Low-dose interleukin-2 promotes STAT-5 phosphorylation, Treg survival and CTLA-4-dependent function in autoimmune liver diseases.

CD4+ CD25high CD127low forkhead box protein 3 (FoxP3+ ) regulatory T cells (Treg ) are essential for the maintenance of peripheral tolerance. Impaired Treg function and an imbalance between effector and Tregs contribute to the pathogenesis of autoimmune diseases. We reported recently that the hepatic microenvironment is deficient in interleukin (IL)-2, a cytokine essential for Treg survival and function. Consequently, few liver-infiltrating Treg demonstrate signal transducer and activator of transcription-5 (STAT-5) phosphorylation. To establish the potential of IL-2 to enhance Treg therapy, we investigated the effects of very low dose Proleukin (VLDP) on the phosphorylation of STAT-5 and the subsequent survival and function of Treg and T effector cells from the blood and livers of patients with autoimmune liver diseases. VLDP, at less than 5 IU/ml, resulted in selective phosphorylation of STAT-5 in Treg but not effector T cells or natural killer cells and associated with increased expression of cytotoxic T lymphocyte antigen-4 (CTLA-4), FoxP3 and CD25 and the anti-apoptotic protein Bcl-2 in Treg with the greatest enhancement of regulatory phenotype in the effector memory Treg population. VLDP also maintained expression of the liver-homing chemokine receptor CXCR3. VLDP enhanced Treg function in a CTLA-4-dependent manner. These findings open new avenues for future VLDP cytokine therapy alone or in combination with clinical grade Treg in autoimmune liver diseases, as VLDP could not only enhance regulatory phenotype and functional property but also the survival of intrahepatic Treg .

Flightless I is a key regulator of the fibroproliferative process in hypertrophic scarring and a target for a novel antiscarring therapy.

BACKGROUND: Hypertrophic scarring carries a large burden of disease, including disfigurement, pain and disability. There is currently no effective medical treatment to reduce or prevent hypertrophic scarring. Flightless I (Flii), a member of the gelsolin family of actin remodelling proteins, is an important negative regulator of wound repair. OBJECTIVES: The objective of this study was to investigate the role of Flii as a potential regulator of hypertrophic scarring. METHODS: Using human skin samples and an animal model of bleomycin-induced hypertrophic scarring in mice that overexpress or have reduced expression of Flii, we investigated its effect on dermal fibrosis and hypertrophic scarring. RESULTS: Flii expression was increased in human burns and hypertrophic scars. A similar increase in Flii was observed in hypertrophic scars formed in mice post-treatment with bleomycin. However, Flii-deficient (Flii(+/-) ) mice had reduced scarring in response to bleomycin evidenced by decreased dermal thickness, smaller cross-sectional scar areas, fewer myofibroblasts and a decreased collagen I/III ratio. In contrast, bleomycin-treated Flii-overexpressing mice (Flii(Tg/Tg) ) showed increased scar dermal thickness, larger cross-sectional scar areas, more myofibroblasts and an increased collagen I/III ratio. Injecting developing scars with a Flii neutralizing antibody led to a significant reduction in the size of the scars and a reduction in the collagen I/III ratio. CONCLUSIONS: This study identifies Flii as a profibrotic agent that contributes to excessive scar formation. Reducing its activity using neutralizing antibodies is a promising approach for reducing hypertrophic scarring.

Osteopontin neutralisation abrogates the liver progenitor cell response and fibrogenesis in mice.

