Prospective randomized controlled trial comparing a novel and dedicated device with conventional endoscopic techniques for the treatment of buried bumper syndrome (with video)

BACKGROUND AND AIMS

Buried bumper syndrome (BBS) is a rare adverse event of PEG tubes. This study compared the newly developed Flamingo device (Fujifilm Medwork GmbH, Höchstadt, Germany) with conventional endoscopic techniques for BBS treatment.

METHODS

This prospective, randomized controlled trial compared the Flamingo set (study group) with other endoscopic techniques (control group) for BBS treatment in 6 German hospitals. The primary endpoint was procedure time. Further outcome parameters were technical success, adverse event rate, and number and cost of devices used in each group.

RESULTS

Thirty-six patients (18 in each group; mean age, 73 years; 12 women) were included in this study between March 2018 and December 2022. Median time since placement of the feeding tube was 30 months. The bumper was located in the gastric corpus in 27 patients, and the internal bumper was completely overgrown in 31 patients. The duration of the removal procedure was 17 minutes (range, 3-72) in the study group compared with 38 minutes (range, 12-111) in the control group (P = .046). The primary technical success rate was 77.8% in the study group and 55.6% in the control group (P = .157), whereas the overall technical success rate was 100% compared with 83.3% (P = .070). Adverse events occurred in 4 patients (11.1%).

CONCLUSIONS

Endoscopic removal of the buried bumper using the Flamingo device was significantly faster than that with other endoscopic techniques and showed a higher technical success rate. This device may become the endoscopic treatment of choice for BBS. (Clinical trial registration number: NCT03186066.).

Phase II Study of First-Line Trebananib Plus Sorafenib in Patients with Advanced Hepatocellular Carcinoma

Lessons Learned.

Trebananib leveraging anti‐angiogenic mechanism that is distinct from the classic sorafenib anti‐vascular endothelial growth factor inhibition did not demonstrate improved progression‐free survival at 4 months in patients with advanced hepatocellular carcinoma (HCC).

In support of previously reported high Ang‐2 levels’ association with poor outcome in HCC for patients, trebananib treatment with lower baseline Ang‐2 at study entry was associated with improved overall survival to 22 months and may suggest future studies to be performed within the context of low baseline Ang‐2.

Background.

Ang‐1 and Ang‐2 are angiopoietins thought to promote neovascularization via activation of the Tie‐2 angiopoietin receptor. Trebananib sequesters Ang‐1 and Ang‐2, preventing interaction with the Tie‐2 receptor. Trebananib plus sorafenib combination has acceptable toxicity. Elevated Ang‐2 levels are associated with poor prognosis in hepatocellular carcinoma (HCC).

Methods.

Patients with HCC, Eastern Cooperative Oncology Group ≤2, and Childs‐Pugh A received IV trebananib at 10 mg/kg or 15 mg/kg weekly plus sorafenib 400 mg orally twice daily. The study was planned for ≥78% progression‐free survival (PFS) rate at 4 months relative to 62% for sorafenib historical control (power = 80% α = 0.20). Secondary endpoints included safety, tolerability, overall survival (OS), and multiple biomarkers, including serum Ang‐2.

Results.

Thirty patients were enrolled sequentially in each of the two nonrandomized cohorts. Demographics were comparable between the two arms and the historical controls. PFS rates at 4 months were 57% and 54% on the 10 mg/kg and 15 mg/kg trebananib cohorts, respectively. Median OS was 17 and 11 months, respectively. Grade 3 and above events noted in ≥10% of patients included fatigue, hypertension, diarrhea, liver failure, palmar‐plantar erythrodysesthesia syndrome, dyspnea, and hypophosphatemia. One death was due to hepatic failure. Serum Ang‐2 dichotomized at the median was associated with improved OS in both cohorts.

Conclusion.

There was no improvement in PFS rate at 4 months in either cohort, when compared with sorafenib historical control.

