Mesenchymal properties of iPSC-derived neural progenitors that generate undesired grafts after transplantation

Although neural stem/progenitor cells derived from human induced pluripotent stem cells (hiPSC-NS/PCs) are expected to be a cell source for cell-based therapy, tumorigenesis of hiPSC-NS/PCs is a potential problem for clinical applications. Therefore, to understand the mechanisms of tumorigenicity in NS/PCs, we clarified the cell populations of NS/PCs. We established single cell-derived NS/PC clones (scNS/PCs) from hiPSC-NS/PCs that generated undesired grafts. Additionally, we performed bioassays on scNS/PCs, which classified cell types within parental hiPSC-NS/PCs. Interestingly, we found unique subsets of scNS/PCs, which exhibited the transcriptome signature of mesenchymal lineages. Furthermore, these scNS/PCs expressed both neural (PSA-NCAM) and mesenchymal (CD73 and CD105) markers, and had an osteogenic differentiation capacity. Notably, eliminating CD73⁺ CD105⁺ cells from among parental hiPSC-NS/PCs ensured the quality of hiPSC-NS/PCs. Taken together, the existence of unexpected cell populations among NS/PCs may explain their tumorigenicity leading to potential safety issues of hiPSC-NS/PCs for future regenerative medicine.

A robust culture system to generate neural progenitors with gliogenic competence from clinically relevant induced pluripotent stem cells for treatment of spinal cord injury

Cell-based therapy targeting spinal cord injury (SCI) is an attractive approach to promote functional recovery by replacing damaged tissue. We and other groups have reported the effectiveness of transplanting neural stem/progenitor cells (NS/PCs) derived from human induced pluripotent stem cells (hiPSCs) in SCI animal models for neuronal replacement. Glial replacement is an additional approach for tissue repair; however, the lack of robust procedures to drive iPSCs into NS/PCs which can produce glial cells has hindered the development of glial cell transplantation for the restoration of neuronal functions after SCI. Here, we established a method to generate NS/PCs with gliogenic competence (gNS/PCs) optimized for clinical relevance and utilized them as a source of therapeutic NS/PCs for SCI. We could successfully generate gNS/PCs from clinically relevant hiPSCs, which efficiently produced astrocytes and oligodendrocytes in vitro. We also performed comparison between gNS/PCs and neurogenic NS/PCs based on single cell RNA-seq analysis and found that gNS/PCs were distinguished by expression of several transcription factors including HEY2 and NFIB. After gNS/PC transplantation, the graft did not exhibit tumor-like tissue formation, indicating the safety of them as a source of cell therapy. Importantly, the gNS/PCs triggered functional recovery in an SCI animal model, with remyelination of demyelinated axons and improved motor function. Given the inherent safety of gNS/PCs and favorable outcomes observed after their transplantation, cell-based medicine using the gNS/PCs-induction procedure described here together with clinically relevant iPSCs is realistic and would be beneficial for SCI patients.

Concise Review: Laying the Groundwork for a First-In-Human Study of an Induced Pluripotent Stem Cell-Based Intervention for Spinal Cord Injury

There have been numerous attempts to develop stem cell transplantation approaches to promote the regeneration of spinal cord injury (SCI). Our multicenter team is currently planning to launch a first-in-human clinical study of an induced pluripotent stem cell (iPSC)-based cell transplant intervention for subacute SCI. This trial was conducted as class I regenerative medicine protocol as provided for under Japan's Act on the Safety of Regenerative Medicine, using neural stem/progenitor cells derived from a clinical-grade, integration-free human "iPSC stock" generated by the Kyoto University Center for iPS Cell Research and Application. In the present article, we describe how we are preparing to initiate this clinical study, including addressing the issues of safety and tumorigenesis as well as practical problems that must be overcome to enable the development of therapeutic interventions for patients with chronic SCI. Stem Cells 2019;37:6-13.

