Phylactic role of anti-lipoarabinomannan IgM directed against mannan core during mycobacterial infection in macrophages

Mycobacteria enter host phagocytes, such as macrophages by binding to several receptors on phagocytes. Several mycobacterial species, including Mycobacterium tuberculosis have evolved systems to evade host bactericidal pathways. Lipoarabinomannan (LAM) is an essential mycobacterial molecule for both binding to phagocytes and escaping from bactericidal pathways. Integrin CD11b plays critical roles as a phagocytic receptor and contributes to host defense by mediating both nonopsonic and opsonic phagocytosis. However, the mechanisms by which CD11b-mediated phagocytosis associates with LAM and drives the phagocytic process of mycobacteria remain to be fully elucidated. We recently identified TMDU3 as anti-LAM IgM antibody against the mannan core of LAM. The present study investigated the roles of CD11b and TMDU3 in macrophage phagocytosis of mycobacteria and subsequent bactericidal lysosomal fusion to phagosomes. CD11b knockout cells generated by a CRISPR/Cas9 system showed significant attenuation of the ability to phagocytose non-opsonized mycobacteria and LAM-conjugated beads. Moreover, recombinant human CD11b protein was found to bind to LAM. TMDU3 markedly inhibited macrophage phagocytosis of non-opsonized mycobacteria. This antibody slightly increased the phagocytosis of mycobacteria under opsonized conditions, whereas it significantly enhanced CD11b-mediated bactericidal functions. Taken together, these results show a novel phylactic role of anti-LAM IgM during mycobacterial infection in macrophages.

Identification of anti-lipoarabinomannan antibodies against mannan core and their effects on phagocytosis of mycobacteria by human neutrophils

Mycobacterium tuberculosis (MTB) and M. avium-intracellulare complex (MAC) enter host phagocytes, such as neutrophils through lipoarabinomannan (LAM) binding to pattern-recognition receptors, inducing innate immune responses including phagocytosis. Phagocytosis of mycobacteria by human neutrophils depends on the binding of α(1 → 2)-monomannose branching α(1 → 6)-mannan core of LAM/lipomannan (LM), a common component among mycobacterial species, to lactosylceramide (LacCer)-enriched lipid microdomains. We investigated the binding specificities of several anti-LAM antibodies (Abs) to LAMs/LM and found anti-LAM monoclonal IgMs TMDU3 and LA066 were directed against mannan core. Each IgM showed different binding specificity to mannan core. Confocal and stimulated emission depletion microscopy revealed TMDU3 and LA066 strongly bind to MTB and MAC, respectively. Flow cytometric analysis revealed human neutrophils do not express Dectin-2, DC-SIGN or mannose receptor. Furthermore, neutrophil phagocytosis of mycobacteria was markedly inhibited by TMDU3 and LA066, respectively. Similarly, treatment of each mAb with neutrophils reduced the numbers of intracellular MAC. Together, our results suggest that the interaction of LacCer-enriched lipid microdomains with mannan core and its blocking are therapeutic or diagnostic targets for both TB and non-tuberculous mycobacteria infection.

Multiplicity of Glycosphingolipid-Enriched Microdomain-Driven Immune Signaling

Glycosphingolipids (GSLs), together with cholesterol, sphingomyelin (SM), and glycosylphosphatidylinositol (GPI)-anchored and membrane-associated signal transduction molecules, form GSL-enriched microdomains. These specialized microdomains interact in a cis manner with various immune receptors, affecting immune receptor-mediated signaling. This, in turn, results in the regulation of a broad range of immunological functions, including phagocytosis, cytokine production, antigen presentation and apoptosis. In addition, GSLs alone can regulate immunological functions by acting as ligands for immune receptors, and exogenous GSLs can alter the organization of microdomains and microdomain-associated signaling. Many pathogens, including viruses, bacteria and fungi, enter host cells by binding to GSL-enriched microdomains. Intracellular pathogens survive inside phagocytes by manipulating intracellular microdomain-driven signaling and/or sphingolipid metabolism pathways. This review describes the mechanisms by which GSL-enriched microdomains regulate immune signaling.