Impact of neo-adjuvant Sorafenib treatment on liver transplantation in HCC patients - a prospective, randomized, double-blind, phase III trial

Background

Liver Transplantation (LT) is treatment of choice for patients with hepatocellular carcinoma (HCC) within MILAN Criteria. Tumour progression and subsequent dropout from waiting list have significant impact on the survival. Transarterial chemoembolization (TACE) controls tumour growth in the treated HCC nodule, however, the risk of tumour development in the untreated liver is increased by simultaneous release of neo-angiogenic factors. Due to its anti-angiogenic effects, Sorafenib delays the progression of HCC. Aim of this study was to determine whether combination of TACE and Sorafenib improves tumour control in HCC patients on waiting list for LT.

Methods

Fifty patients were randomly assigned on a 1:1 ratio in double-blinded fashion at four centers in Germany and treated with TACE plus either Sorafenib (n = 24) or placebo (n = 26). The end of treatment was development of progressive disease according to mRECIST criteria or LT. The primary endpoint of the trial was the Time-to-Progression (TTP). Other efficacy endpoints were Tumour Response, Progression-free Survival (PFS), and Time-to-LT (TTLT).

Results

The median time of treatment was 125 days with Sorafenib and 171 days with the placebo. Fourteen patients (seven from each group) developed tumour progression during the course of the study period. The Hazard Ratio of TTP was 1.106 (95% CI: 0.387, 3.162). The results of the Objective Response Rate, Disease Control Rate, PFS, and TTLT were comparable in both groups. The incidence of AEs was comparable in the placebo group (n = 23, 92%) and in the Sorafenib group (n = 23, 96%). Twelve patients (50%) on Sorafenib and four patients (16%) on placebo experienced severe treatment-related AEs.

Conclusion

The TTP is similar after neo-adjuvant treatment with TACE and Sorafenib before LT compared to TACE and placebo. The Tumour Response, PFS, and TTLT were comparable. The safety profile of the Sorafenib group was similar to that of the placebo group.

Trial registration

ISRCTN24081794

Improvement in gastrointestinal and health-related quality of life outcomes after conversion from mycophenolate mofetil to enteric-coated mycophenolate sodium in liver transplant recipients

OBJECTIVE

To evaluate improvement in gastrointestinal (GI) symptoms and health-related quality of life (HRQoL) in liver transplant recipients switched from mycophenolate mofetil (MMF) to enteric-coated mycophenolate sodium (EC-MPS).

METHODS

A multicenter, open-label, single-arm study was undertaken in maintenance liver transplant recipients who reported GI complications with MMF therapy. The patients were switched to equimolar doses of EC-MPS at baseline. The primary end point was the change in the Gastrointestinal Symptom Rating Scale (GSRS) total score after 6 to 8 weeks of treatment with EC-MPS. Other key assessments for GI symptoms and HRQoL included the GSRS subscores, the Gastrointestinal Quality of Life Index (GIQLI), the Psychological General Well-Being Index, and the Overall Treatment Effect (OTE). Paired t-test was used to assess the difference in the mean score changes over time.

RESULTS

A total of 34 patients were enrolled and switched to equimolar doses of EC-MPS. After 6 to 8 weeks of EC-MPS treatment, mean GSRS total score improved significantly from 2.88 ± 0.66 to 2.10 ± 0.78. Mean improvement in GSRS total score (-0.77 score points; P = .001) exceeded the minimal clinically important difference. Significant improvements were observed in all GSRS subscales (P < .05), GIQLI total scores (P = .001), and GIQLI subscales "GI symptoms" (P < .001) and "physical function" (0.013). Patients who continued EC-MPS reported sustained benefits compared with patients who switched back to MMF after 6 to 8 weeks of treatment with EC-MPS. On the OTE scale, improvement in symptoms was reported in 76.5% and 61.8% of the patients as perceived by the physicians and the patients. Improvement in HRQoL was reported by 41.2% of the patients. No deaths, biopsy proven acute rejections, or graft losses were reported during the study.