Modeling neurological diseases with induced pluripotent cells reprogrammed from immortalized lymphoblastoid cell lines

Patient-specific induced pluripotent stem cells (iPSCs) facilitate understanding of the etiology of diseases, discovery of new drugs and development of novel therapeutic interventions. A frequently used starting source of cells for generating iPSCs has been dermal fibroblasts (DFs) isolated from skin biopsies. However, there are also numerous repositories containing lymphoblastoid B-cell lines (LCLs) generated from a variety of patients. To date, this rich bioresource of LCLs has been underused for generating iPSCs, and its use would greatly expand the range of targeted diseases that could be studied by using patient-specific iPSCs. However, it remains unclear whether patient’s LCL-derived iPSCs (LiPSCs) can function as a disease model. Therefore, we generated Parkinson’s disease patient-specific LiPSCs and evaluated their utility as tools for modeling neurological diseases. We established iPSCs from two LCL clones, which were derived from a healthy donor and a patient carrying PARK2 mutations, by using existing non-integrating episomal protocols. Whole genome sequencing (WGS) and comparative genomic hybridization (CGH) analyses showed that the appearance of somatic variations in the genomes of the iPSCs did not vary substantially according to the original cell types (LCLs, T-cells and fibroblasts). Furthermore, LiPSCs could be differentiated into functional neurons by using the direct neurosphere conversion method (dNS method), and they showed several Parkinson’s disease phenotypes that were similar to those of DF-iPSCs. These data indicate that the global LCL repositories can be used as a resource for generating iPSCs and disease models. Thus, LCLs are the powerful tools for generating iPSCs and modeling neurological diseases.

Pathological classification of human iPSC-derived neural stem/progenitor cells towards safety assessment of transplantation therapy for CNS diseases

The risk of tumorigenicity is a hurdle for regenerative medicine using induced pluripotent stem cells (iPSCs). Although teratoma formation is readily distinguishable, the malignant transformation of iPSC derivatives has not been clearly defined due to insufficient analysis of histology and phenotype. In the present study, we evaluated the histology of neural stem/progenitor cells (NSPCs) generated from integration-free human peripheral blood mononuclear cell (PBMC)-derived iPSCs (iPSC-NSPCs) following transplantation into central nervous system (CNS) of immunodeficient mice. We found that transplanted iPSC-NSPCs produced differentiation patterns resembling those in embryonic CNS development, and that the microenvironment of the final site of migration affected their maturational stage. Genomic instability of iPSCs correlated with increased proliferation of transplants, although no carcinogenesis was evident. The histological classifications presented here may provide cues for addressing potential safety issues confronting regenerative medicine involving iPSCs.

Safe and efficient method for cryopreservation of human induced pluripotent stem cell-derived neural stem and progenitor cells by a programmed freezer with a magnetic field

Stem cells represent a potential cellular resource in the development of regenerative medicine approaches to the treatment of pathologies in which specific cells are degenerated or damaged by genetic abnormality, disease, or injury. Securing sufficient supplies of cells suited to the demands of cell transplantation, however, remains challenging, and the establishment of safe and efficient cell banking procedures is an important goal. Cryopreservation allows the storage of stem cells for prolonged time periods while maintaining them in adequate condition for use in clinical settings. Conventional cryopreservation systems include slow-freezing and vitrification both have advantages and disadvantages in terms of cell viability and/or scalability. In the present study, we developed an advanced slow-freezing technique using a programmed freezer with a magnetic field called Cells Alive System (CAS) and examined its effectiveness on human induced pluripotent stem cell-derived neural stem/progenitor cells (hiPSC-NS/PCs). This system significantly increased cell viability after thawing and had less impact on cellular proliferation and differentiation. We further found that frozen-thawed hiPSC-NS/PCs were comparable with non-frozen ones at the transcriptome level. Given these findings, we suggest that the CAS is useful for hiPSC-NS/PCs banking for clinical uses involving neural disorders and may open new avenues for future regenerative medicine.