BACKGROUND: Chronic liver injury triggers a progenitor cell repair response, and liver fibrosis occurs when repair becomes deregulated. Previously, we reported that reactivation of the hedgehog pathway promotes fibrogenic liver repair. Osteopontin (OPN) is a hedgehog-target, and a cytokine that is highly upregulated in fibrotic tissues, and regulates stem-cell fate. Thus, we hypothesised that OPN may modulate liver progenitor cell response, and thereby, modulate fibrotic outcomes. We further evaluated the impact of OPN-neutralisation on murine liver fibrosis. METHODS: Liver progenitors (603B and bipotential mouse oval liver) were treated with OPN-neutralising aptamers in the presence or absence of transforming growth factor (TGF)-ß, to determine if (and how) OPN modulates liver progenitor function. Effects of OPN-neutralisation (using OPN-aptamers or OPN-neutralising antibodies) on liver progenitor cell response and fibrogenesis were assessed in three models of liver fibrosis (carbon tetrachloride, methionine-choline deficient diet, 3,5,-diethoxycarbonyl-1,4-dihydrocollidine diet) by quantitative real time (qRT) PCR, Sirius-Red staining, hydroxyproline assay, and semiquantitative double-immunohistochemistry. Finally, OPN expression and liver progenitor response were corroborated in liver tissues obtained from patients with chronic liver disease. RESULTS: OPN is overexpressed by liver progenitors in humans and mice. In cultured progenitors, OPN enhances viability and wound healing by modulating TGF-ß signalling. In vivo, OPN-neutralisation attenuates the liver progenitor cell response, reverses epithelial-mesenchymal-transition in Sox9+ cells, and abrogates liver fibrogenesis. CONCLUSIONS: OPN upregulation during liver injury is a conserved repair response, and influences liver progenitor cell function. OPN-neutralisation abrogates the liver progenitor cell response and fibrogenesis in mouse models of liver fibrosis.

The effects of CCR5 inhibition on regulatory T-cell recruitment to colorectal cancer.

BACKGROUND: Regulatory T cells (Treg) are enriched in human colorectal cancer (CRC) where they suppress anti-tumour immunity. The chemokine receptor CCR5 has been implicated in the recruitment of Treg from blood into CRC and tumour growth is delayed in CCR5-/- mice, associated with reduced tumour Treg infiltration. METHODS: Tissue and blood samples were obtained from patients undergoing resection of CRC. Tumour-infiltrating lymphocytes were phenotyped for chemokine receptors using flow cytometry. The presence of tissue chemokines was assessed. Standard chemotaxis and suppression assays were performed and the effects of CCR5 blockade were tested in murine tumour models. RESULTS: Functional CCR5 was highly expressed by human CRC infiltrating Treg and CCR5(high) Treg were more suppressive than their CCR5(low) Treg counterparts. Human CRC-Treg were more proliferative and activated than other T cells suggesting that local proliferation could provide an alternative explanation for the observed tumour Treg enrichment. Pharmacological inhibition of CCR5 failed to reduce tumour Treg infiltration in murine tumour models although it did result in delayed tumour growth. CONCLUSIONS: CCR5 inhibition does not mediate anti-tumour effects as a consequence of inhibiting Treg recruitment. Other mechanisms must be found to explain this effect. This has important implications for anti-CCR5 therapy in CRC.

Pediatric Liver Transplant Recipients Who Undergo Transfer to the Adult Healthcare Service Have Good Long-Term Outcomes.

Liver transplantation has transformed survival for children with liver disease necessitating the transfer of a growing number of patients to the adult healthcare service. The impact of transfer on outcomes remains unclear. The aim of this single-center study of 137 consecutive pediatric liver transplant recipients was to examine the effect of transfer on patient and graft survival. The median time from transplant to transfer was 10.4 years and the median age of the patients at transfer was 18.6 years. After transfer, there were 5 re-transplants and 12 deaths in 14 patients. The estimated posttransfer 10-year patient and graft survival was 89.9% and 86.2%, respectively. Overall, 4 patients demonstrated graft loss as a consequence of chronic rejection. Graft loss was associated with older age at first transplant (p = 0.008). When compared to young adult patients transplanted in the adult center, the transferred patients did not have inferior graft survival from the point of transfer (HR 0.28; 95% CI 0.10-0.77, p = 0.014). This suggests that transfer did not impact significantly on graft longevity. In conclusion, pediatric liver transplant recipients who undergo transfer to the adult service have good long-term outcomes.

Mortality due to a retained circle hook in a longfin mako shark Isurus paucus (Guitart-Manday).

