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

Crohn's disease complicated by hepatitis B virus successfully treated with the use of adsorptive depletion of myeloid lineage leucocytes to suppress inflammatory cytokine profile

BACKGROUND AIMS

In patients with inflammatory bowel disease infected with hepatitis B virus (HBV), immunosuppressive therapy required to suppress active inflammatory bowel disease may promote HBV reactivation.

METHODS

A 27-year-old corticosteroid-naive woman with Crohn's disease (CD) activity index of 249.8 complicated by HBV infection was offered Entecavir to control HBV reactivation during immunosuppressive therapy for CD. The patient refused Entecavir, fearing that it might adversely affect her pregnancy outcome. Instead, we applied intensive granulocyte/monocyte adsorptive apheresis (GMA) at two sessions per week to deplete inflammatory cytokine-producing leucocytes as an immunosuppressive therapy in this case.

RESULTS

GMA induced stable remission (CD activity index, I 105) and endoscopic improvement without HBV reactivation or safety concern. Furthermore, CD remission was paralleled by suppression of tumor necrosis factor and interleukin as measured in serum samples.

CONCLUSIONS

Immunosuppressive therapy required to treat an active CD potentially can promote HBV reactivation and worsen liver function. In this study involving a CD case complicated by chronic HBV infection, intensive GMA as a non-pharmacologic treatment intervention was associated with clinical remission and endoscopic improvement without HBV reactivation. Furthermore, GMA was well-tolerated and was without any safety concern. However, suppression of tumor necrosis and interleukin-6by GMA in this clinical setting is potentially very interesting.

Naïve T cells correlate with mucosal healing in patients with inflammatory bowel disease

BACKGROUND

In previous studies, adaptive immune responses involving T-helper cells have been shown to play an important role in inflammatory bowel diseases (IBDs).

METHODS

The aim of this study was to investigate any correlation between the degree of mucosal inflammation and the phenotype of gut-infiltrating T-helper cells. Biopsies from intestinal mucosa were obtained and intestinal T cells were analyzed with regard to activity and maturation markers. Patients with active colitis (39 with Crohn's disease and 47 with ulcerative colitis) were included and treated with corticosteroids, biologicals or leukocytapheresis. Flow cytometry was used to analyze activation marker expression on gut-infiltrating T-helper cells.

RESULTS

Mucosal healing was reflected by almost 100% increase of CD62L expression in mucosal T cells in patients in remission compared to those with active inflammation (p < 0.01). The frequency of mucosal-naïve CD4(+)CD45RA(+) T cells was reduced by 50% in mucosa displaying remission (5.3% compared to 12% of the total amount and CD4(+) T cells, p < 0.001). Surprisingly, the proportion of early activated T-helper cells (CD4(+)CD69(+)) did not differ between mucosa in remission and non-remission (43% and 42%, respectively). Moreover, no change in memory T-helper cells (CD4(+)CD45RO(+)) was observed (64% compared to 66%). The findings were independent of diagnosis (Crohn's disease or ulcerative colitis) or mode of treatment.

CONCLUSION

This study suggests that a reduced recruitment of naïve T-helper cells and increased frequency of T-helper cells with lymph node homing marker expression reflect mucosal healing in IBD. Surprisingly, the degree of activation of mucosal T-helper cells did not correlate with disease remission.

Myeloid-derived suppressor cells in the inflammatory bowel diseases

BACKGROUND

Myeloid cells are the most abundant and heterogeneous population of leukocytes. They are rapidly recruited from the blood to areas of inflammation and perform a number of important biological functions. Chronic inflammatory conditions contribute to generation of myeloid-derived suppressor cells (MDSCs). These pathologically activated cells are increasingly recognized as important players in cancer, transplantation, and autoimmunity for their abilities to modulate innate and adaptive immune responses.

METHODS

Since clinical data on MDSC accumulation in human patients affected with inflammatory bowel diseases (IBD) are relatively scarce, most of the information described in this review came from studies using experimental mouse models of IBD.

RESULTS

In this review, we discuss possible roles of these cells in chronic immune-mediated disorders focusing on studies conducted in IBD. We will review the available evidence on how MDSCs are involved in modulating T cell responses and look into the complex relationship between Th1, Th17 cells, and myeloid cells. Finally, we will review some recent successes and failures resulted from therapies aimed at manipulating myeloid cell numbers and/or their function.

