Rapid isolation of intrabody candidates by using an optimized non-immune phage antibody library

Phage antibody library is a promising tool for rapidly creating in vitro single-chain Fv (scFv) antibodies to various antigens. The scFv can also act like a subcellularly-expressed antibody, known as intrabody, and can either be used as a novel research tool or used efficiently for targeted molecular therapy. However, there are only a few existing reports about the successful expression of scFvs as functional antibodies in the cell, mainly because poor quality scFv phage antibody libraries were used to isolate the intrabody clones. The aim of this study was to isolate intrabody-forming scFv clones from the nonimmune scFv phage antibody library we have generated. Using this library, we isolated a scFv clone against the apoptosis-related intracellular protein Bid in two weeks. To evaluate the intrabody-forming quality of this anti-Bid scFv clone, we expressed it in cultured mammalian cells after fusing it with the fluorescent protein Venus. The expression of the soluble form of anti-Bid scFv-Venus fusion protein was confirmed by fluorescence microscopy analysis. These results show that our scFv phage library is not only optimized for antibody production but can also be used to efficiently generate intrabodies.

The specific effect of 2-methoxyestradiol on lymphatic vascular endothelial cells

Lymphatic metastasis of tumors is one of the most important prognostic factors and provides valuable information for decisions on appropriate surgical protocols. Recent studies have demonstrated that lymphangiogenesis of lymphatic vascular endothelial cells into tumors is a key event in lymphatic metastasis. Therefore, control of lymphangiogenesis is a promising strategy for treatment or prevention of tumor metastasis and lymphatic disorders. However, mechanisms of lymphangiogenesis or its specific inhibition are not well-understood. In this study we examined effects of various types of signaling inhibitors on tube formation in human lymphatic microvascular endothelial cells (LECs) and blood microvascular endothelial cells (BECs) in vitro. We found that tube formation of LECs was specifically inhibited by 2-methoxyestradiol (2ME). This observation is of potential benefit in understanding the molecular mechanism of lymphangiogenesis. Furthermore, 2ME could therefore offer specific protection against lymphatic metastasis and lymphangiogenesis-related diseases.

[Ross operation and mitral valve repair for active infective endocarditis]

A 17-year-old woman was admitted to our hospital for the treatment of infective endocarditis. Echocardiography showed vegetation on the aortic valve and the anterior leaflet of the mitral valve. Because of the evidence of multiple embolisms including coronary, splenic, and right brachial arteries, emergency Ross operation was performed using Prima PLUS stentless valve for reconstruction of the right ventricular outflow tract and so was mitral valve repair with autologous pericardial patch. Although cerebral hemorrhage occurred postoperatively, she recovered well without any neurological deficit. She was in good condition without any anticoagulation therapy 12 months after surgery. The Ross operation and mitral valve repair are useful for the treatment of aortic and mitral infective endocarditis, especially in young women with the potential of future pregnancy and labor.

Effect of protein properties on display efficiency using the M13 phage display system

The M13 phage display system is a powerful technology for engineering proteins such as functional mutant proteins and peptides. In this system, it is necessary that the protein is displayed on the phage surface. Therefore, its application is often limited when a protein is poorly displayed. In this study, we attempted to understand the relationship between a protein's properties and its display efficiency using the well-known pIII and pVIII type phage display system. The display of positively charged SV40 NLS and HIV-1 Tat peptides on pill was less efficient than that of the neutrally charged RGDS peptide. When different molecular weight proteins (1.5-58 kDa) were displayed on pIII and pVIII, their display efficiencies were directly influenced by their molecular weights. These results indicate the usefulness in predicting a desired protein's compatibility with protein and peptide engineering using the phage display system.

Majorana bound state in rotating superfluid 3He-A between parallel plates

A concrete and experimentally feasible example for testing the putative Majorana zero-energy state bound in a vortex is theoretically proposed for a parallel plate geometry of superfluid 3He-A phase. We examine the experimental setup in connection with ongoing rotating cryostat experiments. The theoretical analysis is based on the well-established Ginzburg-Landau functional, supplemented by microscopic calculations of the Bogoliubov-de Gennes equation, both of which allow the precise location of the parameter regions of the Majorana state to be found in realistic situations.

