An L314Q mutation in Map3k1 gene results in failure of eyelid fusion in the N-ethyl-N-nitrosourea-induced mutant line.

In this study, we describe an N-ethyl-N-nitrosourea-induced mouse model with a corneal opacity phenotype that was associated with "eye open at birth" (EOB). Histological and immunohistochemistry staining analysis showed abnormal differentiation of the corneal epithelial cells in the mutant mice. The EOB phenotype was dominantly inherited on a C57BL/6 (B6) background. This allele carries a T941A substitution in exon 4 that leads to an L314Q amino acid change in the open reading frame of MAP3K1 (MEEK1). We named this novel Map3k1 allele Map3k1L314Q. Phalloidin staining of F-actin was reduced in the mutant epithelial leading edge cells, which is indicative of abnormality in epithelial cell migration. Interestingly enough, not only p-c-Jun and p-JNK but also c-Jun levels were decreased in the mutant epithelial leading edge cells. This study identifies a novel mouse Map3k1 allele causing EOB phenotype and the EOB phenotype in Map3k1L314Q mouse may be associated with the reduced level of p-JNK and c-Jun.

A C1976Y missense mutation in the mouse Ip3r1 gene leads to short-term mydriasis and unfolded protein response in the iris constrictor muscles.

Ip3r1 encodes an inositol 1,4,5-trisphosphate-responsive calcium channel. Mutations in the IP3R1 gene in humans may cause Gillespie syndrome (GS) typically presents as fixed dilated pupils in affected infants, which was referred to as iris hypoplasia. However, there is no report of mice with Ip3r1 heterozygous mutations showing dilated pupils. Here, we report a new Ip3r1 allele with short-term dilated pupil phenotype derived from an N-ethyl-N-nitrosourea (ENU) mutagenesis screen. This allele carries a G5927A transition mutation in Ip3r1 gene (NM_010585), which is predicted to result in a C1976Y amino acid change in the open reading frame of IP3R1 (NP_034715). We named this novel Ip3r1 allele Ip3r1C1976Y. Histology and pharmacological tests show that the dilated pupil phenotype is a mydriasis caused by the functional defect in the iris constrictor muscles in Ip3r1C1976Y. The dilated pupil phenotype in Ip3r1C1976Y was referred to as mydriasis and excluding iris hypoplasia. IHC analysis revealed increased expression of BIP protein, the master regulator of unfolded protein response (UPR) signaling, in Ip3r1C1976Y mice that did not recover. This study is the first report of an Ip3r1 mutation being associated with the mydriasis phenotype. Ip3r1C1976Y mice represent a self-healing model that may be used to study the therapeutic approach for Ip3r1-related diseases.

Hirschsprung disease is associated with an L286P mutation in the fifth transmembrane domain of the endothelin-B receptor in the N-ethyl-N-nitrosourea-induced mutant line.

Hirschsprung disease (HSCR), or colonic aganglionosis, is a congenital disorder characterized by the absence of intramural ganglia along variable lengths of the colon, resulting in intestinal obstruction. It is the most common cause of congenital intestinal obstruction, with an incidence of 1 in 5,000 live births. N-ethyl-N-nitrosourea (ENU)-induced mutagenesis is a powerful tool for the study of gene function and the generation of human disease models. In the current study, a novel mutant mouse with aganglionic megacolon and coat color spotting was generated by ENU-induced mutagenesis. Histological and acetylcholinesterase (AChE) whole-mount staining analysis showed a lack of ganglion cells in the colon in mutant mice. The mutation was mapped to chromosome 14 between markers rs30928624 and D14Mit205 (Chr 14 positions 103723921 bp and 105054651 bp). The Ednrb (Chr 14 position 103814625-103844173 bp) was identified as a potential candidate gene in this location. Mutation analysis revealed a T>C missense mutation at nucleotide 857 of the cDNA encoding endothelin receptor B (EDNRB) in which a proline was substituted for the highly conserved Lys-286 residue (L286P) in the fifth transmembrane (TM V) domain of this G protein-coupled receptor. The mutant mouse was named Ednrb(m1yzcm) (Ednrb; mutation 1, Yangzhou University Comparative Medicine Center). The results of the present study implicate the structural importance of the TM V domain in Ednrb function, and the Ednrb(m1yzcm) mouse represents a valuable model for the study of HSCR in humans.

Inactivated Sendai virus suppresses murine melanoma growth by inducing host immune responses and down-regulating ß-catenin expression.

OBJECTIVE: This paper aims to investigate the anti-tumor mechanism of inactivated Sendai virus (Hemagglutinating virus of Japan envelope, HVJ-E) for murine melanoma (B16F10). METHODS: The murine dendritic cells (DCs) were treated with HVJ-E, and then the cytokines secreted from DCs and costimulation-related molecules on DCs were measured. Meanwhile, the expression of ß-catenin in HVJ-E treated murine melanoma cells was detected. In addition, HVJ-E was intratumorally injected into the melanoma on C57BL/6 mice, and the immune cells, CTL response and tumor volume were analyzed. RESULTS: HVJ-E injected into B16F10 melanoma obviously inhibited the growth of the tumor and prolonged the survival time of the tumor-bearing mice. Profiles of cytokines secreted by dendritic cells (DCs) after HVJ-E stimulation showed that the number of cytokines released was significantly higher than that elicited by PBS (1P<0.05). The co-stimulation-related molecules on DCs were comparable to those stimulated by LPS. Immunohistochemical examinations demonstrated the repression of ß-catenin in B16F10 melanoma cells after HVJ-E treatment. Meanwhile, real-time reverse transcription PCR revealed that HVJ-E induced a remarkable infiltration of CD11c positive cells, chemokine ligand 10 (CXCL10) molecules, interleukin-2 (IL-2) molecule, CD4(+) and CD8(+) T cells into HVJ-E injected tumors. Furthermore, the mRNA expression level of ß-catenin in the HVJ-E injected tumors was also down-regulated. In addition, B16F10-specific CTLs were induced significantly after HVJ-E was injected into the tumor-bearing mice. CONCLUSION: This is the first report to show the effective inhibition of melanoma tumors by HVJ-E alone and the mechanism through which it induces antitumor immune responses and regulates important signal pathways for melanoma invasion. Therefore, HVJ-E shows its prospect as a novel therapeutic for melanoma therapy.