CONCLUSION

Conversion from MMF to EC-MPS was associated with a significant improvement in GI symptoms and HRQoL in liver transplant recipients.

The MELD score predicts the short-term and overall survival after liver transplantation in patients with primary sclerosing cholangitis or autoimmune liver diseases

PURPOSE

Liver transplantation (LT) is well established in patients with autoimmune liver disease. Despite excellent outcomes, organ scarcity demands careful patients' selection and timing of transplantation.

METHODS

This retrospective study analyzes data of 79 consecutive patients with primary sclerosing cholangitis (PSC), autoimmune hepatitis (AIH), and overlap syndrome, undergoing LT between 2001 and 2012. Overall survival (OS) and graft survival were assessed using Kaplan-Meier estimate. Multivariate survival analysis was performed to identify prognostic factors by using Cox regression model.

RESULTS

After 59.6-month median follow-up, the 5-year OS and graft survival were 75.3 and 68.8%, respectively. The 5-year survival rates for patients with PSC (n=57), AIH (n=17), and overlap syndrome (n=5) were 76.3, 76.0, and 60.0%. The 90-day mortality rate of 70.0% was significantly higher in patients with a labMELD score≥20 (n=10) compared to 26.1% in 69 patients with a labMELD<20 (p=0.009). A lab Model for End-Stage Liver Disease (MELD) score≥20 was an independent predictor of impaired OS (p=0.050, hazard ratio 2.5). The 5-year OS was 55.7% in patients with a labMELD score≥20 compared to 84.7% in patients with a labMELD score<20.

CONCLUSION

The recipients' MELD score is a predictor for the short-term outcome after LT in patients with autoimmune liver disease. Meticulous selection for transplant listing remains necessary to safe scarce donor organs.

Human and mouse VEGFA-amplified hepatocellular carcinomas are highly sensitive to sorafenib treatment

Death rates from hepatocellular carcinoma (HCC) are steadily increasing, yet therapeutic options for advanced HCC are limited. We identify a subset of mouse and human HCCs harboring VEGFA genomic amplification, displaying distinct biologic characteristics. Unlike common tumor amplifications, this one seems to work via heterotypic paracrine interactions; stromal VEGF receptors (VEGFR), responding to tumor VEGF-A, produce hepatocyte growth factor (HGF) that reciprocally affects tumor cells. VEGF-A inhibition results in HGF downregulation and reduced proliferation, specifically in amplicon-positive mouse HCCs. Sorafenib-the first-line drug in advanced HCC-targets multiple kinases, including VEGFRs, but has only an overall mild beneficial effect. We found that VEGFA amplification specifies mouse and human HCCs that are distinctly sensitive to sorafenib. FISH analysis of a retrospective patient cohort showed markedly improved survival of sorafenib-treated patients with VEGFA-amplified HCCs, suggesting that VEGFA amplification is a potential biomarker for HCC response to VEGF-A-blocking drugs.

SIGNIFICANCE

Using a mouse model of inflammation-driven cancer, we identified a subclass of HCC carrying VEGFA amplification, which is particularly sensitive to VEGF-A inhibition. We found that a similar amplification in human HCC identifies patients who favorably responded to sorafenib-the first-line treatment of advanced HCC-which has an overall moderate therapeutic efficacy.

Compliance and tolerability of subcutaneous hepatitis B immunoglobulin self-administration in liver transplant patients: a prospective, observational, multicenter study

BACKGROUND

Subcutaneous self-administration of hepatitis B immunoglobulin (HBIg) prophylaxis is preferred by patients, but compliance with the assigned regimen in routine practice is undocumented.

MATERIAL AND METHODS

A prospective, observational, 18-week, open-label, single-arm, multicenter study assessed compliance and tolerability in maintenance liver transplant patients self-administering subcutaneous HBIg at home according to local practice.