Chimerism and T-cell receptor repertoire analysis after unrelated cord blood transplantation with a reduced-intensity conditioning regimen following autologous stem cell transplantation for multiple myeloma

A 65-year-old Japanese male was diagnosed as multiple myeloma with Bence Jones kappa type, clinical stage IIIA. His disease status reached partial remission after chemotherapy. Thereafter, he received tandem transplantation, consisting of high-dose chemotherapy with autologous stem cell transplantation (ASCT), followed by unrelated cord blood transplantation (U-CBT). U-CBT with a reduced-intensity conditioning regimen (RI-CBT) was performed in August 2003. HLA mismatch between the patient and the CBT donor was present at two serological loci (B and DR). A total nucleated CBT cell dose of 2.45 x 10(7)/kg body weight was infused on day 0. Graft-vs.-host disease (GVHD) prophylaxis consisted of cyclosporine A and short-term methotrexate. Neutrophil engraftment (>0.5 x 10(9)/l) was obtained on day 46. He developed positive cytomegalovirus antigenemia, grade II acute GVHD involving skin and liver, varicella-zoster virus infection, septic shock, hemorrhagic cystitis caused by adenovirus and acute hepatitis B virus infection after U-CBT. We retrospectively analyzed T-cell receptor (TCR) repertoire diversity and found that TCR repertoire diversity decreased continuously after U-CBT. Therefore, low-TCR repertoire diversity in this patient appears to be associated with various infections caused by immunodeficiency.

Last resort for renal transplant recipients, 'restored kidneys' from living donors/patients

Because of the grave shortage of deceased kidney allografts in Japan, we have embarked on a new source of organs, 'Restored kidneys' from living patients. From January 1991 through September 2006, 42 kidneys (eight benign pathology, eight small renal cancers, eight ureteral cancers, six aneurysms, eight severe nephrotic syndrome from four patients and four ureteral stenosis) were obtained from 38 patients/donors after extensive discussion of treatment modalities and risks. All patients/donors agreed to undergo total nephrectomy. The lesions were removed/repaired ex vivo on the back table, then transplanted. All recipients were notified of all possible risks including donor disease recurrence. One, 5 and 10-year patient survival rates of restored transplant patients were 92.9%, 79.3% and 63.8%, respectively. One, 5 and 10-year graft survival rates of restored kidney transplant patients were 78.6%, 51.8% and 42.7%, respectively. There were no recurrences of small renal cell carcinomas. There was one recurrence of ureteral cancer in the transplanted kidney 15 months after operation. In countries where deceased donors are scarce, such as Japan, the restored kidneys can be a last resort for renal allografts.

Hydrovenous Disorder in Vein of Galen Aneurysmal Dilatation: Special Focus on Tonsilar Prolapse

We analyzed five cases of vein of Galen aneurysmal dilatation (VGAD) and 12 cases of vein of Galen aneurysmal malformation (VGAM) using sagittal T1-weighted images. Tonsilar prolapse (TP) was confirmed in three cases, which were all VGAD. Two of these cases were treated by endovascular procedures. In one of these two cases, elevation of TP was observed after intervention. There were no signs of TP in the control group of 12 VGAMs. Venous hypertension interferes with cerebrospinal fluid (CSF) resorption resulting in increased brain fluid. TP frequently develops in high flow AVFs and is reversible if therapeutic intervention is performed by an experienced clinical team when appropriately indicated. We consider that TP in VGAD is mainly the result of cerebellar swelling due to chronic venous hypertension.

Comparative study on transduction and toxicity of protein transduction domains

BACKGROUND AND PURPOSE

Protein transduction domains (PTDs), such as Tat, antennapedia homeoprotein (Antp), Rev and VP22, have been extensively utilized for intracellular delivery of biologically active macromolecules in vitro and in vivo. There is little known, however, about the relative transduction efficacy, cytotoxicity and internalization mechanism of individual PTDs.

