Neutrophil apoptosis is delayed in patients with inflammatory bowel disease

Leukocyte-epithelial interactions and mucosal homeostasis

Many common inflammatory disorders are characterized by the infiltration of neutrophils across epithelial lined (mucosal) surfaces resulting in disruption of critical barrier function that protects from microbes and noxious agents. In such conditions, disease symptoms are complex but directly related to leukocyte effects on the barrier and epithelial cell function. It is now highly regarded that cellular factors such as cytokines and receptor-ligand interactions mediating adhesion of leukocytes to epithelial cells have potent effects on epithelial homeostasis, defined by coordinated proliferation, migration, differentiation, and regulated cell shedding. Certain cytokines, for example, not only alter leukocyte interactions with epithelia through changes in expression of adhesion molecules but also affect barrier function through alterations in the composition and dynamics of intercellular junctions. In particular, inflammation-induced loss of many tight junction molecules, in part, can account for dysregulated cellular proliferation, migration, survival, and barrier function. This review will highlight how neutrophils interact with epithelial cells with particular focus on adhesion molecules involved and signaling events that play roles in regulating mucosal homeostasis and pathobiology. A better understanding of these molecular events may provide new ideas for therapeutics directed at attenuating consequences of pathologic inflammation of mucosal surfaces.

Evaluation of neutrophil apoptosis in horses with acute abdominal disease

OBJECTIVE

To quantify peripheral blood neutrophil apoptosis in equine patients with acute abdominal disease (ie, colic) caused by strangulating or nonstrangulating intestinal lesions and compare these values with values for horses undergoing elective arthroscopic surgery.

ANIMALS

20 client-owned adult horses.

PROCEDURES

Peripheral blood was collected from horses immediately prior to and 24 hours after surgery for treatment of colic (n = 10) or elective arthroscopic surgery (10), and neutrophils were counted. Following isolation by means of a bilayer colloidal silica particle gradient and culture for 24 hours, the proportion of neutrophils in apoptosis was detected by flow cytometric evaluation of cells stained with annexin V and 7-aminoactinomycin D. Values were compared between the colic and arthroscopy groups; among horses with colic, values were further compared between horses with and without strangulating intestinal lesions.

RESULTS

Percentage recovery of neutrophils was significantly smaller in preoperative samples (median, 32.5%) and in all samples combined (35.5%) for the colic group, compared with the arthroscopy group (median, 66.5% and 58.0%, respectively). No significant differences in the percentages of apoptotic neutrophils were detected between these groups. Among horses with colic, those with strangulating intestinal lesions had a significantly lower proportion of circulating apoptotic neutrophils in postoperative samples (median, 18.0%) than did those with nonstrangulating lesions (66.3%).

CONCLUSIONS AND CLINICAL RELEVANCE

The smaller proportion of apoptotic neutrophils in horses with intestinal strangulation suggested that the inflammatory response could be greater or prolonged, compared with that of horses with nonstrangulating intestinal lesions. Further investigations are needed to better understand the relationship between neutrophil apoptosis and inflammation during intestinal injury.

Effects of preoperative leukocytapheresis on inflammatory cytokines following surgery for ulcerative colitis: a prospective randomized study

Targeted extracorporeal granulocyte and monocyte apheresis (GMA) has produced clinical efficacy together with down modulation of specific inflammatory cytokines in patients with ulcerative colitis (UC). This study was to investigate if preoperative GMA produces immunological effect on dysregulated immune activity after restorative proctocolectomy (RPC) in patients with UC. Forty patients requiring RPC were included. Twenty randomly selected patients received five GMA sessions with the Adacolumn over two consecutive weeks before RPC (GMA group). RPC was performed within 2 weeks following the last GMA session. The other 20 patients did not receive GMA before RPC (non-GMA group). Blood samples were obtained immediately before surgery, at 1 h after surgery, and on postoperative Days 1, 3, and 7 from all patients. Abdominal exudate was obtained from the drainage tube at 1 h after surgery, and on postoperative Days 1, 3, and 7. Concentrations of interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α in plasma and peritoneal fluid from a drainage tube were measured by enzyme linked immunosorbent assay. Between the two groups, patients were matched with respect to age, sex, UC duration, severity, extent and the dose of prednisolone at surgery. IL-1β, IL-6, and TNF-α levels in plasma and peritoneal fluid were not significantly different between the two groups during the entire study period. Based on the assays of IL-1β, IL-6, and TNF-α levels in the plasma and the peritoneal fluid, this study did not find any effect on these inflammatory cytokines by preoperative GMA in patients with UC who underwent RPC.

Efficacy, safety and cost analyses in ulcerative colitis patients undergoing granulocyte and monocyte adsorption or receiving prednisolone

Background

Patients with ulcerative colitis (UC) are treated with prednisolone (PSL), which causes adverse side effects. Extracorporeal granulocyte/monocyte adsorption (GMA) with an Adacolumn depletes elevated/activated myeloid lineage leucocytes as sources of inflammatory cytokines. We were interested to evaluate the efficacy, safety and the treatment cost for PSL and GMA.

Methods

Forty-one patients with active UC had achieved remission with GMA, at 1 or 2 sessions/week, up to 10 sessions (n=24) or with orally administered PSL (1mg/kg bodyweight, n=17). Clinical activity index (CAI) ≤4 was considered clinical remission. Following remission, patients received 5-aminosalicylic acid (2250-3000mg/day) or sulphasalazine (4000-6000mg/day) as maintenance therapy and were followed for 600 days. The total treatment cost was assessed based on 1€=150JPY.

Results

PSL was tapered after two weeks, and discontinued when a patient achieved remission. The average time to the disappearance of at least one major UC symptom (haematochezia, diarrhoea, or abdominal discomfort) was 15.3 days in the GMA group and 12.7 days in the PSL group, while time to remission was 27.9 days in the GMA group and 27.6 days in the PSL group, CAI 0.8 and 2.0, respectively. The Kaplan-Meier plots showed similar remission maintenance rates over the 600 days follow-up period. The average medical cost was 12739.4€/patient in the GMA group and 8751.3€ in the PSL group (P<0.05). In the GMA group, 5 transient adverse events were observed vs 10 steroid related adverse events in the PSL group (P<0.001).

Conclusions

In appropriately selected patients, GMA has significant efficacy with no safety concern. The higher cost of GMA vs PSL should be compromised by good safety profile of this non-pharmacological treatment intervention.

Assessment of neutrophil-lymphocyte ratio in ulcerative colitis: a promising marker in predicting disease severity

BACKGROUND AND AIM

In order to diagnosis and monitor the disease activity of ulcerative colitis (UC), serum biomarkers are generally used, but none of them are specific for intestinal inflammation. It is therefore desirable in clinical practice to be able to assess disease activity with simple, inexpensive and objective tools. The objective of the present study was to assess whether the neutrophil-lymphocyte ratio (NLR) would be useful in predicting disease severity in UC patients who had not received corticosteroid or immunosuppressive drugs within a defined period of time. Additionally, a possible relationship of NLR with other inflammatory markers in UC patients was also investigated.

METHODS

We designed a retrospective study examining the utility of NLR in estimating disease severity in UC patients admitted to our hospital between 2008 and 2011. In total, 119 patients with active UC and 77 patients with inactive UC were enrolled in the study group, and 59 age and gender matched healthy subjects were included as the control group. Disease activity was assessed using Truelove and Witts criteria.

RESULTS

In the active UC group, NLR values were found to be elevated compared to inactive UC patients and controls (3.22 ± 1.29, 1.84 ± 0.69 and 2.01 ± 0.64, respectively). Using ROC statistics, a cut-off value of 2.16 indicated the presence of active disease with a sensitivity of 81.8% and a specificity of 80.5% (positive predictive value [PPV] 86.8%, negative predictive value [NPV] 73.8%). NLR values were found to be correlated with WBC and ESR levels.

CONCLUSIONS

The present study revealed that NLR is increased in active UC. Peripheral blood NLR can reflect disease activity and can be used as an additional marker for estimating intestinal inflammation.

Selective Granulocyte and Monocyte Apheresis as a Non-Pharmacological Option for Patients with Inflammatory Bowel Disease

Ulcerative colitis and Crohn's disease are the two most prevalent inflammatory bowel diseases. In both cases, the medically refractory and steroid-dependent type presents a therapeutic challenge. To help resolve this problem, a mainly Japanese team developed a new therapeutic option. There are two systems, both of which are able to selectively remove the main mediators of the disease, namely the activated pro-inflammatory cytokine-producing granulocytes and monocytes/macrophages, from the patient's blood circulation (GMA = granulocyte monocyte apheresis). One of the two systems is the Adacolumn( (®) ) (Immunoresearch Laboratories, Takasaki, Japan) consisting of the ADA-monitor and a single-use column, which contains approximately 35,000 cellulose acetate beads. The exact mode of action is not yet sufficiently understood, but however, a modulation of the immune system takes place. As a result, less pro-inflammatory cytokines are released. Furthermore, the production of anti-inflammatory interleukin-1 receptor antagonist is increased, and the apoptosis of granulocytes boosted. The decreased LECAM-1-expression on leukocytes impedes the leukotaxis to the inflamed tissue, and CD10-negative immature granulocytes appear in the peripheral blood. Another effect to be mentioned is the removal of the peripheral dendritic cells and the leachate of regulatory T cells (T-regs). The second system is the Cellsorba( (®) ) FX Filter (Asahi Medical, Tokyo, Japan). The range of efficiency, the indication, and the procedure are very similar to the Adacolumn. Solely the additional removal of lymphocytes can possibly limit the implementation since lymphopenia can increase the risk of autoimmune disease. Both systems provide a low-risk therapy with few adverse reactions. ASFA recommendations for GMA in inflammatory bowel disease are 2B due to the fact that not enough randomized double-blind studies are available to proof the efficacy of this treatment.

