Epibrassinolide impaired colon tumor progression and induced autophagy in SCID mouse xenograft model via acting on cell cycle progression without affecting endoplasmic reticulum stress observed in vitro

Epibrassinolide is a member of brassinosteroids with a polyhydroxysteroid structure similar to steroid hormones of vertebrates. It was shown that EBR decreased cell proliferation and induced apoptosis in different colon cancer cell lines without exerting a cytotoxic effect in epithelial fetal human colon cells. This finding highlighted the potential of epibrassinolide in clinical therapeutic setup. In our previous studies, we showed that epibrassinolide was able to induce apoptosis via endoplasmic reticulum stress. Recently, we also showed that endoplasmic reticulum and apoptotic stresses can be prevented via autophagic induction in non-cancerous epithelial or aggressive forms of cancer cells. Therefore, here in this study, we evaluated the anti-tumoral effect of epibrassinolide as well as the autophagy involvement in the aggressive forms of colon cancer cell lines as well as in vivo SCID mouse xenograft colon cancer model for the first time. For this purpose, SCID mouse model was used for subcutaneous injection of colon cancer cells in matrigel formulation. We found that autophagy is induced in both in vitro and in vivo models. Following tumor formation, SCID mice were treated daily with increasing concentrations of epibrassinolide for two weeks. Our findings showed that EBR inhibited the volume and diameter of the tumor in a dose-dependent manner by causing cell cycle arrest. Therefore our data suggest that epibrassinolide exerts a cytostatic effect on the agrressive form of colon cancer model in vivo, without affecting endoplasmic reticulum stress and the induction of autophagy might have role in this effect of epibrassinolide.

Comparative characterization of microRNAs of Schistosoma japonicum from SCID mice and BALB/c mice: Clues to the regulation of parasite growth and development

Schistosomiasis, caused by a parasite with a wide range of mammalian hosts, remains one of the most prevailing parasitic diseases in the world. While numerous studies have reported that the growth and reproduction of schistosomes in immunodeficient mice was significantly retarded, the underlying molecular mechanisms have yet to be revealed. In this study, we comparatively analyzed the microRNA expression of Schistosoma japonicum derived from SCID and BALB/c mice on the 35^th day post-infection by high-throughput RNA sequencing as prominent morphological abnormalities had been observed in schistosomes from SCID mice when compared with those from BALB/c mice. The results revealed that more than 72% and 61% of clean reads in the small RNA libraries of female and male schistosomes, respectively, could be mapped to the selected miRs in the miRBase or the sequences of species-specific genomes. Further analysis identified 122 miRNAs using TPM >0.01 as the threshold value, including 75 known and 47 novel miRNAs, 96 of which were commonly expressed across all the four tested schistosome libraries. Comparative analysis of the libraries of schistosomes from SCID and BALB/c mice identified 15 differentially expressed miRNAs (5 up-regulated and 10 down-regulated) among females and 16 among males (9 up-regulated and 7 down-regulated). Integrated analysis of the two sets of differentially expressed miRNAs of female and male worms identified 2 miRNAs (sja-miR-3488 and sja-miR-novel_29) that overlapped between female and male datasets. Prediction of miRNA targets and Gene Ontology (GO) term enrichment analysis of the predicted target genes revealed that these genes were involved in some important biological processes, such as nucleic acid metabolic process, macromolecule modification, and cellular aromatic compound metabolic process. The predicted target genes were further matched to the differentially expressed genes in male and female schistosomes from the above two hosts, obtaining 7 genes that may be responsible for regulating the growth, development and sex maturation of schistosomes. Taken together, this study provides the first identification of differentially expressed miRNAs in schistosomes from SCID and BALB/c mice. These miRNAs and their predicted target mRNAs are probably involved in the regulation of development, growth, and maturation of schistosomes. Therefore, this study expands our understanding of schistosome development regulation and host-parasite relationship, and also provides a valuable set of potential anti-schistosomal targets for prevention and control of schistosomiasis.

