Residual Recurrence of a Small Intestinal Capillary Hemangioma with Obscure Gastrointestinal Bleeding Treated by Double-Balloon Endoscopy: A Case Report and Literature Review.

An 86-year-old man presented with anemia. He underwent abdominal contrast-enhanced computed tomography, gastroscopy, and colonoscopy without any bleeding detected. Small bowel capsule endoscopy (SBCE) revealed a reddish polypoid lesion with blood oozing into the jejunum. Antegrade double-balloon endoscopy (DBE) revealed a 5 mm sized protrusion into the jejunum. Endoscopic mucosal resection (EMR) was difficult; the lesion was snared and resected before energization. Clips prevented further bleeding and the lesion's position was marked with a tattoo. Histopathological examination of the lesion led to a diagnosis of capillary hemangioma. After 11 months, the patient was again anemic. A reddish polypoid lesion oozing blood near the tattoo was found by SBCE. Another antegrade DBE showed a 7 mm sized protrusion near the tattoo. The lesion was successfully treated by EMR. Histopathological examination revealed the residual recurrence of a small intestinal capillary hemangioma. The patient recovered from anemia after the EMR. Two months later, SBCE showed no findings around the tattoo. Hemangiomas account for 7-10% of benign small intestinal tumors; most are cavernous hemangiomas, and capillary hemangiomas are rare. We report a rare case of a recurring small intestinal capillary hemangioma detected by SBCE and treated using DBE. We also review the literature.

Remission Factors for Ustekinumab Treatment of Ulcerative Colitis: A Multicenter Retrospective Study of Real-World Data in Japan.

Ustekinumab (UST) is an anti-IL-12/23p40 monoclonal antibody used to treat inflammatory bowel disease. The aim of this retrospective, multicenter study was to investigate the effectiveness of UST administration in achieving remission in patients with ulcerative colitis (UC) and to determine patient characteristics that influence its effectiveness. Of 88 UC patients who received UST from March 2020 to August 2023, 47 with traceable data and for whom 56 weeks had elapsed since the start of treatment received UST to induce remission. The remission rates at 8 weeks were 66% overall, 73.7% for Bio Naïve (never used biologics/JAK inhibitors), and 60.7% for Bio Failure (used biologics/JAK inhibitors) groups. Remission rates at 56 weeks were 70.2% overall, 73.7% for Bio Naïve, and 67.9% for Bio Failure groups. Ustekinumab showed good mid-to-long-term results in the induction of remission of UC in both Bio Naïve and Bio Failure groups. The group showing remission at 8 weeks had a significantly higher non-relapse or continuation rate (proportion of patients with no worsened symptoms necessitating surgery/drug change) at 56 weeks. Predictive factors for achieving remission after UST in UC were female gender, low body mass index, and low lymphocyte-to-monocyte ratio. Thus, UST is effective for moderate-to-severe UC.

Small Intestinal Arteriovenous Malformation Treated by Double-balloon Endoscopy: A Case Report.

A 42-year-old man was referred to our hospital because of anemia. The patient underwent gastroscopy and colonoscopy, but no bleeding site was detected. Abdominal contrast-enhanced computed tomography (CT) showed vascular dilatation along the wall of the small intestine. Small bowel capsule endoscopy and antegrade double-balloon endoscopy (DBE) were performed, and the patient was diagnosed with a small intestinal arteriovenous malformation (AVM). The AVM was clipped using DBE. After clipping, abdominal contrast-enhanced CT and small bowel angiography revealed the disappearance of the AVM. DBE may be a viable therapeutic option, helping avoid surgery and its associated risks.

Enterolith Treated with a Combination of Double-Balloon Endoscopy and Cola Dissolution Therapy.