The role of neutrophils during intestinal inflammation

Polymorphonuclear leukocytes or neutrophils play a critical role in the maintenance of intestinal homeostasis. They have elegant defense mechanisms to eliminate microbes that have translocated across a single layer of mucosal epithelial cells that form a critical barrier between the gut lumen and the underlying tissue. During the inflammatory response, neutrophils also contribute to the recruitment of other immune cells and facilitate mucosal healing by releasing mediators necessary for the resolution of inflammation. Although the above responses are clearly beneficial, excessive recruitment and accumulation of activated neutrophils in the intestine under pathological conditions such as inflammatory bowel disease is associated with mucosal injury and debilitating disease symptoms. Thus, depending on the circumstances, neutrophils can be viewed as either good or bad. In this article, we summarize the beneficial and deleterious roles of neutrophils in the intestine during health and disease and provide an overview of what is known about neutrophil function in the gut.

Current status and future perspectives of leukocytapheresis for inflammatory bowel disease

Ulcerative colitis (UC) and Crohn's disease (CD) comprise the idiopathic inflammatory bowel diseases (IBD) of the gut. The etiology of IBD is poorly understood, but an autoimmune disturbance has been suggested to play an important role in this incurable disease. Extracorporeal leukocytapheresis (CAP) is an additional adjunct for IBD patients refractory to other conventional therapies, including steroids. The primary aim of CAP should be to suppress such unwanted immunological response by removing circulating inflammatory cells from the blood stream. The first decade has been passed since CAP was approved by Japanese social health insurance policy. It is therefore now an appropriate opportunity to upgrade and summarize our current understandings and/or future perspectives of this unique non-pharmacological and non-surgical strategy for IBD patients. According to several clinical and basic research reports, an early introduction of CAP should produce higher efficacy as compared with CAP applied sometime after a clinical relapse. Likewise, CAP therapy adjusted to patients' body-weight as well as two treatment sessions per week (intensive regimen) should benefit the efficacy rate. The etiology of IBD is not fully elucidated yet. As a result, the major therapeutic strategies in the Western world have been immunosuppressive therapy, including biologics. CAP is an unusual treatment modality for IBD because it seems to have both effectiveness and safety, which should generally be balanced in this type of illness. We now have to develop future strategies with and without combining biologics to improve the quality of life of IBD patients.

Decreased neutrophil apoptosis in quiescent ANCA-associated systemic vasculitis

Background

ANCA-Associated Systemic Vasculitis (AASV) is characterized by leukocytoclasis, accumulation of unscavenged apoptotic and necrotic neutrophils in perivascular tissues. Dysregulation of neutrophil cell death may contribute directly to the pathogenesis of AASV.

Methods

Neutrophils from Healthy Blood Donors (HBD), patients with AASV most in complete remission, Polycythemia Vera (PV), Systemic Lupus Erythematosus (SLE), Rheumatoid Arthritis (RA) and renal transplant recipients (TP) were incubated in vitro, and the rate of spontaneous apoptosis was measured by FACS. Plasma levels of cytokines and sFAS were measured with cytometric bead array and ELISA. Expression of pro/anti-apoptotic factors, transcription factors C/EBP-α, C/EBP-β and PU.1 and inhibitors of survival/JAK2-pathway were measured by real-time-PCR.

Results

AASV, PV and RA neutrophils had a significantly lower rate of apoptosis compared to HBD neutrophils (AASV 50±14% vs. HBD 64±11%, p<0.0001). In RA but not in AASV and PV, low apoptosis rate correlated with increased plasma levels of GM-CSF and high mRNA levels of anti-apoptotic factors Bcl-2A1 and Mcl-1. AASV patients had normal levels of G-CSF, GM-CSF and IL-3. Both C/EBP-α, C/EBP-β were significantly higher in neutrophils from AASV patients than HBD. Levels of sFAS were significantly higher in AASV compared to HBD.

Conclusion

Neutrophil apoptosis rates in vitro are decreased in AASV, RA and PV but mechanisms seem to differ. Increased mRNA levels of granulopoiesis-associated transcription factors and increased levels of sFAS in plasma were observed in AASV. Additional studies are required to define the mechanisms behind the decreased apoptosis rates, and possible connections with accumulation of dying neutrophils in regions of vascular lesions in AASV patients.

CD15+/CD16low human granulocytes from terminal cancer patients: granulocytic myeloid-derived suppressor cells that have suppressive function

Myeloid-derived suppressor cells (MDSCs) are a subpopulation of myeloid cells with immunosuppressive function whose numbers are increased in conditions such as chronic infection, trauma, and cancer. Unlike murine MDSCs defined as CD11b(+)/Gr-1(+), there are no specific markers for human MDSCs. The goal of this study was to delineate a specific human MDSCs subpopulation in granulocytes from terminal cancer patients and investigate its clinical implications. Here, we show that the CD15(+)/CD16(low) subset was increased in terminal cancer patients compared with healthy donors (P = 0.009). Phorbol 12-myristate 13-acetate-activated granulocytes (CD16(low)/CD66b(++)/CD15(+)) that have a phenotype similar to MDSCs from cancer patients, effectively suppressed both proliferation and cytotoxicity of normal T cells. Among cancer patients, T-cell proliferation was highly suppressed by granulocytes isolated from terminal cancer patients with a high proportion of CD15(+)/CD16(low) cells. Patients with low peripheral blood levels of CD15(+)/CD16(low) cells had significantly longer survival than those with high levels (P = 0.0011). Patients with higher levels of CD15(+)/CD16(low) also tended to have poor performance status (P = 0.05). These data suggest that CD15(+)/CD16(low) granulocytes found in terminal cancer patients may play a role in the progression of cancer by inhibiting tumor immunity.

The mode of actions of the Adacolumn therapeutic leucocytapheresis in patients with inflammatory bowel disease: a concise review

Patients with active inflammatory bowel disease (IBD) have elevated and activated myeloid leucocytes which infiltrate the colonic mucosa in vast numbers. Myeloid leucocytes such as the CD14(+) CD16(+) monocytes are major sources of tumour necrosis factor (TNF)-α, and therefore selective granulocyte/monocyte (GM) adsorption (GMA) should promote remission or enhance efficacy of pharmacological therapy. However, studies in IBD have reported both impressive as well as disappointing efficacy outcomes, indicating that patients' demographic factors might determine responders or non-responders to GMA. Nonetheless, this non-drug intervention has an excellent safety profile, and therapeutic GMA is expected to expand. In this review, attempts have been made to compile an update on the mode of actions (MoA) of the Adacolumn GMA. The MoA of GMA appears to be more than adsorption of excess neutrophils and TNF-producing CD14(+) CD16(+) monocytes per se. Adsorbed GMs release interleukin (IL)-1 receptor antagonist, hepatocyte growth factor and soluble TNF receptors, which are anti-inflammatory. Additionally, a sustained increase in lymphocytes including the regulatory CD4(+) CD25(+) T cells (lymphocyte sparing) is seen post-GMA. The impact of GMA on the immune system is potentially very interesting in the context of treating immune-related diseases. Future studies are expected to add intriguing insights to the MoA of GMA.

The mode of actions of the Adacolumn therapeutic leucocytapheresis in patients with inflammatory bowel disease: a concise review

Patients with active inflammatory bowel disease (IBD) have elevated and activated myeloid leucocytes which infiltrate the colonic mucosa in vast numbers. Myeloid leucocytes such as the CD14(+) CD16(+) monocytes are major sources of tumour necrosis factor (TNF)-α, and therefore selective granulocyte/monocyte (GM) adsorption (GMA) should promote remission or enhance efficacy of pharmacological therapy. However, studies in IBD have reported both impressive as well as disappointing efficacy outcomes, indicating that patients' demographic factors might determine responders or non-responders to GMA. Nonetheless, this non-drug intervention has an excellent safety profile, and therapeutic GMA is expected to expand. In this review, attempts have been made to compile an update on the mode of actions (MoA) of the Adacolumn GMA. The MoA of GMA appears to be more than adsorption of excess neutrophils and TNF-producing CD14(+) CD16(+) monocytes per se. Adsorbed GMs release interleukin (IL)-1 receptor antagonist, hepatocyte growth factor and soluble TNF receptors, which are anti-inflammatory. Additionally, a sustained increase in lymphocytes including the regulatory CD4(+) CD25(+) T cells (lymphocyte sparing) is seen post-GMA. The impact of GMA on the immune system is potentially very interesting in the context of treating immune-related diseases. Future studies are expected to add intriguing insights to the MoA of GMA.

Feasibility and safety of granulocytapheresis in Crohn's disease: a prospective cohort study

BACKGROUND AND OBJECTIVE

This study evaluated the feasibility and safety of granulocytapheresis (GCAP) in inducing and maintaining remission in refractory Crohn's disease. The relationship between the clinical outcomes and the location (ileal or ileocolonic) of disease was also assessed.