Brain damage caused by neonatal hypoxia-ischemia and the effects of hypothermia in severe combined immunodeficient (SCID) mice

Neonatal hypoxic-ischemic encephalopathy (HIE) is a major cause of brain damage in newborns. Although therapeutic hypothermia has been shown to be neuroprotective against neonatal HIE in clinical trials, its effect is not satisfactory. Cell-based therapies have attracted much attention as novel treatments for HIE. Preclinical studies on a variety of human cell transplantation methods have been performed in immunodeficient/immunosuppressed animals, such as severe combined immunodeficient (SCID) mice, which lack functional T and B lymphocytes. The detailed characteristics of neonatal HIE in SCID mice, however, have not been delineated. In preclinical studies, novel therapies for neonatal HIE should be evaluated in combination with hypothermia, which has become a standard treatment for neonatal HIE. However, the effects of hypothermia in SCID mice have not been delineated. In the present study, we compared neonatal hypoxic-ischemic (HI) brain damage in SCID mice and wild-type mice treated with or without hypothermia. Male and female mouse pups were subjected to HI insult induced by unilateral common carotid artery ligation combined with systemic hypoxia on postnatal day 12. In the first 4 h after HI insult, body temperature was maintained at 36 °C for the normothermia groups or 32 °C for the hypothermia groups. The severity of brain damage in SCID mice did not differ from that in wild-type mice based on most evaluations, i.e., cerebral blood flow, hemiparesis, muscle strength, spontaneous activity, cerebral hemispheric volume, neuropathological injury, and serum cytokine levels, although spleen weight, brain weight, leukocyte counts and the levels of some cytokines in the peripheral blood were different between genotypes. The effects of hypothermia in SCID mice were comparable to those in wild-type mice based on most evaluations. Taken together, these findings indicate that SCID mice can be used as an appropriate preclinical model for cell therapies for neonatal HIE.

Efficacy of ultraviolet light-emitting diodes (UV-LED) at four different peak wavelengths against Cryptosporidium parvum oocysts by inactivation assay using immunodeficient mice

As an alternative to using ultraviolet (UV) lamps, which are made with mercury that is toxic to the environment and human health, UV light-emitting diodes (UV-LEDs) are expected to be effective for inactivating microorganisms in water. Although UV-LEDs have been reported to be effective against bacteria and viruses, the effectiveness of UV-LEDs against Cryptosporidium parasites has not been fully evaluated. As we report here, we have developed an in vivo quantitative inactivation assay for C. parvum oocysts using immunodeficient mice. Using the assay, we evaluated the effectiveness of treatment by UV lamp (254 nm) at approximately 1000 μJ/cm² (for 3 s at a distance of 95 mm) compared to inactivation by commercially available UV-LEDs (with peak wavelengths of 268, 275, 284, and 289 nm). The shed patterns of oocysts after treatment with 284- and 289-nm wavelength UV-LEDs were significantly delayed compared to that after treatment with a UV lamp. These findings provide the first suggestion that UV-LEDs are effective against these parasites, as assessed using commercially available 350-mA UV-LEDs under conditions of fixed exposure distance and time.

Preclinical Antimalarial Combination Study of M5717, a Plasmodium falciparum Elongation Factor 2 Inhibitor, and Pyronaridine, a Hemozoin Formation Inhibitor

Antimalarial drug resistance in the Plasmodium falciparum parasite poses a constant challenge for drug development. To mitigate this risk, new antimalarial medicines should be developed as fixed-dose combinations. Assessing the pharmacodynamic interactions of potential antimalarial drug combination partners during early phases of development is essential in developing the targeted parasitological and clinical profile of the final drug product. Here, we have studied the combination of M5717, a P. falciparum translation elongation factor 2 inhibitor, and pyronaridine, an inhibitor of hemozoin formation. Our test cascade consisted of in vitro isobolograms as well as in vivo studies in the P. falciparum severe combined immunodeficient (SCID) mouse model. We also analyzed pharmacokinetic and pharmacodynamic parameters, including genomic sequencing of recrudescent parasites. We observed no pharmacokinetic interactions with the combination of M5717 and pyronaridine. M5717 did not negatively impact the rate of kill of the faster-acting pyronaridine, and the latter was able to suppress the selection of M5717-resistant mutants, as well as significantly delay the recrudescence of parasites both with suboptimal and optimal dosing regimens.