Grafted Human iPS Cell-Derived Oligodendrocyte Precursor Cells Contribute to Robust Remyelination of Demyelinated Axons after Spinal Cord Injury

Murine- and human-induced pluripotent stem cell-derived neural stem/progenitor cells (iPSC-NS/PCs) promote functional recovery following transplantation into the injured spinal cord in rodents and primates. Although remyelination of spared demyelinated axons is a critical mechanism in the regeneration of the injured spinal cord, human iPSC-NS/PCs predominantly differentiate into neurons both in vitro and in vivo. We therefore took advantage of our recently developed protocol to obtain human-induced pluripotent stem cell-derived oligodendrocyte precursor cell-enriched neural stem/progenitor cells and report the benefits of transplanting these cells in a spinal cord injury (SCI) model. We describe how this approach contributes to the robust remyelination of demyelinated axons and facilitates functional recovery after SCI.

Different combinations of Notch ligands and receptors regulate V2 interneuron progenitor proliferation and V2a/V2b cell fate determination

The broad diversity of neurons is vital to neuronal functions. During vertebrate development, the spinal cord is a site of sensory and motor tasks coordinated by interneurons and the ongoing neurogenesis. In the spinal cord, V2-interneuron (V2-IN) progenitors (p2) develop into excitatory V2a-INs and inhibitory V2b-INs. The balance of these two types of interneurons requires precise control in the number and timing of their production. Here, using zebrafish embryos with altered Notch signaling, we show that different combinations of Notch ligands and receptors regulate two functions: the maintenance of p2 progenitor cells and the V2a/V2b cell fate decision in V2-IN development. Two ligands, DeltaA and DeltaD, and three receptors, Notch1a, Notch1b, and Notch3 redundantly contribute to p2 progenitor maintenance. On the other hand, DeltaA, DeltaC, and Notch1a mainly contribute to the V2a/V2b cell fate determination. A ubiquitin ligase Mib, which activates Notch ligands, acts in both functions through its activation of DeltaA, DeltaC, and DeltaD. Moreover, p2 progenitor maintenance and V2a/V2b fate determination are not distinct temporal processes, but occur within the same time frame during development. In conclusion, V2-IN cell progenitor proliferation and V2a/V2b cell fate determination involve signaling through different sets of Notch ligand-receptor combinations that occur concurrently during development in zebrafish.

Mib-Jag1-Notch signalling regulates patterning and structural roles of the notochord by controlling cell-fate decisions

In the developing embryo, cell-cell signalling is necessary for tissue patterning and structural organization. During midline development, the notochord plays roles in the patterning of its surrounding tissues while forming the axial structure; however, how these patterning and structural roles are coordinated remains elusive. Here, we identify a mechanism by which Notch signalling regulates the patterning activities and structural integrity of the notochord. We found that Mind bomb (Mib) ubiquitylates Jagged 1 (Jag1) and is essential in the signal-emitting cells for Jag1 to activate Notch signalling. In zebrafish, loss- and gain-of-function analyses showed that Mib-Jag1-Notch signalling favours the development of non-vacuolated cells at the expense of vacuolated cells in the notochord. This leads to changes in the peri-notochordal basement membrane formation and patterning surrounding the muscle pioneer cells. These data reveal a previously unrecognized mechanism regulating the patterning and structural roles of the notochord by Mib-Jag1-Notch signalling-mediated cell-fate determination.

Nemo-like kinase suppresses Notch signalling by interfering with formation of the Notch active transcriptional complex

The Notch signalling pathway has a crucial function in determining cell fates in multiple tissues within metazoan organisms. On binding to ligands, the Notch receptor is cleaved proteolytically and releases its intracellular domain (NotchICD). The NotchICD enters the nucleus and acts cooperatively with other factors to stimulate the transcription of target genes. High levels of Notch-mediated transcriptional activation require the formation of a ternary complex consisting of NotchICD, CSL (CBF-1, suppressor of hairless, LAG-1) and a Mastermind family member. However, it is still not clear how the formation of the ternary complex is regulated. Here we show that Nemo-like kinase (NLK) negatively regulates Notch-dependent transcriptional activation by decreasing the formation of this ternary complex. Using a biochemical screen, we identified Notch as a new substrate of NLK. NLK-phosphorylated Notch1ICD is impaired in its ability to form a transcriptionally active ternary complex. Furthermore, knockdown of NLK leads to hyperactivation of Notch signalling and consequently decreases neurogenesis in zebrafish. Our results both define a new function for NLK and reveal a previously unidentified mode of regulation in the Notch signalling pathway.

