC were activated with parasite- and bacteria-specific antigens. In summary, PBMC from poly-parasitized patients responded to protozoa- and helminth-specific antigens with a compromised IL-5 and IL-12p40 but high IL-10 and a substantial chemokine release. Chemokines may attract and activate effector cells in peri-parasitic tissues to limit parasite proliferation and dissemination, while depressed IL-5 and IL-12p40 but prominent IL-10 may prevent eosinophil and cytotoxic cell-mediated inflammatory processes and pathogenesis to the host. The changes in this profile following anti-parasite therapy disclosed the dynamics of an immune adaptation associated with parasite accumulation and also with clearance of parasite infections.     

The expression of the cytomegalovirus chemokine receptor homolog US28 sequesters biologically active CC chemokines and alters IL-8 production

We hypothesized that US28, a cytomegalovirus (CMV) CC chemokine receptor homolog, plays a role in modulating the host antiviral defense. Monocyte chemotaxis was induced by supernatants from fibroblasts infected with a US28 deletion mutant of CMV (CMV Delta US28) due to endogenously produced CC chemokines MCP-1 and RANTES. However, these chemokines were sequestered from the supernatants of CMV-infected cells that did express US28. US28 was also capable of sequestering exogenously added RANTES. Surprisingly, cells infected with CMV Delta US28 transcribed and secreted increased levels IL-8, a CXC chemokine, when compared to CMV-infected cells. Finally, because chemokines are potent mediators of immune cell migration through the endothelium, we characterized the CC chemokine binding potential of CMV-infected endothelial cells. We propose that US28 functions as a 'chemokine sink' by sequestering endogenously and exogenously produced chemokines and alters the production of the CXC chemokine IL-8, suggesting that CMV could significantly alter the inflammatory milieu surrounding infected cells.     

Effects of exercise training on plasma cytokine and chemokine levels, and thermoregulation

Pyrogenic factors may include the proinflammatory cytokines such as interleukin (IL)-1β, IL-6, tumor necrosis factor-alpha (TNF-α), and IL-8 (chemokine). Exercise also causes cytokinemia that might result in pyrogenically mediated body temperature elevation. The aim of the present study was to determine the effect of exercise training on exercise-induced plasma concentrations of IL-1β, IL-6, TNF-α, and IL-8. Messenger RNA levels of these factors were also evaluated in peripheral blood leukocytes. We also observed the relationship between cykokines, chemokines, and sweating after exercise. Nine tennis athletes (n=9) and untrained sedentary control subjects (n=10) ran for 1 h at 75% intensity of VO_2max. Venous blood samples were analyzed for plasma concentrations and mRNA expression in leukocytes of cytokines and chemokine of interest. Sweat volume was calculated by measuring body weight changes. Leukocyte mRNA expression and plasma protein levels of IL-1β, IL-6, TNF-α, and IL-8 immediately increased after exercise in both groups, but to a much greater extent in the athletic group. However, mRNA expression and plasma protein level for IL-6 and TNF-α, unlike IL-1β and IL-8, decreased more quickly in the athletic group compared to the control group during the recovery period. Compared to the control group, greater sweat loss volumes, and lower body temperatures in athletic group were observed at all time points. In conclusion, exercise training improved physical capacity and sweating function so that body temperature was more easily regulated during and after exercise. This may due to improved production of specific cytokine and chemokine in sweating during exercise.     

趋化因子CXCL12及其受体CXCR4在胶质瘤中的研究进展

CXCL12是趋化因子家族成员之一,是能够特异性结合其受体CXCR4发挥趋化性作用的细胞因子。最初,CXCL12及CXCR4被发现于炎症细胞,参与机体炎症、免疫等病理反应。接下来的几年中发现,它在机体发育、成熟过程中也有重要作用。如今,大量研究表明它与肿瘤的生长、侵袭及转移密切相关。据报道,在乳腺癌、肺癌、卵巢癌等二十余种肿瘤组织中发现CXCL12及CXCR4的表达,其中也包括中枢系统肿瘤-胶质瘤。CXCL12/CXCR4参与胶质瘤生长过程的多个步骤,包括肿瘤增殖、侵袭、转移等。有实验指出,转移灶的CXCR4表达水平较原发灶高,CXCR4有可能成为抑制胶质瘤生长、转移的重要靶目标。     