Comparative Transcriptome Analyses of Schistosoma japonicum Derived From SCID Mice and BALB/c Mice: Clues to the Abnormality in Parasite Growth and Development

Schistosomiasis, caused by the parasitic flatworms called schistosomes, remains one of the most prevailing parasitic diseases in the world. The prodigious oviposition of female worms after maturity is the main driver of pathology due to infection, yet our understanding about the regulation of development and reproduction of schistosomes is limited. Here, we comparatively profiled the transcriptome of Schistosoma japonicum recovered from SCID and BALB/c mice, which were collected 35 days post-infection, when prominent morphological abnormalities could be observed in schistosomes from SCID mice, by performing RNA-seq analysis. Of the 11,183 identified genes, 62 differentially expressed genes (DEGs) with 39 upregulated and 23 downregulated messenger RNAs (mRNAs) were found in male worms from SCID mice (S_M) vs. male worms from BALB/c mice (B_M), and 240 DEGs with 152 upregulated and 88 downregulated mRNAs were found in female worms from SCID mice (S_F) vs. female worms from BALB/c mice (B_F). We also tested nine DEGs with a relatively higher expression abundance in the gonads of the worms (ovary, vitellaria, or testis), suggesting their potential biological significance in the development and reproduction of the parasites. Gene ontology (GO) enrichment analysis revealed that GO terms such as “microtubule-based process,” “multicellular organismal development,” and “Rho protein signal transduction” were significantly enriched in the DEGs in S_F vs. B_F, whereas GO terms such as “oxidation–reduction process,” “response to stress,” and “response to DNA damage stimulus” were significantly enriched in the DEGs in S_M vs. B_M. These results revealed that the differential expression of some important genes might contribute to the morphological abnormalities of worms in SCID mice. Furthermore, we selected one DEG, the mitochondrial prohibitin complex protein 1 (Phb1), to perform double-stranded RNA (dsRNA)-mediated RNA interference (RNAi) in vivo targeting the worms in BALB/c mice, and we found that it was essential for the growth and reproductive development of both male and female S. japonicum worms. Taken together, these results provided a wealth of information on the differential gene expression profiles of schistosomes from SCID mice when compared with those from BALB/c mice, which were potentially involved in regulating the growth and development of schistosomes. These findings contributed to an understanding of parasite biology and provided a rich resource for the exploitation of antischistosomal intervention targets.

Selectin Binding Sites Are Involved in Cell Adhesive Properties of Head and Neck Squamous Cell Carcinoma

The formation of distant metastases often determines the fate of patients with head and neck squamous cell carcinoma (HNSCC). The expression of cell adhesion molecules (CAMs) and their ligands of the leukocyte adhesion cascade has been associated with metastatic competence in several malignant entities. In this study, human HNSCC cell lines were analyzed in vitro and in a spontaneous metastatic xenograft model. Immunohistochemical analyses of several CAMs were performed on xenograft tumors and tissue microarrays (TMA) from 453 patients with head and neck squamous cell carcinomas with full histo-pathological and clinical follow-up data. UTSCC 24A and 24B cells bind to E-selectin in vitro, show E-selectin dependent binding to human umbilical vein endothelial cells (HUVECs), and express sLeX. All HNSCC cells engrafted into severe combined immunodeficient (SCID) mice, and UTSCC 24A cells formed sporadically spontaneous lung metastases. The expression of CAMs varied between the cell lines, but a correlation between tumor growth and metastatic potential did not exist. None of the CAMS or their ligands could be identified to be of prognostic relevance in the TMA study. The in vitro results indicate that E-selectin and sLeX are involved in the adhesion of HNSCC cells to endothelium. However, specific prognostic markers chosen from the leukocyte adhesion cascade for HNSCC were not identified.

Comparative Metabonomic Investigations of Schistosoma japonicum From SCID Mice and BALB/c Mice: Clues to Developmental Abnormality of Schistosome in the Immunodeficient Host