Chemical peeling with salicylic acid in polyethylene glycol vehicle suppresses skin tumour development in hairless mice

BACKGROUND

Chemical peeling with salicylic acid in polyethylene glycol (PEG) vehicle is used clinically to improve the cosmetic appearance of skin that has been damaged by exposure to the sun. It is well known that cancers of the skin such as basal cell carcinoma and squamous cell carcinoma may be induced by the sun. However, the carcinogenic potential of chemical peeling agents has not been studied.

OBJECTIVES

To evaluate the effects of chemical peeling with 30% salicylic acid in PEG on skin tumour formation in treated vs. control mice.

METHODS

To serve as a model of sun-damaged skin, hairless SKH/hr1 mice were irradiated with ultraviolet (UV) B for 14 weeks, with or without treatment every 2 weeks with 30% salicylic acid in PEG for a total of 18 weeks.

RESULTS

Not only was the total number of tumours greatly reduced in the treated vs. the control mice, but skin tumour development was also slower in the treated vs. the control mice. At the final treatment, the fractions of T and B lymphocytes and natural killer cells from spleens of both groups of mice were comparable, and interferon-gamma production did not differ.

CONCLUSIONS

Our findings suggest that chemical peeling with salicylic acid in PEG may help to prevent as well as to reduce the number of UVB-induced skin tumours.

New formulation of chemical peeling agent: histological evaluation in sun-damaged skin model in hairless mice

BACKGROUND

chemical peelings injure the superficial skin, which is then restored by healing of the wound.

OBJECTIVES

to document the acute and chronic histological changes produced by applying chemical peeling agents used clinically to the UVB-irradiated skin of hairless mice, which served as a model of sun-damaged skin.

DESIGN

three chemical peeling agents, 30% salicylic acid, dissolved in macrogol (a new formulation), 35% trichloroacetic acid (TCA) dissolved in distilled water and 20% glycolic acid dissolved in glycerin were applied to the backs of UVB-irradiated hairless mice. Untreated, irradiated areas of skin served as controls. Specimens were evaluated histologically at 3, 14, 28, and 70 days.

RESULTS

chronic UVB irradiation produced an irregular hypertrophy of the epidermis. The treated areas of irradiated skin recovered by day 70. At 28 days, all skin specimens treated with chemical peeling agents exhibited a unique connective tissue layer composed of fine collagen fibers beneath the epidermis. While 35% TCA produced severe tissue damage marked by inflammation up to day 14, no inflammatory infiltrates were seen with 30% salicylic acid in macrogol at 70 days.

CONCLUSIONS

chemical peeling with 30% salicylic acid dissolved in macrogol led to reorganization of the epidermis and a rebuilding of the superficial dermal connective tissue important in reducing wrinkles, and without evidence of inflammatory infiltrates in an animal model of sun-damaged skin. Findings suggest a possible clinical benefit.

Histologic changes in the skin of hairless mice following peeling with salicylic acid

OBJECTIVE

To clarify the histologic alterations produced by the application of salicylic acid solution, which has been used effectively in chemical peeling without producing a wound or inflammation.

DESIGN

We applied 7.5%, 15.0%, and 30.0% salicylic acid in solutions of ethanol or macrogol to the backs of hairless mice for 20 minutes. The skin was histologically evaluated immediately and at 1, 3, 12, 24, and 48 hours following treatment.

SETTING

The Department of Dermatology, Faculty of Medicine, Kyushu University, Fukuoka, Japan.

MAIN OUTCOME MEASURES

A loss of cornified cells was the only morphologic alteration associated with the treatment, and was followed by the activation of the epidermal basal cells and the underlying fibroblasts.

RESULTS

The 7.5% and 15. 0% salicylic acid solutions produced few histologic changes, whereas the 30.0% salicylic acid in both vehicles macerated and then exfoliated the cornified cells. As the epidermis became thinner, the residual epidermal cells became flattened and were rearranged parallel to the tensile surface load. The cornified material within the hair follicles also became macerated, dilated the follicles, and then dropped off. An apparent increase occurred in the number of cells in the S phase in the epidermal basal cells in 24 hours, leaving the follicular cells unchanged. As the cornified layer thickened in 48 hours, the epidermal cells below it and the underlying fibroblasts resumed their random pretherapy arrangement. Except for the occasional infiltrate of lymphocytes, no degenerative or inflammatory changes occurred. While similar changes occurred with each vehicle, they were relatively faster with the ethanol preparations.