CONCLUSIONS

Although MDSCs have been described in animal models of experimental colitis and in patients with IBD, their exact role in IBD pathogenesis is unclear and needs to be studied further. Information obtained from these studies will be useful to better understand the cross talk between myeloid cells in T cells during chronic inflammation and may identify novel pathways to be targeted therapeutically.

The selective therapeutic apheresis procedures

Selective apheresis procedures have been developed to target specific molecules, antibodies, or cellular elements in a variety of diseases. The advantage of the selective apheresis procedures over conventional therapeutic plasmapheresis is preservation of other essential plasma components such as albumin, immunoglobulins, and clotting factors. These procedures are more commonly employed in Europe and Japan, and few are available in the USA. Apheresis procedures discussed in this review include the various technologies available for low-density lipoprotein (LDL) apheresis, double filtration plasmapheresis (DFPP), cryofiltration, immunoadsorption procedures, adsorption resins that process plasma, extracorporeal photopheresis, and leukocyte apheresis.

Treatment of inflammatory bowel disease by chemokine receptor-targeted leukapheresis

Leukapheresis removes circulating leukocytes en route to the target organ. Hitherto unspecific matrixes have been used to remove leukocytes in inflammatory bowel disease (IBD). This report describes a novel selective leukapheresis column based on chemokine-chemokine receptor interaction. We found an increased expression of the gut homing chemokine receptor CCR9 on CD14(+) monocytes and on CD3(+) T lymphocytes from IBD patients. Biologically active CCL25 was coupled to a Sepharose matrix and demonstrated to selectively remove CCR9-expressing cells leaving other cell populations largely unaffected. A patient with active ulcerative colitis, was subjected to CCL25-column leukapheresis. Four days after treatment, he experienced clinical improvement and stable disease improvement ensued. The study illustrates that specific cells can be targeted using high affinity interactions, i.e., CCL25-CCR9 interactions to remove pathogenic gut-homing cells. Leukapheresis using the bCCL25 column should be investigated in a clinical phase I trial of patients with inflammatory bowel disease.

Looking for endoscopic features of cytomegalovirus colitis: a study of 187 patients with active ulcerative colitis, positive and negative for cytomegalovirus

BACKGROUND

Cytomegalovirus (CMV) is frequently detected in ulcerative colitis (UC) lesions of steroid-refractory patients. This has led to the suspicion that CMV might cause colitis and steroid refractoriness.

METHODS

During 2003 and 2011, 187 consecutive patients were divided into group I (n = 105), corticosteroid-free and thiopurine-free in the past 6 months, and group II (n = 82), all corticosteroid refractory. The combination of serum CMV immunoglobulin (Ig)M, CMV IgG, CMV antigenemia (Ag), and real-time polymerase chain reaction assays were performed to identify CMV(+) patients.

RESULTS

In group I, 79 patients were CMV IgG(+) and 26 patients were CMV IgG(-) and CMV IgM(-). In group II, 61 patients were CMV IgG(+), 1 CMV IgM(+), and 20 CMV IgG(-) and CMV IgM(-). All CMV IgG(+) patients were screened for CMV Ag. In group I, 6 of the 79 CMV IgG(+) patients were CMV Ag(+). In group II, 27 patients were CMV Ag(+). Colonoscopy was performed in all patients before screening for CMV. Similar colonoscopic features including punched out ulcers, geographic ulcers, and irregular ulcers were found in both CMV(+) and CMV(-) patients, without any striking difference between the 2 groups.

CONCLUSIONS

CMV reactivation might be encouraged by immunosuppressive drugs, like corticosteroids, immunomodulators, and therefore, patients with UC are at a high risk of CMV reactivation, potentially exacerbating UC. However, this study of 187 patients, CMV(+) and CMV(-), could not find colonoscopic features unique to CMV, except that CMV might be one factor for steroid refractoriness, and UC exacerbation.

Looking for predictive factors of clinical response to adsorptive granulocyte and monocyte apheresis in patients with ulcerative colitis: markers of response to GMA

BACKGROUND

Adsorptive granulocyte and monocyte apheresis (GMA) with an Adacolumn in patients with ulcerative colitis (UC) has been applied as a non-pharmacological treatment strategy, but the efficacy has been encouraging as well as discouraging, depending on patients' demography at entry. In this study, we looked for predictive factors for clinical response to GMA in patients with UC.