The growth and development of schistosome has been affected in the immunodeficient hosts. But it remains unresolved about the molecular mechanisms involved in the development and reproduction regulation of schistosomes. This study tested and compared the metabolic profiles of the male and female Schistosoma japonicum worms collected from SCID mice and BALB/c mice at 5 weeks post infection using liquid chromatography tandem mass spectrometry (LC-MS/MS) platform, in which the worms from SCID mice were the investigated organisms and the worms from BALB/c mice were used as the controls. There were 1015 ion features in ESI+ mode and 342 ion features in ESI- mode were identified after filtration by false discovery rate. Distinct metabolic profiles were found to clearly differentiate both male and female worms in SCID mice from those in BALB/c mice using multivariate modeling methods including the Principal Component Analysis (PCA), Partial Least Squares Discriminant Analysis (PLS-DA), and Orthogonal Partial Least Squares Discriminant Analysis (OPLS-DA). There were more differential metabolites in female worms than in male worms between SCID mice and BALB/c mice. And common and uniquely perturbed metabolites and pathways were identified among male and female worms from SCID mice when compared with BALB/c mice. The enriched metabolite sets of the differential metabolites in male worms between SCID mice and BALB/c mice included bile acid biosynthesis, taurine and hypotaurine metabolism, sphingolipid metabolism, retinol metabolism, purine metabolism, etc. And the enriched metabolite sets of differential metabolites in female worms included retinol metabolism, alpha linolenic acid and linoleic acid metabolism, purine metabolism, sphingolipid metabolism, glutamate metabolism, etc. Further detection and comparison in transcript abundance of genes of the perturbed retinol metabolism and its associated meiosis process in worms identified clues suggesting accumulated retinyl ester and perturbed meiotic process. These findings suggested an association between the schistosome with retarded growth and development in SCID mice and their perturbed metabolites and metabolic pathways, and provided a new insight into the growth and development regulation of S. japonicum worms from the metabolic level, which indicated great clues for discovery of drugs or vaccines against the parasites and disease with more researches.

The TLR3 Agonist Poly Inosinic:Cytidylic Acid Significantly Augments the Therapeutic Activity of an Anti-CD7 Immunotoxin for Human T-cell Leukaemia

We have previously shown that antibody-dependent cellular cytotoxicity (ADCC) cooperates with immunotoxin (IT)-mediated killing of human leukaemia cells in an severe combined immunodeficient (SCID) mouse model of human T-cell acute lymphoblastic leukaemia (SCID-HSB-2 mice), but not in an equivalent non-obese diabetic (NOD)/SCID mouse model. In these earlier studies, we reasoned that diminished ADCC due to the functional deficit in natural killer (NK) cell activity in NOD/SCID mice resulted in a failure of effective perforin/granzyme-mediated cytotoxicity necessary for the delivery of the augmentative effect. Poly-inosinic-cytidylic acid [poly (I:C)] is a synthetic dsRNA toll-like receptor 3 (TLR3) agonist that possesses a number of biological properties that includes the in vivo activation of NK cells. We show here that intravenous (i.v.) injection of SCID mice with [poly (I:C)] results in characteristic time-related changes in serum interleukin 2 (IL-2), IL-12, and interferon γ (INFγ) cytokine levels that are consistent with TLR3 driven activation of SCID mouse NK cells. Concomitantly, there are changes in the expression levels of CD2, CD16/32 (FcγRII/RIII), CD161 (NK1.1), and F4/80 in the bulk splenocyte population. These observed changes correlate with an increase in the in vitro lytic capabilities of putative NK cells from within the splenocyte population of [poly (I:C)] treated SCID mice. We demonstrate that the in vivo activation of NK cells with [poly (I:C)] in SCID mice bearing disseminated human T-cell leukaemia xenografts resulted in a significant improvement in the therapeutic activity exerted by an intact murine monoclonal antibody against human CD7. This was also seen for a saporin-based immunotoxin constructed with the same intact antibody (HB2-SAPORIN), but not with an F(ab’)₂ derivative of the same antibody or of an IT constructed with the same F(ab’)₂ HB2 antibody derivative. This study further demonstrates the previously reported reinforcing role of ADCC for the therapeutic activity of IT in an SCID mouse model of human T-ALL and the potential to significantly boost this further with [poly (I:C)]. Our study provides the rationale to justify the exploration of the clinical utility of IT based therapeutics in combination with TLR3 agonists, such as [poly (I:C)], for the treatment of haematological, and possibly other, malignancies.