PATIENTS

We evaluated 16 patients with ileal location (group A), 14 with ileocolonic location (group B). The patients underwent five sessions (1 session/wk) of GCAP (Adacolumn(TM)). CDAI was measured at the end of the GCAP, at 6, 9 and 12 months.

RESULTS AND CONCLUSIONS

No major complications were observed. At the end of GCAP, 19 (63.3%) patients showed a clinical remission: 10 (62.5%) in group A versus 9 (64.2%) in group B. At 6 months, 16 (53.3%) of the cases had maintained remission: 9 (56.2%) in group A versus 7 (50.0%) in group B. At 9 months, 13 (43.3%) patients had maintained remission: 7 (43.7%) in group A versus 6 (42.8%) in group B. At 12 months, 12 (40%) patients were still in clinical remission: 7 (43.7%) in group A versus 5 (35.7%) in group B. Risk of relapse was not related to disease location. The procedure was well tolerated and feasible in an important percentage of Crohn's disease patients.

Diammonium glycyrrhizinate up-regulates the expression of Foxp3 mRNA in rats with ulcerative colitis

AIM: To evaluate the protective effect of diammonium glycyrrhizinate (DG) against ulcerative colitis in rats and to investigate potential mechanisms involved.

METHODS: Thirty Sprague-Dawley (SD) rats were equally randomized into normal control group, model group and DG group. Ulcerative colitis was induced in the DG group and model group by rectal administration of trinitrobenzene sulphonic acid (TNBS). Disease activity index (DAI) and histological damage were evaluated, and the expression of forkhead box P3 (Foxp3) mRNA in peripheral blood mononuclear cells (PBMCs) was detected by reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS: Both DAI and histological damage score were significantly higher in the model group than in the normal control group (DAI: 7.1 ± 0.2 vs 0.3 ± 0.6, P < 0.05; histological damage score: 6.7 ± 0.5 vs 0.9 ± 0.2, P < 0.05). Compared with the model group, DAI and histological damage score were significantly improved in the DG group (DAI: 3.1 ± 0.6 vs 7.1 ± 0.2, P < 0.05; histological damage score: 3.3 ± 0.4 vs 6.7 ± 0.5, P < 0.05). Compared with the normal control group, the expression of Foxp3 mRNA was down-regulated in PBMCs in the model group (0.51 ± 0.34 vs 1.09 ± 0.38, P < 0.05). DG treatment significantly up-regulated the expression of Foxp3 mRNA in PBMCs (0.92 ± 0.53 vs 0.51 ± 0.34, P < 0.05).

CONCLUSION: DG can ameliorate colonic inflammation in rats with ulcerative colitis possibly by increasing the expression of Foxp3 mRNA in PBMCs.

Crohn's disease as an immunodeficiency

The pathogenesis of Crohn's disease (CD) has widely been regarded as the consequence of a dysregulated T-cell-mediated response to intestinal microbes, and the majority of the worldwide research effort has focused on characterizing and treating the chronic inflammatory phase of the disease. However, recent molecular biological and clinical investigations indicate that CD is actually a primary immunodeficiency. At first counter-intuitive, the apparent paradox of a pathogenic innate immune defect can be linked mechanistically to the granulomatous chronic inflammation characteristic of the disease. Genome-wide association studies have corroborated the involvement of innate immune dysfunction in the pathogenesis of CD, but less than 20% of the heritable risk is accounted for. By contrast, in vitro and in vivo stimulation of the immune system has highlighted novel areas of interest that may lead to the development of targeted therapeutic and diagnostic tools.

Proteinase-activated receptors induce interleukin-8 expression by intestinal epithelial cells through ERK/RSK90 activation and histone acetylation

Proteinase-activated receptors (PARs) are involved in both inflammation and tumorigenesis in epithelial cells. Interleukin (IL)-8 is a potent chemoattractant and is also involved in angiogenesis. The molecular mechanism whereby PARs induce epithelial IL-8 expression is not known. In HT-29 colonic epithelial cells, PAR(1) or PAR(2) agonists stimulated the expression of IL-8 through a NF-kappaB-dependent pathway without inducing IkappaB degradation and disassociation of IkappaB from NF-kappaB. Further studies revealed that PAR activation induced the phosphorylation of p65 at Ser-276 in the nucleus, which increased the recruitment of histone acetyltransferase (HAT) p300 to p50. Inhibition of ERK activation completely blocked PAR-induced IL-8 expression, phosphorylation of p65 and HAT activity. We also demonstrated that RSK p90 was the downstream kinase that mediated ERK-induced nuclear p65 phosphorylation. In conclusion, activation of either PAR(1) or PAR(2) stimulated the transcriptional up-regulation of IL-8 in HT-29 colonic epithelial cells through a pathway that involved ERK/RSK p90, NF-kappaB phosphorylation, and HAT activity. These studies provide evidence of a new role for serine proteinases and PARs in the regulation of gene expression in colonic inflammation and tumorigenesis.

The modifying effects of green tea polyphenols on acute colitis and inflammation-associated colon carcinogenesis in male ICR mice

Reactive oxygen species (ROS) have been implicated as mediators of intestinal inflammation and carcinogenesis. Although green tea polyphenols (GTP) have anticancer property as antioxidants they also generate ROS in vitro. In this study, we investigated the modifying effects of GTP on dextran sulfate sodium (DSS)-induced acute colitis and on 1,2-dimethylhydrazine (DMH) and DSS-induced colon carcinogenesis in male ICR mice. At sacrifice after 6 days, the colon shortening induced by 2% DSS was unchanged by 0.1% and 0.25% GTP, but increased by 0.5% and 1% GTP-containing diet. The expression of interleukin-1beta and macrophage-migration inhibitory factor in the DSS + 0.1% GTP group were lower than the DSS alone group, whereas the expression levels were increased in the DSS + 0.5% GTP and DSS + 1% GTP groups when compared with the DSS alone group. In a subsequent experiment to determine the effects of 0.01-1% GTP on inflammation-associated colon carcinogenesis induced by DMH/DSS, 0.5 and 1% doses of GTP failed to prevent the development of multiple colon tumors, rather, they tended to increase it. Our results thus indicate that the modifying effects of GTP on DSS-induced acute colitis and DMH/DSS-induced colon carcinogenesis depends upon its dosage and the expression of proinflammatory cytokines.

An open-label prospective randomized multicenter study shows very rapid remission of ulcerative colitis by intensive granulocyte and monocyte adsorptive apheresis as compared with routine weekly treatment

OBJECTIVES

Granulocyte and monocyte adsorptive apheresis (GMA) has shown efficacy in patients with active ulcerative colitis (UC). However, with routine weekly treatment, it may take several weeks to achieve remission, and to date, the efficacy of a more frequent treatment schedule remains unknown. The aim of this study was to assess the clinical efficacy and safety of intensive GMA treatment in patients with active UC.

METHODS

This was an open-label, prospective, randomized multicenter study to compare an intensive, two GMA sessions per week, with the routine, one GMA session per week. A total of 163 patients with mild-to-moderately active UC were randomly assigned to routine weekly treatment or intensive treatment. The maximum number of sessions of GMA permitted was 10. However, when patients achieved remission, GMA was discontinued. Remission rate at the end of the study, time to remission, and adverse events were assessed in both groups.

RESULTS

Of the 163 patients, 149 were available for efficacy analysis as per protocol, 76 were in weekly GMA, and 73 were in intensive GMA. At the end of the study period, clinical remission was achieved in 41 of 76 patients (54.0%) in weekly GMA and in 52 of 73 patients (71.2%) in intensive GMA (P=0.029). The mean time to remission was 28.1+/-16.9 days in the weekly GMA treatment group and 14.9+/-9.5 days in the intensive GMA group (P<0.0001). Intensive GMA was well tolerated without GMA-related serious adverse side effects.

CONCLUSIONS

Intensive GMA in patients with active UC seems to be more efficacious than weekly treatment, and significantly reduced the patients' morbidity time without increasing the incidence of side effects.

Diminished macrophage apoptosis and reactive oxygen species generation after phorbol ester stimulation in Crohn's disease

BACKGROUND

Crohn's Disease (CD) is a chronic relapsing disorder characterized by granulomatous inflammation of the gastrointestinal tract. Although its pathogenesis is complex, we have recently shown that CD patients have a systemic defect in macrophage function, which results in the defective clearance of bacteria from inflammatory sites.

METHODOLOGY/PRINCIPAL FINDINGS

Here we have identified a number of additional macrophage defects in CD following diacylglycerol (DAG) homolog phorbol-12-myristate-13-acetate (PMA) activation. We provide evidence for decreased DNA fragmentation, reduced mitochondrial membrane depolarization, impaired reactive oxygen species production, diminished cytochrome c release and increased IL-6 production compared to healthy subjects after PMA exposure. The observed macrophage defects in CD were stimulus-specific, as normal responses were observed following p53 activation and endoplasmic reticulum stress.

CONCLUSION

These findings add to a growing body of evidence highlighting disordered macrophage function in CD and, given their pivotal role in orchestrating inflammatory responses, defective apoptosis could potentially contribute to the pathogenesis of CD.

Oxazolone-induced enterocolitis in zebrafish depends on the composition of the intestinal microbiota

BACKGROUND & AIMS

The pathogenesis of inflammatory bowel disease involves dysfunctional mucosal immune responses to commensal bacteria in genetically predisposed hosts. Interactions between host cells and bacteria are complicated, making it a challenge to assess their relative contribution to intestinal pathology. We developed a zebrafish model of enterocolitis to study these interactions.

