Mechanisms underlying the effects of leukocyte apheresis with a fiber filter in a rat model of dextran sulfate sodium-induced colitis

Safety and efficacy of single-needle leukocyte apheresis for treatment of ulcerative colitis

Leukocyte apheresis (LCAP) is a safe and effective treatment for active ulcerative colitis (UC) in Japan. Nevertheless, a limitation of LCAP is its requirement for two puncture sites (double-needle [DN] apheresis), sometimes leading to problems with needle puncture. Single-needle (SN) apheresis is useful in hemodialysis and reduces needle puncture pain. If SN apheresis were found to be useful in LCAP for UC, it may reduce patient burden. The aim of this study was to compare the safety and efficacy of SN apheresis with that of DN apheresis. Twenty-four patients with active UC were retrospectively enrolled. They underwent either SN apheresis (n = 12) or conventional double-needle (DN) apheresis (n = 12) at the Kurume University Hospital from February 2014 to March 2018. At each session, we recorded access problems defined by the time required to initiate apheresis and the frequency of puncture-related problems, as well as blood circuit clotting, defined as clotting necessitating interruption of apheresis and changing of the circuit. Efficacy was assessed using partial Mayo scores. The number of apheresis sessions was comparable between SN and DN apheresis (9.0 ± 2.0 times vs 9.6 ± 1.4 times, mean ± SEM). SN significantly reduced the time required to start apheresis (10.0 ± 5.4 minutes vs 19.4 ± 11.9 minutes, P < .05) as well as needle puncture troubles (0.9% vs 11.5%, P < .05). SN had comparable frequency of blood clotting episodes (5.6% vs 8.7%). SN apheresis had similar clinical efficacy (P < .001 in SN and P < .01 in DN). The improvement and remission rates were comparable between groups. SN apheresis may be safe and effective and may reduce patient burden during UC treatment. Nevertheless, further comparative studies are needed.

Leukocyte Apheresis Using a Fiber Filter Suppresses Colonic Injury Through Calcitonin Gene-Related Peptide Induction

BACKGROUND

The aim of this study was to address whether the therapeutic effect of leukocytapheresis (LCAP) depends on calcitonin gene- related peptide (CGRP) induction.

METHODS

An HLA-B27 transgenic rat model was treated with an LCAP column. The effects of LCAP on clinical, endoscopic, and histologic disease activity, the colony-forming ability of colony-forming unit (CFU)-granulocyte macrophages (GMs), colonic blood flow, and tissue expression of tumor necrosis factor (TNF)-α and CGRP were examined. Changes in the effects of LCAP after pretreatment with the CGRP antagonist CGRP8-37 were also observed. A dextran sulfate sodium-induced colitis rat model included treatment with CGRP, and the effect was assessed based on clinical, endoscopic, and histologic disease activity, colonic blood flow, the colony-forming ability of CFU-GMs, and tissue expression of inflammatory cytokines and CGRP receptor families.

RESULTS

LCAP improved disease activity, enhanced colonic blood flow, and induced the bone marrow colony-forming ability of CFU-GMs with an increase in CGRP mRNA levels. These effects were abolished by pretreatment with CGRP8-37. The administration of CGRP suppressed colitis, promoting colonic blood flow, inducing bone marrow-derived cells, downregulating inflammatory cytokines, and upregulating receptor activity-modifying protein-1. The mRNA and protein levels of inflammatory cytokines in lipopolysaccharide-stimulated mononuclear cells were also decreased after CGRP treatment.

CONCLUSIONS

The therapeutic effects of LCAP depend on CGRP induction. CGRP can effectively suppress colitis through the downregulation of inflammatory events and upregulation of protective events.

Univariate analysis to examine predictors of response to leukocytapheresis in ulcerative colitis patients

Leukocytapheresis (LCAP) is reportedly effective for the treatment of active ulcerative colitis (UC) and is a therapeutic option for steroid-dependent or steroid-resistant patients with UC. However, a consensus regarding the use of LCAP for UC patients has not yet been established. Therefore, we analyzed patients' records to identify predictors of response to LCAP therapy and subsequent recurrence. Between October 2001 and March 2011, we recruited 41 patients who had been diagnosed as having UC and had received LCAP therapy. Patients diagnosed with moderate to severe UC with left-side or total colitis and received LCAP therapy for the first time were enrolled. We retrospectively performed a univariate analysis using the patients' medical records to identify factors affecting the therapeutic effect of LCAP. Body mass index exceeding 18.5 kg/m(2) was found to influence the therapeutic effect of LCAP. Male sex was correlated with a rapid response to LCAP treatment and the maintenance of remission. UC patients experiencing their first attack or had an elevated C-reactive protein level prior to LCAP therapy exhibited a relatively long remission period. In the "after LCAP therapy" group, a low Rachmilewitz endoscopic score, low erythrocyte sedimentation rate, or high white blood cell count was associated with a long remission period. Our results suggest that LCAP should be performed for the treatment of early-onset UC. LCAP can be expected to induce a long remission period, enabling mucosal healing, although the factors that affected the remission period did not influence the therapeutic effect and responsiveness.