A female longfin mako shark Isurus paucus (Guitart-Manday, 1966) was found moribund on the Atlantic Ocean beach near Canaveral National Seashore, Florida; the shark died shortly after stranding. Macroscopic lesions included a partially healed bite mark on the left pectoral fin, a clefted snout, pericardial effusion and a pericardial mass surrounding a 12/0 circle fishing hook. The heart, pericardial mass, gills, ovary, oviduct, shell gland, epigonal organ, liver, kidney and intrarenal and interrenal glands were processed for histopathology and examined by brightfield microscopy. Microscopic examination revealed chronic proliferative and pyogranulomatous pericarditis and myocarditis with rhabdomyolysis, fibrosis and thrombosis; scant bacteria and multifocal granular deposits of iron were found intralesionally. In addition, acute, multifocal infarcts within the epigonal organ and gill filaments were found in association with emboli formed by necrocellular material. The ovary had high numbers of atretic follicles, and the liver had diffuse, severe hepatocellular degeneration, multifocal spongiosis and moderate numbers of melanomacrophage cells. This report provides evidence of direct mortality due to systemic lesions associated with retained fishing gear in a prohibited shark species. Due to the large numbers of sharks released from both recreational and commercial fisheries worldwide, impact of delayed post-release mortality on shark populations is an important consideration.

Validated age, growth and maturity of the bonnethead Sphyrna tiburo in the western North Atlantic Ocean.

The age, growth and maturity of bonnetheads Sphyrna tiburo inhabiting the estuarine and coastal waters of the western North Atlantic Ocean (WNA) from Onslow Bay, North Carolina, south to West Palm Beach, Florida, were examined. Vertebrae were collected and aged from 329 females and 217 males ranging in size from 262 to 1043 mm and 245 to 825 mm fork length, LF , respectively. Sex-specific von Bertalanffy growth curves were fitted to length-at-age data. Female von Bertalanffy parameters were L∞ = 1036 mm LF , k = 0·18, t0 = -1·64 and L0 = 272 mm LF . Males reached a smaller theoretical asymptotic length and had a higher growth coefficient (L∞ = 782 mm LF , k = 0·29, t0 = -1·43 and L0 = 266 mm LF ). Maximum observed age was 17·9 years for females and 16·0 years for males. Annual deposition of growth increments was verified by marginal increment analysis and validated for age classes 2·5+ to 10·5+ years through recapture of 13 oxytetracycline-injected specimens at liberty in the wild for 1-4 years. Length (LF50 ) and age (A50 ) at 50% maturity were 819 mm and 6·7 years for females, and 618 mm and 3·9 years for males. Both female and male S. tiburo in the WNA had a significantly higher maximum observed age, LF50 , A50 and L∞ , and a significantly lower k and estimated L0 than evident in the Gulf of Mexico (GOM). These significant differences in life-history parameters, as well as evidence from tagging and genetic studies, suggest that S. tiburo in the WNA and GOM should be considered separate stocks.

Soluble urokinase plasminogen activator receptor is compartmentally regulated in decompensated cirrhosis and indicates immune activation and short-term mortality.

OBJECTIVE: Patients with decompensated cirrhosis are susceptible to bacterial infections, which are associated with organ failure and a high mortality rate. Reliable biomarkers are needed to identify patients who require intensified treatment. Our objective was to study the regulation and prognostic relevance of elevated concentrations of soluble urokinase plasminogen activator receptor (suPAR) in patients with advanced cirrhosis. DESIGN, SETTING AND PARTICIPANTS: We examined the associations between serum and ascitic fluid (AF) suPAR and liver function, bacterial infection, and short-term mortality in 162 consecutive patients with decompensated cirrhosis undergoing diagnostic paracentesis in a tertiary health care centre in Germany. MAIN OUTCOME MEASURE: Twenty-eight-day mortality. RESULTS: Circulating suPAR levels were increased in patients with decompensated cirrhosis and correlated with the severity of liver dysfunction and systemic inflammation but were not indicative of bacterial infection. Circulating suPAR levels >14.4 ng mL(-1) predicted 28-day mortality, even after adjustment for liver function and confounders [HR = 3.05 (1.35-6.90); P = 0.0076] equal to the MELD score (AUC = 0.71; 95% CI = 0.61-0.81; P < 0.001). Cut-off levels derived from cohorts without liver disease were not applicable due to the low specificity. AF suPAR levels were elevated during spontaneous bacterial peritonitis (SBP), but not during episodes in which bacteria or bacterial DNA was translocated into the ascites. AF suPAR levels correlated poorly with systemic suPAR but were associated with a more severe course of SBP and a worse outcome. In vitro experiments revealed that monocytes, and to a lesser extent neutrophils, secrete suPAR after Toll-like-receptor ligation, which led to rapid urokinase plasminogen activator receptor cleavage followed by increased synthesis. CONCLUSION: Blood and ascitic suPAR levels provide distinct, but relevant prognostic information on the severity of complications in patients with end-stage liver disease.