METHODS

Enterocolitis was induced by intrarectal administration of the hapten oxazolone in adult wild-type and myeloperoxidase-reporter transgenic zebrafish in the presence or absence of antibiotics. Intestinal inflammation was evaluated by histological and flow cytometry analyses and cytokine profiling with quantitative real-time polymerase chain reaction. Changes in the composition of the intestinal microbiota following antibiotic administration were assessed by 16SrRNA sequencing and bacterial load was quantified by culture on nonselective media (colony-forming units).

RESULTS

In zebrafish, the infiltrate and severity of oxazolone-induced enterocolitis are influenced by the composition of the microbiota. Inflammation is characterized by granulocyte influx; epithelial damage; goblet cell depletion; and increased expression of interleukin-1beta, tumor necrosis factor-alpha, and interleukin-10. Zebrafish given vancomycin had bacterial populations dominated by Fusobacteria and reduced enterocolitis scores, intestinal damage, and percentages of infiltrating neutrophils and eosinophils. In contrast, zebrafish given colistin sulphate had a predominance of proteobacteria and reduced eosinophil and lymphocyte infiltration, but enterocolitis scores were not reduced.

CONCLUSIONS

In zebrafish with oxazolone-induced enterocolitis, components of the intestinal microbiota affect the severity and composition of the intestinal infiltrate.

Treating ulcerative colitis by Adacolumn therapeutic leucocytapheresis: clinical efficacy and safety based on surveillance of 656 patients in 53 centres in Japan

BACKGROUND/AIM

The Adacolumn selectively depletes granulocytes and monocytes/macrophages, which are thought to be part of the immunopathogenesis of ulcerative colitis. This work aims at evaluating the safety and clinical efficacy of the Adacolumn in patients with ulcerative colitis in large population-based data sets.

METHODS

The Adacolumn post marketing surveillance in Japan was undertaken on 697 patients in 53 medical institutions over 7 years from 29 October 1999 to 28 October 2006. Clinical efficacy and safety data were provided by patients' physicians in the participating institutes.

RESULTS

Safety was evaluated in all the 697 patients and efficacy in 656 patients. At entry, 92% of the patients were on salicylates, 74% on prednisolone and only 9% on immunomodulators. Approximately 40% of patients had severe ulcerative colitis and over 70% had ulcerative colitis that was refractory to conventional medications. There was no serious adverse events; mild to moderate adverse events were seen in 7.7% of the patients. The overall response (remission or significantly improved) was 77.3%; the remission rate based on clinical activity index was 71.1%, while 17.1% remained unchanged and 5.6% worsened. Patients were subgrouped into severe, moderate and mild ulcerative colitis based on clinical activity index (n=578), the response rates were 63.2%, 65.7% and 80.4%, respectively (P<0.001). Endoscopic assessment of efficacy showed very significant mucosal healing, Matts' endoscopic index improved from 3.2+/-0.04 to 2.1+/-0.7 (n=219, P<0.001); reduction in prednisolone dose (P<0.0001); leucocyte count (n=358, P<0.0001) and C-reactive protein (n=314, P<0.0001). Patients who received > or =6 Adacolumn sessions (n=319) did better than patients who received < or =5 sessions (n=188, P=0.004) and multivariate logistic regression analysis revealed that baseline granulocyte count was the strongest predictor of clinical response to Adacolumn (P=0.0191, odds ratio 1.151).

CONCLUSION

This post marketing surveillance provides the largest ever efficacy and safety data on the Adacolumn therapeutic leucocytapheresis in patients with ulcerative colitis. As a non-pharmacologic treatment for patients with active ulcerative colitis most of whom were refractory to conventional drug therapy, the observed efficacy was very significant. Baseline granulocyte count was convincingly an independent predictor of clinical response.

Delayed neutrophil apoptosis in patients with unstable angina: relation to C-reactive protein and recurrence of instability

AIMS

To investigate spontaneous polymorphonuclear neutrophils (PMNs) apoptosis in unstable angina (UA) and its association with recurrence of instability.

METHODS AND RESULTS

We compared PMNs apoptotic rate at 4 and 24 h in patients with UA, stable angina (SA), and controls (H) with two different protocols by flow cytometry. We measured apoptotic rate of isolated PMNs (Protocol 1) in 30 UA patients, 13 SA patients, and 34 H; and apoptosis of PMNs in whole blood culture (Protocol 2) in further 10 UA patients, 7 SA patients, and 6 H. Serum high-sensitivity C-reactive protein was also measured. Polymorphonuclear neutrophils of UA patients showed a decreased apoptotic rate compared with SA patients and H at 4 h in Protocol 1 (both P < 0.01), and at 24 h in Protocol 2 (P < 0.05 and <0.01, respectively). In overall population, a negative correlation was found between apoptotic rate at 4 h and high-sensitivity C-reactive protein levels (P < 0.01). Six among 40 patients with UA had early recurrence of symptoms and their apoptotic rate was significantly reduced compared with UA patients without recurrence of symptoms (P = 0.024).

CONCLUSIONS

Our study demonstrates delayed PMN apoptosis in UA. This alteration might be involved in the persistence of inflammatory activation and affects recurrence of instability.

A role for IL-18 in human neutrophil apoptosis

Decreased neutrophil apoptosis is associated with persistent inflammation, the severity of which correlates with serum IL-18 levels. IL-18 receptors as well as Toll-like receptors, including Toll-like receptor 4, a receptor for LPS, possess a highly conserved intracellular domain called "Toll-IL-1R domain" and activate overlapping signaling pathways. Here, we show that IL-18 modulates neutrophil apoptosis and compare its mechanism of action with LPS. We found that both IL-18 and LPS decreased neutrophil apoptosis in a similar dose- and time-dependent fashion. However, pretreatment with the phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 increased apoptosis more effectively in IL-18- than in LPS-stimulated cells, whereas the ERK inhibitor PD98059 had the same effect in both. In contrast, the p38 mitogen-activated protein kinase (MAPK) inhibitor SB203580 had no influence on apoptosis at all. Neutrophils constitutively expressed mRNA for IL-18 receptor beta, but little or no receptor alpha, both of which increased during coculture with either IL-18 or LPS in a time- and dose-dependent manner. Of the Bcl-2 family, antiapoptotic A1/Bfl-1 tended to increase on IL-18 and LPS stimulation, but was further increased despite increased apoptosis in the presence of MAPK inhibitors. Thus, human neutrophils can express mRNA for IL-18 receptors alpha and beta, and IL-18, like LPS, inhibits neutrophil apoptosis by activating PI3K and ERK pathways but not p38MAPK. However, PI3K may play more important role(s) in IL-18- than in LPS-induced inhibition of apoptosis. Mitogen-activated protein kinases seem to mediate antiapoptotic signals through factors other than Bcl-2 gene family expression.

Cytapheresis in patients with severe ulcerative colitis after failure of intravenous corticosteroid: a long-term retrospective cohort study

BACKGROUND/AIMS

Cytapheresis (CAP) is a novel strategy for ulcerative colitis (UC). However, there is insufficient data on the long-term outcome of UC patients who achieve remission by CAP. This study involved patients with severe UC who refracted to intravenous (iv) corticosteroid.

METHODS

Forty-seven UC patients who had received CAP therapy for the first time within 1 year after UC diagnosis were followed for 36 months. One of the inclusion criteria was a clinical activity index (CAI) of >/=7 points at the end of a 2-week iv course of corticosteroid therapy. CAP therapy consisted of ten sessions over 10 weeks.

RESULTS

CAP induced clinical remission (CAI</=4) in 70.2% patients (33/47). The number of submissions for colectomy was higher for severe UC at entry (CAI>/=12, n=25) than for moderately severe UC at entry (7</=CAI<12, p=15; p<0.02). The cumulative rates of avoiding surgery and relapse were 54.5% and 24.2%, respectively, at 36 months in patients who responded to CAP therapy. This was similar to that of iv cyclosporine reported recently.

CONCLUSIONS

This study suggest that CAP is an effective therapy in patients who are refractory to conventional medications including iv corticosteroid. Increased remission rates should be expected in refractory patients with moderately severe UC.

Quantitive cytokine mRNA expression profiles in the colonic mucosa of patients with steroid naïve ulcerative colitis during active and quiescent disease

BACKGROUND

Cytokines have validated roles in the immunopathogenesis of inflammatory bowel disease (IBD). This study was to investigate the expressions of tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, IL-8, and IL-10 mRNAs in the colonic mucosa of patients with ulcerative colitis (UC) during active and quiescent UC.

METHODS

At colonoscopy, biopsies were taken from inflamed and non-inflamed mucosa of patients with steroid-naive UC (n = 15), non-IBD inflammatory colitis controls (ICC, n = 6), and non-colitis controls (NCC, n = 14). The presence of extensive mononuclear cells and neutrophils infiltrate in the lamina propria, cryptitis, and epithelial damage defined an inflammatory lesion in the mucosa. Quantitative cytokine mRNA expressions in biopsies were measured by real-time polymerase chain reaction (PCR).