RESULTS

Sixty-one patients were analyzed (median follow-up 18 weeks, range 14.0-27.9 weeks), with 961/1006 injections (95.5%) administered at home during the study. Other than in 4 patients, HBIg was prescribed for weekly administration (500 IU/L, n=39; 1000 IU/L, n=18) at study entry. Eighteen patients (29.5%) were assigned a dose lower than recommended in the Summary of Product Characteristics. The primary variable of compliance failure, defined as ≥ 1 hepatitis B surface antibody (anti-HBs) serum trough level <100 IU/L, occurred in 4 patients (6.6%; 95% CI 1.8%, 15.9%), 3 of whom were receiving a dose below that recommended for their body weight. Anti-HBs levels exceeded 100 IU/L in all patients at the final visit. Mean (SD) anti-HBs level at the first and final study visits was 248 (97) IU/L and 255 (104) IU/L, respectively. Patient compliance was graded good or very good by physicians in 91.8% of cases. No patients tested positive for HBsAg or HBV-DNA. Four patients experienced ≥ 1 adverse drug reactions, none of which was serious. No patient discontinued HBIg due to adverse events.

CONCLUSIONS

Subcutaneous HBIg home-based self-administration under routine, real-life conditions is well-tolerated and associated with high compliance and maintaining protective anti-HBs serum concentration.

Mycophenolate mofetil combination therapy improves survival after liver transplantation. A single-center retrospective analysis

BACKGROUND

Because the immunosuppressive regimen is a modifiable risk factor after orthotopic liver transplantation (OLT), physicians are nowadays aiming at an optimized and individualized strategy for each patient. The aim of this retrospective study was to examine the impact of different immunosuppressive regimens on the long-term outcome post-OLT based on routine, real-life situations, with particular focus on the subgroups of patients with HCC or HCV.

MATERIAL AND METHODS

Our study included 186 patients who underwent OLT between 1999 and 2008 at the University Hospital Heidelberg, Germany with an available minimum follow-up period of 12 months. Data were collected pre-transplantation, and at 3 months, 6 months, and 12 months post-OLT and every 6 months afterwards.

RESULTS

We found a statistically significant better 5-year survival in the calcineurin inhibitor (CNI) + mycophenolate mofetil (MMF) group vs. CNI - MMF (p=0.01) in the whole study group, in the HCC group (p=0.008), and in the HCV group (p=0.0163). Furthermore, there was a trend towards a prolonged HCV relapse-free 5-year survival rate in the CNI + MMF group of 85.6% vs. 70.8% in the CNI - MMF group, a trend towards a lower incidence of death secondary to infection (30.8% vs. 69.2%), and a trend towards lower rates of acute rejections (22.6% vs. 29%). The type of CNI administered was irrelevant in all respects.

CONCLUSIONS

MMF added to immunosuppressive therapy improves patient survival in OLT recipients in general, as well as in patients with HCC and HCV. Prospective studies are needed to determine if a broader application of MMF post-OLT in combination with CNI-tapering could lead to further outcome improvement.

Hypofractionated carbon ion therapy delivered with scanned ion beams for patients with hepatocellular carcinoma - feasibility and clinical response

Purpose

Photon-based radiation therapy does currently not play a major role as local ablative treatment for hepatocellular carcinoma (HCC). Carbon ions offer distinct physical and biological advantages. Due to their inverted dose profile and the high local dose deposition within the Bragg peak, precise dose application and sparing of normal tissue is possible. Furthermore, carbon ions have an increased relative biological effectiveness (RBE) compared to photons.

Methods and materials

A total of six patients with one or more HCC-lesions were treated with carbon ions delivered by the raster-scanning technique according to our clinical trial protocol. Diagnosis of HCC was confirmed by histology or two different imaging modalities (CT and MRI) according to the AASLD-guidelines. Applied fractionation scheme was 4 × 10 Gy(RBE). Correct dose application was controlled by in-vivo PET measurement of β + −activity in the irradiated tissue shortly after treatment.