Lysophosphatidylglucoside is a GPR55 -mediated chemotactic molecule for human monocytes and macrophages

Neutrophils undergo spontaneous apoptosis within 24-48 h after leaving bone marrow. Apoptotic neutrophils are subsequently phagocytosed and cleared by macrophages, thereby maintaining neutrophil homeostasis. Previous studies have demonstrated involvement of lysophosphatidylglucoside (lysoPtdGlc), a degradation product of PtdGlc, in modality-specific repulsive guidance of spinal sensory axons, via its specific receptor GPR55. In the present study, using human monocytic cell line THP-1 as a model, we demonstrated that lysoPtdGlc induces monocyte/macrophage migration with typical bell-haped curve and a peak at concentration 10^-9 M. Lysophosphatidylinositol (lysoPtdIns), a known GPR55 ligand, induced migration at higher concentration (10^-7 M). LysoPtdGlc-treated cells had a polarized shape, whereas lysoPtdIns-treated cells had a spherical shape. In EZ-TAXIScan (chemotaxis) assay, lysoPtdGlc induced chemotactic migration activity of THP-1 cells, while lysoPtdIns induced random migration activity. GPR55 antagonist ML193 inhibited lysoPtdGlc-induced THP-1 cell migration, whereas lysoPtdIns-induced migration was inhibited by CB₂-receptor inverse agonist. SiRNA experiments showed that GPR55 mediated lysoPtdGlc-induced migration, while lysoPtdIns-induced migration was mediated by CB₂ receptor. Our findings, taken together, suggest that lysoPtdGlc functions as a chemotactic molecule for human monocytes/macrophages via GPR55 receptor, while lysoPtdIns induces random migration activity via CB₂ receptor.

Glycolipids: Linchpins in the Organization and Function of Membrane Microdomains

Membrane microdomains, also called lipid rafts, are areas on membrane enriched in glycolipids, sphingolipids, and cholesterol. Although membrane microdomains are thought to play key roles in many cellular functions, their structures, properties, and biological functions remain obscure. Cellular membranes contain several types of glycoproteins, glycolipids, and other lipids, including cholesterol, glycerophospholipids, and sphingomyelin. Depending on their physicochemical properties, especially the characteristics of their glycolipids, various microdomains form on these cell membranes, providing structural or functional contextures thought to be essential for biological activities. For example, the plasma membranes of human neutrophils are enriched in lactosylceramide (LacCer) and phosphatidylglucoside (PtdGlc), each of which forms different membrane microdomains with different surrounding molecules and is involved in different functions of neutrophils. Specifically, LacCer forms Lyn-coupled lipid microdomains, which mediate neutrophil chemotaxis, phagocytosis, and superoxide generation, whereas PtdGlc-enriched microdomains mediate neutrophil differentiation and spontaneous apoptosis. However, the mechanisms by which these glycolipids form different nano/meso microdomains and mediate their specialized functions remain incompletely understood. This review describes current understanding of the roles of glycolipids and sphingolipids in their enriched contextures on cellular membranes, including their mechanisms of facilitation and regulation of intracellular signaling. This review also introduces new concepts about the roles of glycolipid and sphingolipid-dependent contextures in immunological functions.

Monitoring the build-up of hydrogen polarization for polarized hydrogen-deuteride (HD) targets with nuclear magnetic resonance (NMR) at 17 T

We report on the frozen-spin polarized hydrogen-deuteride (HD) targets for photoproduction experiments at SPring-8/LEPS. Pure HD gas with a small amount of ortho-H₂ (∼0.1%) and a very small amount of para-D₂ (∼0.001%) was liquefied and solidified by liquid helium. The temperature of the produced solid HD was reduced to about 30 mK with a dilution refrigerator. A magnetic field (17 T) was applied to the HD to grow the polarization with the static method. After the aging of the HD at low temperatures in the presence of a high-magnetic field strength for three months, the polarization froze. Almost all ortho-H₂ molecules were converted to para-H₂ molecules. Most remaining para-D₂ molecules were converted to ortho-D₂ molecules. The para-H₂ and ortho-D₂ molecules exhibited weak spin interactions with the HD. If the concentrations of the ortho-H₂ and para-D₂ were reduced appropriately at the beginning of the aging process, the aging time can be shortened. We have developed a new nuclear magnetic resonance (NMR) system to measure the relaxation times (T₁) of the ¹H and ²H nuclei with two frequency sweeps at the respective frequencies of 726 MHz and 111 MHz and succeeded in the monitoring of the polarization build-up at decreasing temperatures from 600 mK to 30 mK at 17 T. Automatic NMR measurements with the frequency sweeps enabled us to omit the use of a manual tuning circuit and to remove magnetic field sweeps with eddy current heat. This technique enables us to optimize the concentration of the ortho-H₂ and to efficiently polarize the HD target within a shortened aging time.

Search for η^{'} Bound Nuclei in the ^{12}C(γ,p) Reaction with Simultaneous Detection of Decay Products

We measured missing mass spectrum of the ^{12}C(γ,p) reaction for the first time in coincidence with potential decay products from η^{'} bound nuclei. We tagged an (η+p) pair associated with the η^{'}N→ηN process in a nucleus. After applying kinematical selections to reduce backgrounds, no signal events were observed in the bound-state region. An upper limit of the signal cross section in the opening angle cosθ_{lab}^{ηp}<-0.9 was obtained to be 2.2  nb/sr at the 90% confidence level. It is compared with theoretical cross sections, whose normalization ambiguity is suppressed by measuring a quasifree η^{'} production rate. Our results indicate a small branching fraction of the η^{'}N→ηN process and/or a shallow η^{'}-nucleus potential.