A severe combined immunodeficiency disease mouse model of human adenocarcinoma with lepidic-predominant growth

Severe combined immunodeficiency disease (SCID) mice with human lepidic adenocarcinoma were established by the intrabronchial implantation of fresh surgically resected specimens. Human pulmonary adenocarcinoma tissue from 16 different cases was transplanted into SCID mice, and SCID mouse tumors were established from four of these cases (25%). Among the four tumors, the tumor cells of two SCID mice showed replacement lepidic growth of mouse alveolar structures accompanied by multiple intrapulmonary lesions. Human lung carcinoma cell lines showing lepidic growth are rare and the xenograft models using the SCID mouse model developed in the current study will be useful for analyzing the growth and/or progression patterns and clinical behavior of lepidic adenocarcinoma, the major histological subtype of human carcinoma of the lung.

Establishment of a mouse-tick infection model for Theileria orientalis and analysis of its transcriptome

Oriental theileriosis caused by Theileria orientalis is an economically significant disease in cattle farming. The lack of laboratory animal models and in vitro culture systems is a major obstacle in the drive to better understand the biology of this parasite. Notably, research on the sporozoite stage of T. orientalis has rarely been undertaken, although such investigations are of paramount importance for vaccine development based on blocking sporozoite invasion of its host animals. In the present study, we established a mouse-tick infection model for propagating T. orientalis in mice and for producing the sporozoite stage in tick salivary glands. Splenectomized severe combined immunodeficient mice transfused with bovine erythrocytes were infected with T. orientalis. The larval ticks of Haemaphysalis longicornis were then fed on the T. orientalis-infected mice. The piroplasm and sporozoite stages were microscopically observed in the mouse blood and nymphal salivary glands, respectively. The transcriptomics data generated from the piroplasm and sporozoite stages revealed a stage-specific expression pattern for the parasite genes. The mouse-tick infection model and the transcriptomics data it has provided will contribute to a better understanding of T. orientalis biology and will also provide much needed information for the design of effective control measures targeting oriental theileriosis.

Distribution of FcRn Across Species and Tissues

The neonatal Fc receptor (FcRn) is a major histocompatibility complex class I type molecule that binds to, transports, and recycles immunoglobulin G (IgG) and albumin, thereby protecting them from lysosomal degradation. Therefore, besides the knowledge of FcRn affinity, FcRn protein expression is critical in understanding the pharmacokinetic behavior of Fc-containing biotherapeutics such as monoclonal antibodies. The goal of this investigation was to achieve for the first time a comparative assessment of FcRn distribution across a variety of tissues and species. FcRn was mapped in about 20 tissues including placenta from human and the most frequently used species in non-clinical safety testing of monoclonal antibodies (mouse, rat, cynomolgus monkey). In addition, the FcRn expression pattern was characterized in two humanized transgenic mouse lines (Tg32 and Tg276) expressing human FcRn under different promoters, and in the severe combined immunodeficient (SCID) mouse. Consecutive sections were stained with specific markers, namely, anti-CD68 for macrophages and anti-von Willebrand Factor for endothelial cells. Overall, the FcRn expression pattern was comparable across species and tissues with consistent expression of FcRn in endothelial cells and interstitial macrophages, Kupffer cells, alveolar macrophages, enterocytes, and choroid plexus epithelium. The human FcRn transgenic mouse Tg276 showed a different and much more widespread staining pattern of FcRn. In addition, immunodeficiency and lack of IgG in SCID mice had no negative effect on FcRn expression compared with wild-type mice.

The SCID Mouse Model for Identifying Virulence Determinants in Coxiella burnetii

Coxiella burnetii is an intracellular, zoonotic pathogen that is the causative agent of Q fever. Infection most frequently occurs after inhalation of contaminated aerosols, which can lead to acute, self-limiting febrile illness or more serve chronic infections such as hepatitis or endocarditis. Macrophages are the principal target cells during infection where C. burnetii resides and replicates within a unique phagolysosome-like compartment, the Coxiella-containing vacuole (CCV). The first virulence determinant described as necessary for infection was full-length lipopolysaccarride (LPS); spontaneous rough mutants (phase II) arise after passage in immuno-incompetent hosts. Phase II C. burnetii are attenuated in immuno-competent animals, but are fully capable of infecting a variety of host cells in vitro. A clonal strain of the Nine Mile isolate (RSA439, clone 4), has a 26 KDa chromosomal deletion that includes LPS biosynthetic genes and is uniquely approved for use in BL2/ABL2 conditions. With the advances of axenic media and genetic tools for C. burnetii research, the characterization of novel virulence determinants is ongoing and almost exclusively performed using this attenuated clone. A major problem with predicting essential virulence loci with RSA439 is that, although some cell-autonomous phenotypes can be assessed in tissue culture, no animal model for assessing pathogenesis has been defined. Here we describe the use of SCID mice for predicting virulence factors of C. burnetii, in either independent or competitive infections. We propose that this model allows for the identification of mutations that are competent for intracellular replication in vitro, but attenuated for growth in vivo and predict essential innate immune responses modulated by the pathogen during infection as a central pathogenic strategy.