CONCLUSION

The present results suggest that the architecture of the epidermis and the papillary dermis can be regenerated by simply injuring the cornified layer by using topical agents such as salicylic acid that do not cause degeneration or inflammation.

[Monitoring of the cryptococcus count in the cerebrospinal fluid with negative cultures in two cases of serious cryptococcal meningitis]

We monitored the cryptococcus count in the cerebrospinal fluid(CSF) using the filter technique in two cases of serious cryptococcal meningitis during the course of treatment with antifungal agents. Lumbar puncture was performed once a week, and 1 ml of CSF was filtered through a Millipore filter(5.0-micron pore for cells), followed by staining of the filters with Alcian blue. All of the cryptococci on the filter were counted under a light microscope at a magnification of x 100. More than 500/ml and 2,000/ml of cryptococci were still observed in the CFS in Cases 1 and 2, respectively, in whom CFS cultures for Cryptococcus neoformans became negative after 4 weeks of treatment. Even though the treatment with antifungal agents were continued in these cases, cryptococci could still be observed for 5 weeks and 60 weeks on the filter preparations of Cases 1 and 2, respectively, after the CSF cultures became negative. The cryptococcal antigen could also be detected in the CSF during the positive filter preparations in these cases. At autopsy in Case 2, patchy lepromeningeal inflammatory lesions with the characteristic capsules of cryptococci were observed in the subarachnoid space. These observations suggest that cryptococci, which persisted in the CSF despite the negative cultures, were responsible for the lesions in the subarachnoid space and protracted clinical course in the two cases of cryptococcal meningitis.

Response of naevus of Ota to Q-switched ruby laser treatment according to lesion colour

Lesions of naevus of Ota range in colour from light brown to blue, and even greenish-black. To develop guidelines for optimal treatment, we evaluated the number of Q-switched ruby laser treatments required to eliminate the pigmentation of such lesions classified by colour. Over a period of 6 years, we evaluated 151 Japanese patients with naevus of Ota who had been treated with the Q-switched ruby laser at a low energy level (wavelength 694.3 nm; pulse duration 28 x 10-9 s; energy fluence 5 J/cm2; spot size 6.5 mm) every 2 months. Each lesion was classified by colour as brown (n = 22), brown-violet (n = 42), violet-blue (n = 81) and blue-green (n = 6). The 22 predominantly brown lesions attained an excellent (100-95%) or good (95-75%) cosmetic result following three laser treatments in all patients who received this number of treatments. In the 42 brown-violet lesions, 25 of the 29 good or excellent results were achieved after four treatments; the 13 less successful results were in patients who had one to three treatments. In the 81 violet-blue lesions, 54 of the 65 good or excellent results were achieved after four treatments and 64 of 65 after five treatments, whereas all 16 less good results were in patients who had only one to three treatments. However, in the six blue-green lesions, six or more treatments were required to achieve a similarly favourable result. At the end of treatment, the area was virtually free of scarring, and its texture resembled that of the surrounding normal skin. We have confirmed that the use of the Q-switched ruby laser at a low energy level can eliminate the pigmentation of naevus of Ota. While the desired improvement can be obtained within 1 year, the number of treatments appears to depend on the predominant colour of the lesion.

Role of bcl-2 in the development of lymphoid cells from the hematopoietic stem cell

To investigate the role of bcl-2 in lymphohematopoiesis, a long-term bone marrow reconstitution system was established. Transplantation of 1,000 c-Kit+ Sca-1+ and lineage markers negative cells from bcl-2-l-mouse bone marrow resulted in long-term reconstitution of nonlymphoid cells. However, T cells were totally absent and B-lymphocyte development was severely impaired at a very early stage of differentiation in the chimeric mouse. On the other hand, transplantation of day 14 fetal liver cells from bcl-2-l-mice resulted in generation of both T and B cells in the recipient, albeit transiently. These data suggest that bcl-2 plays a critical role in the development of lymphoid progenitor cells from the hematopoietic stem cell (HSC), but is not essential for the development of nonlymphoid cells and the self-renewal of HSC. In addition, lymphopoiesis from fetal liver HSC appears to be less dependent on bcl-2 than adult bone marrow HSC.