Differential Cross Section and Photon-Beam Asymmetry for the γ[over →]p → π^{-}Δ^{++}(1232) Reaction at Forward π^{-} Angles for E_{γ}=1.5-2.95 GeV

Differential cross sections and photon-beam asymmetries for the γ[over →]p→π^{-}Δ^{++}(1232) reaction have been measured for 0.7<cosθ_{π}^{c.m.}<1 and E_{γ}=1.5-2.95  GeV at SPring-8/LEPS. The first-ever high statistics cross-section data are obtained in this kinematical region, and the asymmetry data for 1.5<E_{γ}(GeV)<2.8 are obtained for the first time. This reaction has a unique feature for studying the production mechanisms of a pure uu[over ¯] quark pair in the final state from the proton. Although there is no distinct peak structure in the cross sections, a non-negligible excess over the theoretical predictions is observed at E_{γ}=1.5-1.8  GeV. The asymmetries are found to be negative in most of the present kinematical regions, suggesting the dominance of π exchange in the t channel. The negative asymmetries at forward meson production angles are different from the asymmetries previously measured for the photoproduction reactions producing a dd[over ¯] or an ss[over ¯] quark pair in the final state. Advanced theoretical models introducing nucleon resonances and additional unnatural-parity exchanges are needed to reproduce the present data.

Interference Effect between ϕ and Λ(1520) Production Channels in the γp→K^{+}K^{-}p Reaction near Threshold

The ϕ-Λ(1520) interference effect in the γp→K^{+}K^{-}p reaction has been measured for the first time in the energy range from 1.673 to 2.173 GeV. The relative phases between ϕ and Λ(1520) production amplitudes were obtained in the kinematic region where the two resonances overlap. The measurement results support strong constructive interference when K^{+}K^{-} pairs are observed at forward angles but destructive interference for proton emission at forward angles. Furthermore, the observed interference effect does not account for the sqrt[s]=2.1  GeV bump structure in forward differential cross sections for ϕ photoproduction. This fact suggests possible exotic structures such as a hidden-strangeness pentaquark state, a new Pomeron exchange, or rescattering processes via other hyperon states.

Randomized clinical trial of defaecatory function after anterior resection for rectal cancer with high versus low ligation of the inferior mesenteric artery

Background

Defaecatory function is often poor after anterior resection. Denervation of the neorectum following high ligation of the inferior mesenteric artery (IMA) is a possible cause of impaired defaecatory function. The purpose of this randomized clinical trial was to clarify whether the level of ligation of the IMA in patients with rectal cancer affects defaecatory function.

Methods

Between 2008 and 2011, patients who underwent anterior resection for rectal cancer were randomized to receive either high or low ligation of the IMA. The primary endpoint was to demonstrate the superiority of low ligation in terms of defaecatory function.

Results

One hundred patients were enrolled in the study; 51 were randomized to high ligation of the IMA and 49 to low ligation. There were no differences between the groups in terms of clinical data, except tumour stage, which was more advanced in the high-ligation group (P = 0·046). Nor were there any differences in defaecatory function, self-assessment of defaecation, Faecal Incontinence Quality of Life scale or continence score between groups at 3 months and 1 year. The number of harvested lymph nodes was similar. The rate of symptomatic anastomotic leakage was 16 per cent in the high-ligation group and 10 per cent in the low-ligation group (P = 0·415).

Conclusion

The level of ligation of the IMA in patients with rectal cancer did not affect defaecatory function or the incidence of postoperative complications. Registration number: NCT00701012 (http://www.clinicaltrials.gov).

Spin-density matrix elements for γp→K*0Σ+ at Eγ=1.85-3.0 GeV with evidence for the κ(800) meson exchange

The exclusive reaction γp→K(+)π(-)Σ(+) was measured for the first time using linearly polarized photons at beam energies from 1.85 to 2.96 GeV. Angular distributions in the rest frame of the K(+)π(-) system were fitted to extract spin-density matrix elements of the K(*0) decay. The measured parity spin asymmetry shows that natural-parity exchange is dominant in this reaction. This result clearly indicates the need for t-channel exchange of the κ(800) scalar meson.