Utility of immunodeficient mouse models for characterizing the preclinical pharmacokinetics of immunogenic antibody therapeutics

Prior to clinical studies, the pharmacokinetics (PK) of antibody-based therapeutics are characterized in preclinical species; however, those species can elicit immunogenic responses that can lead to an inaccurate estimation of PK parameters. Immunodeficient (SCID) transgenic hFcRn and C57BL/6 mice were used to characterize the PK of three antibodies that were previously shown to be immunogenic in mice and cynomolgus monkeys. Four mouse strains, Tg32 hFcRn SCID, Tg32 hFcRn, SCID and C57BL/6, were administered adalimumab (Humira®), mAbX and mAbX-YTE at 1 mg/kg, and in SCID strains there was no incidence of immunogenicity. In non-SCID strains, drug-clearing ADAs appeared after 4-7 days, which affected the ability to accurately calculate PK parameters. Single species allometric scaling of PK data for Humira® in SCID and hFcRn SCID mice resulted in improved human PK predictions compared to C57BL/6 mice. Thus, the SCID mouse model was demonstrated to be a useful tool for assessing the preclinical PK of immunogenic therapeutics.

Identification of IgH gene rearrangement and immunophenotype in an animal model of Epstein-Barr virus-associated lymphomas

Epstein-Barr virus (EBV) is a human oncogenic herpesvirus associated with lymphoma and nasopharyngeal carcinoma. Because the susceptible hosts of EB virus are limited to human and cotton-top tamarins (Saguinus oedipus), there have been no appropriate animal models until the lymphoma model induced by EBV in human peripheral blood lymphocyte (hu-PBL)/SCID chimeric mice was reported. However, it is still controversial whether the EBV-associated lymphoma induced in hu-PBL/SCID mice is a monoclonal tumor. In this study, we transplanted normal human peripheral blood lymphocytes (hu-PBL) from six donors infected with EBV into SCID mice to construct hu-PBL/SCID chimeric mice. The induced tumors were found in the mediastinum or abdominal cavity of SCID mice. Microscopic observation exhibited tumor cells that were large and had a plasmablastic, centroblastic or immunoblastic-like appearance. Immunophenotyping assays showed the induced tumors were LCA-positive, CD20/CD79a-positive (markers of B cells), and CD3/CD45RO-negative (markers of T cells). A human-specific Alu sequence could be amplified by Alu-PCR. This confirmed that induced tumors were B-cell lymphomas originating from the transplanted human lymphocytes rather than mouse cells. EBER in situ hybridization detected positive signals in the nuclei of the tumor cells. Expression of EBV-encoded LMP1, EBNA-1, and EBNA-2 in the tumors was significantly positive. PCR-based capillary electrophoresis analysis of IgH gene rearrangement revealed a monoclonal peak and single amplification product in all six cases of induced tumors. This indicated that EBV can induce monoclonal proliferation of human B lymphocytes and promotes the development of lymphoma. J. Med. Virol. 88:1804-1813, 2016. © 2016 Wiley Periodicals, Inc.

Studies of retroviral infection in humanized mice

Many important aspects of human retroviral infections cannot be fully evaluated using only in vitro systems or unmodified animal models. An alternative approach involves the use of humanized mice, which consist of immunodeficient mice that have been transplanted with human cells and/or tissues. Certain humanized mouse models can support robust infection with human retroviruses including different strains of human immunodeficiency virus (HIV) and human T cell leukemia virus (HTLV). These models have provided wide-ranging insights into retroviral biology, including detailed information on primary infection, in vivo replication and pathogenesis, latent/persistent reservoir formation, and novel therapeutic interventions. Here we describe the humanized mouse models that are most commonly utilized to study retroviral infections, and outline some of the important discoveries that these models have produced during several decades of intensive research.