EXPERIMENTAL APPROACH

We examined the cargo delivery efficacies of four major PTDs (Tat, Antp, Rev and VP22) and evaluated their toxicities and cell internalizing pathways in various cell lines.

KEY RESULTS

The relative order of the transduction efficacy of these PTDs conjugated to fluorescein was Rev>Antp>Tat>VP22, independent of cell type (HeLa, HaCaT, A431, Jurkat, MOLT-4 and HL60 cells). Antp produced significant toxicity in HeLa and Jurkat cells, and Rev produced significant toxicity in Jurkat cells. Flow cytometric analysis demonstrated that the uptake of PTD-fluorescein conjugate was dose-dependently inhibited by methyl-beta-cyclodextrin, cytochalasin D and amiloride, indicating that all four PTDs were internalized by the macropinocytotic pathway. Accordingly, in cells co-treated with 'Tat-fused' endosome-disruptive HA2 peptides (HA2-Tat) and independent PTD-fluorescent protein conjugates, fluorescence spread throughout the cytosol, indicating that all four PTDs were internalized into the same vesicles as Tat.

CONCLUSIONS AND IMPLICATIONS

These findings suggest that macropinocytosis-dependent internalization is a crucial step in PTD-mediated molecular transduction. From the viewpoint of developing effective and safe protein transduction technology, although Tat was the most versatile carrier among the peptides studied, PTDs should be selected based on their individual characteristics.

Field-angle-dependent specific heat measurements and gap determination of a heavy fermion superconductor URu2Si2

To identify the superconducting gap structure in URu2Si2, we perform field-angle-dependent specific heat measurements for the two principal orientations in addition to field rotations, and a theoretical analysis based on microscopic calculations. The Sommerfeld coefficient gamma(H)'s in the mixed state exhibit a distinctly different field dependence. This comes from point nodes and the substantial Pauli paramagnetic effect of URu2Si2. These two features combined give rise to a consistent picture of superconducting properties, including a possible first order transition of Hc2 at low temperatures.

Role of Tyr residues on the protein surface of cationic cell-wall-peroxidase (CWPO-C) from poplar: potential oxidation sites for oxidative polymerization of lignin

It was previously reported that an unique peroxidase isoenzyme, cationic cell-wall-bound peroxidase (CWPO-C), from poplar callus oxidizes sinapyl alcohol, ferrocytochrome c and synthetic lignin polymers, unlike other plant peroxidases. Here, the catalytic mechanism of CWPO-C was investigated using chemical modification and homology modeling. The simulated CWPO-C structure predicts that the entrance to the heme pocket of CWPO-C is the same size as those of other plant peroxidases, suggesting that ferrocytochrome c and synthetic lignin polymers cannot interact with the heme of CWPO-C. Since Trp and Tyr residues are redox-active, such residues located on the protein surface were predicted to be active sites for CWPO-C. Modification of CWPO-C Trp residues did not suppress its oxidation activities toward guaiacol and syringaldazine. On the other hand, modification of CWPO-C Tyr residues using tetranitromethane strongly suppressed its oxidation activities toward syringaldazine and 2,6-dimethoxyphenol by 90%, respectively, and also suppressed its guaiacol oxidation activity to a lesser extent. Ferrocytochrome c was not oxidized by Tyr-modified CWPO-C. These results indicate that the Tyr residues in CWPO-C mediate its oxidation of syringyl compounds and high-molecular-weight substrates. Homology modeling indicates that Tyr-177 and Tyr-74 are located near the heme and exposed on the protein surface of CWPO-C. These results suggest that Tyr residues on the protein surface are considered to be important for the oxidation activities of CWPO-C with a wide range of substrates, and potentially unique oxidation sites for the plant peroxidase family.