A case of connective tissue nevus associated with seborrheic keratosis-like eruption, atrophic scar, alopecia, and microtia

We report a 44-year-old Japanese man who had connective tissue nevus, seborrheic keratosis-like eruptions, atrophic scars on his hands and feet, alopecia, and microtia. These concurrent abnormalities are distinct from previously described multiple malformation syndromes.

Cutaneous sarcoid reactions during long-term remission in a patient with acute myelogenous leukemia

A 68-year-old Japanese man with acute myelogenous leukemia, in long-term remission, developed cutaneous sarcoid reactions on his trunk and extremities. This may suggest that sarcoid-like granulomas be considered as a nonspecific cutaneous sign of underlying leukemia.

Molecular cloning, sequencing, and expression of the genes encoding adenosylcobalamin-dependent diol dehydrase of Klebsiella oxytoca

The pdd genes encoding adenosylcobalamin-dependent diol dehydrase of Klebsiella oxytoca were cloned by using a synthetic oligodeoxyribonucleotide as a hybridization probe followed by measuring the enzyme activity of each clone. Five clones of Escherichia coli exhibited diol dehydrase activity. At least one of them was shown to express diol dehydrase genes under control of their own promoter. Sequence analysis of the DNA fragments found in common in the inserts of these five clones and the flanking regions revealed four open reading frames separated by 10-18 base pairs. The sequential three open reading frames from the second to the fourth (pddA, pddB, and pddC genes) encoded polypeptides of 554, 224, and 173 amino acid residues with predicted molecular weights of 60,348 (alpha), 24,113 (beta), and 19,173 (gamma), respectively. Overexpression of these three genes in E. coli produced more than 50-fold higher level of functional apodiol dehydrase than that in K. oxytoca. The recombinant enzyme was indistinguishable from the wild-type one of K. oxytoca by the criteria of polyacrylamide gel electrophoretic and immunochemical properties. It was thus concluded that these three gene products are the subunits of functional diol dehydrase. Comparisons of the deduced amino acid sequences of the three subunits with other proteins failed to reveal any apparent homology.

[Effects of heat treated cells of intestinal lactic acid bacteria in rats fed a deoxycholic acid diet]

Effects of the administration of heat treated cells of intestinal lactic acid bacteria were examined in rats fed a deoxycholic acid (DCA) diet. Male Wistar rats were given a 0.25% DCA diet with or without the heat treated cells of Enterococcus faecalis AD 1001 (EFH-1) or Lactobacillus reuteri AD 0002 (LRH-2) for 4 weeks. Abnormal increases in serum GOT, GPT, UN and lipoproteins were observed in the rats fed the DCA diet. Furthermore, severe lesions in the kidney as well as in the liver were found in these rats. On the contrary, the increases in serum GOT, UN, VLDL and LDL were significantly suppressed, and markedly fewer lesions in the liver and the kidney were observed in the rats fed the DCA diet plus EFH-1 or LRH-2.

Pityriasis lichenoides-like eruption occurring during therapy for myelogenous leukemia

A 61-year-old Japanese man with chronic myelogenous leukemia developed pityriasis lichenoides-like eruptions during chemotherapy. Histopathological features were also consistent with the disease. The eruption in this case may have been an allergic reaction arising in a depressed immunity induced by chemotherapy.