Survival times of women with metastatic breast cancer starting first-line chemotherapy in routine clinical practice versus contemporary randomised trials.

BACKGROUND: Survival times of women starting first-line chemotherapy for metastatic breast cancer (MBC) in routine clinical practice were determined and compared with those from a systematic review of randomised clinical trials. METHODS: We identified women with MBC starting first-line chemotherapy from June 2003 to February 2011 and recorded their demographics, tumour and treatment characteristics, and survival times from the start of chemotherapy. Their survival distribution was summarised by the following percentiles (represented scenarios for survival): 90th (worst-case), 75th (lower-typical), 25th (upper-typical) and 10th (best-case), which were compared with the same percentiles from our systematic review of first-line chemotherapy trials. RESULTS: The 273 women had a median age of 56 years, and a median time from diagnosis of MBC of 3 months. Eastern Cooperative Oncology Group performance status was 0-1 in 80%. Tumours were hormone receptor positive in 69%, human epidermal growth factor receptor 2 (HER2)-positive in 27% and triple negative in 13%. Survival times in months in routine clinical practice (vs the systematic review) were: 90th percentile 4 (6); 75th percentile 9 (12); median 20 (22); 25th percentile 36 (36) and 10th percentile 61 (56). Independent predictors of overall survival included HER2-positive disease (hazard ratio (HR) 0.49, P = 0.0002), hormone receptor positive disease (HR 0.51, P = 0.0004), Eastern Cooperative Oncology Group performance status 0-1 (HR 0.36, P < 0.0001) and adjuvant chemotherapy (HR 1.86, P = 0.0002). CONCLUSION: Median and better survival times in routine practice were similar to those from randomised clinical trials; however, survival times worse than the median were shorter, likely reflecting patient selection in trials. Oncologists should adjust trial-based survival estimates for patients not meeting typical trial eligibility criteria.

Haematopoietic stem cell recruitment to injured murine liver sinusoids depends on (alpha)4(beta)1 integrin/VCAM-1 interactions.

OBJECTIVE: Evidence suggests haematopoietic stem cells (HSCs) can migrate to injured liver and influence tissue repair. However, mechanisms governing HSC recruitment to injured hepatic microcirculation are poorly understood. These were investigated in vivo following hepatic ischaemia-reperfusion (IR) injury and in vitro using flow-based adhesion assays. DESIGN: Partial IR was induced in anaesthetised WT or PECAM-1(-/-) mice for 90 min. Recruitment of systemically administered HSCs was monitored and effects of function blocking antibodies against alpha(4)beta(1) integrin, CD18, CD44, PECAM-1 or VCAM-1 investigated. The kinetics and molecular events governing adhesion to murine cardiac endothelial cells in vitro were also determined. Effects of conditioned media from IR injured liver on HSC adhesion molecule expression was determined by FACS. RESULTS: Administered HSCs homed predominantly to lungs rather than liver, highlighting a potential therapeutic hurdle. Hepatic HSC recruitment following IR injury was inhibited by anti-alpha(4)beta(1) and anti-VCAM-1 antibodies. A role for alpha(4)beta(1) was also confirmed using flow-based adhesion assays. Incubating HSCs with conditioned media from IR injured liver increased alpha(4)beta(1) expression. CD18, CD44 and PECAM-1 were not involved in recruitment. CONCLUSIONS: This novel study demonstrates that the alpha(4)beta(1)/VCAM-1 pathway mediates HSC recruitment to injured liver. Manipulating this pathway may enhance delivery of HSCs to the liver.

Protease inhibitors selectively block T cell receptor-triggered programmed cell death in a murine T cell hybridoma and activated peripheral T cells.