Results

Patients were observed for a median time period of 11.0 months (range, 3.4 – 12.7 months). Imaging studies showed a partial response in 4/7 lesions and a stable disease in 3/7 lesions in follow-up CT- and MRI scans. Local control was 100%. One patient with multifocal intrahepatic disease underwent liver transplantation 3 months after carbon ion therapy. During radiotherapy and the follow-up period no severe adverse events have occurred.

Conclusions

We report the first clinical results of patients with HCC undergoing carbon ion therapy using the rasterscanning technique at our institution. All patients are locally controlled and experienced no higher toxicities in a short follow-up period. Further patients will be included in our prospective Phase-I clinical trial PROMETHEUS-01 (NCT01167374).

Technical and clinical outcome of transjugular intrahepatic portosystemic stent shunt: bare metal stents (BMS) versus viatorr stent-grafts (VSG)

PURPOSE

To compare retrospectively angiographical and clinical results in patients undergoing transjugular intrahepatic portosystemic stent-shunt (TIPS) using BMS or VSG.

MATERIALS AND METHODS

From February 2001 to January 2010, 245 patients underwent TIPS. From those, 174 patients matched the inclusion criteria with elective procedures and institutional follow-up. Group (I) consisted of 116 patients (mean age, 57.0±11.1 years) with BMS. Group (II) consisted of 58 patients with VSG (mean age, 53.5±16.1 years). Angiographic and clinical controls were scheduled at 3, 6 and 12 months, followed by clinical controls every 6 months. Primary study goals included hemodynamic success, shunt patency as well as time to and number of revisions. Secondary study goals included clinical success.

RESULTS

Hemodynamic success was 92.2% in I and 91.4% in II (n.s.). Primary patency was significantly higher in II compared to I (53.8% after 440.4±474.5 days versus 45.8% after 340.1±413.8 days; p<0.05). The first TIPS revision was performed significantly later in II compared to I (288.3±334.7 days versus 180.1±307.0 days; p<0.05). In the first angiographic control, a portosystemic pressure gradient ≥15 mmHg was present in 73.9% in I and in 39.4% in II (p<0.05). Clinical success was 73.7-86.2% after 466.3±670.1 days in I and 85.7-90.5% after 617.5±642.7 days in II (n.s.). Hepatic encephalopathy was 37.5% in I and 36.5% in II (n.s.).

CONCLUSION

VSG increased primary shunt patency as well as decreased time to and number of TIPS revisions. There was a trend of higher clinical success in VSG without increased hepatic encephalopathy.

Immunomonitoring of nuclear factor of activated T cells-regulated gene expression: the first clinical trial in liver allograft recipients

Long-term calcineurin inhibitor (CNI) treatment can cause serious side effects in liver allograft recipients. An optimal risk-to-benefit ratio for CNI blood levels has not been established. Pharmacodynamic drug monitoring through the measurement of the CNI biological activity, that is, the expression of nuclear factor of activated T cells (NFAT)-regulated genes, seems to be a promising approach. The residual gene expression (RGE) of NFAT-regulated genes 2 and 1.5 hours after cyclosporine A (CsA) and tacrolimus (FK-506) intake was measured in 100 liver allograft recipients with 1 or more years of follow-up post-transplantation. The mean RGE in all patients was 62% ± 33%. A significant negative correlation between the CsA (P < 0.0001, r = -0.8026) and FK-506 peak levels (P < 0.0001, r = -0.6982) and the RGE of all NFAT-regulated genes was observed. Clinical reliability was proven too. In conclusion, the data presented in this pilot study reveal the applicability of the pharmacodynamic monitoring of CNI efficacy in liver allograft recipients. To confirm the advantage of individualized pharmacodynamic drug monitoring over pharmacokinetic drug monitoring with respect to clinical outcomes, controlled, prospective studies are needed.