Near-threshold Lambda(1520) production by the gamma(p)-->K{+}Lambda(1520) reaction at forward K+ angles

Differential cross sections and photon-beam asymmetries for the gamma(p)-->K{+}Lambda(1520) reaction have been measured with linearly polarized photon beams at energies from the threshold to 2.4 GeV at 0.6<cos(theta){c.m.}{K}<1. A new bump structure was found at W approximately 2.11 GeV in the cross sections. The bump is not well reproduced by theoretical calculations introducing a nucleon resonance with J<or=3/2. This result suggests that the bump might be produced by a nucleon resonance possibly with J>or=5/2 or by a new reaction process, for example, an interference effect with the phi photoproduction having a similar bump structure in the cross sections.

Near-threshold photoproduction of Lambda(1520) from protons and deuterons

Photoproduction of Lambda(1520) with liquid hydrogen and deuterium targets was examined at photon energies below 2.4 GeV in the SPring-8 LEPS experiment. For the first time, the differential cross sections were measured at low energies and with a deuterium target. A large asymmetry of the production cross sections from protons and neutrons was observed at backward K+/0 angles. This suggests the importance of the contact term, which coexists with t-channel K exchange under gauge invariance. This interpretation was compatible with the differential cross sections, decay asymmetry, and photon beam asymmetry measured in the production from protons at forward K+ angles.

Phase I/II study of concurrent chemoradiotherapy for localized nasal NK/T-cell lymphoma: Final results of JCOG0211

8549

Background: Nasal NK/T-cell lymphoma is rare and its standard therapy has not been established. Tumor cells express P-glycoprotein concerning multi-drug resistance (MDR). Anthracycline-containing chemotherapy is not effective and %2-yr overall survival (OS) of radiotherapy (RT) alone is only 45%. Methods: To explore a more effective treatment for localized nasal NK/T-cell lymphoma, we conducted a phase I/II study of concurrent chemoradiotherapy consisted of 50 Gy of RT and 3 courses of DeVIC [carboplatin (CBDCA), etoposide (ETP), ifosfamide (IFM), dexamethasone (DMS)]. Patients (Pts) with newly-diagnosed, localized (IE & contiguous IIE with cervical node involvement) diseases, 20–69 years of age and PS 0–2 were eligible. The 3-D conformal RT planning was required to cover adequately target volumes (2 cm margin to gross tumor, entire nasal cavities and nasopharynx) and to minimize doses to organs at risk. Primary endpoint of the phase II portion was 2-yr OS and the enrollment of 24 pts to the phase II portion was planned. Based on the results of the phase I portion (ASH 2005, #2685), 2/3-dose of DeVIC (CBDCA 200mg/m2 d1 IV, ETP 67mg/m2 d1–3 IV, IFM 1.0g/m2 d1–3 IV, DMS 40mg/body d1–3 IV; every 3 wks) was applied for the phase II portion. RT quality assurance review confirmed no protocol violation (ASTRO 2008, #2682). Results: From Sep 2003 to Dec 2006, 33 pts were enrolled in the phase I/II study. 27 pts evaluated in the phase II portion showed the following features: age 21–68 yrs (median 56), M:F=17:10, stage IE 18, stage IIE 9, B symptom (+) 10, elevated serum LDH 5, PS2 2. With a median follow-up of 32 months (range, 24–62), %2-yr OS was 78% (95% CI, 57–89). Of 26 pts evaluable for response, 20 achieved CR, 1 PR, 2SD, and 3PD. %CR and %ORR were 77% (95% CI, 56–91) and 81%, respectively. The most common grade 3 non-hematologic toxicities were mucositis due to RT (30%) and infection (30%). Grade 4 hyponatremia and dermatitis due to RT were observed in each 1 pt. No treatment-related death was observed. Conclusions: Concurrent chemoradiotherapy using MDR-non-related agents and ETP is a safe and effective treatment for localized nasal NK/T-cell lymphoma, providing the basis for subsequent studies.

No significant financial relationships to disclose.

Phase II study of cladribine with rituximab (R-2-CdA) therapy in patients with relapsed indolent B-cell non-Hodgkin's lymphoma