METHODS

In a retrospective setting, 43 outpatients who had been treated with GMA for active UC were evaluated. Patients were divided into remission group and non-remission group based on Lichtiger's clinical activity index (CAI) before and after 10, once a week GMA sessions. The efficacy was analysed in relation to patients' demographic variables. To determine predictive factors that closely related to the response to GMA, receiver operating characteristic (ROC) curve, and multiple logistic regression analyses were applied.

RESULTS

After 10 GMA sessions, the overall clinical remission rate (CAI < 4) was 53.5%. Multiple logistic regression and ROC analyses showed that the interval between relapse and the first GMA session was a significant and independent predictive factor for clinical response to GMA (P = 0.016); the clinical response was better in patients who received GMA immediately after a relapse and vice versa. Likewise, univariate analyses showed that, the duration of UC (P = 0.036) and the cumulative prednisolone (PSL) dose (P = 0.006) before the first GMA session were significantly greater in the GMA non-responder group as compared with the responder group. Additionally, a lower white blood cell (WBC) count at first GMA session was related to clinical response to GMA (P = 0.032).

CONCLUSIONS

In this study, patients with a short duration of UC and low cumulative PSL dose seemed to respond well to GMA. However, we found that the best responders were patients who received GMA immediately after a clinical relapse. Additionally, GMA was effective in patients with low WBC count at the first GMA session. The findings of this study should spare medical cost and reduce morbidity time for many patients, relevant for decision making in clinical settings.

Flare up of ulcerative colitis during pregnancy treated by adsorptive granulocyte and monocyte apheresis: therapeutic outcomes in three pregnant patients

PURPOSE

Treatment of ulcerative colitis with drugs during pregnancy potentially may harm the mother and the unborn child. Granulocytapheresis depletes elevated/activated myeloid lineage leucocytes as sources of inflammatory cytokines. We were interested in the safety and efficacy of granulocytapheresis in patients who had ulcerative colitis flare up during pregnancy.

METHODS

Three pregnant cases with active ulcerative colitis received Adacolumn granulocytapheresis, up to 10 sessions within 3-6 weeks. Case 1: a 33-year-old woman with left-sided colitis and bloody diarrhoea 7-9 times/day showed loss of mucosal vascular patterns, and contact bleeding from the rectum to the sigmoid colon. Case 2: a 36-year-old woman with pancolitis and bloody diarrhoea 6-8 times/day had loss of mucosal vascular patterns and pus from the rectum to the sigmoid colon. Case 3: a 36-year-old woman with pancolitis and diarrhoea 4-5 times/day (first episode) had erosions and pus in the mucosa from the rectum to the transverse colon.

RESULTS

Colitis flare was in weeks 5, 13 and 22 of pregnancy in cases 1, 2, 3, respectively. The corresponding granulocytapheresis sessions were 5, 7, and 10, reflecting an increasing trend with the pregnancy week. Patients 1 and 2 achieved complete remission, patient 3 achieved clinical remission.

CONCLUSION

In these three cases with active ulcerative colitis during pregnancy, granulocytapheresis as a non-pharmacologic treatment was effective and safe. In case 3 that did not respond well to the initial granulocytapheresis sessions, a moderate dose of prednisolone enhanced the efficacy of granulocytapheresis and tapering of prednisolone shortly after administration was not associated with relapse.

Therapeutic depletion of myeloid lineage leukocytes in patients with generalized pustular psoriasis indicates a major role for neutrophils in the immunopathogenesis of psoriasis

BACKGROUND

Generalized pustular psoriasis (GPP) is a chronic autoimmune disease characterized by fever, erythema, and neutrophilic pustules over large areas of the skin. GPP does not respond well to pharmacologic intervention.

OBJECTIVE

We sought to assess efficacy of selectively depleting the myeloid lineage leukocytes in patients with GPP.

METHODS

Fifteen patients with persistent moderate to severe GPP despite conventional therapy were included. Eligible patients had more than 10% of their skin area covered by pustules. Treatment with oral etretinate, cyclosporine, methotrexate, prednisolone, and topical prednisolone/vitamin D3 was continued if had been initiated well in advance of study entry. Five sessions of adsorptive granulocyte and monocyte apheresis (GMA) with the Adacolumn (JIMRO Co Ltd, Takasaki, Japan) were administered (1 session/wk over 5 weeks) to selectively deplete Fcγ receptor and complement receptor bearing leukocytes. Efficacy was assessed by measuring the skin areas covered by pustules at baseline and 2 weeks after the last GMA session.