Effect of oxygen tensions on the proliferation and angiogenesis of endometriosis heterograft in severe combined immunodeficiency mice

OBJECTIVE

To investigate the effects of oxygen on the proliferation and angiogenesis of endometriosis in vivo.

DESIGN

Animal studies.

SETTING

Animal research facility.

ANIMAL(S)

Thirty-six female severe combined immunodeficiency (SCID) mice, implanted with eutopic endometrium from seven endometriosis patients.

INTERVENTION(S)

Human eutopic endometrial tissues were randomized to normoxia, hyperoxia, or hypoxia pretreatment and were subcutaneously implanted into estrogen-treated ovariectomized SCID mice.

MAIN OUTCOME MEASURE(S)

The growth and quality of the implants were measured, and the expression of proliferation- and angiogenesis-associated markers (i.e., Ki67, CD31, vascular endothelial growth factor, and hypoxia-inducible factor-1α) were assessed using immunohistochemistry and Western blot analyses.

RESULT(S)

The growth curves of the implants were distinct with different oxygen pretreatments. The growth of the implants of the hypoxia group was significantly increased compared with the normoxia group, but the growth of the implants of the hyperoxia group was significantly decreased compared with the normoxia group. Microscopic examination indicated that lesions with hyperplastic cylindrical glandular epithelium were surrounded by the endometrial stroma in the hypoxia group, but the glandular epithelium was partially depauperate in the hyperoxia group. The expression of Ki67, CD31, vascular endothelial growth factor, and hypoxia-inducible factor-1α in the hypoxia-pretreated implants was significantly higher compared with the hyperoxia or normoxia groups.

CONCLUSION(S)

Oxygen can alter the growth patterns of endometriosis implants in a SCID mouse model. Hypoxia pretreatment promoted the proliferation and angiogenesis of endometriosis, whereas hyperoxia pretreatment exhibited the opposite effect.

Scid mouse model of psoriasis: a unique tool for drug development of autoreactive T-cell and th-17 cell-mediated autoimmune diseases

In both skin and synovial tissues of psoriatic arthritis (PsA) patients, there are prominent lymphocytic infiltrates localized to the dermal papillae in the skin and the sublining layer stroma in the joint. T-cells, with a predominance of CD4+ lymphocytes, are the most significant lymphocytes in the tissues; in contrast, this ratio is reversed in the epidermis, synovial fluid compartment, and at the enthesis, where CD8+ T-cells are more common. This differential tropism of CD8+ T-cell suggests that the CD8+ T-cells may be driving the immune response in the joint and skin. This is supported by an association with MHC class I. The cytokine network in the psoriatic skin and synovium is dominated by monocyte and T-cell-derived cytokines: IL-1β, IL-2, IL-10, IFN-γ, and TNF-α. In PsA synovium, higher levels of IFN-γ, IL-2, and IL-10 have been detected than in psoriatic skin. An analysis of T-cell receptor beta-chain variable (TCRβV) gene repertoires revealed common expansions in both skin and synovial inflammatory sites, suggesting an important role for cognate T-cell responses in the pathogenesis of PsA and that the inciting antigen may be identical or homologous between the afflicted skin and synovium. Traditionally, T-cells have been classified as T helper 1 (Th1) or Th2 cells by production of defining cytokines, IFN-γ and IL-4, respectively. Recently, a new type of T-cell, Th17, has been linked to autoimmune inflammation. T-helper 17 (Th17) cells are a unique effector CD4+ T-cell subset characterized by the production of interleukin (IL)-17. Murine diseases that were previously considered to be pure Th1-mediated responses have been shown to contain mixed populations of Th1 and Th17 cells. Also, in humans, a critical immunoregulatory role of Th-17 cells in infectious and autoimmune diseases has been identified. It has been postulated that IL-17 may be important in psoriasis. Our initial observations demonstrate that IL-17 and its receptor system are important for PsA also. In in vivo and in vitro studies we have demonstrated that IL-17/IL-17R are enriched in skin, synovial tissue, and synovial fluid of psoriatic arthritis patients and Th17 cells are functionally significant in the pathogenesis of psoriasis and psoriatic arthritis. Here we will share our experience of the SCID mouse model of psoriasis in respect to its use in investigating psoriatic diseases and development of immune-based drugs for psoriasis, psoriatic arthritis, and other autoimmune diseases.