A 71-year-old woman with rheumatoid arthritis who had been taking NSAIDs for many years consulted our hospital for abdominal pain. She was diagnosed with a small bowel obstruction due to an enterolith according to an abdominal CT scan that showed dilation from the enterolith in the small intestine on the oral side. It was considered that the intestinal stone was formed due to stagnation of intestinal contents and had gradually increased in size, resulting in an intestinal obstruction. We performed antegrade double-balloon endoscopy (DBE) to observe and remove the enterolith. We used forceps and a snare to fracture the enterolith. During this attempt, we found a seed in the center of the enterolith. Since the intestinal stone was very hard, cola dissolution therapy was administered from an ileus tube for 1 week. The following week, DBE was performed again, and it was found that the stone had further softened, making attempts at fracture easier. Finally, the enterolith was almost completely fractured. Intestinal stenosis, probably due to ulcers caused by NSAIDs, was found. Small bowel obstruction with an enterolith is rare. In this case, it was considered that the seed could not pass through the stenotic region of the small intestine and the intestinal contents had gradually built up around it. It has been suggested that DBE may be a therapeutic option in cases of an enterolith. Further, cola dissolution therapy has been shown to be useful in treating an enterolith, with the possible explanation that cola undergoes an acid-base reaction with the enterolith. In summary, we report, for the first time, treatment of an enterolith with a combination of DBE and cola dissolution therapy, thereby avoiding surgery and its risks.

Differential diagnosis of ulcerative colitis with increased diarrhea; collagenous colitis or irritable bowel syndrome? A case report.

A 50-year-old man with a 20-year history of left-sided ulcerative colitis (UC) presented to our hospital with sudden onset of watery diarrhea. To this point, he had been treated with mesalazine 2.0 g/day for UC and had maintained remission. We considered that the UC had worsened. We immediately performed surveillance colonoscopy, which revealed a normal mucous membrane. The results of blood laboratory examinations were normal. Histopathology of colonic biopsies revealed new-onset collagenous colitis (CC), with a thickened subepithelial collagen band (SECB) and inactive UC. We herein report the importance of random colonic biopsies to diagnose CC even when the endoscopic appearance of the colon is normal in patients with inflammatory bowel disease with worsened diarrhea.

Efficacy of cytapheresis for induction therapy and extra-intestinal skin manifestations of ulcerative colitis.

INTRODUCTION: In recent years, the prevalence of inflammatory bowel diseases has been increasing in Japan due to the westernization of lifestyles. Many patients have been reported to have extra-intestinal manifestations (EIMs) at least once. Skin lesions occur with a high degree of frequency among EIMs, with erythema nodosum (EN) and pyoderma gangrenosum (PG) the main complications. Cytapheresis is again attracting attention as a treatment with few side effects. METHODS: We investigated the therapeutic effect of cytapheresis on ulcerative colitis (UC) and cutaneous EIMs. Between 2008 and 2021, 240 patients with active UC had induction therapy by cytapheresis at our hospital. RESULTS: Remission and response rates were 50.0% and 67.5%, respectively. Apheresis was performed on seven patients with PG and five patients with EN with a good response. Serious adverse events were not observed. CONCLUSION: This retrospective assessment of efficacy showed that EN and PG responded favorably to cytapheresis.

A Comparative Study of Early Mucosal Healing Following Hot Polypectomy and Cold Polypectomy.

BACKGROUND Cold polypectomy (CP) and hot polypectomy (HP) are both accepted methods for polypectomy. In recent years, the use of CP has increased for reasons of safety. However, there have been few investigations of conditions at follow-up early after resection. This prospective study from a single center aimed to compare colonic mucosal healing at 1 week following HP vs CP of benign colonic polyps <10 mm in diameter. MATERIAL AND METHODS Six patients with a total of 52 lesions under 10 mm in size were randomized to either the HP group (n=25) or CP group (n=27) using information in opaque envelopes. One week after endoscopic treatment, the site of treatment was evaluated using colonoscopy. We assessed the mean tumor size, ulcer diameter, exposed blood vessels, residual lesion, and complications. RESULTS Mean tumor size did not differ between the 2 groups (CP vs HP: 5.41 mm vs 5.68 mm). The CP group had a smaller ulcer base diameter (2.70 mm vs 4.84 mm; P<0.05) and fewer exposed blood vessels than the HP group (3.7% vs 36.0%; P<0.05). One residual lesion was found in the CP group. No patients experienced delayed perforation or post-polypectomy bleeding. CONCLUSIONS Our study findings showed that at 1-week follow-up, cold polypectomy resulted in improved colonic mucosal healing, with a smaller ulcer diameter and fewer blood vessels, when compared with hot polypectomy.