e19501

Background: Although cladribine has been reported to be one of active purine analogs against indolent B-cell non-Hodgkin's lymphoma (B-NHL), there are few reports of combination usage of cladribine and rituximab. We conducted a multicenter phase II study to investigate efficacy and toxicity of cladribine with rituximab (R-2-CdA) therapy for relapsed indolent B-NHL. Methods: Eligibility criteria were as follows: relapsed pts with indolent B-NHL from systemic chemotherapy, ages less than 75 years; PS 0–2 by ECOG's scale. Patients received 0.09mg/kg of cladribine intravenously (2 hrs infusion) on days 1 to 5 and 375mg/m2 of rituximab intravenously on days 1 and 15, every 4 weeks, for a total of 4 cycles. Primary endpoint was overall response rate (ORR). Secondary endpoints were % complete response (%CR), 2 years progression free survival (2-y PFS), and 2 years overall survival (2-y OS). Results: A total of 20 out of 45 planned patients were enrolled and received R-2-CdA therapy from Apr 2005 to Jul 2007. Their median age was 58.5 (42–72), and the median number of prior regimens was 2 (1–3). Histologies included 16 follicular lymphomas, 2 MALT lymphomas, 1 nodal marginal B cell lymphoma, and 1 lymphoplasmacytic lymphoma. Fifteen pts (75%) were previously treated with rituximab. The ORR was 90% with 70% of % CR. Median PFS was 20.1 months (5.6–32.9 months) at a median follow-up time of 27 months. 2-y PFS and 2-y OS were 63.2% (95%CI, 28.1–67.8%), and 89.5% (95%CI, 69.8–97.2%), respectively. Severe neutropenia and thrombocytopenia of grade 3 or 4 were observed in 15% and 10% respectively. Conclusions: R-2CdA therapy was demonstrated to have high activity with durable PFS and acceptable toxicity in relapsed indolent B-NHL, even if patients were previously treated with rituximab. Although a large-scaled further trial remains to be needed, R-2-CdA therapy could be a good option of salvage therapy in relapsed indolent B-NHL.

No significant financial relationships to disclose.

Cross sections and beam asymmetry for K;{+}Sigma;{*-} photoproduction from the deuteron at E_{gamma}=1.5-2.4 GeV

The Sigma(1385) resonance, or Sigma;{*}, is well known as part of the standard baryon decuplet with spin J=3/2. Measurements of the reaction gammap-->K;{+}Sigma;{*0} are difficult to extract due to overlap with the nearby Lambda(1405) resonance. However, the reaction gamman-->K;{+}Sigma;{*-} has no overlap with the Lambda(1405) due to its charge. Here we report the first measurement of cross sections and beam asymmetries for photoproduction of the Sigma;{*-} from a deuteron target. The cross sections at forward angles range from 0.4 to 1.2 mub, with a broad maximum near E_{gamma} approximately 1.8 GeV. The beam asymmetries are negative, in contrast with positive values for the gamman-->K;{+}Sigma;{-} reaction.

Differential cross section and photon-beam asymmetry for the gamma n --> K+ Sigma- reaction at E gamma = 1.5-2.4 GeV

Differential cross sections and photon-beam asymmetries have been measured for the gamma n --> K+ Sigma- and gamma p --> K+Sigma0 reactions separately using liquid deuterium and hydrogen targets with incident linearly polarized photon beams of E gamma = 1.5-2.4 GeV at 0.6 < cos ThetacmK< 1. The cross section ratio of sigma K+ Sigma-/sigma K+ Sigma0, expected to be 2 on the basis of the isospin 1/2 exchange, is found to be close to 1. For the K+ Sigma- reaction, large positive asymmetries are observed, indicating the dominance of K* exchange. The large difference between the asymmetries for the K+ Sigma- and K+ Sigma0 reactions cannot be explained by simple theoretical considerations based on Regge model calculations.

Effectiveness and new safety profile of rasburicase (urate oxidase) in Japanese patients with malignant lymphoma and acute leukemia in phase II study (ARD5290)

8566

Background: Rasburicase (RAS) for the prevention of tumor lysis syndrome (TLS) populations at high risk, and for the treatment of hyperuricemia (HU) has obtained approvals in most countries in the world except in Japan. Thus, we conducted licensing phase II study of RAS with primary endpoint of overall efficacy response (ER) rate. We report efficacy and the new safety profile of only RAS administration prior to chemotherapy. Methods: Fifty patients (pts) with ML and/or AL, were administered RAS for 5 days using two dose-levels (0.15 mg/kg/day or 0.20 mg/kg/day). Chemotherapies were started from 4 to 24 hours after RAS treatment. ER was defined as keeping plasma uric acid level 7.5mg/dL by 48 hr after the start of first RAS infusion and lasting until 24 hr after the start of final (Day5) RAS infusion. Results: The overall ER rate was 98%. 49 pts (98%) completed 5 days of treatment. Both doses provided equally effective reduction of uric acid under the study conditions. Seven drug-related adverse events of grade 1 or 2 by NCI-CTC occurred in 6 pts during using only RAS (before first chemotherapy). ‘Hypersensitivity’ occurred in 3 pts, and ‘rash’, ‘anorexia’, ‘application site pain’, and ‘pyrexia’ occurred in 1 patient each. No grade 3 or 4 adverse events were reported. Only five pts (10%) had anti-RAS antibodies by Day29. Conclusions: RAS has proved to be highly effective with a good safety profile including the new safety one as single agent without chemotherapy. Although both two levels were effective, level of 0.20 mg/kg seems to be an optimal dose because RAS was effective against serious cases of HU in this level. The presence of anti-RAS antibodies was very low suggesting that the possibility for retreatment maybe possible.