RESULTS

One patient did not complete the first GMA session. Based on the GPP severity scores relative to entry, the overall scores improved (n = 14, P = .0027), and the area of erythroderma (P = .0042), pustules (P = .0031), and edema (P = .0014) decreased. Likewise, Dermatology Life Quality Index improved (P = .0016), reflecting better daily function and quality of life. Twelve patients were judged as responders (85.7%), and 10 patients maintained the clinical response for 10 weeks after the last GMA session without any change in medication.

LIMITATIONS

This study was unblinded and without a placebo arm.

CONCLUSION

GMA in this clinical setting was safe and effective, suggested a major role for granulocytes/monocytes in the immunopathogenesis of GPP.

A new paradigm in ulcerative colitis: regulatory T cells are key factor which induces/exacerbates UC through an immune imbalance

Leukocytapheresis (LCAP) appears to remove or inactivate inflammatory cells and to reset immunological responses, resulting to cure responders of ulcerative colitis (UC). The changes of T cell subsets were investigated in UC patients treated with LCAP. Levels of T cell subsets in peripheral blood before and after LCAP were analysed by flow cytometric analysis. Of 20 UC patients, 13 (65%) achieved remission and 2 (10%) showed the improvement of UC symptoms. Ratios of some T cell subtypes such as regulatory T (Treg) cells and memory T cells to CD4(+) T cells changed significantly only in responders. Especially, ratio of resting Treg/CD4(+) T cells was significantly increased after the first LCAP session, and then one of activated Treg/CD4(+) T cells was increased after 2 week. This may lead to the development of a new UC paradigm in which an imbalance in Treg cell subsets triggers the onset and/or exacerbation of UC.

Steroid-sparing strategies in the management of ulcerative colitis: Efficacy of leukocytapheresis

Active ulcerative colitis (UC) is frequently associated with infiltration of a large number of leukocytes into the bowel mucosa. Leukocytapheresis is a novel nonpharmacologic approach for active UC, in which leukocytes are mechanically removed from the circulatory system. Current data indicate that leukocytapheresis is efficacious in improving response and remission rates with excellent tolerability and safety in patients with UC. Corticosteroid therapy remains a mainstay in the treatment of active UC; however, long-term, high doses of corticosteroids usually produce predictable and potentially serious side effects. If leukocytapheresis can spare patients from exposure to corticosteroids, the risk of steroid-induced adverse events should be minimized. This may be of great benefit to patients because severe side effects of steroids seriously impair health-related quality of life. In this article, we reviewed current evidence on whether leukocytapheresis can avoid or reduce the use of corticosteroids in the management of patients with UC. Several studies have shown that leukocytapheresis was effective for steroid-naïve patients with active UC. Furthermore, both short-term and long-term studies have demonstrated the steroid-sparing effects of leukocytapheresis therapy in patients with UC. Although the evidence level is not striking, the available data suggest that leukocytapheresis can avoid or reduce the use of corticosteroids in the management of UC. Large, well-designed clinical trials are necessary to more accurately evaluate the steroid-sparing effects of leukocytapheresis in the management of UC.

Broadening the translational immunology landscape

It is just over 5 years sinceClinical and Experimental Immunology came under the direction of a new team of Editors and made a concerted effort to refresh its approach to promoting clinical and applied immunology through its pages. There were two major objectives: to foster papers in a field which, at the time, we loosely termed ‘translational immunology’; and to create a forum for the presentation and discussion of immunology that is relevant to clinicians operating in this space. So, how are we doing with these endeavours? This brief paper aims to summarize some of the key learning points and successes and highlight areas in which translational gaps remain.

The efficacy of intensive granulocyte and monocyte adsorption apheresis in a patient with Crohn's disease complicated by extensive subcutaneous aseptic neutrophilic abscesses

BACKGROUND AND AIMS

Subcutaneous aseptic abscess is one phenotype of neutrophilic dermatitis. We were interested to see if a case of steroid refractory Crohn's disease (CD) complicated by subcutaneous aseptic neutrophilic abscesses responds to intensive granulocyte/monocyte adsorptive apheresis (GMA).