RESULTS

Of 15 UC patients, 3 remitted with 5-aminosalicylate and 11 received granulocytapheresis; of these, 10 remitted. At baseline, IL-6, IL-8, TNF-alpha, and IL-10 mRNAs were high in inflamed mucosa compared with NCC (P < 0.01). In active UC, IL-6, IL-8 and IL-10 mRNAs were high compared with non-inflamed mucosa (P = 0.03, P = 0.03, P < 0.05, respectively). Both TNF-alpha mRNA (P = 0.03) and IL-6 mRNA (P = 0.04) were higher in UC compared with ICC. Even in non-inflamed mucosa, IL-8 and TNF-alpha mRNA expressions were high compared with NCC. Both IL-6 and IL-8 mRNAs decreased to normal levels after granulocytapheresis.

CONCLUSIONS

During active UC, all 4 cytokine mRNA levels were high; only IL-6 and IL-8 mRNAs decreased to normal levels during remission. IL-8 mRNA was high even at sites of endoscopically quiescent UC during active disease. Steroid naïve patients respond well to granulocytapheresis.

Negative feedback regulation of colitogenic CD4+ T cells by increased granulopoiesis

BACKGROUND

Chronic inflammatory diseases are characterized by massive infiltration of innate and acquired immune cells in inflammatory sites. However, it remains unclear how these cells cooperate in the development of disease. Although bone marrow (BM) is a primary site for hematopoiesis of immune cells except T cells, BM recruits memory T cells from the periphery. We have recently demonstrated that colitogenic CD4(+) memory T cells reside in BM of colitic CD4(+)CD45RB(high) T-cell-transferred SCID mice. Based on this background we here investigate whether granulocytes promote or suppress the expansion of colitogenic CD4(+) T cells.

METHODS

First, we show that Gr-1(high)CD11b(+) granulocytes were significantly increased in colitic BM along with a significant increase of peripheral granulocytes. Consistently, the colony-forming unit (CFU) assay revealed that granulocyte colony formation was dominantly induced by supernatants from anti-CD3-stimulated colitic BM CD4(+) T cells.

RESULTS

Administration of granulocyte-depleting anti-Gr-1 mAb to colitic mice did not ameliorate the colitis, but exacerbated the wasting disease with an increased expansion of systemic, but not lamina propria, CD4(+) T cells with activated phenotype.

CONCLUSIONS

These results suggest that the increased granulopoiesis by colitogenic BM CD4(+) T cells represent a negative feedback mechanism to control systemic inflammation.

New Insights into the Biological and Clinical Significance of Fecal Calprotectin in Inflammatory Bowel Disease

Nowadays, calprotectin, a cytoplasmatic protein, released by activated neutrophilic polymorphonuclear cells (PMN) and/or monocytes-macrophages (MØ), is considered a good indicator of inflammation in several diseases. Accordingly, fecal calprotectin represents a good predictor of clinical relapse in ulcerative colitis (UC) patients, whereas conflicting results have been reported in Crohn's disease (CD) patients. In our study, in 76 IBD patients (29 CD and 47 UC) fecal calprotectin has been evaluated by a commercial ELISA kit. Results demonstrate that levels of this protein in the stool are significantly more elevated in active CD and UC patients than in normal volunteers. In quiescent CD and UC a trend to higher levels of calprotectin than in the normal counterpart is, however, evident. These data suggest that a low-grade inflammation of the intestinal wall is always present in CD and UC patients, which may predict a clinical relapse risk. In the same group of patients calprotectin levels also were analyzed according to sex and age. A trend to higher values of calprotectin was present in male patients with active or quiescent CD than in their female counterparts. Only in UC patients in remission a trend to calprotectin increase was more marked in the male group than in the female counterpart. When CD and UC patients were divided up according to age, calprotectin positivity peaked between 30-39 years in active CD patients, while in quiescent CD maximum positivity was between 40 and 49 years. However, in both active and quiescent UC patients, calprotectin positivity increased with age. The more precocious detectability of fecal calprotectin in CD patients, as a marker of intestinal mucosa inflammation, may be related to the different histopathology of the two diseases (CD versus UC). However, reduced PMN and/or MØ trafficking from peripheral blood to intestinal mucosa with age by effects of chronic treatment should not be ignored in CD patients.

Accumulation, activation, and survival of neutrophils in ulcerative colitis: regulation by locally produced factors in the colon and impact of steroid treatment

BACKGROUND AND AIMS

Neutrophil granulocytes infiltrate the intestinal mucosa in active ulcerative colitis (UC), and may contribute to tissue damage and inflammation. The aim of this investigation was to study the importance of locally produced factors and the impact of steroid treatment on neutrophil functions in UC.

PATIENTS AND METHODS

Intestinal perfusion fluids from 11 patients with active distal UC before and after seven and 28 days of treatment with prednisolone and from seven control patients were used in the study. Neutrophil migration towards perfusion fluid was measured in a microchemotaxis chamber. The effect of perfusion fluids on neutrophil activation was assessed as the surface expression of CD66b by flow cytometry. Neutrophil survival was evaluated by staining with propidium iodide, annexin V, and fluorescein di-acetate. We also assessed the viability of freshly isolated tissue neutrophils from rectal biopsy samples.

RESULTS

Perfusion fluids from untreated patients caused increased migration, activation, and survival of neutrophils. Perfusion fluids collected after treatment had no effect on neutrophil migration, but some of the activation and anti-apoptotic effects remained after 7 days. Anti-granulocyte-macrophage colony-stimulating factor (GM-CSF) inhibited the anti-apoptotic effect of perfusion fluids. Rectal tissue neutrophils from patients with active proctitis had increased viability compared to patients with inactive proctitis and control subjects.

CONCLUSIONS

These data show that mediators in the colon of patients with active UC stimulate the migration, activation, and survival of neutrophils. The activities were partly neutralized by topical steroid treatment. We also identified GM-CSF as an anti-apoptotic factor for neutrophils in inflamed colon.

In patients with ulcerative colitis, adsorptive depletion of granulocytes and monocytes impacts mucosal level of neutrophils and clinically is most effective in steroid naïve patients

BACKGROUND

The aetiology of ulcerative colitis is inadequately understood, and drug therapy has been empirical rather than based on sound understanding of disease aetiology. This has been a major factor for refractoriness and adverse drug effects as additional complications. However, ulcerative colitis by its very nature is exacerbated and perpetuated by inflammatory cytokines, which are released by peripheral granulocytes and monocytes as well. Additionally, active ulcerative colitis is often associated with elevated peripheral granulocytes and monocytes with activation behaviour and are found in vast numbers within the colonic mucosa. Hence, from the clinicopathologic viewpoint, granulocytes and monocytes are appropriate targets for therapy in ulcerative colitis. Based on this thinking, an Adacolumn has been developed for depleting excess granulocytes and monocytes by adsorption.

METHODS

By colonoscopy, biopsy and histology, we investigated the impact of granulocyte and monocyte adsorption (GMA) on the mucosal level of granulocytes and monocytes in patients with active ulcerative colitis. Forty-five patients (26 steroid naïve and 19 steroid-dependent), mean age 44.7 yr, were included. Twenty patients had total colitis and 25 had left-sided colitis. Each patient was given up to 11 GMA sessions over 12 weeks. No patient received additional medications within 4 weeks (steroid) to 8 weeks (other immunosuppressants) prior to entry or during the GMA course. Colonoscopy together with biopsy was done at entry and within 2 weeks after the last GMA session.

RESULTS

At entry, the mean clinical activity index was 12.6; range 10-16. A total of 400 colonic biopsies were examined, which revealed massive infiltration of the colonic mucosa by granulocytes, and GMA was associated with striking reduction of granulocytes in the mucosa. At week 12, 33 of 45 patients (73.3%, P<0.01) had achieved clinical remission (the mean clinical activity index

CONCLUSIONS

This is the first report showing a striking difference in clinical response to GMA between steroid naïve and steroid-dependent patients. Further, patients with deep colonic ulcers together with extensive loss of the mucosal tissue are not like to respond to GMA.

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Key Words Collapse

MESH Headings

• Adult
• Biopsy, Needle
• Cohort Studies
• Colitis, Ulcerative/diagnosis
• Colitis, Ulcerative/immunology
• Colitis, Ulcerative/mortality
• Colitis, Ulcerative/therapy
• Colonoscopy
• Cytokines/immunology
• Cytokines/metabolism
• Female
• Follow-Up Studies
• Granulocytes/immunology
• Granulocytes/metabolism
• Humans
• Immunohistochemistry
• Intestinal Mucosa/immunology
• Intestinal Mucosa/pathology
• Leukapheresis/methods
• Male
• Middle Aged
• Monocytes/immunology
• Monocytes/metabolism
• Probability
• Risk Assessment
• Sensitivity and Specificity
• Severity of Illness Index
• Steroids/therapeutic use
• Survival Rate
• Treatment Outcome

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Grants Collapse

Affiliation(s)

T Tanaka Internal Medicine, Chugoku Rosai Hospital, Hirotagaya 1-5-1, Kure, Hiroshima 737-0193, Japan.
H Okanobu
S Yoshimi
E Murakami
A Kogame
H Imagawa
Y Numata
Y Kuga
T Moriya
T Ohya
G Kajiyama

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IL-6 regulates neutrophil trafficking during acute inflammation via STAT3

The successful resolution of inflammation is dependent upon the coordinated transition from the initial recruitment of neutrophils to a more sustained population of mononuclear cells. IL-6, which signals via the common receptor subunit gp130, represents a crucial checkpoint regulator of neutrophil trafficking during the inflammatory response by orchestrating chemokine production and leukocyte apoptosis. However, the relative contribution of specific IL-6-dependent signaling pathways to these processes remains unresolved. To define the receptor-mediated signaling events responsible for IL-6-driven neutrophil trafficking, we used a series of gp130 knockin mutant mice displaying altered IL-6-signaling capacities in an experimental model of acute peritoneal inflammation. Hyperactivation of STAT1 and STAT3 in gp130(Y757F/Y757F) mice led to a more rapid clearance of neutrophils, and this coincided with a pronounced down-modulation in production of the neutrophil-attracting chemokine CXCL1/KC. By contrast, the proportion of apoptotic neutrophils in the inflammatory infiltrate remained unaffected. In gp130(Y757F/Y757F) mice lacking IL-6, neutrophil trafficking and CXCL1/KC levels were normal, and this corresponded with a reduction in the level of STAT1/3 activity. Furthermore, monoallelic ablation of Stat3 in gp130(Y757F/Y757F) mice specifically reduced STAT3 activity and corrected both the rapid clearance of neutrophils and impaired CXCL1/KC production. Conversely, genetic deletion of Stat1 in gp130(Y757F/Y757F) mice failed to rescue the altered responses observed in gp130(Y757F/Y757F) mice. Collectively, these data genetically define that IL-6-driven signaling via STAT3, but not STAT1, limits the inflammatory recruitment of neutrophils, and therefore represents a critical event for the termination of the innate immune response.