No significant financial relationships to disclose.

Quality assurance of radiotherapy in the Japan Clinical Oncology Group trial 0211 concerning concurrent chemoradiotherapy for localized nasal NK/T-cell lymphoma: The individual case review

17561

Background: It is challenging to conduct a high quality multi-institutional clinical trial for localized nasal NK/T-cell lymphoma due to the anatomical complexity and its rarity. The purpose of this study was to evaluate the compliance with protocol guidelines in concurrent chemoradiotherapy for this disease among radiotherapy institutions participating in a multi-center phase I/II JCOG trial 0211. Methods: The treatment consisted of radiotherapy 50 Gy and 3 cycles of DeVIC chemotherapy [carboplatin, etoposide, ifosfamide, dexamethasone] (Yamaguchi M, et al.: Proc ASH, 2005). CT-based three-dimensional treatment planning was required to cover adequately target volumes and to minimize doses to organs at risk such as the eyes, the brain stem and the spinal cord. Patient data were sent to the review center after the treatments have been finalized. The following parameters were evaluated by the quality assurance review board: treatment records and charts; simulation films; portal images; prescribed dose; dose fractionation and overall treatment time; dose distributions; and dose to risk organs. Results: At the time of phase I analysis, 10 patients were enrolled in this study. In 2 of 10 cases, process of treatment planning was not available. There was no protocol violation. Major deviations were identified as follows: Delineation of clinical target volume (< 2 cm from the edge of the gross tumor volume at any direction), 2/10; dose distribution (not covered by 90%-115% isodose line), 1/10; and dose to optic chiasm (>40 Gy), 1/10. All cases were compliant in prescribed dose, dose fractionation, and overall treatment time. In the last 4 of 10 cases, attending radiation oncologists at the participating institutions were contacted by the radiation oncology study chair and they discussed the treatment planning just after patient enrollment. These 4 cases were all protocol compliant compared to 6 cases with 4 major deviations. Conclusions: Individual case review is essential in a multi-center clinical trial to keep enrolled cases protocol compliant and minimize inter-institutional variations. We expect that our quality assurance program will maintain the quality of the JCOG trial 0211.

No significant financial relationships to disclose.

Expression of CD90 on keratinocyte stem/progenitor cells

BACKGROUND

The identification and purification of keratinocyte stem cells (KSCs) that are capable of self-renewal and maintenance of differentiating cell populations could contribute both to our understanding of the biology of these cells, and to significant clinical applications, such as the culturing of keratinocytes for transplantation to severe burn wounds. Here, we report the detection of CD90(+) cells in cultured normal human epidermal keratinocytes and adult skin.

OBJECTIVES

To investigate the biological function of CD90(+) and CD90(-) keratinocytes.

METHODS

CD90(+) and CD90(-) keratinocytes were purified from adult skin and cultured keratinocytes using fluorescent activated cell sorting, and their biological abilities were analysed using both in vitro and in vivo assays.

RESULTS

Flow cytometry (FCM) analysis identified approximately 18% of post-primary neonatal keratinocytes as CD90(+). However, during expansion of the culture, the expression level of CD90 rapidly decreased to about 2.5% at passage 10, while most of the keratinocytes maintained expression of alpha6 integrin. Purified CD90(+) keratinocytes demonstrated a sixfold higher cell growth rate than CD90(-) cells and the ability to form large (over 3 mm in diameter) colonies. We then quantitatively evaluated both populations using a previously described in vivo human epidermal cyst formation assay. Enhanced green fluorescent protein (EGFP)-labelled CD90(+) or CD90(-) keratinocytes were subcutaneously injected into nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice. Six weeks after transplantation, EGFP(+) cell clusters in human epidermal cysts were evaluated using image analysis software. EGFP(+) cell cluster areas in the basal layer, derived from EGFP(+) CD90(+) cells, were eightfold larger than clusters of EGFP(+) CD90(-) cells. Furthermore, immunohistochemical staining and FCM analysis indicated that CD90 was expressed in most of the basal layer of the normal human epidermis.

CONCLUSIONS

These results indicated that CD90 is a useful marker for the detection of human KSC-enriched populations in cultured human keratinocytes.