Bacteroidetes Species Are Correlated with Disease Activity in Ulcerative Colitis.

Fecal microbiota transplantation following triple-antibiotic therapy (amoxicillin/fosfomycin/metronidazole) improves dysbiosis caused by reduced Bacteroidetes diversity in patients with ulcerative colitis (UC). We investigated the correlation between Bacteroidetes species abundance and UC activity. Fecal samples from 34 healthy controls and 52 patients with active UC (Lichtiger's clinical activity index ≥5 or Mayo endoscopic subscore ≥1) were subjected to next-generation sequencing with HSP60 as a target in bacterial metagenome analysis. A multiplex gene expression assay using colonoscopy-harvested mucosal tissues determined the involvement of Bacteroidetes species in the mucosal immune response. In patients with UC, six Bacteroides species exhibited significantly lower relative abundance, and twelve Bacteroidetes species were found significantly correlated with at least one metric of disease activity. The abundance of five Bacteroidetes species (Alistipes putredinis, Bacteroides stercoris, Bacteroides uniformis, Bacteroides rodentium, and Parabacteroides merdae) was correlated with three metrics, and their cumulative relative abundance was strongly correlated with the sum of Mayo endoscopic subscore (R = -0.71, p = 2 × 10-9). Five genes (TARP, C10ORF54, ITGAE, TNFSF9, and LCN2) associated with UC pathogenesis were expressed by the 12 key species. The loss of key species may exacerbate UC activity, serving as potential biomarkers.

Single-cell atlas of colonic CD8+ T cells in ulcerative colitis.

Colonic antigen-experienced lymphocytes such as tissue-resident memory CD8+ T cells can respond rapidly to repeated antigen exposure. However, their cellular phenotypes and the mechanisms by which they drive immune regulation and inflammation remain unclear. Here we compiled an unbiased atlas of human colonic CD8+ T cells in health and ulcerative colitis (UC) using single-cell transcriptomics with T-cell receptor repertoire analysis and mass cytometry. We reveal extensive heterogeneity in CD8+ T-cell composition, including expanded effector and post-effector terminally differentiated CD8+ T cells. While UC-associated CD8+ effector T cells can trigger tissue destruction and produce tumor necrosis factor (TNF)-α, post-effector cells acquire innate signatures to adopt regulatory functions that may mitigate excessive inflammation. Thus, we identify colonic CD8+ T-cell phenotypes in health and UC, define their clonal relationships and characterize terminally differentiated dysfunctional UC CD8+ T cells expressing IL-26, which attenuate acute colitis in a humanized IL-26 transgenic mouse model.

Effectiveness of Cytapheresis for Ulcerative Colitis in Special Situations: Delayed Onset of Optimum Efficacy in Elderly Patients.

BACKGROUND: Cytapheresis is a non-pharmacologic treatment option in which depleting elevated/activated leucocytes is known to exacerbate and perpetuate ulcerative colitis (UC) by releasing inflammatory cytokines. Therefore, it is a relevant treatment for elderly patients who wish to avoid pharmacologicals. METHODS: The efficacy of Cytapheresis for remission induction in 72 patients who received Cytapheresis for active UC at our hospital was retrospectively evaluated. Patients included 11 elderly cases, patients on steroids, biologics, calcineurin inhibitor, and 13 with extra-intestinal complications. Lichtiger's UC clinical activity index ≤4 meant remission was assessed at the end of therapy and then 1 month later. The efficacy on extra-intestinal manifestations meant improvement of the main morbidity. RESULTS: At the end of Cytapheresis therapy, the remission rate in the elderly was 36.4%, and 54.2% in the non-elderly patients. One-month post Cytapheresis, the remission rate in the elderly had increased to 72.7% (p = 0.042), but to 58.3% in the non-elderly, suggesting a delayed response phenomenon in the elderly. The efficacy of Cytapheresis in 4 cases with loss of response to biologics was 75%, and 84.6% in the 13 patients with extra-intestinal complications, indicating a dramatic efficacy on dermatitis and arthralgia. CONCLUSIONS: Unlike pharmacologicals, the efficacy of Cytapheresis appears to be time dependent. Accordingly, in the elderly, we observed a delayed response, indicating that elderly patients may respond beyond the end of Cytapheresis therapy. Therefore, patients who do not show efficacy at the end of Cytapheresis therapy should be followed up for delayed response. Further, Cytapheresis is favored by patients for its good safety profile.

