First report of large-berry coffee (Coffea liberica) anthracnose caused by Colletotrichum kahawae in China.

Large-berry coffee (Coffea liberica) is one of the three cultivated coffee species and a precious breeding germplasm in China (Yan et al, 2019). Anthracnose is a damaging epidemic disease on coffee worldwide (Mohammed et al. 2015). Between June and September 2022, anthracnose was observed on coffee plants in Puer area, Yunnan, China and disease incidence (% plants diseased) of 8.5%-28.2% was recorded in the field. The disease symptoms were observed at all growth stages. Lesions on leaves were circular or oval, with a white to gray central zone outlined by a brown margin and surrounded by a chlorotic halo, Φ5.1-18.5 mm; some lesions extended and coalesced later to form large, blighted areas, leading to complete leaf senescence, defoliation and bare blighted branches on heavily infected trees. The spots on coffee berries were oval or fusiform, sunken and brown-black; diseased berries became gray-black and dried-out but remained on the tree. Leaves with typical anthracnose lesions were collected from fields in Simao ( 22.07°E,100.98°N) to isolate the pathogen. Leaf pieces (5×5mm) from the lesion margin were cut, surface-sterilized with 75% ethanol and 2% NaClO, and cultured on PDA at 25°C. Three isolates with the same colony morphology were obtained by hyphal tip purification. Detached and intact leaves of 6-month coffee seedlings were inoculated with Φ5mm mycelial discs of the isolates. Anthracnose lesions developed on the inoculated leaves, with all 3 isolates, 7d after incubation in a growth chamber (25°C, > 90% RH and lighting 8 h/d at 11000 lux). Pathogens with the same colony morphology as those of the original isolates were re-isolated from the infected tissues of inoculated leaves, thus fulfilling Koch's Postulates. The ITS sequence (PP550861) for the isolate was PCR-amplified and Blast-n analyses showed 100 % (554/554bp) identity to Colletotrichum kahawae LWTJ01; so they were the same population and coded as KFTJ02. The actin (ACT), calmodulin(CAL), glyceraldehydes-3-phosphate dehydrogenase (GAPHD) and histone 3 (HIS3) genes (Qiu et al. 2020) were amplified from one of KFTJ02 isolates, sequenced and deposited in NCBI GenBank (OR842543, OR842544, OR842545 & OR842546). A phylogenetic tree was generated based on the concatenated sequences of the four genes and those of related Colletotrichum spp. using MEGA 6.0 and KFTJ02 clustered in the same clade with C. kahawae IMI319418 on the tree (Bootstrap sup.=88%). When cultured at 25°C on PDA for 7 days, its colonies were near round or ovoid, gray-white, contoured, Φ73.2-80.1 (76.2±2.3)mm or growth rate 10.2-11.1(8.1) mm/d (n=10). The hyphae were hyaline, septated, branching at near right angles. Conidial masses formed 14 days after incubation. The conidia were elliptical, hyaline, monocellular, 10.2-15.5 (12.7±1.06)×3.8-5.2 (4.3±0.52) µm (n=50). The appressoria were black-brown, oval or irregular, 7.8-9.3 (8.5±0.81)µm (n= 50). These morphological characteristics were consistent with those of C. kahawae (Bridge et al, 2008). Therefore, KFTJ02 was identified as C. kahawae, which has been found to infect Camellia oleifera, Areca catechu and Ficus microcarpa (Wei et al, 2023; Zhang et al, 2020; Lin 2023). The coffee berry disease pathogen (C. kahawae) is a quarantine species which has not been recorded and so it is first reported on coffee crops in China. Results of the present study provide important references for further studies on this disease.

STEAP3 Affects Ovarian Cancer Progression by Regulating Ferroptosis through the p53/SLC7A11 Pathway.

Ovarian cancer (OC) is a common malignant cancer in women with a low overall survival rate, and ferroptosis may be a potential new strategy for treatment. Six-transmembrane epithelial antigen of prostate 3 (STEAP3) is a gene closely related to ferroptosis, yet the role of STEAP3 in OC has not yet been thoroughly investigated. Using biological information analysis, we first found that STEAP3 was highly expressed in OC, which was significantly associated with poor prognosis of patients and was an independent prognostic factor. Through cloning, scratch, and transwell experiments, we subsequently found that knockdown of STEAP3 significantly reduced the proliferation and migration ability of OC cells. Furthermore, we found that knockdown of STEAP3 induced ferroptosis in OC cells by detecting ferroptosis indicators. Mechanistically, we also found that knockdown of STEAP3 induced ferroptosis through the p53/SLC7A11 signaling pathway. Through tumorigenic experiments in nude mice, we finally verified that the knockdown of STEAP3 could inhibit tumor growth in vivo by promoting ferroptosis through the p53 pathway. Overall, our study identified a novel therapeutic target for ferroptosis in OC and explored its specific mechanism of action.