Creation of a novel cell penetrating peptide, using a random 18mer peptides library

Cell penetrating peptides (CPPs) have drawn attention as carriers for intracellular drug delivery. It is commonly believed that TAT peptide is the best carrier among the existing CPPs due to its high translocational activity. Despite considerable research, the cellular uptake mechanism of TAT peptide remains unclear. Additionally, the transduction efficiency of TAT peptide is insufficient for use in intracellular therapy. In this study, we attempted to identify novel CPPs from a random 18mer peptide library using a phage display system. To isolate novel CPPs more effectively, PSIF (protein synthesis inhibition factor) was used with the screening system. Consequently, we isolated 7 novel CPPs from the library and determined by flow cytometry and confocal laser microscopy that these CPPs were taken up into cells. Once the cellular uptake pathway of these CPPs has been determined, it may be possible to use them for intracellular therapy.

Steroid 9α-Hydroxylation during Testosterone Degradation by RestingRhodococcus equiCells

The conversion pathway of testosterone to androst-4-ene-3,17-dione and 9alpha-hydroxy androstane metabolites, 9alpha-hydroxyandrost-4-ene-3,17-dione and 9alpha,17beta-dihydroxyandrost-4-en-3-one was proposed for the ring degradation in steroids by a minimal liquid medium (NMMP)-dispersed Rhodococcus equi ATCC 14887. The microorganism produced 9alpha-hydroxy androstane metabolites from testosterone at high conversion ratio without the addition of ring degradation inhibitory agents. Several NMMP-based media showed the similar effect on the microbial transformation, in which the respective molar yields of 9alpha-hydroxyandrost-4-ene-3,17-dione and 9alpha,17beta-dihydroxyandrost-4-en-3-one were approx. 3 to 47% and approx. 3 to 11%, respectively, whereas nutrient broth, a rich medium, basically showed no accumulation. On the basis of this evidence, magnesium sulfate and casamino acids among the components of NMMP were found to compromise the determinant for the production of the 9alpha-hydroxy androstane metabolites without appreciable decomposition of the steroid ring system.

Immunostaining of thymidylate synthase and p53 for predicting chemoresistance to S-1/cisplatin in gastric cancer

High expression of thymidylate synthase (TS) and inactivation of p53 are allegedly associated with chemoresistance. The authors evaluated TS and p53 expression in gastric cancer treated with neoadjuvant S-1/cisplatin chemotherapy. Paraffin sections of pretreatment biopsy and surgical specimens from 41 gastric cancers were immunostained for TS and p53 protein after appropriate antigen retrieval. Fifty-one cases without neoadjuvant chemotherapy were also studied. In the pretreatment biopsies, high expression of TS was seen in 8% of the histologic responders, in 28% of the nonresponders and in 31% of the controls. High expression of p53 was observed in 56% of the nonresponders, but in 8% of the responders and in 29% of the controls (P<0.01 and P<0.05, respectively). The TS- and/or p53-high phenotype was seen in 76% of the nonresponders and in 54% of the controls, but in 8% of the responders (P<0.0001 and P<0.005, respectively). The data of the surgical specimens were consistent with those of the pretreatment biopsies. These results suggest that immunostaining for TS and p53 protein is useful for pretreatment selection of gastric cancer patients unresponsive to S-1/cisplatin chemotherapy.

Cotransduction of CCL27 gene can improve the efficacy and safety of IL-12 gene therapy for cancer

Interleukin-12 (IL-12) is a potent antitumoral cytokine, but high doses are toxic. Herein, we demonstrate that combinational transduction of IL-12 and CC-chemokine ligand-27 (CCL27) genes into pre-existing murine OV-HM ovarian carcinoma and Meth-A fibrosarcoma, by using RGD fiber-mutant adenoviral vectors, could induce tumor regression and relieve systemic side effects more effectively than either treatment alone. The antitumor activity of the IL-12 and CCL27 combination treatment was T-cell-dependent, and development of long-term specific immunity was confirmed in rechallenge experiments. Immunohistochemical analysis of tumors transduced with CCL27 gene alone or cotransduced with IL-12 and CCL27 genes showed significant increases in numbers of infiltrating CD3(+) T cells, which included both CD4(+) and CD8(+) cells. Additionally, cotransduction with IL-12 and CCL27 genes could more efficiently activate tumor-infiltrating immune cells than transduction with CCL27 alone, as determined by the frequency of perforin-positive cells and expression levels of IFN-gamma. Furthermore, mice treated with the IL-12 and CCL27 combination compared with those treated with IL-12 alone showed milder pathological changes, for example, lymphocyte infiltration and extramedullary hematopoiesis, in lung, liver and spleen. Our data provide evidence that combinational in vivo transduction with IL-12 and CCL27 genes is a promising approach for the development of cancer immunogene therapy that can simultaneously recruit and activate tumor-infiltrating immune cells.