Chemokines and chemokine receptors in infectious diseases

Today, 10 years after the discovery of IL-8, chemokines (chemotactic cytokines) are seen as the stimuli that largely control leucocyte migration. Chemokines are low molecular weight chemoattractant cytokines secreted by a variety of cells, including leucocytes, epithelial cells, endothelial cells, fibroblasts and numerous other cell types. They are produced in response to exogenous stimuli, such as viruses and bacterial LPS, and endogenous stimuli, such as IL-1, TNF and IFN. These factors mediate chemotaxis and leucocyte activation. They also regulate leucocyte extravasation from the blood and/or lymph vessel luminal surface to the tissue space, the site of inflammation. There is no doubt that chemokines and chemokine receptors are critical for defence against infectious pathogens. It is also clear that these pathogens have evolved to accommodate the workings of the host immune system. Survival of these infectious agents appears dependent upon strategies that can evade, suppress, counteract or otherwise confound the constellation of host responses to invading pathogens. In this regard, the chemokines and their receptors are a major target. Reviewed in the present paper are several examples in which microbial pathogens have usurped the mammalian chemokine system to subvert the host immune response.     

Early divergent host responses in SHIVsf162P3 and SIVmac251 infected macaques correlate with control of viremia

We previously showed intravaginal inoculation with SHIVsf162p3 results in transient viremia followed by undetectable viremia in most macaques, and some displayed subsequent immunity to superinfection with pathogenic SIVmac251. Here we compare early T cell activation, proliferation, and plasma cytokine/chemokine responses in macaques intravaginally infected with either SHIVsf162p3 or SIVmac251 to determine whether distinct differences in host responses may be associated with early viral containment. The data show SIVmac251 infection results in significantly higher levels of T cell activation, proliferation, and a mixed cytokine/chemokine "storm" in plasma in primary infection, whereas infection with SHIVsf162p3 resulted in significantly lower levels of T cell activation, proliferation, and better preservation of memory CD4+ T cells in early infection which immediately preceded control of viremia. These results support the hypothesis that early systemic immune activation, T cell proliferation, and a more prominent and broader array of cytokine/chemokine responses facilitate SIV replication, and may play a key role in persistence of infection, and the progression to AIDS. In contrast, immune unresponsiveness may be associated with eventual clearance of virus, a concept that may have key significance for therapy and vaccine design.     

Activating and inhibitory Ly49 receptors modulate NK cell chemotaxis to CXC chemokine ligand (CXCL) 10 and CXCL12

NK cells can migrate into sites of inflammatory responses or malignancies in response to chemokines. Target killing by rodent NK cells is restricted by opposing signals from inhibitory and activating Ly49 receptors. The rat NK leukemic cell line RNK16 constitutively expresses functional receptors for the inflammatory chemokine CXC chemokine ligand (CXCL)10 (CXCR3) and the homeostatic chemokine CXCL12 (CXCR4). RNK-16 cells transfected with either the activating Ly49D receptor or the inhibitory Ly49A receptor were used to examine the effects of NK receptor ligation on CXCL10- and CXCL12-mediated chemotaxis. Ligation of Ly49A, either with Abs or its MHC class I ligand H2-D(d), led to a decrease in chemotactic responses to either CXCL10 or CXCL12. In contrast, Ly49D ligation with Abs or H2-D(d) led to an increase in migration toward CXCL10, but a decrease in chemotaxis toward CXCL12. Ly49-dependent effects on RNK-16 chemotaxis were not the result of surface modulation of CXCR3 or CXCR4 as demonstrated by flow cytometry. A mutation of the Src homology phosphatase-1 binding motif in Ly49A completely abrogated Ly49-dependent effects on both CXCL10 and CXCL12 chemotaxis, suggesting a role for Src homology phosphatase-1 in Ly49A/chemokine receptor cross-talk. Ly49D-transfected cells were pretreated with the Syk kinase inhibitor Piceatannol before ligation, which abrogated the previously observed changes in migration toward CXCL10 and CXCL12. Piceatannol also abrogated Ly49A-dependent inhibition of chemotaxis toward CXCL10, but not CXCL12. Collectively, these data suggest that Ly49 receptors can influence NK cell chemotaxis within sites of inflammation or tumor growth upon interaction with target cells.     