Apoptosis and Bax, Bcl-2, Mcl-1 expression in neutrophils of Crohn's disease patients

BACKGROUND

The etiology of Crohn's disease (CD) remains unknown, and the defective function of neutrophils appears to be associated with this pathology. Neutrophils undergo spontaneous apoptosis which, if not tightly regulated, can induce the development of chronic inflammatory disease. The Bcl-2 protein family is also involved in the regulation of neutrophil apoptosis.

METHODS

This study investigated the apoptosis and expression of some regulatory factors in CD patient and control polymorphonuclear neutrophils (PMN) in suspension and in adhesion on fibronectin, an extracellular matrix protein. These 2 conditions mimic circulating neutrophils before they are recruited at the intestinal levels, and their adhesion to tissue.

RESULTS

Apoptosis in CD patient PMN was delayed in suspension and accelerated in adhesion, which is the opposite of what happens in controls. Higher levels of Bax, Bcl-2, and Mcl-1 proteins were registered in freshly isolated CD patient PMN, in contrast to controls, in which Bcl-2 protein was undetectable. Among the studied pro- and antiapoptotic factors, Bax levels seem to be mainly related to the difference in apoptosis between PMN of CD patients and controls.

CONCLUSIONS

For the first time it has been demonstrated by direct experimental evidence that apoptosis in CD patient PMN is regulated differently from that of control PMN. Abnormal expression of regulating apoptosis proteins is shown in CD patient PMN. These data suggest that the defective functionality of neutrophils can be the early event responsible for the altered mucosal immune response in CD, and that neutrophil apoptosis may offer a new target for specific drugs and therapy tools.

Intensive granulocyte and monocyte adsorption versus intravenous prednisolone in patients with severe ulcerative colitis: an unblinded randomised multi-centre controlled study

BACKGROUND AND AIM

Several uncontrolled studies have reported on the efficacy of adsorptive depletion of peripheral blood granulocytes and monocytes/macrophages (GM) in patients with moderate or severe ulcerative colitis. This study was to compare the efficacy and safety of intensive GMA with intensive intravenous prednisolone in patients with severe ulcerative colitis.

METHODS

Seventy patients with clinical activity index 10-23 were randomly assigned to intensive GMA with the Adacolumn, at 2 sessions/week in the first 3 weeks and then 1 session/week for up to 11 sessions (n = 35) or intravenous prednisolone, 40-60 mg/day for 5-10 days (n = 35). No patient received immunomodulators within 8 weeks prior to entry. Clinical response based on intention to treat was assessed at weeks 2, 6 and 12.

RESULTS

Four patients in the prednisolone group and two patients in the GMA group discontinued in week 1. At weeks 2, 6 and 12, the remission (clinical activity index < or = 4) rates (%) in the GMA group were 17.1, 54.4, 74.3, respectively. The corresponding values in the prednisolone group were 25.7, 51.4 and 48.6. Further, at week 12, 27 patients (77%) in the GMA group and 5 patients (14%) in the prednisolone group were steroid free (P = 0.0076). In the GMA group, flushing and light-headedness were observed in 5 patients versus typical steroid side effects in 29 patients of the prednisolone group.

CONCLUSIONS

In this clinical response to GMA was comparable or better than prednisolone. Further, the response to GMA was slower than to intravenous prednisolone, but was more sustainable than the latter.

Adsorptive depletion of elevated proinflammatory CD14+CD16+DR++ monocytes in patients with inflammatory bowel disease

BACKGROUND

In human blood, two monocyte populations exist, CD14(++)CD16(-) classical monocytes and CD14(+)CD16(+) proinflammatory monocytes, which account for about 10% of total monocytes, but can expand to promote inflammatory conditions. CD14(+)CD16(+) monocytes produce large amounts of inflammatory cytokines including TNF-alpha and IL-1. Adacolumn adsorptive carriers adsorb from the blood in the column most of the monocytes/macrophages and granulocytes and this has been associated with clinical efficacy in patients with active inflammatory bowel disease (IBD). This study was to investigate the CD14(+)CD16(+) monocyte profile in patients with IBD and the impact of Adacolumn on this proinflammatory phenotype.

METHODS

A total of 58 patients with ulcerative colitis (UC, N = 37) or Crohn's disease (CD, N = 21) together with 11 healthy controls were included in this study. Peripheral blood CD14(+)CD16(+) monocytes were determined by three-color immunofluorescence and flow cytometry.

RESULTS

The percentage of CD14(+)CD16(+) monocytes in patients with active CD was significantly (P= 0.0089) higher than the level in the control group, in patients with quiescent CD (P= 0.0419) or quiescent UC (P= 0.0063). Further, the percentage of CD14(+)CD16(+) monocytes in patients with active UC who were on prednisolone (PSL) was less than the level in those not on PSL (P < 0.0001), thus PSL might have a suppressive effect on CD14(+)CD16(+) monocytes. Patients with active IBD were each given up to 10 Adacolumn granulocye/monocyte adsorption (GMA) sessions over an 8-wk period. The percentage of CD14(+)CD16(+) monocytes decreased dramatically (P= 0.0077 in UC and P= 0.0117 in CD) compared with entry levels.

CONCLUSIONS

A significant reduction in peripheral CD14(+)CD16(+) monocytes by GMA should mitigate the inflammatory drive and contribute to the clinical efficacy of this procedure. Reduction of CD14(+)CD16(+) monocytes by corticosteroids was also seen. Hence, corticosteroids should enhance the efficacy of GMA. This is the first report on CD14(+)CD16(+) monocytes being decreased by Adacolumn GMA in patients with IBD.

Cytapheresis as a Non-Pharmacological Therapy for Inflammatory Bowel Disease

SUMMARY: Although inflammatory bowel disease (IBD), including ulcerative colitis (UC) and Crohn's disease (CD), is a chronic recurrent disease with unknown etiology. Recent immunological studies suggest close relation to autoimmune status featured by antibodies against colonic epithelial cells. For patients with IBD, 5-aminosalycilates are often used in case of mild disease, and corticosteroids are standard therapy for moderate-to-severe disease. However, we often encounter patients who are resistant to or dependent of conventional therapy, which are likely to lead to future problems in quality of life due to adverse effects of drugs used, especially corticosteroids. Extracorporeal leukocyte removal therapy (cytapheresis) is one of the adjunctive therapies for IBD patients refractory to steroids. By removing circulating activated leukocytes, especially granulocytes and lymphocytes, impaired immune response is suppressed. In the present article recently published studies are reviewed in order to reflect the current state of the art in the use of cytapheresis for treating IBD, especially UC and CD. Although there are only few randomized controlled trials, clinical experience so far suggests that cytapheresis has superior efficiency than conventional therapies in steroid-resistant moderate-to-severe UC. Moreover, cytapheresis features its safety characteristic compared with other conventional medications for severe UC, cytapheresis is regarded as safe treatment regimen.

Dynamic regulation of neutrophil survival through tyrosine phosphorylation or dephosphorylation of caspase-8

Efficient expression of innate immunity is critically dependent upon the capacity of the neutrophil to be activated rapidly in the face of an acute threat and to involute once that threat has been eliminated. Here we report a novel mechanism regulating neutrophil survival dynamically through the tyrosine phosphorylation or dephosphorylation of caspase-8. Caspase-8 is tyrosine-phosphorylated in freshly isolated neutrophils but spontaneously dephosphorylates in culture, in association with the progression of constitutive apoptosis. Phosphorylation of caspase-8 on Tyr-310 facilitates its interaction with the Src-homology domain 2 containing tyrosine phosphatase-1 (SHP-1) and enables SHP-1 to dephosphorylate caspase-8, permitting apoptosis to proceed. The non-receptor tyrosine kinase, Lyn, can phosphorylate caspase-8 on Tyr-397 and Tyr-465, rendering it resistant to activational cleavage and inhibiting apoptosis. Exposure to lipopolysaccharide reduces SHP-1 activity and binding to caspase-8, caspase-8 activity, and rates of spontaneous apoptosis. SHP-1 activity is reduced and Lyn increased in neutrophils from patients with sepsis, in association with profoundly delayed apoptosis; inhibition of Lyn can partially reverse this delay. Thus the phosphorylation and dephosphorylation of caspase-8, mediated by Lyn and SHP-1, respectively, represents a novel, dynamic post-translational mechanism for the regulation of neutrophil apoptosis whose dysregulation contributes to persistent neutrophil survival in sepsis.