The hypothesis that cytoplasmic proteases play a functional role in programmed cell death was tested by examining the effect of protease inhibitors on the T cell receptor-mediated death of the 2B4 murine T cell hybridoma and activated T cells. The cysteine protease inhibitors trans-epoxysuccininyl-L-leucylamido-(4-guanidino) butane (E-64) and leupeptin, the calpain selective inhibitor acetyl-leucyl-leucyl-normethional, and the serine protease inhibitors diisopropyl fluorophosphate and phenylmethylsulfonyl fluoride, all showed dose-dependent blocking of the 2B4 death response triggered by the T cell receptor complex and by anti-Thy-1. These protease inhibitors enhanced rather than inhibited IL-2 secretion triggered by T cell receptor cross-linking, showing that they did not act by preventing signal transduction. Growth inhibition induced by cross-linking the 2B4 T cell receptor, measured by inhibition of thymidine incorporation, was not generally blocked by these protease inhibitors. All five of these protease inhibitors enhanced rather than blocked 2B4 cell death triggered by dexamethasone, an agent previously shown to have a death pathway antagonistic with that of the TCR. 2B4 cytolysis by the cytotoxic agents staphylococcal alpha-toxin and dodecyl imidazole, and that caused by hypotonic conditions, was not significantly affected by the five protease inhibitors tested. The selected protease inhibitors blocked both the apoptotic nuclear morphology changes and DNA fragmentation induced by T cell receptor cross-linking, and enhanced both these properties induced by dexamethasone in 2B4 cells. The T cell receptor-induced death of activated murine lymph node T cells and human peripheral blood CD4+ T cells was blocked by both cysteine and serine protease inhibitors, showing that the protease-dependent death pathway also operates in these systems.

CD40 activation induces apoptosis in cultured human hepatocytes via induction of cell surface fas ligand expression and amplifies fas-mediated hepatocyte death during allograft rejection.

We propose that a novel mechanism of hepatocyte apoptosis, involving a cooperative interaction between CD40 and Fas, is involved in the hepatocyte loss of chronic liver allograft rejection. We detected increased hepatocyte expression of Fas, Fas ligand (FasL), and CD40 associated with dropout of centrilobular (acinar zone 3) hepatocytes in chronic allograft rejection. Expression of CD40 ligand (CD40L) was also increased but was largely restricted to CD68(+) macrophages. A functional role for CD40 and Fas in hepatocyte apoptosis was demonstrated in vitro using primary human hepatocytes and the HepG2 cell line in both of which apoptosis was induced, not only by cross-linking Fas directly but also via CD40 activation. Our data suggest that CD40 activation induces apoptosis via Fas because (a) ligation of CD40 upregulated hepatocyte FasL expression, and (b) apoptosis induced via activation of CD40 was prevented by a neutralizing monoclonal antibody to FasL. Thus, CD40 engagement triggers apoptosis of human hepatocytes and might amplify Fas-dependent hepatocyte apoptosis in chronic rejection and other inflammatory liver diseases in which Fas-mediated apoptosis is involved.

Constitutive activation of integrin alpha 4 beta 1 defines a unique stage of human thymocyte development.

Our understanding of thymocyte development and of the positive and negative selection events involved in shaping the repertoire of mature T lymphocytes has been greatly facilitated by the use of transgenic and gene knockout animals. Much less is known about the factors that control the homing and population of the thymus by T cell precursors and the subsequent migration of developing thymocytes through the thymic architecture. As the integrins represent a candidate group of cell surface receptors that may regulate thymocyte development, we have analyzed the expression and function of alpha 4 beta 1 and alpha 5 beta 1 on human thymocytes. A major portion of double positive (CD4+ CD8+) human thymocytes express alpha 4 beta 1 in a constitutively active form and adhere to fibronectin and vascular cell adhesion molecule 1. alpha 4 beta 1 expression is similar on adherent and nonadherent populations, thus, activity reflects the receptor state and not simple expression. The adherent cells are immature, expressing high levels of CD4/CD8 and low levels of CD3 and CD69. In contrast, nonadherent cells possess the phenotype of thymocytes after positive selection, expressing intermediate levels of CD4 and/or CD8 and high levels of CD3 and CD69. The adherent population fails to respond to activation with anti-CD3 and fibronectin, whereas nonadherents exhibit an alpha 5 beta 1-dependent proliferation. Differential regulation of alpha 4 beta 1 and alpha 5 beta 1 receptors may provide a mechanism controlling cellular traffic, differentiation, and positive selection of thymocytes.

Attenuation of Flightless I, an actin-remodelling protein, improves burn injury repair via modulation of transforming growth factor (TGF)-beta1 and TGF-beta3.