Efficacy and Acceptability of 1 Liter of Polyethylene Glycol with Ascorbic Acid vs. 2 Liters of Polyethylene Glycol Plus Mosapride and Sennoside for Colonoscopy Preparation.

BACKGROUND [color=black]Bowel preparation is an important factor for an optimal outcome of colonoscopy. Recently, polyethylene glycol (PEG) solution has been in common use for bowel cleansing for colonoscopy, but some patients are intolerant of PEG because of taste or volume. A low-volume PEG administered with ascorbic acid solution (PEG-Asc) was designed to improve tolerability, but the administration of this method is more complex than that with PEG alone. This study aimed to compare bowel cleansing efficacy, safety, and tolerability of 1 L PEG-Asc with a 2 L PEG preparation with use of sennosides and mosapride.[/color] MATERIAL AND METHODS [color=black]This was a prospective, single-center, non-inferiority trial that included 112 patients (PEG-Asc group, 68; PEG group, 44). The primary endpoint was the efficacy of colon cleansing assessed by endoscopists using a validated 4-point scale according to the Aronchick scale and was verified by a blinded investigator. Acceptability, tolerability, and adenoma detection rate (ADR) of these 2 regimens were secondary endpoints.[/color][color=black] [/color] RESULTS [color=black]We found no statistically significant differences between the groups in colon-cleansing efficacy or in the adenoma detection rate (ADR). Moreover, overall, patients significantly favored PEG-Asc over PEG, reflecting better acceptance of PEG-Asc. Additionally, more patients favored PEG-Asc over PEG for a hypothetical future colonoscopy. [/color] CONCLUSIONS [color=black]The alternate 1 L PEG-Asc regimen and standard 2 L PEG regimen were clinically equivalent with respect to cleansing efficacy, safety, and ADR, and more patients favored PEG-Asc than PEG. This alternate regimen may improve patient compliance and acceptance of surveillance colonoscopy.[/color].

Efficacy of cytapheresis for remission induction and dermatological manifestations of ulcerative colitis.

BACKGROUND: In ulcerative colitis (UC) patients, cytapheresis depletes elevated and activated leucocytes, which are known to release inflammatory cytokines including tumor necrosis factor (TNF)-α. Further, there are UC patients who develop erythema nodosum (EN) or pyoderma gangrenosum (PG) as extra-intestinal manifestations of UC. METHODS: Between 2008 and 2015, 181 consecutive patients with active UC received cytapheresis with either a granulocyte and monocyte apheresis (GMA) column or with a leucocyte removal filter (LCAP) as remission induction therapy. Each patient received weekly or intensive (2-3 sessions/week) cytapheresis up to 10 sessions. In 13 patients, UC was complicated by EN or PG. Lichtiger's clinical activity index (CAI) ≤4 meant remission, while ≥3 decrease in CAI meant response to therapy. Prednisolone sparing and the changes in the extra-intestinal manifestations were factored for assessing treatment efficacy. RESULTS: The overall remission and response rates were 52.5% and 71.8%, respectively, CAI fell from 9.4 ± 3.3 to 4.9 ± 3.5 (P < 0.001). The efficacy rates in subgroups on concomitant corticosteroid, anti-TNF or tacrolimus, and those without concomitant medications were not significantly different (P > 0.05). However, in 84 patients on prednisolone, the average daily prednisolone dose was reduced from 18.15 to 12.43 mg/day (P < 0.001) with 21.7% being corticosteroid free. All patients with EN or PG showed favorable response to cytapheresis, notably 2 EN patients achieving remission after just 2 cytapheresis sessions without concomitant medication. CONCLUSIONS: In this retrospective efficacy evaluation, cytapheresis was effective as remission induction therapy with steroid sparing effect and desirable safety profile. Further, patients with EN or PG responded favorably to cytapheresis.