Glucose-regulated protein 94 facilitates the proliferation of the Bombyx mori nucleopolyhedrovirus via inhibiting apoptosis.

Glucose regulatory protein 94 (GRP94) is an endoplasmic reticulum (ER)-resident member of the heat shock protein 90 (HSP90) family, that plays an important role in secreted protein folding. Bombyx mori nuclear polyhedrosis virus (BmNPV) is one of the main pathogens in sericulture, causing serious economic losses every year. Previous studies showed that HSP90 members promote BmNPV replication in silkworm, but the function of BmGRP94 in BmNPV infection and proliferation is still not understood. In this study, we investigated the interplay between BmGRP94 and BmNPV infection in silkworm. We first identified a single gene of BmGRP94 in the Bombyx mori genome, which encodes a polypeptide with 810 amino acids in length. Spatio-temporal expression profiles showed that BmGRP94 was highly expressed in hemocytes and midgut, and was significantly induced by BmNPV infection. Furthermore, overexpression of BmGRP94 facilitates viral proliferation, while BmGRP94 inhibition evidently decreased BmNPV proliferation in BmN cells and in silkworm midgut. Mechanistically, BmGRP94 inhibition triggers ER stress, as judged by increased expression of PERK/ATF4/ERO1, H2O2 production, and ER calcium efflux, which promotes cell apoptosis to restrict BmNPV replication in silkworm. These results suggest that BmGRP94 plays an important role in facilitating BmNPV proliferation, and provides a potential molecular target for BmNPV prevention.

Characterization of a silkworm UFM1 homolog in regulating Bombyx mori unfolded protein response and nucleopolyhedrovirus replication.

The Ubiquitin (Ub)-like molecules is essential for animal development and the physiopathology of multiple tissues in the vertebrate. Ubiquitin-fold modifier 1 (UFM1) is one of the newly-identified UBL, which is covalently attached to its substrates through the orchestrated action of a dedicated enzymatic cascade. Bombyx mori nuclear polyhedrosis virus (BmNPV) is one of the main pathogens in sericulture, causing serious economic losses every year. However, there are no studies on UFMylation and the effect of UFMylation on BmNPV replication in silkworm. In this study, we identified BmUFM1 in the B. mori genome. Spatio-Temporal expression profiles showed that BmUFM1 expression was highly in hemocytes and response to various pathogenic stimuli. Furthermore, BmUFM1 is involved in the regulation of ER stress induced Unfolded Protein Response (UPR) and knockdown of BmUFM1 inhibited BmNPV replication. Overall, these results suggest that BmUFM1 plays an important role in facilitating BmNPV proliferation in silkworm. Our findings advance the understanding of UFM1's conjugation machinery, and also provides a potentially molecular target for BmNPV prevention and silkworm breeding.

Cell-autonomous inflammation of BRCA1-deficient ovarian cancers drives both tumor-intrinsic immunoreactivity and immune resistance via STING.

In this study, we investigate mechanisms leading to inflammation and immunoreactivity in ovarian tumors with homologous recombination deficiency (HRD). BRCA1 loss is found to lead to transcriptional reprogramming in tumor cells and cell-intrinsic inflammation involving type I interferon (IFN) and stimulator of IFN genes (STING). BRCA1-mutated (BRCA1mut) tumors are thus T cell inflamed at baseline. Genetic deletion or methylation of DNA-sensing/IFN genes or CCL5 chemokine is identified as a potential mechanism to attenuate T cell inflammation. Alternatively, in BRCA1mut cancers retaining inflammation, STING upregulates VEGF-A, mediating immune resistance and tumor progression. Tumor-intrinsic STING elimination reduces neoangiogenesis, increases CD8+ T cell infiltration, and reverts therapeutic resistance to dual immune checkpoint blockade (ICB). VEGF-A blockade phenocopies genetic STING loss and synergizes with ICB and/or poly(ADP-ribose) polymerase (PARP) inhibitors to control the outgrowth of Trp53-/-Brca1-/- but not Brca1+/+ ovarian tumors in vivo, offering rational combinatorial therapies for HRD cancers.

Turning Cold into Hot: Firing up the Tumor Microenvironment.

Cancers develop within complex tissue environments consisting of diverse innate and adaptive immune cells, along with stromal cells, vascular networks, and many other cellular and noncellular components. The high heterogeneity within the tumor microenvironment (TME) remains a key obstacle in understanding and treating cancer. Understanding the dynamic functional interplay within this intricate ecosystem will provide important insights into the design of effective combinatorial strategies against cancer. Here, we present recent technical advances to explore the complexity of the TME. Then, we discuss how innate immune sensing machinery, genetic alterations of oncogenic signaling, cellular metabolism, and epigenetic factors are involved in modulating the TME. Finally, we summarize the potential strategies to boost antitumor immunity by therapeutically exploiting the TME.