Local antibody production and immune complex formation in rats experimentally infected with Angiostrongylus cantonensis

The systemic humoral immune responses and tissue localization of worm-antigen, antibodies (IgG), and complement (C3) were examined in rats experimentally infected with Angiostrongylus cantonensis. While the worms remained in the subarachnoid space, it was infiltrated with plasma cells and lymphoid cells containing IgM and IgG. When the infiltration of these cells became more pronounced, the serum antibody titer began to increase. At the same time, deposits of IgM, IgG, and C3 were found in the glomeruli of the kidney. A number of eggs were observed in the lungs, enclosed in granulomatous tissues. Infiltrates of plasma cells including IgM and IgG, and deposits of IgM, IgG, and C3 were detected around the eggs and in the granulomatous tissues. A marked increase in serum antibody was observed. A. cantonensis larvae induce local antibody (IgM and IgG) production in the central nervous system prior to an increase of serum antibody titer. Measurement of cerebrospinal fluid antibody titer at an early stage of infection may confirm infection. The larvae showed no evidence of damage in spite of marked local antibody production in the central nervous system. The eggs in the lungs stimulated both local and systemic antibody production, and immune complexes were formed in the lung and the circulatory system. Immune complexes may participate in the formation of granuloma.

Metastatic adenocarcinoma. A case report demonstrating bullous pemphigoid antigen in the tumor

A case of metastatic adenocarcinoma in the skin of the thigh with an unconfirmed origin is described. Bullous pemphigoid antigen, which is present in the normal basement zone of stratified epithelia, was haphazardly present in the basement membrane zone of the aggregated tumor cells and within the cytoplasm of some cells. This finding indicates that metastatic malignant epithelial cells may produce bullous pemphigoid antigen in the alternative environment, especially if situated in the skin.

Eosinophil chemotactic factor in tumour tissue from a patient with Kimura's disease

An extract of tumour tissue from a patient with Kimura's disease was tested for eosinophil chemotactic activity using the Boyden chamber method. Eosinophil chemotactic activity was detected in the tissue extract, and after gel filtration maximum activity was found in the fraction with a molecular weight of approximately 1000 daltons. This factor may play a role in the tissue eosinophilia which occurs in Kimura's disease.

Neurothekeoma

Neurothekeoma is a rare, benign cutaneous tumor with a fairly distinctive histologic appearance and characteristic clinical features. A second typical case of neurothekeoma in Japan, occurring on the dorsal aspect of the right hand, is presented.

The influence of celomic membranes and a tunnel between celomic cavities on cancer metastasis in poultry

The roles of celomic membranes and celomic structures in preventing cancer metastasis were examined. The relationship between a tunnel in the peritoneal cavity of hens and the cancer metastasis was also investigated. A tunnel between the right and left dorsal hepatic cavities was found in almost half of healthy hens. The tunnel was also found in 17% of hens with cancer. Neoplastic cells were detected in the ascitic fluid of 79% of hens with effusions. Metastasis was most severe in the intestinal peritoneal and left dorsal hepatic cavities, whereas the right dorsal hepatic cavity showed the least involvement. Severe inflammatory responses were found within the metastatic membranes, resulting in an increase in their thickness. In tumor-bearing hens, crevasse-like splits were present within the membranes at the layers of loose connective tissues. It appears that the splits prevent further invasion by the cancer cells. There were no successful lesions on the inner surfaces of air sacs. It is suggested that the tunnel in the peritoneal cavity enhances cancer metastasis. We also conclude that the celomic membranes and their structure in hens retard the spread of cancer by functioning as a barrier against direct spread of the cancer cells.

Immunohistochemical study of lysozyme in lupus miliaris disseminatus faciei

The lysozyme activity in tissue samples from patients with lupus miliaris disseminatus faciei (LMDF), sarcoidosis and foreign body granuloma was investigated using the immunoperoxidase technique. The majority of epithelioid cells and giant cells in LMDF and sarcoidosis showed strong lysozyme staining in their cytoplasm. However, most macrophages and giant cells in foreign body granulomas, including granulomatous reactions to epidermal cysts and other foreign materials, stained weakly for lysozyme or were negative. These results suggest that LMDF is different from the foreign body reaction to inert substances, and may be induced by an immunological mechanism associated with cell-mediated immunity.

Estradiol receptors and ovalbumin in adenocarcinoma of hens

The origin of adenocarcinomas in 10 hens was studied using an assay for estradiol receptors (ERs) and ovalbumin. ERs were found in nine tumors, and ovalbumin was present in eight tumors. Hormonal regulation of this cancer is indicated, and it is suggested that the origin of the tumor is probably the glands of the oviduct.