Effect of incadronate on proliferation of mesenchymal tumor cells with or without activated Ras mutation

The present investigation examined the effect of bisphosphonates on six mesenchymal tumor cell lines and the mechanisms of inhibition of tumor cell proliferation. HT-1080, a fibrosarcoma cell line that exhibits increased Ras activity due to a mutation of the Ras gene, demonstrated significantly reduced tumor cell proliferation upon treatment with incadronate. The other cell lines, however, which lack mutation of the Ras gene, showed no influence upon treatment with incadronate. Autoradiography demonstrated no difference in the uptake of 3H-labelled incadronate between susceptible and unaffected cells. The anti-proliferation of HT-1080 was reversed by the addition of geranylgeranyl pyrophosphate. Etidronate exhibited no influence on all tested cell lines. On the basis of these data, we hypothesized that incadronate inhibits the mevalonate pathway and blocks oncogenic Ras signaling. In an effort to confirm this hypothesis, the influence of incadronate on an oncogenic Ras transfected BALB/3T3 cell line (Bhas 42) and a parental BALB/3T3 cell line were compared. The parental BALB/3T3 cells showed slight inhibition upon treatment with incadronate, however, the proliferation of Bhas 42 cells was significantly reduced. These results suggest that incadronate suppresses oncogenic Ras-activated mesenchymal tumors through the inhibition of Ras signaling pathways.

Congenital dermatofibrosarcoma protuberans with fibrosarcomatous and myxoid change

This report describes a case of congenital dermatofibrosarcoma protuberans (DFSP) with fibrosarcomatous (FS) and myxoid areas. Immunohistochemical results showed that tumour cells in ordinary DFSP areas were diffusely positive for CD34, whereas in the FS and myxoid areas, few tumour cells were positive for this antigen. Ki-67 positive tumour cell numbers were greater in the FS (11.8%) and myxoid areas (19.8%) relative to ordinary DFSP areas (2.2%). Reverse transcription polymerase chain reaction and sequence analysis showed the presence of an identical COL1A1-PDGFB fusion transcript in ordinary DFSP (plaque-like area), FS, and myxoid areas of DFSP. These results indicate that the three components of DFSP have a common histogenesis. This study documents the first application of gene analysis involving the myxoid area of DFSP.

Phase I and pharmacokinetic study of oral fludarabine phosphate in relapsed indolent B-cell non-Hodgkin's lymphoma

BACKGROUND

The primary objective of this study was to investigate the tolerability, efficacy and pharmacokinetic profile of oral fludarabine phosphate in relapsed patients with indolent B-cell non-Hodgkin's lymphoma (B-NHL).

PATIENTS AND METHODS

Patients received fludarabine phosphate orally for 5 days, for a total of one to three cycles. Tolerability was assessed using the National Cancer Institute Common Toxicity Criteria. Efficacy was assessed using the International Workshop Criteria for NHL. Pharmacokinetic samples were taken on day 1 and day 5 of the first treatment cycle.

RESULTS

Twelve patients were enrolled. One patient at 40 mg/m2/day developed grade 4 hyperuricemia. At 50 mg/m2/day, one patient developed grade 3 febrile neutropenia and grade 4 leukopenia, and another patient showed lasting grade 4 neutropenia. Most common toxicities included grade 3 or 4 lymphopenia (83%), leukopenia (50%) and neutropenia (50%). All the toxicities were reversible. The overall response rate was 67%. The AUC0-24h values on day 5 indicated a dose-dependent increase in systemically available 2-fluoro-arabinofuranosyl-adenine (2F-ara-A).

CONCLUSIONS

Oral fludarabine phosphate is safe and effective for relapsed patients with indolent B-NHL. The dose of 40 mg/m2/day is recommended for a following pivotal phase II study.

Near-threshold diffractive psi-meson photoproduction from the proton

Photoproduction of a phi meson on protons was studied by means of linearly polarized photons at forward angles in the low-energy region from threshold to Egamma = 2.37 GeV. The differential cross sections at t = -|t|min do not increase smoothly as Egamma increases but show a local maximum at around 2.0 GeV. The angular distributions demonstrate that phi mesons are photoproduced predominantly by helicity-conserving processes, and the local maximum is not likely due to unnatural-parity processes.

Increased frequency of the angiotensin-converting enzyme gene D-allele is associated with noninfectious pulmonary dysfunction following allogeneic stem cell transplant

Noninfectious pulmonary dysfunction (NIPD) is a common and often fatal complication associated with allogeneic hematopoietic stem cell transplantation (HSCT). An insertion/deletion polymorphism in the angiotensin-converting enzyme (ACE) gene has been extensively studied in relation to cardiovascular and renal disease, and lung fibrosis. In pulmonary fibrosis, D-allele frequency is significantly higher than in the control population. We hypothesized that a similar mechanism exists between post-HSCT NIPD and pulmonary fibrosis in the absence of HSCT. We retrospectively analyzed the incidence of NIPD and the ACE genotype polymorphism in 118 Japanese patients who underwent HSCT from HLA-identical sibling donors. NIPD occurred in 17 cases. Deletion/deletion genotype carriers were more common in the NIPD group than in the other 101 patients (41.2 vs 11.9%; hazard ratio, 5.19; 95% confidence interval, 1.67-16.21). There were no significant relationships between the clinical characteristics of patients and the development of NIPD. These findings suggest that the ACE genotype is associated with the development of NIPD following HSCT. This study is the first to report the relationship between genetic background and NIPD.