Continuation of antithrombotic therapy may be associated with a high incidence of colonic post-polypectomy bleeding.

BACKGROUND AND AIM: Post-polypectomy bleeding (PPB) is the most common complication of endoscopic procedures. To reduce the risk of thromboembolic incidents, Japanese guidelines for gastroenterological endoscopy were revised to indicate that antithrombotic agents were not to be discontinued for endoscopic treatment. However, carrying out endoscopic procedures under antithrombotic medication potentially increases the incidence of hemorrhagic complications. The present study investigated the impact of the revised guidelines on the frequency of complications after colonoscopic procedures. METHODS: The surveillance period comprised the year before the initiation of the new guidelines (2012), which served as a control period, and 2 years after initiation of the new guidelines (2013 and 2014). During the control period, 3955 cases were examined colonoscopically and 1601 lesions were treated endoscopically. During the 2-year period under the new guidelines, 8749 colonoscopies and 3768 endoscopic treatments were carried out. Changes in treatment methods and rates of complications were compared. RESULTS: PPB rate was not significantly different before and after the revision (0.87% vs 1.01%). With the new guidelines, PPB rates in antithrombotic non-users and users were 0.60% and 3.13%, respectively (OR 5.11, P = 0.000). Multivariable analysis showed that the risks for PPB were as follows: heparin bridging therapy (OR 6.34, P = 0.0002); low-dose aspirin (LDA) continuation (OR 5.30, P = 0.0079); and lesion size (OR 1.06, P < 0.0001). CONCLUSION: The present study showed that the overall PPB rate under the new guidelines was not significantly higher when compared with the previous data obtained before the new guidelines were introduced.

Changes in Intestinal Microbiota Following Combination Therapy with Fecal Microbial Transplantation and Antibiotics for Ulcerative Colitis.

BACKGROUND: Fecal microbiota transplantation (FMT) is a potential therapeutic approach to restore normal intestinal microbiota in patients with ulcerative colitis (UC), which is associated with dysbiosis; however, treatment efficacy remains unclear. Hence, we studied the impact of antibiotic pretreatment with amoxicillin, fosfomycin, and metronidazole (AFM therapy) and FMT versus AFM alone. METHODS: AFM therapy was administered to patients for 2 weeks until 2 days before FMT. Patients' spouses or relatives were selected as donor candidates. Donor fecal samples were collected on the day of administration and transferred into the patient's colon by colonoscopy within 6 hours. Microbiome analysis was performed by 16S rRNA next-generation sequencing. RESULTS: Patients with mild-to-severe active UC (combination-therapy group, n = 21; AFM monotherapy group, n = 20) were included. Thirty-six patients completed this assessment (combination-therapy group, n = 17; AFM monotherapy group, n = 19). A higher clinical response was observed after combination therapy compared with AFM monotherapy at 4 weeks after treatment. After the 2-week AFM therapy, the Bacteroidetes composition was nearly abolished. The Bacteroidetes proportion recovered in clinical responders at 4 weeks after FMT was not observed in the AFM monotherapy group. Persistent antimicrobial-associated dysbiosis found in the AFM monotherapy group was reversed by FMT. The recovery rate of Bacteroidetes at 4 weeks after FMT correlated with endoscopic severity. CONCLUSIONS: FMT following antimicrobial bowel cleansing synergistically contributes to the recovery of the Bacteroidetes composition, which is associated with clinical response and UC severity. Thus, this therapeutic protocol may be useful for managing UC.