The cationic cell-wall-peroxidase having oxidation ability for polymeric substrate participates in the late stage of lignification of Populus alba L

Previously we reported that purified Cell Wall Peroxidase-Cationic (CWPO-C) from poplar callus (Populus alba L.) oxidizes sinapyl alcohol and polymeric substrate unlike other plant peroxidases and proposed that this isoenzyme is a conceivable lignification specific peroxidase. In this study, we cloned full-length cDNA of CWPO-C and investigated the transcription of CWPO-C gene in various organs and the localization of CWPO-C protein in the differentiating xylem of poplar stem.Real-time PCR analyses indicated that CWPO-C gene is constitutively expressed in the developing xylem, leaf, and shoot but not affected by many stress treatments. Immunohistochemical analysis showed that CWPO-C locates in the middle lamellae, cell corners, and secondary cell walls of the fiber cells during the lignification. The intensity of the CWPO-C labeling increased gradually from the cell wall thickening stage to mature stage of fiber cells, which is very consistent with the increase of lignin content in the developing xylem. These results strongly support that CWPO-C is responsible for the lignification of the secondary xylem. Interestingly, immuno-labeling of CWPO-C was also observed inside of the ray parenchyma cells instead no signals were detected within the developing fiber cells. This suggests that CWPO-C is biosynthesized in the parenchyma cells and provided to the middle lamellae, the cell corners, and the cell walls to achieve lignin polymerization.

Optimization of anti-tumor necrosis factor-alpha single chain Fv displayed on phages for creation of functional antibodies

In this study, we converted the immunoglobulin-type anti-human tumor necrosis factor-alpha (TNF-alpha) monoclonal antibody (Mab) to a scFv-type antibody in order to assess its basic properties. The immunoglobulin VH and VL genes were isolated from the hybridoma that produced an anti-TNF-alpha neutralizing Mab, and they were then linked together to create scFvs of the VL-VH or VH-VL-form. The binding affinity to TNF-a was retained in both scFvs. Interestingly, the VL-VH-type scFv effectively inhibited the TNF-alpha-mediated cytotoxicity, while this neutralization activity was dramatically decreased in the VH-VL-type scFv. These results suggest that the VL-VH-type scFv is a suitable template to create improved versions of the anti-TNF-alpha antibody using a phage display system, and they also show that the structural format must be taken into account in manufacturing scFvs.

Phenotypic and genetic analyses of T-cell-mediated immunoregulation in patients with Type 1 diabetes

AIMS

To investigate the contribution of regulatory T cells and co-stimulatory molecules in CD4(+) T cells to the development of Type 1 diabetes (T1D).

METHODS

Twelve patients with T1D, nine patients with systemic lupus erythematosus (SLE), and 12 age-matched healthy control subjects participated. We analysed the proportions of CD25(+)CD4(+) T cells and natural killer T cells (NKT cells), and the expression levels of Foxp3, CTLA-4, CD28, ICOS, PD-1 and BTLA in peripheral blood mononuclear cells and purified CD4(+) T cells.

RESULTS

There were no significant differences in the proportions of CD25(+) CD4(+) T cells or NKT cells among the three groups. PD-1 expression levels of peripheral CD4(+) T cells from T1D patients were significantly lower than those from healthy control subjects (P = 0.00066). In contrast, PD-1 expression levels were similar in SLE patients and healthy control subjects. The expression levels of Foxp3, CTLA-4, CD28, ICOS and BTLA were similar in the three groups.

CONCLUSIONS

Decreased expression of the PD-1 gene in CD4(+) T cells may contribute to the development and/or maintenance of autoimmune T1D. As the population studied was small and heterogeneous, further studies are required to confirm the findings.