Aggravation of different types of experimental colitis by depletion or adhesion blockade of neutrophils

BACKGROUND & AIMS

Neutrophils are generally thought to play an important proinflammatory role in the pathogenesis of inflammatory bowel disease. The objective of this study was to evaluate whether blocking the invasion of neutrophils by anti-L-selectin monoclonal antibodies modulates chemically induced colitis and how this modulation is accomplished.

METHODS

Trinitrobenzene sulfonic acid/dinitrobenzene sulfonic acid (TNBS/DNBS)-induced colitis was studied in rats on treatment with anti-L-selectin monoclonal antibodies (mAb) or antineutrophil antiserum. Different anti-L-selectin mAb, either blocking or nonblocking, as well as F(ab)(2) fragments were evaluated. Additionally, leukocyte migration was examined using intravital microscopy. Furthermore, the effect of neutrophil depletion in rat TNBS-induced colitis was studied either prior to or after colitis induction as well as murine CD4(+)CD45RB(high) transfer colitis. Finally, bacterial translocation during DNBS-induced colitis was studied in neutrophil-depleted and control rats.

RESULTS

Anti-L-selectin mAb treatment resulted in increased mortality and bowel inflammation as well as hemorrhagic eye secretion. No clear difference was found between blocking and nonblocking mAb or F(ab)(2) fragments. For all investigated antibodies/fragments, either complete blockade of leukocyte invasion or marked neutrophil depletion was found. Accordingly, neutrophil depletion by antiserum resulted in aggravation of rat DNBS-induced colitis as well as murine transfer colitis.

CONCLUSIONS

Adhesion blockade or neutrophil depletion aggravates rat TNBS/DNBS-induced colitis together with extraintestinal manifestations of the eyes. Therefore, neutrophils appear to have an important role in mucosal repair processes. Importantly, adhesion blockade as a therapeutic concept can be detrimental in inflammatory bowel disease.

Therapeutic leukocytapheresis for inflammatory bowel disease

The inference that granulocytes and monocytes/macrophages (GM) are part of the immunopathogenesis of inflammatory bowel disease (IBD) and hence should be targets of therapy stems from observations of elevated, and activated GM in patients with IBD. The Adacolumn can selectively deplete GM by adsorption (GMA) and in patients with IBD, GMA has been associated with significant clinical efficacy together with sustained suppression of inflammatory cytokine profiles. Additionally, GMA depleted proinflammatory CD14(+)CD16(+) monocytes and was followed by an increase in CD4(+) T lymphocytes including the regulatory CD4(+)CD25(high+)Foxp3 phenotype. Hence, GMA could be a non-pharmacologic therapy for IBD with potential to spare steroids and other unsafe pharmacologic preparations.

Demonstration of low-regulatory CD25High+CD4+ and high-pro-inflammatory CD28-CD4+ T-Cell subsets in patients with ulcerative colitis: modified by selective granulocyte and monocyte adsorption apheresis

Low-CD25(High+)CD4(+), a subset of regulatory CD25(+)CD4(+) T cells and high-inflammatory CD28(-)CD4(+) T cells can exacerbate ulcerative colitis (UC). This study sought to investigate the frequency of CD25(High+)CD4(+) and CD28(-)CD4(+) T cells in patients with UC and the changes in these cells during Adacolumn granulocyte and monocyte adsorption apheresis (GMA). Subjects were 12 patients with active UC, 11 with quiescent UC, and 14 healthy volunteers (HVs). The mean clinical activity index was 15.7 +/- 2.2 in active UC and 4.5 +/- 1.1 in quiescent UC. Peripheral blood samples were stained with CD4, CD25, and CD28 antibodies for flow cytometry. Patients with active UC received GMA and blood samples were examined before and after the first GMA session. Patients with active UC (P < 0.04) or quiescent UC (P < 0.02) had a higher percentage of CD28(-)D4(+)T cells compared with HVs, while the percentage of CD28(+)CD4(+) T cells was lower in both UC groups compared with HVs (P = 0.03 and P < 0.02). Patients with active UC had a lower percentage of CD25(High+)CD4(+)T cells compared with quiescent UC patients (P < 0.001). A significant increase in CD25(High+)CD4(+) T cells was associated with GMA (P < 0.03). Low CD25(High+)CD4(+) and high CD28(-)CD4(+) are prominent features in UC. The increase in CD25(High+)CD4(+) T cells induced by GMA should contribute to improved immune function. Additional studies are warranted, since a low frequency of CD25(High+)CD4(+) (-) and a high frequency of CD28(-)CD4(+) (-) expressing T cells might be a predictor of clinical response to GMA.

The immune response in inflammatory bowel disease

Ulcerative colitis (UC) and Crohn's disease (CD), collectively referred to as inflammatory bowel disease (IBD), present with differing histologic and cytokine profiles. While the precise mechanisms underlying the development of IBD are not known, sufficient data have been collected to suggest that it results from a complex interplay of genetic, environmental, and immunologic factors. Animal models of colitis, along with a more detailed understanding of the immune response in the normal bowel, have led to unifying hypotheses regarding the pathogenesis. An inappropriate mucosal immune response to normal intestinal constituents is a key feature, leading to an imbalance in local pro- and anti-inflammatory cytokines. Neutrophil and monocyte influx occurs with subsequent secretion of oxygen radicals and enzymes, leading to tissue damage. Therapy of IBD has improved and expanded as the understanding of disease mechanisms has evolved. Pharmacologic agents such as aminosalicylates, azathioprine/6-mercaptopurine, or steroids are the mainstays of therapy. Newer agents including monoclonal antibodies targeted to specific proinflammatory cytokines, such as tumor necrosis factor-alpha (TNF-alpha), have emerged and provide great clinical benefit, but unknown long-term toxicity and immunogenicity may limit their use.

Factors affecting clinical and endoscopic efficacies of selective leucocytapheresis for ulcerative colitis

BACKGROUND

Granulocyte, monocyte/macrophage adsorptive apheresis is a novel treatment for active ulcerative colitis. However, as yet no study has reported on a subset of patients who might respond well to granulocyte, monocyte/macrophage adsorptive apheresis therapy.

AIM

To identify factors affecting clinical and endoscopic efficacies of granulocyte, monocyte/macrophage in patients with ulcerative colitis.

METHODS

Fifty consecutive patients with active ulcerative colitis initially received five granulocyte, monocyte/macrophage adsorptive apheresis sessions with the Adacolumn over five consecutive weeks. Patients who improved without achieving remission received five additional granulocyte, monocyte/macrophage adsorptive apheresis sessions.

RESULTS

One week after the last granulocyte, monocyte/macrophage adsorptive apheresis session, 26 (52%) and 17 patients (34%) achieved clinical and endoscopic remission, respectively. In the multivariate analysis, the dose of prednisolone administered at entry and the cumulative dose of prednisolone administered before entry were independent significant factors for both clinical and endoscopic remission, negatively impacted the efficacy of granulocyte, monocyte/macrophage adsorptive apheresis. Age, gender, duration of ulcerative colitis, number of prior relapses, duration of current exacerbation, extent and severity of ulcerative colitis, extra-intestinal manifestations, entry haematology values and C-reactive protein did not affect the outcome.

CONCLUSIONS

Based on the outcomes of this study, it appears that steroid-naïve patients and patients on low dose steroid and short duration of exposure respond to granulocyte, monocyte/macrophage adsorptive apheresis. Further studies in larger cohorts of patients should strengthen our findings.

Adacolumn selective leukocyte adsorption apheresis in patients with active ulcerative colitis: clinical efficacy, effects on plasma IL-8, and expression of Toll-like receptor 2 on granulocytes

Adacolumn selective granulocyte and monocyte apheresis (GMA) depletes activated leukocytes in patients with ulcerative colitis (UC). However, this per se cannot fully explain the efficacy of GMA. We have investigated the effects of GMA on the expression of toll-like receptors (TLRs) and plasma interleukin-8 (IL-8). Twenty-two patients with clinical activity index (CAI) of 5-17, 15 with total colitis and 7 with left-sided colitis, were included. Each patient could receive up to 10 GMA sessions, at 1 or 2 sessions per week. GMA was added to the patients' ongoing medication following a relapse or worsening UC, but no additional medication was given. Further, at entry and pre-GMA, blood samples were taken for full blood cell count, expression of TLRs on leukocytes, and plasma IL-8. Seventy-five percent of patients achieved remission after the 10th session (CAI, < or =4; P < 0.005) and there was a marked fall in C-reactive protein (P < 0.01), plasma IL-8 (P < 0.001), and granulocytes (P < 0.05) but an increase in lymphocytes (P < 0.05). The expression of TLR2 on granulocytes was down-modulated (P < 0.05) together with suppression of inflammatory cytokines produced by peripheral blood leukocytes. In conclusion, GMA appears to be an effective adjunct therapy to induce remission in the majority of patients, who are then spared from excess drug therapy. The procedure is associated with sustained immunomodulation. Control studies should strengthen these findings.