Phase i study evaluating the treatment of patients with hepatocellular carcinoma (HCC) with carbon ion radiotherapy: the PROMETHEUS-01 trial

Background

Treatment options for patients with advanced hepatocellular carcinoma (HCC) are often limited. In most cases, they are not amenable to local therapies including surgery or radiofrequency ablation. The multi-kinase inhibitor sorafenib has shown to increase overall survival in this patient group for about 3 months.

Radiation therapy is a treatment alternative, however, high local doses are required for long-term local control. However, due to the relatively low radiation tolerance of liver normal tissue, even using stereotactic techniques, delivery of sufficient doses for successful local tumor control has not be achieved to date.

Carbon ions offer physical and biological characteristics. Due to their inverted dose profile and the high local dose deposition within the Bragg peak precise dose application and sparing of normal tissue is possible. Moreover, in comparison to photons, carbon ions offer an increased relative biological effectiveness (RBE), which can be calculated between 2 and 3 depending on the HCC cell line as well as the endpoint analyzed.

Japanese Data on the evaluation of carbon ion radiation therapy showed promising results for patients with HCC.

Methods/Design

In the current Phase I-PROMETHEUS-01-Study, carbon ion radiotherapy will be evaluated for patients with advanced HCC. The study will be performed as a dose-escalation study evaluating the optimal carbon ion dose with respect to toxicity and tumor control.

Primary endpoint is toxicity, secondary endpoint is progression-free survival and response.

Discussion

The Prometheus-01 trial ist the first trial evaluating carbon ion radiotherapy delivered by intensity-modulated rasterscanning for the treatment of HCC. Within this Phase I dose escalation study, the optimal dose of carbon ion radiotherapy will be determined.

Trial registration

NCT 01167374

Clinical update on the SHELTER study: A phase I/II trial of the HDAC inhibitor resminostat in patients with sorafenib-resistant hepatocellular carcinoma (HCC)

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Background: Resminostat (4SC-201) is a novel oral pan-HDAC inhibitor in clinical development in a variety of cancer indications. The aim of the SHELTER study is to evaluate safety, tolerability, and efficacy in patients (pts) with HCC exhibiting progressive disease under sorafenib first-line therapy.

Methods: Sorafenib-refractory pts with advanced HCC, BCLC B or C are included in a multicenter, open-label, two-arm parallel group trial. Resminostat is administered orally on three dose levels of 200 (DL1), 400 (DL2), and 600 mg (DL3) once daily, in combination with 400 mg sorafenib (arm A) or as mono therapy (600 mg, arm B). For arm A, a precedent dose escalation of resminostat and sorafenib is performed to determine the MTD. Resminostat is administered in a “5+9” dosing schedule, consisting of 5 consecutive treatment days (D1-5) followed by a 9-day rest period resulting in 14 day cycles. In arm A sorafenib is given twice daily throughout the treatment period. Primary objective is to determine progression-free survival rate after 12 weeks (6 cycles). Secondary objectives include safety and tolerability, tumor response, estimation of TTP, OS, assessment of PK, and biomarkers.

Results: To date, 14 pts were treated either with 600 mg resminostat alone or on DL1-3 in combination with 400 mg sorafenib. The majority of AE observed so far include gastrointestinal disorders such as nausea and vomiting. Plasma exposure to resminostat increased dose-dependently on D1 (cycle 1) with mean AUC 0-6 h values of 10.5 h*mg/L (600 mg mono) and 9.01 h*mg/L (DL3). No major changes in PK characteristics of resminostat were found with or without co-administration of sorafenib. A considerable portion of patients showed stabilization of their disease (SD): 9 out of 12 pts and 4 out of 5 pts examined after 6 and 12 weeks, respectively, displayed SD. In one patient treated on DL2, SD persisted for 36 weeks along with good long-term tolerability.

Conclusions: Preliminary clinical data confirmed the favorable oral drug profile of resminostat either in mono or in combination treatment with sorafenib. Initial data on therapeutic activity to overcome resistance to sorafenib are promising.