BACKGROUND: The pathophysiological mechanisms involved in burn injury repair are still not fully understood but include processes involving cellular proliferation, migration and adhesion. The actin cytoskeleton is intricately involved in these key wound repair processes. Flightless I (Flii), an actin-remodelling protein and transcriptional regulator, is an important regulator of wound healing. OBJECTIVES: To investigate the function of Flii gene expression in burn injury repair. METHODS: Partial-thickness scald wounds were created on Flii heterozygous (Flii(+/-)), wild-type (WT) and Flii transgenic (Flii(Tg/+)) mice. Burns were assessed using histology and immunohistochemistry, real-time quantitative polymerase chain reaction and biochemical analysis. RESULTS: Flii expression, while upregulated in burn injuries, was significantly lower in the wounds of Flii(+/-) vs. WT vs. Flii(Tg/+) mice and healing was improved in Flii(+/-) mice with their burns healing faster than WT and Flii(Tg/+). Pro-scarring transforming growth factor (TGF)-beta1 protein and gene expression were reduced in Flii(+/-) burns while antiscarring TGF-beta3 was significantly elevated. Anti-alpha-smooth muscle actin (alpha-SMA) was decreased in Flii(+/-) burns suggesting a decrease in contractile myofibroblasts in the developing scars. Although Flii is primarily a nuclear and cytoplasmic protein it is also released by wounded cells. Intradermal injection of Flii-neutralizing antibodies (FliAbs) to WT burn wounds significantly improved their healing, indicating a potential novel approach for treating burns. Decreased TGF-beta1 and elevated TGF-beta3 expression were observed in FliAb-treated burns, which may contribute to their observed improvement in healing. CONCLUSIONS: Strategies aimed at reducing Flii expression, for example using neutralizing antibodies, may lead to improved burn outcomes.

Donor HLA-C genotype has a profound impact on the clinical outcome following liver transplantation.

Late allograft dysfunction is a significant problem following liver transplantation and its pathogenesis is uncertain. HLA-C is the major inhibitory ligand for killer immunoglobulin-like receptors (KIRs) that regulate the cytotoxic activity of natural killer (NK) cells. HLA-C alleles can be allocated into two groups, termed HLA-C1 and HLA-C2, based on their KIR specificity. HLA-C2 interactions are more inhibiting to NK cell activation. We studied the clinical importance of HLA-C genotype in a large liver transplant cohort and found that possession of at least one HLA-C2 allele by the donor allograft was associated with less histological evidence of chronic rejection and graft cirrhosis, a 16.2% reduction in graft loss (p = 0.003) (hazard ratio: 2.7, 95% CI 1.4-5.3) and a 13.6% improvement in patient survival (p = 0.01) (hazard ratio: 1.9, 95% CI 1.1-3.3) at 10 years. Transplantation of an HLA-C2 homozygous allograft led to a particularly striking 26.5% reduction in graft loss (p < 0.001) (hazard ratio: 7.2, 95% CI 2.2-23.0) at 10 years when compared to HLA-C1 homozygous allografts. Donor HLA-C genotype is therefore a major determinant of clinical outcome after liver transplantation and reveals the importance of NK cells in chronic rejection and graft cirrhosis. Modulation of HLA-C and KIR interactions represents an important novel approach to promote long-term graft and patient survival.

A role for the integrin alpha6beta1 in the differential distribution of CD4 and CD8 T-cell subsets within the rheumatoid synovium.

OBJECTIVE: CD4 and CD8 T-cell subsets accumulate in distinct microdomains within the inflamed rheumatoid synovium. The molecular basis for their differential distribution remains unclear. Since chemokines and adhesion molecules play an important role in the positioning of leucocytes at sites of inflammation, we tested the hypothesis that the differential expression and function of chemokine and/or adhesion molecules explains why CD4(+) T cells accumulate within perivascular cuffs, whereas CD8(+) T cells distribute diffusely within the tissue. METHODS: Expression of an extensive panel of chemokine receptors and adhesion molecules on matched CD4(+) and CD8(+) T cells from peripheral blood (PB) and synovial fluid (SF) was analysed by multicolour flow cytometry. Migration assays and flow-based adhesion assays were used to assess the functional consequences of any differences in the expression of chemokine and adhesion receptors. RESULTS: CD4(+) and CD8(+) T cells from PB and SF expressed unique yet consistent patterns of chemokine and adhesion receptors. SF CD8(+) T cells were much less promiscuous in their expression of chemokine receptors than SF CD4(+) T cells. The alpha(6)beta(1) integrin was highly expressed on PB CD4(+) T cells, but not on PB CD8(+) T cells. Laminin, the ligand for alpha(6)beta(1), retained CD4(+) T cells, but less so CD8(+) T cells, within inflamed synovial tissue. CONCLUSION: Infiltrating PB CD4(+) T cells, but not CD8(+) T cells, express functional levels of the alpha(6)beta(1) integrin. We propose that this leads to their retention within the rheumatoid synovium in perivascular cuffs, which are defined and delineated by the expression of laminin.