Brucea javanica oil emulsion injection (BJOEI) as an adjunctive therapy for patients with advanced colorectal carcinoma: A protocol for a systematic review and meta-analysis.

BACKGROUND: Brucea javanica oil emulsion injection (BJOEI) has been widely applied as a promising adjunctive drug for colorectal carcinoma (CRC). However, the exact effects and safety of BJOEI remains controversial. In this study, we aimed to summarize the efficacy and safety of BJOEI for the treatment of advanced CRC through the meta-analysis, in order to provide scientific reference for the design of future clinical trials. METHODS: Eligible prospective controlled clinical trials were searched from PubMed, Cochrane Library, Google Scholar, Medline, Web of Science (WOS), Excerpt Medica Database (Embase), Chinese BioMedical Database (CBM), China Scientific Journal Database (VIP), China National Knowledge Infrastructure (CNKI) and Wanfang Database. Papers in English or Chinese published from January 2000 to May 2020 will be included without any restrictions. The clinical outcomes including therapeutic effects, quality of life (QoL), immune function and adverse events, were systematically evaluated.Study selection and data extraction will be performed independently by 2 reviewers. Review Manager 5.3 and Stata 14.0 were used for data analysis, and a fixed or random-effect model will be used depending upon the heterogeneity observed between trials. Subgroup and meta-regression analysis will be carried out depending on the availability of sufficient data. RESULTS: The results of this systematic review will be published in a peer-reviewed journal. CONCLUSION: Our study will draw an objective conclusion of the effects and safety of BJOEI for advanced CRC, and provide a helpful evidence for clinicians to formulate the best postoperative adjuvant treatment strategy for CRC patients.INPLASY registration number: INPLASY202060014.

The disease stage-associated imbalance of Th1/Th2 and Th17/Treg in uterine cervical cancer patients and their recovery with the reduction of tumor burden.

BACKGROUND: Nearly all uterine cervical cancer (UCC) cases result from human papillomavirus (HPV) infection. After high-risk HPV infection, most HPV infections are naturally cleared by humoral and cell-mediated immune responses. Thus, cervical lesions of only few patients progress into cervical cancer via cervical intraepithelial neoplasia (CIN) and lead to persistent oncogenic HPV infection. This suggests that immunoregulation plays an instrumental role in the carcinogenesis. However, there was a few studies on the relation between the immunologic dissonance and clinical characteristics of UCC patients. METHOD: We examined the related immune cells (Th1, Th2, Th17, and Treg cells) by flow cytometric analysis and analyzed their relations with UCC stages, tumor size, differentiation, histology type, lymph node metastases, and vasoinvasion. Next, we quantified the Th1, Th2, Th17, and Treg cells before and after the operation both in UCC and CIN patients. RESULTS: When compared with stage I patients, decreased levels of circulating Th1 cells and elevated levels of Th2, Th17, and Treg cells were detected in stage II patients. In addition, the imbalance of Th1/Th2 and Th17/Treg cells was related to the tumor size, lymph node metastases, and vasoinvasion. We found that immunological cell levels normalized after the operations. In general, immunological cell levels in CIN patients normalized sooner than in UCC patients. CONCLUSIONS: Our findings suggested that peripheral immunological cell levels reflect the patient's condition.

Evaluation of an Exclusive Spur Dike U-Turn Design with Radar-Collected Data and Simulation.

Traditional U-turn designs can improve operational features obviously, while U-turn diversions and merge segments still cause traffic congestion, conflicts, and delays. An exclusive spur dike U-turn lane design (ESUL) is proposed here to solve the disadvantages of traditional U-turn designs. To evaluate the operation performance of ESUL, a traffic simulation protocol is needed. The whole simulation process includes five steps: data collection, data analysis, simulation model build, simulation calibration, and sensitive analysis. Data collection and simulation model build are two critical steps and are described later in greater detail. Three indexes (travel time, delay, and number of stops) are commonly used in the evaluation, and other parameters can be measured from the simulation according to experimental needs. The results show that the ESUL significantly diminishes the disadvantages of traditional U-turn designs. The simulation can be applied to solve microscopic traffic problems, such as in single or several adjacent intersections or short segments. This method is not suitable for larger scale road networks or evaluations without data collection.

MiR-301a-3p in the pathogenesis of bacterial meningitis by targeting Cx43.