[The effect of HPV16E7 DNA vaccine transdermal delivery with microneedle array].

OBJECTIVE: To study the effects of DNA vaccine transdermal delivery with microneedle array. METHODS: The pcDNA3.1-HPV16E7 recombinant vector acting as gene vaccine was established. The infiltration quantity of pcDNA3.1-HPV16E7 getting across the microchannels generated by microneedle arrays in vitro was observed. 30 BALB/c mice were divided into 3 groups (experimental group, in vain plasmid group, negative control). Each group had 10 mice. Then immunized BALB/c mice with a dose of 200 microg with microneedle array every two weeks. The control groups did the same as that as the study groups. Two weeks after the third immunization, the serum and lymphocytes were separated to detect the functions of humoral immunity with indirect immunofluorescence test, while, the functions of cellular immunity with lymphocyte transformation test was also detected. RESULTS: The DNA vaccine could easily get across the microchannels generated by microneedle arrays in vitro. Moreover, the course was permanent and the whole infiltration quantity was comparatively high, reaching 0.73819 mg/cm2 at the 30th hour. And among immunized BALB/c mouse, DNA vaccine transdermal delivery with microneedle array could induce specific antibodies. Lymphocyte transformation test showed that there was significant difference for the lymphocyte transformation rate between experiment (the average of lymphocyte transformation rate was 47.25%) and control group (the average of lymphocyte transformation rate was 30.00%) (chi2 = 12.903, P < 0.001). Also, the difference was found between in vain plasmid group (the average of lymphocyte transformation rate was 43.00%) and negative control(chi2 = 7.292, P = 0.007). While, no difference was observed in the experimental group and in vain plasmid group (chi2 = 0.817, P = 0.366). CONCLUSION: The DNA vaccine combined administering with microneedle array might get across the microchannels generated by microneedle arrays in vitro and induce humoral and cellular immune response in vivo.

[Construction of HPV type 16 Li antigen expressing tumor model].

Recombinant expression vector was constructed by techniques of gene recombination, and identified by restriction endonuclease and sequence analysis. Then the recombinant was transfected into B16 cell by techniques of gene transfection and expressions were detected by RT-PCR and IFA. After that, transfected cells were inoculated into subcutaneous of mouse and the forming tumor and expression of HPV16L1 protein after tumor was formed was observed. Identification of pcDNA- HPV16L1 by enzyme digestion showed that the length, inserted location and direction of the target gene which was inserted into the recombinant was correct and the expression of L1 in transfected cell was observed by IFA. The inoculated cells could form tumor in vivo obviously and HPV16 L1 protein could express in the cells stably.

Two kinds of ENU-induced scant hair mice and mapping of the mutant genes.

OBJECTIVE: To establish mouse models for human diseases through N-ethyl-N-nitrosourea (ENU) mutagenesis, and to provide groundwork to clone genes and study their functions after mapping the mutant genes. METHODS: 18 male D2 mice (G0) at age of 8-10 weeks old were injected intraperitoneally with ENU (100 mg/kg) once a week for three consecutive weeks. The treated male mice were mated with females of the same strain, and their offspring (G1) were used to screen for dominant and recessive mutation. After breeding the mutant F2 (D2B6 F1 intercrossing) mice, 39 microsatellites that are equally distributed on the mouse genome and are different between B6 and D2 strains were used to scan the genome. According to the log odds score (LODS) we determined whether these microsatellites were linked to the mutant genes and calculated the location of mutant genes based on their recombination ratio. RESULTS: We screened 532 G1 mice, of which 14 exhibited mutation phenotypes. None was dominantly hereditable. Two cases of recessive inheritable scant hair mice were obtained through testing 30 G1 mice with normal phenotype and potential recessive mutant genes. All showed scant coat hair, grew slowly, and hyperkeratoses of epidermis and bollicular horn plug in histological sections. Their visceral organs were not markedly different from normal, and they were named scant hair 1 Baojin (symbol is snthr(-1Bao)) and scant hair 2 Baojin (symbol is snthr(-2Bao)). Through microsatellite screening we found that the LODS between snthr(-1Bao) and D9Mit243 was 7.73, and the linkage was determined. After analyzing the recombination ratio between snthr(-1Bao) and microsatellite D9Mit18 which was near snthr(-1Bao) based on a total number of 126 F2 mice with the scant hair phenotype, we determined that snthr(-1Bao) was located at chromosome 9 and was 71cM from centromere. Using the same technique, snthr(-2Bao) was mapped to the same position as snthr(-1Bao). CONCLUSION: In our research, two cases of scant hair mice provide good models for the study of dermatology, and the location of mutant genes provides a solid foundation for cloning new mice scant hair genes.