Management of patients undergoing multivalvular surgery for carcinoid heart disease: the role of the anaesthetist.

BACKGROUND: The management of patients with carcinoid heart disease poses two major challenges for the anaesthetist: carcinoid crisis and low cardiac output secondary to right ventricular (RV) failure. Carcinoid crises may be precipitated by the administration of catecholamines and histamine-releasing drugs. METHODS: We analysed a series of 11 patients [six males, median (range) age 60 (42-73) yr] with severe symptomatic carcinoid heart disease who underwent multivalve surgery (right-sided valves, n=8; right- and left-sided valves, n=3) between 2001 and 2007. RESULTS: All patients received octreotide intraoperatively [650 (300-1050) microg] to prevent carcinoid symptoms and vasoplegia. Those patients on a greater preoperative octreotide regime required additional intraoperative octreotide [median (range) dose 320 (300-850) vs 750 (650-1050) mug]. Similarly, the use of greater doses of aprotinin (> 5 KIU) was associated with greater requirements for octreotide [475 (300-700) vs 750 (320-1050) microg] and higher glucose levels (> or =8.5 mmol litre(-1)). Catecholamines were generally required in those patients who presented with a worse New York Heart Association functional class. Overall mortality was 18% (n=2) and only one episode of mild intraoperative carcinoid crisis was observed. CONCLUSIONS: Carcinoid crisis and RV failure still remain the primary challenges for the anaesthesiologist while managing patients with carcinoid heart disease. Our study supports the administration of catecholamines to wean patients off cardiopulmonary bypass, particularly in the presence of myocardial dysfunction. Those patients on higher octreotide dosages may require close intraoperative glucose monitoring. Despite high operative mortality, surgical outcome has been improved potentially due to earlier patient referral and better perioperative management.

CD40 induces apoptosis in carcinoma cells through activation of cytotoxic ligands of the tumor necrosis factor superfamily.

CD40, a tumor necrosis factor (TNF) receptor (TNFR) family member, conveys signals regulating diverse cellular responses, ranging from proliferation and differentiation to growth suppression and cell death. The ability of CD40 to mediate apoptosis in carcinoma cells is intriguing given the fact that the CD40 cytoplasmic C terminus lacks a death domain homology with the cytotoxic members of the TNFR superfamily, such as Fas, TNFR1, and TNF-related apoptosis-inducing ligand (TRAIL) receptors. In this study, we have probed the mechanism by which CD40 transduces death signals. Using a trimeric recombinant soluble CD40 ligand to activate CD40, we have found that this phenomenon critically depends on the membrane proximal domain (amino acids 216 to 239) but not the TNFR-associated factor-interacting PXQXT motif in the CD40 cytoplasmic tail. CD40-mediated cytotoxicity is blocked by caspase inhibitors, such as zVAD-fmk and crmA, and involves activation of caspase 8 and caspase 3. Interestingly, CD40 ligation was found to induce functional Fas ligand, TRAIL (Apo-2L) and TNF in apoptosis-susceptible carcinoma cells and to up-regulate expression of Fas. These findings identify a novel proapoptotic mechanism which is induced by CD40 in carcinoma cells and depends on the endogenous production of cytotoxic cytokines and autocrine or paracrine induction of cell death.

A meta-analysis of sperm donation offspring health outcomes.

Although the use of donor sperm as a treatment modality for male infertility has become common place, the health outcomes for those conceived has been poorly studied. A structured search of the literature using PubMed, EMBASE and Cochrane Reviews was performed to investigate the health outcomes of offspring conceived from donor sperm. Eight studies were eligible and included in the review, and of these, three were included in a meta-analysis. Meta-analysis of clinical outcomes showed that donor sperm neonates are not at increased risk of being born of low birth weight (<2500 g), preterm (<37 weeks) or with increased incidences of birth defects, than spontaneously conceived neonates.