Mutations in the cofilin partner Aip1/Wdr1 cause autoinflammatory disease and macrothrombocytopenia

A pivotal mediator of actin dynamics is the protein cofilin, which promotes filament severing and depolymerization, facilitating the breakdown of existing filaments, and the enhancement of filament growth from newly created barbed ends. It does so in concert with actin interacting protein 1 (Aip1), which serves to accelerate cofilin's activity. While progress has been made in understanding its biochemical functions, the physiologic processes the cofilin/Aip1 complex regulates, particularly in higher organisms, are yet to be determined. We have generated an allelic series for WD40 repeat protein 1 (Wdr1), the mammalian homolog of Aip1, and report that reductions in Wdr1 function produce a dramatic phenotype gradient. While severe loss of function at the Wdr1 locus causes embryonic lethality, macrothrombocytopenia and autoinflammatory disease develop in mice carrying hypomorphic alleles. Macrothrombocytopenia is the result of megakaryocyte maturation defects, which lead to a failure of normal platelet shedding. Autoinflammatory disease, which is bone marrow-derived yet nonlymphoid in origin, is characterized by a massive infiltration of neutrophils into inflammatory lesions. Cytoskeletal responses are impaired in Wdr1 mutant neutrophils. These studies establish an essential requirement for Wdr1 in megakaryocytes and neutrophils, indicating that cofilin-mediated actin dynamics are critically important to the development and function of both cell types.

Electroacupuncture and moxibustion promote neutrophil apoptosis and improve ulcerative colitis in rats

The purpose of this study was to investigate the effect of electroacupuncture (EA) and moxibustion on promoting neutrophil apoptosis. A rat model of ulcerative colitis was established by immunological methods using human colonic mucosa as antigen. All rats were randomly assigned to the model control (MC) group, EA group, or herbs-partition moxibustion (HPM) group. Normal rats were used as the normal control (NC) group. Peripheral blood mononuclear cells (PBMCs) from all rats and circular neutrophils from NC rats were isolated and cultured. Circular neutrophils were incubated with cultured supernatants of PBMCs from the MC, NC, EA, and HPM groups, respectively. Neutrophil apoptosis and concentration of IL-1beta, IL-6, and TNF-alpha from induced cultured supernatants were detected by cell cytometry and ELISA, respectively. Compared with MC, HPM, and EA rats, mucosal inflammatory lesions abated remarkably. No hyperemia or edema was seen in the lamina propria, inflammatory cell infiltration decreased, neutrophil infiltration disappeared, and epithelial and crypt cells proliferated and repaired the ulceration of the mucosa. Neutrophil apoptosis was promoted. Concentrations of IL-1beta, IL-6, and TNF-alpha were decreased, respectively. We conclude that EA and HPM therapy can improve ulcerative colitis rats histologically, which may be due to promoting neutrophil apoptosis and down-regulating monocyte cytokines. EA and moxibustion are effective for treating ulcerative colitis.

Positions of selective leukocytapheresis in the medical therapy of ulcerative colitis

Ulcerative colitis (UC) and Crohn’s disease (CD) are the major forms of idiopathic inflammatory bowel disease (IBD). Both UC and CD are debilitating chronic disorders that afflict millions of individuals throughout the world with symptoms which impair function and quality of life. The etiology of IBD is inadequately understood and therefore, drug therapy has been empirical instead of being based on sound understanding of IBD pathogenesis. This is a major factor for poor drug efficacy and drug related side effects that often add to the disease complexity. The development of biologicals notably infliximab to intercept tumor necrosis factor (TNF)-α reflects some progress, albeit major concern about their side effects and lack of long-term safety and efficacy profiles. However, IBD seems to be perpetuated by inflammatory cytokines like TNF-α, interleukin (IL)-1β, IL-6 and IL-8 for which activated peripheral granulocytes and monocytes/macrophages (GM) are major sources. Further, in IBD, peripheral GMs are elevated with activation behavior, increased survival time and are found in vast numbers within the inflamed intestinal mucosa; they are suspected to be major factors in the immunopathogenesis of IBD. Hence, peripheral blood GMs should be appropriate targets of therapy. The Adacolumn is a medical device developed for selective depletion of GM by receptor-mediated adsorption (GMA). Clinical data show GMA, in patients with steroid dependent or steroid refractory UC, is associated with up to 85% efficacy and tapering or discontinuation of steroids, while in steroid naïve patients (the best responders), GMA spares patients from exposure to steroids. Likewise, GMA at appropriate intervals in patients at a high risk of clinical relapse suppresses relapse thus sparing the patients from the morbidity associated with IBD relapse. Further, GMA appears to reduce the number of patients being submitted to colectomy or exposure to unsafe immunosupressants. First UC episode, steroid naivety and short disease duration appear good predictors of response to GMA and based on the available data, GMA seems to have an excellent safety profile.

Loss of fragile histidine triad protein expression in inflammatory bowel disease

AIM: To investigate the expression of fragile histidine triad (FHIT) protein in 64 patients with ulcerative colitis (UC) and Crohn’s disease (CD), and its relation with clinicopathological data.

METHODS: Rabbit-anti-FHIT antibody was used to detect FHIT protein expression in 64 formalin-fixed, paraffin-embedded tissue specimens of inflammatory bowel disease (IBD) by citrate-microwave-streptavidin (SP)-HRP immunohistochemical method.

RESULTS: The positive FHIT protein expression was 22.79% ± 16.16%, 42.14% ± 16.82% in active and remittent phases of UC, 36.07% ± 19.23% in CD, and 57.05% ± 8.86% in normal colon mucosa. Statistically significant differences in FHIT protein expression were observed between the active and remittent phases of UC, between the active phase of UC and normal colon mucosa, as well as between the remittent phase of UC and normal colon mucosa, and between CD and normal colon mucosa.

CONCLUSION: Our results show that FHIT protein expression is completely absent or reduced in IBD, suggesting that the FHIT gene might be associated with the oncogenesis and progression of IBD, an early event from inflammatory conditions to carcinoma in IBD.

A retrospective search for predictors of clinical response to selective granulocyte and monocyte apheresis in patients with ulcerative colitis

Recently, selective granulocytapheresis (Adacolumn) has appeared as a new treatment for patients with inflammatory bowel disease. This study sought to determine predictors of response to this new nonpharmacologic mode of therapy by retrospectively evaluating 28 patients who received granulocytapheresis after experiencing active ulcerative colitis (UC). Between April 2000 and March 2004, 28 consecutive patients received granulocytapheresis for active UC with the Adacolumn, which is filled with cellulose acetate beads as the column leukocytapheresis carriers; the carriers adsorb granulocytes, monocytes/macrophages, and a small fraction of lymphocytes (FcgammaR and complement receptors bearing leukocytes). Each patient could receive up to 10 Adacolumn sessions, at 2 sessions per week. In 2004, clinical response was retrospectively evaluated. Seven days after the last Adacolumn session, 20 of 28 patients had remission (colitis activity index [CAI] < or =4) including all 8 patients who had their first UC episode. The mean duration of UC in the 8 first episode cases was 3.4 months compared with 40.2 months for all 28 patients and 65.4 months for the 8 nonresponders. The response to Adacolumn was independent of basal CAI. The 8 nonresponders were given conventional medication (CM) or cyclosporine (CsA) if the former failed. Two responded to CM, 3 to CsA, and 3 underwent colectomy. First UC episode and short disease duration appear good predictors of response to granulocytapheresis. Selective granulocytapheresis might be an effective first-line treatment.

Down-regulation of interferon-gamma parallels clinical response to selective leukocyte apheresis in patients with inflammatory bowel disease: a 12-month follow-up study

BACKGROUND & AIMS

Pilot studies have indicated a therapeutic role for an apheresis device (Adacolumn) that selectively adsorbs leukocytes in patients with inflammatory bowel diseases. It may also exert immunoregulatory effects contributing to its clinical efficacy. This study aimed to correlate the clinical response to leukocyte apheresis with the expression of key cytokines in mucosal tissue, in peripheral leukocytes, and in plasma.

METHODS

Ten patients (seven with Crohn's disease and three with ulcerative colitis, median age: 31 years) with mild to moderately chronic activity were recruited to an open study. Patients were refractory to or had a relapse despite conventional treatment including azathioprine. Leukocyte apheresis was performed once a week for five consecutive weeks. Clinical efficacy was assessed on week 7 and after 12 months. Colonoscopy with multiple biopsies was performed at the start of the study and after 7 weeks for semiquantitative immunohistochemical analyses of cytokines. Cytokine levels in blood and the proportion of cytokine producing CD4+ and CD8+ lymphocytes were determined.

RESULTS

The apheresis procedures were well tolerated and no major adverse events were encountered. The median clinical activity score decreased from 12 to 7 on week 7 (P=0.031, n=9) and to 4 after 12 months (P=0.004, n=9). Five patients were in clinical remission at the 12th month. Tissue interferon (IFN)-gamma-positive T-cells decreased in clinical responders (P=0.027) after apheresis. In parallel, significantly lower levels of IFN-gamma-producing lymphocytes were detected in peripheral blood. IFN-gamma-positive cells in pretreatment biopsies completely disappeared or decreased in posttreatment biopsies sampled on week 7 in responders (P=0.027) and appeared to predict the maintenance of long-term remission or response after 12 months.

CONCLUSIONS

Leukocyte apheresis is a novel and safe nonpharmacological adjunct therapy that may prove useful in steroid refractory or dependent patients when conventional drugs have failed. Down-regulation of IFN-gamma in mucosal biopsies and in peripheral leukocytes may be a predictive marker for sustained, long-term response.