Probiotic bacteria regulate intestinal epithelial permeability in experimental ileitis by a TNF-dependent mechanism.

BACKGROUND: We previously showed that the probiotic mixture, VSL#3, prevents the onset of ileitis in SAMP/YitFc (SAMP) mice, and this effect was associated with stimulation of epithelial-derived TNF. The aim of this study was to determine the mechanism(s) of VSL#3-mediated protection on epithelial barrier function and to further investigate the "paradoxical" effects of TNF in preventing SAMP ileitis. METHODS: Permeability was evaluated in SAMP mice prior to the onset of inflammation and during established disease by measuring transepithelial electrical resistance (TEER) on ex vivo-cultured ilea following exposure to VSL#3 conditioned media (CM), TNF or VSL#3-CM + anti-TNF. Tight junction (TJ) proteins were assessed by qRT-PCR, Western blot, and confocal microscopy, and TNFRI/TNFRII expression measured in freshly isolated intestinal epithelial cells (IEC) from SAMP and control AKR mice. RESULTS: Culture with either VSL#3-CM or TNF resulted in decreased ileal paracellular permeability in pre-inflamed SAMP, but not SAMP with established disease, while addition of anti-TNF abrogated these effects. Modulation of the TJ proteins, claudin-2 and occludin, occurred with a significant decrease in claudin-2 and increase in occludin following stimulation with VSL#3-CM or TNF. TNF protein levels increased in supernatants of SAMP ilea incubated with VSL#3-CM compared to vehicle, while IEC-derived TNFR mRNA expression decreased in young, and was elevated in inflamed, SAMP versus AKR mice. CONCLUSIONS: Our data demonstrate that the previously established efficacy of VSL#3 in preventing SAMP ileitis is due to direct innate and homeostatic effects of TNF on the gut epithelium, modulation of the TJ proteins, claudin-2 and occludin, and overall improvement of intestinal permeability.

Antitumor effect of new HER2 peptide vaccination based on B cell epitope.

BACKGROUND: While the benefit of passive immunotherapy is commonly accepted, active immunization may have advantages for the patient's quality of life. We identified a new epitope of Mab CH401 against Her-2/neu extracellular domain (N: 167-175), and evaluated the effect of active immunization of the 20mer peptide containing the epitope (CH401 peptide). MATERIALS AND METHODS: Epitope-mapping was performed using ELISA with Her-2/neu-related multiple antigen peptides (MAP). BALB/c mice were transplanted with Her-2/neu-expressing lymphoma cell line and immunized with the peptides. For monitoring the condition, ELISA and flow cytometry was performed. RESULTS: CH401 peptide induced Her-2/neu-specific IgG antibody. Tumor growth in immunized mice was suppressed and tumor-infiltrating lymphocytes comprised more CD8(+) T-cells, which secreted larger amounts of interleukin-2 after the peptide re-stimulation. CONCLUSION: The new Her-2/neu peptide contained epitopes for CD4(+) and CD8(+) T-cells, which contributes to the suppressive effect on Her-2/neu-expressing tumor cell growth.

A new approach for drug discovery from glycobiology and phage-displayed peptide library technology.