METHODS

The patient was a 21-year-old male with worsening severe CD while on oral prednisolone (30 mg/day). His symptoms included fever, bloody diarrhoea and multiple painful subcutaneous nodules throughout his body. Skin biopsy showed chronic panniculitis with neutrophilic infiltrates. Further, colonoscopy showed oedematous sigmoid colon, while colonic biopsy showed non-caseous granuloma. Because biologics were feared to increase the risk of bacteraemia as the result of germ culture on his pus was not known at the time, we decided to treat this case with GMA. Five GMA sessions with the Adacolumn over 5 consecutive days (daily GMA) were initiated.

RESULTS

On admission, his CD activity index (CDAI) was 355, C-reactive protein (CRP) 11.2 mg/dL. After 5 GMA sessions, CDAI decreased to 170, and CRP fell to 5.0 mg/dL, with no fever. GMA was restarted at 2 sessions/week (total 10 sessions). The patient's CDAI fell to <150, and the skin lesions re-epithelialized.

CONCLUSIONS

In this CD case complicated by subcutaneous aseptic neutrophilic abscesses, GMA appeared to be effective. Our impression is that when biopsy reveals neutrophil infiltrate is a major feature of the lesions, GMA should be considered. As GMA appears to have no safety concerns, a frequent GMA protocol, like daily followed by 2 to 3 times/week should be preferred over the routine weekly GMA.

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.

[Inflammatory bowel diseases and inflammasome]

Inflammatory bowel disease (IBD), the most important entities being ulcerative colitis and Crohn's disease, are chronic, relapsing and remitting inflammatory conditions that result from chronic dysregulation of the mucosal immune system in the intestinal tract. Although the precise pathogenesis of IBD is still incompletely understood, increased levels of proinflammatory cytokines, including interleukin (IL)-1b, IL-18 and tumor necrosis factor-a, are detected in active IBD and correlate with the severity of inflammation, indicating that these cytokines may play a key role in the development of IBD. Recently, the intracellular nucleotide-binding oligomerization domain-like receptor (NLR) family members, including NLRP1, NLRP3, NLRC4 and NLRP6, are emerging as important regulators of intestinal homeostasis. Together, one of those aforementioned molecules or the DNA sensor absent in melanoma 2 (AIM2), apoptosis-associated speck-like protein containing 'a caspase recruitment domain (CARD)' (ASC) and caspase-1 form a large (> 700 kDa) multi-protein complex called the inflammasome. Stimulation with specific microbial and endogenous molecules triggers inflammasome assembly and caspase-1 activation. Activated caspase-1 leads to the secretion of proinflammatory cytokines, including IL-1b and IL-18, and the promotion of pyroptosis, a form of phagocyte cell death induced by bacterial pathogens, in an inflamed tissue. Therefore, inflammasomes are assumed to mediate host defense against microbial pathogens and gut homeostasis, so that their dysregulation might contribute to IBD pathogenesis. This review focuses on recent advances of the role of NLRP3 inflammasome signaling in IBD pathogenesis. Improving knowledge of the inflammasome could provide insights into potential therapeutic targets for patients with IBD.

Leukocytapheresis for steroid-dependent ulcerative colitis in clinical practice: results of a nationwide Spanish registry

BACKGROUND

Several small, prospective, open studies suggest that leukocytapheresis might be efficient in patients with steroid-dependent ulcerative colitis (UC).

AIM

To evaluate the short- and long-term effectiveness of leukocytapheresis for the management of steroid-dependent UC in clinical practice.

METHODS

A Web-based, nationwide database specifically designed to record the efficacy and safety data of leukocytapheresis therapy in UC was available from September 2007 in Spain. Clinical data were collected at treatment baseline, 1 month after the last apheresis session (initial efficacy), and 6 and 12 months thereafter (long-term efficacy). Remission was defined as a Mayo Clinic index ≤2 together with complete steroid withdrawal and response as a decrease of ≥3 from the baseline score.

RESULTS

A total of 142 steroid-dependent UC patients were included in the registry, most of them treated with the Adacolumn™ system. In 69% of patients thiopurine therapy failed to achieve steroid-free clinical remission. Initial clinical remission was obtained in 37% of cases. The initial corticosteroid dose, the number and frequency of apheresis sessions, or the previous failure of thiopurines and/or infliximab did not influence the initial remission rate, but a greater decrease in CRP levels was associated with a higher probability to obtain initial remission. At 6 and 12 months, 41 and 36% of patients were in clinical remission, respectively. Only one serious adverse effect was recorded.