Teratological studies of hydroxypropylmethylcellulose acetate succinate in rats

A teratogenicity study was carried out in S1c: SD rats orally administered Hydroxypropylmethylcellulose acetate succinate (HPMCAS), a useful pharmaceutical excipient, at dose levels of 625, 1,250 and 2,500 mg/kg/day for a period of 11 days from day 7 to day 17 of gestation. Two-thirds of the pregnant females in each group were sacrificed on Day 21 of gestation and their fetuses were examined. The remaining dams were allowed to litter naturally, and the postnatal development of the offsprings was observed. The incidences of external, internal, and skeletal anomalies were not significantly increased in the fetuses of any treated groups. HPMCAS caused no effects on parturition, lactation, postnatal growth and reproductive ability of the male and female offspring.

Teratological study of hydroxypropylmethylcellulose acetate succinate in rabbits

A teratological study was carried out in New Zealand White rabbits in order to examine the teratogenic potentiality of HPMCAS, a useful pharmaceutical excipient. HPMCAS was orally administered at dose levels of 625, 1,250 and 2,500 mg/kg/day for a period of 13 days from day 6 to day 18 of gestation. All pregnant females were sacrificed on day 29 of gestation and their fetuses were examined. The administration of HPMCAS during a period of organogenesis produced no embryotoxic and teratogenic effects as well as no influence on behavior, appearance and growth of animals.

Studies of hydroxypropylmethylcellulose acetate succinate on fertility in rats

A fertility study was carried out in Slc: SD rats orally administered Hydroxypropylmethylcellulose acetate succinate (HPMCAS), a useful pharmaceutical excipient, at dose levels of 625, 1,250 and 2,500 mg/kg/day. Male rats were treated with HPMCAS from 60 days before pairing until the completion of mating. Female rats received HPMCAS for 22 days, from 14 days prior to mating up to Day 7 of gestation. All pregnant females were sacrificed on Day 21 of gestation and all fetuses were examined for abnormalities. No abnormal signs were seen in mating or fertility in the rat treated with HPMCAS. No external, internal and skeletal anomalies attributable to HPMCAS were observed in the fetuses. It was concluded that HPMCAS had no harmful effect on mating, fertilization, implantation, or embryonic development.

Effects on offspring induced by oral administration of hydroxypropylmethylcellulose acetate succinate to the female rats in peri- and post-natal periods

A perinatal and postnatal study was carried out in Slc: SD rats orally administered Hydroxypropylmethylcellulose acetate succinate (HPMCAS), a useful pharmaceutical excipient, at dose levels of 625, 1,250 and 2,500 mg/kg/day for a period from day 17 of gestation to day 21 after delivery. All pregnant rats were allowed to litter naturally, and the postnatal development of the offsprings was observed. In the administered group of 2500 mg/kg, the liver weight was significantly increased in males and showed a tendency to increase in females as compared with control. No significant differences between the control group and the administered groups were found in postnatal growth and differentiation, behavior and reproductive ability of male and female offsprings.

Pathological observations in experimental candida infection of sensitized guinea pigs

Guinea pigs immunized intramuscularly with heat-killed or viable Candida albicans were infected intracutaneously with C. albicans. Animals with negative delayed hypersensitivity against C. albicans antigen showed similar lesions with non-immunized controls. Delayed hypersensitivity-positive guinea pigs, which were detected in the animals immunized with heat-killed C. albicans in CFA and IFA, demonstrated a delay of the resolution of the inflammatory tissue reaction and, in the animals immunized with C. albicans in CFA, developed a granuloma. These results suggest that both humoral and cell-mediated immunities do not play a significant role for protection against candidiasis and at a late stage of infection, cell-mediated immunity may play a secondary role of the enhancement of resistance to candida infection associated with granuloma formation.

A study on the origin of adenocarcinoma in fowls using immunohistological technique

When tumor tissues collected from 12 hens suffering from so-called adenocarcinoma were stained with antisera by the indirect immunofluorescent method, all of the tissues appeared to contain ovalbumin. We suggest that most adenocarcinomas in the thoracoabdomen of mature hens are oviductal in origin.