Peptides which mimic functional activities of glycosphingolipids were prepared by a technology of phage-displayed peptide library using monoclonal antibodies against glycosphingolipids. These peptides were named glyco-replica peptides. Peptides prepared with anti-GD1alpha antibody by this technology were found to contain WHW as common motif, and they showed suppressive activity not only on adhesion between hepatic sinusoidal endothelial cells and lymphosarcoma RAW117-H10 cells, but also on metastasis of the tumor cell to the liver and lung. The WHW motif seems to be important to mimic the functional activity of the ganglioside GD1alpha. Next, we prepared GD3-replica peptides using a monoclonal antibody against GD3 (4F6). A peptide, GD3-P4 with highest affinity to 4F6 was used to immunize mice to examine if the mice show their immune response to raise antibodies against GD3. We confirmed the immune response and succeeded in the production of a monoclonal antibody (3D2) against GD3. The monoclonal antibody 3D2 showed specific binding to GD3 on a thin-layer chromatography plate and also melanoma tissues. Interestingly, the amino acid sequence of the CDR regions of light and heavy chains showed high similarity with those of the original GD3 monoclonal antibody (4F6) used for the preparation of GD3-replica peptide. The technology of the phage-displayed peptide library was applied to in vivo bio-panning study using an angiogenesis experimental model. The obtained peptides were found to show strong binding property to the neo-vasculature system and to be quite useful to carry an anti-tumor drug to the tumor tissue. Based on these experimental results, we discuss about some applications of this method to drug discovery.

Efficient gene expression in megakaryocytic cell line using nucleofection.

To clarify the mechanism of platelet production from megakaryocytes, expression of target proteins by gene transfection was examined using various gene delivery techniques. Transfection into hematopoietic cells, including megakaryocytes, by conventional gene delivery techniques such as electroporation and lipofection are known to be difficult. In this study, in addition to electroporation and lipofection, we tested other gene-transfer methods (nucleofection, transfection using inactivated virus envelope, and transferrin-linked cationic polymer) with the green fluorescent protein (GFP) gene into the human megakaryocytic cell line MEG-01. We found that nucleofection, which uses a combination of special electrical parameters and specific solutions, was the best, judging from the expression ratio of GFP-positive cells (approximately 70% of cells) and low toxicity. The efficiency of GFP expression was not related to the amount of pDNA delivered into the MEG-01 cells. To verify the utility of nucleofection, the thrombopoietin (TPO) receptor c-mpl was transfected into MEG-01 cells. Transfected cells showed a higher responsiveness to TPO than mock-transfected MEG-01 cells. We propose that nucleofection is a useful method for transfecting target genes to megakaryocytic cells when addressing the mechanism of platelet production.

Development of human-human hybridoma from anti-Her-2 peptide-producing B cells in immunized NOG mouse.

OBJECTIVE: Numerous monoclonal antibodies have been developed for the purpose of medical treatments, including cancer treatment. For clinical application, the most useful are human-derived antibodies. In this study, we tried to prepare designed antigen-specific antibodies of completely human origin using immunodeficient mouse. METHODS: Nonobese diabetic/severe combined immunodeficient/IL-2 receptor gamma null mouse (NOG) mouse was used to reconstitute the human immune system with umbilical cord blood hematopoietic stem cells (CB-NOG mouse) and to prepare human-derived Her-2-epitope-specific antibodies. Hybridoma lines were prepared by fusing the human myeloma cell line Karpas707H. RESULTS: Serum of immunized NOG mouse contained human-derived immunoglobulin M (IgM) antibodies specific for a short peptide sequence of 20 amino acids, including the epitope peptide of apoptotic Her-2 antibody CH401. Hybridoma lines were successfully prepared with spleen B cells obtained from the immunized CB-NOG mouse. One of these cell lines produced human IgM against the epitope peptide that can recognize surface Her-2 molecule. CONCLUSION: We could produce human-derived IgM antibody against Her-2 epitope peptide in CB-NOG mouse, succeeding in generation of human hybridoma-secreting IgM against a given peptide.

GD3-replica peptides selected from a phage peptide library induce a GD3 ganglioside antibody response.

GD3-replica peptides were obtained from a phage peptide library and an anti-GD3 monoclonal antibody (Mab) (4F6), and anti-GD3 Mabs were generated by immunizing a peptide GD3P4. A Mab, 3D2 was found to recognize GD3 by immunohistochemical approaches. Amino acid analysis of heavy and light chain variable regions of 4F6 and 3D2 showed that the respective chains had the same length, and only a few different amino acid substitutions were found. The present data indicate that the immunogenic GD3P4 is processed in a certain size and exposed on the antigen-presenting cells with a molecular shape quite similar to that of the GD3 epitope in 4F6.