CONCLUSIONS

In clinical practice, apheresis allows long-term steroid-free clinical remission in up to one third of steroid-dependent UC patients, even in those with prior failure of thiopurines.

Inhibition of CXCL10 release by monomeric C3bi and C4b

Cellulose acetate (CA) beads are often used for leucocyte apheresis therapy against inflammatory bowel disease. In order to clarify the mechanism of the anti-inflammatory effects of CA, global analysis of the molecules generated in blood by the interaction with CA beads was performed in this study. An activated medium was collected from whole blood that had been preincubated with CA beads, and the effects of the CA-activated medium on leucocyte function were investigated. Fresh blood was stimulated with lipopolysaccharide (LPS) or interferon (IFN)-β in the presence of the activated medium, and levels of chemokines and cytokines, including CXCL10 (IFN-inducible protein-10), and phosphorylated STAT1 (signal transducer and activator of transcription 1), which is known to be essential for CXCL10 production in leucocytes, were measured. IFN-β- or LPS-induced CXCL10 production, expression of CXCL10 mRNA and phosphorylation of STAT1 were significantly reduced in the presence of the medium pretreated with CA beads compared with the control without the CA bead treatment. The factors inhibiting CXCL10 production were identified as the C3 and C4 fragments by mass spectrometry. The monomeric C3bi and C4b proteins were abundant in the medium pretreated with CA beads. Furthermore, purified C3bi and C4b were found to inhibit IFN-β-induced CXCL10 production and STAT1 phosphorylation. Thus, STAT1-mediated CXCL10 production induced by stimulation with LPS or IFN was potently inhibited by monomeric C3bi and C4b generated by the interaction of blood with CA beads. These mechanisms mediated by monomeric C3bi and C4b may be involved in the anti-inflammatory effects of CA.

Acquisition of antigen-presenting functions by neutrophils isolated from mice with chronic colitis

Active episodes of the inflammatory bowel diseases are associated with the infiltration of large numbers of myeloid cells including neutrophils, monocytes, and macrophages. The objective of this study was to systematically characterize and define the different populations of myeloid cells generated in a mouse model of chronic gut inflammation. Using the T cell transfer model of chronic colitis, we found that induction of disease was associated with enhanced production of myelopoietic cytokines (IL-17 and G-CSF), increased production of neutrophils and monocytes, and infiltration of large numbers of myeloid cells into the mesenteric lymph nodes (MLNs) and colon. Detailed characterization of these myeloid cells revealed three major populations including Mac-1(+)Ly6C(high)Gr-1(low/neg) cells (monocytes), Mac-1(+)Ly6C(int)Gr-1(+) cells (neutrophils), and Mac-1(+)Ly6C(low/neg)Gr-1(low/neg) leukocytes (macrophages, dendritic cells, and eosinophils). In addition, we observed enhanced surface expression of MHC class II and CD86 on neutrophils isolated from the inflamed colon when compared with neutrophils obtained from the blood, the MLNs, and the spleen of colitic mice. Furthermore, we found that colonic neutrophils had acquired APC function that enabled these granulocytes to induce proliferation of OVA-specific CD4(+) T cells in an Ag- and MHC class II-dependent manner. Finally, we observed a synergistic increase in proinflammatory cytokine and chemokine production following coculture of T cells with neutrophils in vitro. Taken together, our data suggest that extravasated neutrophils acquire APC function within the inflamed bowel where they may perpetuate chronic gut inflammation by inducing T cell activation and proliferation as well as by enhancing production of proinflammatory mediators.

Processed blood volume impacts clinical efficacy in patients with ulcerative colitis undergoing adsorptive depletion of myeloid lineage leucocytes

BACKGROUND

Hitherto, therapeutic depletion of granulocytes and monocytes by adsorption (GMA) has been associated with significant and insignificant efficacy in patients with ulcerative colitis (UC). Further, the processed blood volume in one GMA session has been fixed at 30 mL/min × 60 min, regardless of patients' body weight (BW). We were interested to see the efficacy and safety of GMA when administered in relation to patients' BW.