The role of MAPK in Kupffer cell toll-like receptor (TLR) 2-, TLR4-, and TLR9-mediated signaling following trauma-hemorrhage

Severe injury deranges immune function and increases the risk of sepsis and multiple organ failure. Kupffer cells play a major role in mediating posttraumatic immune responses, in part via different Toll-like receptors (TLR). Although mitogen-activated protein kinases (MAPK) are key elements in the TLR signaling pathway, it remains unclear whether the activation of different MAPK are TLR specific. Male C3H/HeN mice underwent midline laparotomy (i.e., soft tissue injury), hemorrhagic shock (MAP approximately 35 mm Hg for 90 min), and resuscitation. Kupffer cells were isolated 2 h thereafter, lysed and immunoblotted with antibodies to p38, ERK1/2, or JNK proteins. In addition, cells were preincubated with specific inhibitors of p38, ERK1/2, or JNK MAPK followed by stimulation with the TLR2 agonist, zymosan; the TLR4 agonist, LPS; or the TLR9 agonist, CpG DNA. Cytokine (TNF-alpha, interleukin-6 (IL-6), monocyte chemoattractant protein-1 (MCP-1), and KC) production was determined by cytometric bead array after 24 h in culture. MAPK activity as well as TNF-alpha, MCP-1, and KC production by Kupffer cells were significantly increased following trauma-hemorrhage. TLR4 activation by LPS stimulation increased the levels of all measured cytokines. CpG-stimulated TLR9 signaling increased TNF-alpha and IL-6 levels; however, it had no effect on chemokine production. Selective MAPK inhibition demonstrated that chemokine production was mediated via p38 and JNK MAPK activation in TLR2, -4, and -9 signaling. In contrast, TNF-alpha and IL-6 production was differentially regulated by MAPK depending on the TLR pathway stimulated. Thus, Kupffer cell TLR signaling employs different MAPK pathways in eliciting cytokine and chemokine responses following trauma-hemorrhage.     

Nitric oxide regulation of human peripheral blood mononuclear cells: critical time dependence and selectivity for cytokine versus chemokine expression

NO is antiproliferative for T cells and other immune cells, but there is debate over whether it influences cytokine expression and if so whether it shows cytokine selectivity. Furthermore, the NO effect may depend on exposure time. To address these issues, we precultured human PBMC with the NO donors S-nitrosoglutathione (a natural storage form of NO) or S-nitroso-N-acetyl-D-penicillamine for up to 48 h before cell activation and then monitored proliferation and cytokine and chemokine expression. S-nitrosoglutathione or S-nitroso-N-acetyl-D-penicillamine, but not their non-NO-releasing analogues, inhibited proliferation induced by PHA or IL-2, the effect declining progressively from 48 to 0 h pre-exposure to the mitogen. This was accompanied by reduced PHA-induced IL-2 release and reduced IL-2, IFN-gamma, and IL-13 mRNA expression. In contrast, NO did not influence PHA-induced expression of mRNA for the chemokines lymphotactin, RANTES, IFN-gamma-inducible protein, macrophage-inhibitory protein-1alpha, macrophage-inhibitory protein-1beta, macrophage chemoattractant protein-1, and IL-8 or release of RANTES or IL-8. The NO effects were not toxic and were not accompanied by changes in PHA-induced CD25 expression. We conclude that exposure time to NO is critical to altered PBMC responsiveness and that NO inhibits expression of both Th1 and Th2 cytokines but not chemokines.     

CC chemokine ligand 5/RANTES chemokine antagonists aggravate glomerulonephritis despite reduction of glomerular leukocyte infiltration

The chemokine CC chemokine ligand (CCL)5/RANTES as well as its respective receptor CCR5 mediate leukocyte infiltration during inflammation and are up-regulated early during the course of glomerulonephritis (GN). We tested the effects of the two CCL5/RANTES blocking analogs, Met-RANTES and amino-oxypentane-RANTES, on the course of horse apoferritin (HAF)-induced GN. HAF-injected control mice had proliferative GN with mesangial immune complex deposits of IgG and HAF. Daily i.p. injections of Met-RANTES or amino-oxypentane-RANTES markedly reduced glomerular cell proliferation and glomerular macrophage infiltration, which is usually associated with less glomerular injury and proteinuria in HAF-GN. Surprisingly, however, HAF-GN mice treated with both analogs showed worse disease with mesangiolysis, capillary obstruction, and nephrotic range albuminuria. These findings were associated with an enhancing effect of the CCL5/RANTES analogs on the macrophage activation state, characterized by a distinct morphology and increased inducible NO synthetase expression in vitro and in vivo, but a reduced uptake of apoptotic cells in vivo. The humoral response and the Th1/Th2 balance in HAF-GN and mesangial cell proliferation in vitro were not affected by the CCL5/RANTES analogs. We conclude that, despite blocking local leukocyte recruitment, chemokine analogs can aggravate some specific disease models, most likely due to interactions with systemic immune reactions, including the removal of apoptotic cells and inducible NO synthetase expression.