Histological and biological assessment of vitrified ovarian follicles from large animals

Mammalian ovaries contain mixed populations of follicles at different developmental stages. A combination of vitrification and growth culture of ovarian follicles could provide the desired number of mature eggs from a preserved small amount of ovarian tissues. Secondary and primordial follicles from porcine and bovine ovaries were vitrified in solutions containing ethylene glycol, dimethyl sulfoxide and different concentrations of sucrose, and assessed via histological examination, viability staining, xenografting to immunodeficient mice, and in vitro culturing. Histological examination revealed the damage to oocytes and the damage to follicle components separately. The effects of sucrose in vitrification solutions on the follicles were different depending on the developmental stage of the follicle, oocyte size, cell type in the follicle, and species. Viability staining with fluorescein diacetate was useful to assess the damage to oocytes in secondary follicles. In the xenografts, vitrified bovine primordial and secondary follicles developed to the antral stage, and vitrified porcine primordial follicles developed to the secondary stage. Furthermore, bovine secondary follicles formed antrum-like structures in culture. These results suggest that histological examination and viability staining are valuable for assessing the direct effects of vitrification and warming conditions on follicles and oocytes, while xenografting and in vitro culturing can be useful for evaluating the developmental ability of vitrified follicles and oocytes.

Hepatocellular carcinoma xenograft supports HCV replication: A mouse model for evaluating antivirals

AIM: To develop a hepatocellular carcinoma (HCC) xenograft model for studying hepatitis C virus (HCV) replication in a mice, and antiviral treatment.

METHODS: We developed a stable S3-green fluorescence protein (GFP) cell line that replicated the GFP-tagged HCV sub-genomic RNA derived from a highly efficient JFH1 virus. S3-GFP replicon cell line was injected subcutaneously into γ-irradiated SCID mice. We showed that the S3-GFP replicon cell line formed human HCC xenografts in SCID mice. Cells were isolated from subcutaneous tumors and then serially passaged multiple times in SCID mice by culturing in growth medium supplemented with G-418. The mouse-adapted S3-GFP replicon cells were implanted subcutaneously and also into the liver of SCID mice via intrasplenic infusion to study the replication of HCV in the HCC xenografts. The tumor model was validated for antiviral testing after intraperitoneal injection of interferon-α (IFN-α).

RESULTS: A highly tumorigenic S3-GFP replicon cell line was developed that formed subcutaneous tumors within 2 wk and diffuse liver metastasis within 4 wk in SCID mice. Replication of HCV in the subcutaneous and liver tumors was confirmed by cell colony assay, detection of the viral RNA by ribonuclease protection assay and real-time quantitative reverse transcription polymerase chain reaction. High-level replication of HCV sub-genomic RNA in the tumor could be visualized by GFP expression using fluorescence microscopy. IFN-α cleared HCV RNA replication in the subcutaneous tumors within 2 wk and 4 wk in the liver tumor model.

CONCLUSION: A non-infectious mouse model allows us to study replication of HCV in subcutaneous and metastatic liver tumors. Clearance of HCV by IFN-α supports use of this model to test other anti-HCV drugs.

Expression of Cell Surface Receptors on Human Glioblastoma Xenograft Model in NOD/SCID Mouse

PURPOSE

To obtain basic data for development of a glioblastoma-specific immunotoxin, the expression of variable cell surface receptors on a human glioblastoma xenograft model was evaluated, using NOD/SCID mice.

MATERIALS AND METHODS

We developed a xenograft model in NOD/SCID mice implanted with a human glioblastoma cell line (U-87MG). Immunohistochemical studies were performed on implanted tumor nodules (n=8) using antibodies against CD71, EGFR, IGF-IRalpha, CXCR4 and IL-4Ralpha.

RESULTS

Expression of IL-4Ralpha, in implanted tumornodules, was the highest of the cell surface receptors evaluated in this study. However, the endothelial cells in, and around, the tumor nodules also revealed immunopositivity against IL-4Ralpha. The immunoreactivity of IL-4Ralpha, and other surface receptors such as CD71, IGF-IRalpha and EGFR, was prominent in tumor nodules associated with tumor necrosis.

CONCLUSION

IL-4Ralpha would be a possible target for the development of glioblastoma-specific immunotoxin, although there are limitations due to its endothelial expression.