METHODS

Sixty patients were randomly assigned to the routine GMA (n = 30) and to GMA adjusted to patients' BW, 60 mL/kg (n = 30). GMA was done with the Adacolumn, up to 10 sessions over 10 weeks. At entry and 1 week post last GMA, patients were clinically and endoscopically evaluated. Remission was defined as clinical activity index (CAI) ≤4, whereas mucosal remission was defined as endoscopic index (EI) ≤3.

RESULTS

In the BW group, the processed volume/session was 3,260 ± 581 versus 1,800 mL in the routine group (P < 0.001). In the BW group, 25 of 30 patients (83.3%) achieved remission versus 19 of 30 patients (63.3%) in the routine group. The average CAI in the BW group fell from 9.6 ± 2.6 to 2.3 ± 2.1 versus from 9.1 ± 2.4 to 4.0 ± 2.1 (P < 0.05) in the routine group. Similarly, the EI in the BW group fell from 9.4 ± 1.3 to 2.1 ± 2.1 versus from 9.2 ± 1.8 to 4.5 ± 2.3 (P < 0.01).

CONCLUSIONS

GMA adjusted to patients' BW and at a vastly greater processed volume produces significantly higher efficacy as compared with the routine GMA protocol. Further, in this study, up to twofold higher processed volume caused no safety concern.

Therapeutic strategies for severe alcoholic hepatitis

BACKGROUND AND AIMS

Severe alcoholic hepatitis (SAH) is an inflammatory response with multiple morbidity factors like leucocytosis, hepatomegaly, renal failure, hepatic encephalopathy, endotoxemia, and has a high mortality rate. Accordingly, identifying therapeutic interventions that can support prognosis is the goal of research.

METHODS

Questionnaires were sent to 1234 medical institutions asking for information on patients with SAH during 2004 to 2008 including patients' demography, disease profile and the therapeutic interventions patients had received during hospitalization.

RESULTS

Twenty-nine hospitals had treated SAH patients, and provided full demographic data on 62 patients. Twenty-seven patients had received no treatment, 10 patients had received granulocytes/monocytes apheresis (GMA) to deplete elevated myeloid linage leucocytes, the rest had received one or more of the following treatments, corticosteroids, plasma exchange (PE) and haemodialysis (HD). Further, 23 patients had died and 39 had survived within 100 days of hospitalization. Serum creatinine (Cr) was higher in patients who had died vs patients who had survived (P=0.026). Likewise, patients with white blood cells (WBC) ≥ 10(4)/μL had higher mortality rate vs patients with WBC<10(4)/μL (P=0.039). GMA in patients with WBC ≥ 10(4)/μL showed 100% prognosis vs patients with WBC ≥ 10(4)/μL who did not receive GMA (P=0.0007). Corticosteroids, PE and HD did not significantly impact prognosis of SAH patients.

CONCLUSIONS

Our perception is that, patients with elevated myeloid leucocytes benefit most from GMA, while PE appears to support patients with coagulation deficiency or high plasma bilirubin and HD has indication in patients with high Cr.

Current and emerging drugs for the treatment of inflammatory bowel disease

During the last decade a large number of biological agents against tumor necrosis factor-α (TNF-α), as well as many biochemical substances and molecules specifically for the medical treatment of patients with inflammatory bowel disease (IBD), have been developed. This enormous progress was a consequence of the significant advances in biotechnology along with the increased knowledge of the underlying pathophysiological mechanisms involved in the pathogenesis of IBD. However, conventional therapies remain the cornerstone of treatment for most patients. During recent years conventional and biologic IBD therapies have been optimized. Newer mesalazine formulations with a reduced pill size and only one dose per day demonstrate similar efficacy to older formulations. New corticosteroids retain the efficacy of older corticosteroids while exhibiting a higher safety profile. The role of antibiotics and probiotics has been further clarified. Significant progress in understanding thiopurine metabolism has improved the effective dose along with adjunctive therapies. Quite a large number of substances and therapies, including biologic agents other than TNF-α inhibitors, unfractionated or low-molecular-weight heparin, omega-3 polyunsaturated fatty acids, microbes and microbial products, leukocytapheresis, and other substances under investigation, could offer important benefits to our patients. In this paper we review the established and emerging therapeutic strategies in patients with Crohn’s disease and ulcerative colitis.