Isolation and transplantation of highly purified autologous peripheral CD34+ progenitor cells: purging efficacy, hematopoietic reconstitution in non-Hodgkin's lymphoma (NHL): results of Japanese phase II study

The purging efficacy of positive selection of autologous CD34+ PBSC with a clinical scale method of magnetic-activated cell sorting system (CliniMACS) was investigated in 48 patients with non-Hodgkin's lymphoma (NHL). The median purity and recovery rate of the CD34+ cells post-selection were 93.3% (range 32.6-99.3) and 72.2% (range 20.5-309.8), respectively. The real-time PCR method to detect the patient-specific monoclonal immunoglobulin heavy chain gene rearrangement (minimal residual tumor; MRT) and CD19 and CD20 positivities were used for the detection of contaminating NHL cells before and after CD34+ selection. After selection, the median (range) depletion rate of MRT was 2.53 (1.52-4.78) log, and that of CD19+ cell and CD20+ cell was 2.46 (0.74-3.64) log and 2.32 (0.40-4.01) log, respectively. In 41 patients, high-dose chemotherapy was performed, followed by the transplantation of the isolated CD34+ cells. Rapid neutrophil recovery as well as platelet recovery was seen with a median time to reach 0.5 x 10(9)/l neutrophils of 10 days (range 8-13) and 20 x 10(9)/l platelets of 14 days (range 10-34), respectively. The present study demonstrated that CliniMACS is a highly effective positive selection method and a high purging efficacy could be obtained without compromising the hematopoietic reconstitution capacity of the graft in NHL patients undergoing high-dose chemotherapy.

Extracorporeal irradiated autogenous osteochondral graft

We examined osteochondral autografts, obtained at a mean of 19.5 months (3 to 48) following extracorporeal irradiation and re-implantation to replace bone defects after removal of tumours. The specimens were obtained from six patients (mean age 13.3 years (10 to 18)) and consisted of articular cartilage (five), subchondral bone (five), external callus (one) and tendon (one). The tumour cells in the grafts were eradicated by a single radiation dose of 60 Gy. In three cartilage specimens, viable chondrocytes were detected. The survival of chondrocytes was confirmed with S-100 protein staining. Three specimens from the subchondral region and a tendon displayed features of regeneration. Callus was seen at the junction between host and irradiated bone.

Treatment of pathological fracture of the femur due to diffuse haemangioma in the lower limb

We describe two patients with a diffuse haemangioma of the lower limb complicated by pathological fracture of the femoral shaft, one of whom was treated by a bone graft and immobilisation in a cast, and the other by external fixation and injection of bone marrow. A review of the literature identified difficulty in control of bleeding and obtaining bony union.

Japanese multicenter phase II and pharmacokinetic study of rituximab in relapsed or refractory patients with aggressive B-cell lymphoma

BACKGROUND

To evaluate the efficacy and feasibility of rituximab monotherapy in Japanese patients with relapsed or refractory aggressive B-cell lymphoma.

PATIENTS AND METHODS

Sixty-eight patients were treated with rituximab at 375 mg/m(2) by eight consecutive weekly infusions. Pretreatment variables affecting overall response rate (ORR) and progression-free survival (PFS) and the relationship between pharmacokinetic parameters and efficacy were analyzed.

RESULTS

The ORRs of 68 enrolled patients and 57 eligible patients were 35% [95% confidence interval (CI) 24% to 48%] and 37% (95% CI 25% to 51%), respectively. Median PFS of 53 evaluable patients was 52 days, whereas time to progression of 21 eligible responders was 245 days. Mild to moderate infusion-related toxicities were observed frequently at the first infusion, but all of them were reversible. Elevated lactate dehydrogenase (LDH) and refractoriness to prior chemotherapy were unfavorable factors affecting ORR and PFS (P <0.01). Serum trough levels of rituximab and area under the concentration-time curve for responders were higher than for non-responders (P <0.05).

CONCLUSIONS

Eight consecutive weekly infusions of rituximab have significant anti-lymphoma activity for relapsed or refractory aggressive B-cell lymphoma. Several pretreatment variables and serum rituximab levels are useful for predicting its efficacy.