[Table: see text]

Regulation of enterocyte apoptosis by acyl-CoA synthetase 5 splicing

BACKGROUND AND AIMS

The constant renewal of enterocytes along the crypt-villus axis (CVA) of human small intestine is due to cell-inherent changes resulting in the apoptotic cell death of senescent enterocytes. The aim of the present study was to examine underlying molecular mechanisms of the cell death at the villus tip.

METHODS

Characterization of human acyl-coenzyme A (CoA) synthetase 5 (ACSL5) was performed by cloning, recombinant protein expression, biochemical approaches, and several functional and in situ analyses.

RESULTS

Our data show that different amounts of acyl-CoA synthetase 5-full length (ACSL5-fl) and a so far unknown splice variant lacking exon 20 (ACSL5-Delta 20) are found in human enterocytes. In contrast with the splice variant ACSL5-Delta 20, recombinant and purified ACSL5-fl protein is active at a highly alkaline pH. Over expression of ACSL5-fl protein is associated with a decrease of the anti-apoptotic FLIP protein in a ceramide-dependent manner and an increased cell-surface expression of the death receptor TRAIL-R1. Expression analyses revealed that the ACSL5-fl/ACSL5-Delta 20 ratio increases along the CVA, thereby sensitizing ACSL5-fl-dominated cells at the villus tip to the death ligand TRAIL, which is corroborated by functional studies with human small intestinal mucosal samples and an immortalized human small intestinal cell line.

CONCLUSIONS

Our results suggest an ACSL5-dependent regulatory mechanism that contributes to the cellular renewal along the CVA in human small intestine. Deregulation of the ACSL5-fl/ACSL5-Delta 20 homeostasis in the maturation and shedding of cells along the CVA might also be of relevance for the development of intestinal neoplasia.

Emergence of oligoclonal T cell populations following therapeutic T cell depletion in rheumatoid arthritis

OBJECTIVE

To examine the compartment of CD4+ T cells in patients with rheumatoid arthritis (RA) who have developed persistent lymphopenia following antibody-mediated T cell depletion and to investigate why T cell depletion is of limited therapeutic efficacy.

METHODS

Circulating T lymphocytes from 10 patients with seropositive RA treated with the monoclonal antibody (MAb) CAMPATH-1H were longitudinally monitored by fluorescence-activated cell sorter analysis with MAb. To assess the molecular diversity of repopulating T cells, random samples of T cell clones from the peripheral blood of 3 patients were analyzed by sequencing the T cell receptor (TCR) beta chains. At the time of recurring disease, the synovial tissue was examined by immunohistochemistry, and the repertoires of peripheral and synovial tissue T cells were compared by TCR beta-chain sequencing and by semiquantitative hybridization with oligonucleotides specific for the V-D-J beta junctional region of selected clones.

RESULTS

The reconstitution of the peripheral T cell compartment was very slow. A mean CD4+ T cell count of 105/microliters was reached 34 weeks following MAb treatment. After treatment, the percentage of CD4+ T cells with the CD45RO+ phenotype was significantly increased (P = 0.001), indicating the expansion of antigen-primed memory T cells. TCR beta-chain sequences revealed a marked restriction in the diversity of repopulating T cells with the emergence of dominant clonotypes. Despite the low counts of peripheral CD4+ T cells, the synovial tissue was infiltrated by CD4+ T cells to a similar extent as that in RA patients not treated with MAb. Selected clonotypes that had emerged in the peripheral blood compartment dominated the repertoire of tissue-infiltrating T cells in the synovium.

CONCLUSION

In patients with RA, T cell depletion induces a long-term imbalance in T cell homeostasis. Clonal proliferation of CD4+ T cells severely restricts the diversity of available T cell specificities and results in the emergence of dominant clonotypes, which accumulate in the synovial tissue despite peripheral lymphopenia.