Effectiveness of autologous fibrin tissue adhesive in reducing postoperative blood loss during total hip arthroplasty: a prospective randomised study of 100 cases

PURPOSE

To evaluate the effectiveness of autologous fibrin tissue adhesive (auto-FTA) in reducing blood loss during cementless total hip arthroplasty (THA).

METHODS

From September 2000 to August 2001, 100 patients who predonated 400 ml of autologous blood were randomised to undergo either standard treatment with auto-FTA (auto-FTA group) or standard treatment alone (control group). The volume of postoperative blood loss and the decrease in haemoglobin level were measured. All patients were followed up for 3 years to evaluate the rate of bone ingrowth and heterotopic ossification.

RESULTS

The mean postoperative blood loss was 580 ml (standard deviation [SD], 240 ml) in the auto-FTA group and 810 ml (SD, 341 ml) in the control group; the difference was significant (230 ml, p<0.001). The decrease in haemoglobin concentration was 17 g/l (SD, 11 g/l) in the auto-FTA group and 22 g/l (SD, 12 g/l) in the control group. The difference was significant (5 g/l, p=0.03). The percentage of total blood loss of >1200 ml in any single patient was significantly lower in the auto-FTA group (4%) than in the control group (20%) [p=0.01].

CONCLUSION

Auto-FTA is a safe and effective means of reducing perioperative blood loss in THA.

Isolation and characterization of a novel bacterium, Sphingomonas bisphenolicum strain AO1, that degrades bisphenol A

Bisphenol A (2,2-bis(4-hydroxyphenyl) propane, BPA), which is used as a synthetic resin material or a plasticizer, is a pollutant that possesses endocrine-disrupting activity. Bioremediation of BPA is used to decrease its polluting effects, and here we report a novel bacterial strain AO1, which is able to degrade BPA. This strain was isolated using enrichment cultivation from a soil sample from a vegetable-growing field; the sample was one of 500 soil samples collected across Japan. Strain AO1 degraded 100 mg/l BPA to an undetectable level within 6 h in MYPG medium (containing malt extract, yeast extract, peptone, and glucose) and within 48 h in minimum medium containing 1% glucose at 30 degrees C. Strain AO1 can utilize BPA as a sole source of carbon and as an energy source under aerobic conditions. The estrogenic activity of BPA in MYPG medium was ultimately reduced by strain AO1, although the activity initially increased. Taxonomical analysis showed that strain AO1 is closely related to Sphingomonas chlorophenolicum and S. herbicidovorans, neither of which have a capacity for BPA degradation. DNA-DNA hybridization showed that strain AO1 is a novel species of the Sphingomonas genus, and we designated AO1 as S. bisphenolicum.

Analysis of donor-type chimerism in lineage-specific cell populations after allogeneic myeloablative and nonmyeloablative stem cell transplantation

We analyzed donor-type chimerism in CD3+, CD14.15+ and CD56+ cells from 36 patients who had undergone conventional-intensity allogeneic stem cell transplantation (CST) and 34 patients who had undergone non-myeloablative allogeneic stem cell transplantation (NST) for hematological malignancies. On day 28 after transplantation, all fractions in NST patients and CD3+ cells in CST patients who received a non-total body irradiation (TBI) regimen showed more frequent mixed chimerism (<90% donor cells) than those in patients who had received TBI. NST patients with acute graft-versus-host disease (grade II-IV) frequently showed more than 50% donor-type chimerism in CD3+ cells on day 14 (P=0.029). NST patients with <50% donor-type chimerism on day 14 and with <90% donor-type chimerism on day 28 in CD56+ cells had significantly poor 1-year overall survival (0 vs 91%, P<0.001 and 20 vs 74%, P=0.002, respectively). Both NST and CST patients with <90% donor-type chimerism in CD14.15+ cells on day 28 had significantly poor 1-year overall survival (14 vs 70%, P=0.005 and 0 vs 66%, P=0.002, respectively). Our data show that the extent of donor-type chimerism in lineage-specific cells appears to have an impact on outcome after allogeneic stem cell transplantation.