Gap junction (GJ) is concerned with cell growth, differentiation, immune response, as well as many physiological and pathological processes. Cx43, as an important GJ protein, is associated with a variety of diseases. This study investigated the effect of miR-301a-3p in bacterial meningitis by targeting the Cx43 gene. The negative correlation between Cx43 and miR-301a-3p was because of the abnormal expression of related genes. MiR-301a-3p agomir was transfected into astrocytes for higher expression; CCK8 assay and flow cytometry showed that the high expression of miR-301a-3p would inhibit apoptosis and induces proliferation of astrocytes, whereas miR-301a-3p antagomir would inhibit proliferation and induce apoptosis. Bioinformatics analysis showed that Cx43 was the target gene of miR-301a-3p, and dual-luciferase assay and experiments repeated showed that miR-301a-3p regulated the expression of Cx43 on the 3'-untranslated region seed region. Therefore, miR-301a-3p played a biological role in the development of bacterial meningitis by regulating the expression of the target gene Cx43.

Imbalance of Th1/Th2 and Th17/Treg during the development of uterine cervical cancer.

Uterine cervical cancer (UCC) causes more than one quarter of a million deaths per year in many developing countries. Nearly all cases of cervical cancer result from infection with the human papillomavirus. After high-risk HPV infection, most HPV infections are cleared naturally as a result of humoral and cell-mediated immune responses. Only a limited number of patients' cervical lesions progress through CIN to cervical cancer, from persistent oncogenic human papillomavirus (HPV) infection. This indicated that immunoregulation may play a central role in the HPV-induced carcinogenesis. However, the natural history of clearance of a cervical HPV infection or its progression to a UCC needs clarification. We examined the related immune cells (Th1, Th2, Th17 and Treg cells) and related immune factors (INF-γ, IL-4, IL-10, IL-17, IL-23, TGF-ßI) of UCC patients, CIN patients, HPV infected patients, and healthy controls. Compared with healthy controls, patients with UCC or CIN had a lower proportion of Th1 cells, and a higher proportion of Th2, Th17, and Treg cells. IL-4, IL-10, IL-17, IL-23 and TGF-ßI concentrations in serum were found to be increased from patients with UCC or CIN, while INF-γ concentration in serum with UCC or CIN decreased. Our findings suggested that there were attractive imbalances of Th1/Th2 and Th17/Treg cells in UCC and CIN patients. HPV persistent infection induced an immunologic dissonance, and the degree of imbalance is aggravated with the progression of the disease.

miR-1290 Contributes to Colorectal Cancer Cell Proliferation by Targeting INPP4B.

Colorectal cancer (CRC) is one of the most common oncological conditions worldwide, to date. MicroRNA-1290 (miR-1290) has been demonstrated to regulate its progression. We studied the role of miR-1290 in CRC progression. The gene was upregulated in CRC tissues and cells. Its overexpression promoted CRC cell proliferation analyzed by MTT assay, colony formation assay, and soft agar growth assay. In addition, miR-1290 knockdown inhibited CRC cell proliferation. We also found that miR-1290 overexpression reduced the p27 level and increased cyclin D1 at both the mRNA and protein levels, whereas miR-1290 knockdown increased p27 and reduced cyclin D1, confirming miR-1290 promoted CRC cell proliferation. Inositol polyphosphate 4-phosphatase B (INPP4B) was the target of miR-1290. Luciferase reporter assay revealed that miR-1290 directly bound to the 3'-UTR of INPP4B; the mutated seed sites in miR-1290 abrogated this effect. Double knockdown of INPP4B and miR-1290 promoted CRC cell proliferation, suggesting miR-1290 promoted CRC cell proliferation by targeting INPP4B.

[Establishment of Assessment Method for Air Bacteria and Fungi Contamination].

In this paper, in order to settle existing problems in the assessment of air bacteria and fungi contamination, the indoor and outdoor air bacteria and fungi filed concentrations by impact method and settlement method in existing documents were collected and analyzed, then the goodness of chi square was used to test whether these concentration data obeyed normal distribution at the significant level of α = 0.05, and combined with the 3σ principle of normal distribution and the current assessment standards, the suggested concentrations ranges of air microbial concentrations were determined. The research results could provide a reference for developing air bacteria and fungi contamination assessment standards in the future.

[Airborne Fungal Aerosol Concentration and Distribution Characteristics in Air- Conditioned Wards].

The effects of airborne fungus on human health in the hospital environment are related to not only their genera and concentrations, but also their particle sizes and distribution characteristics. Moreover, the mechanisms of aerosols with different particle sizes on human health are different. Fungal samples were obtained in medicine wards of Chongqing using a six-stage sampler. The airborne fungal concentrations, genera and size distributions of all the sampling wards were investigated and identified in detail. Results showed that airborne fungal concentrations were not correlated to the diseases or personnel density, but were related to seasons, temperature, and relative humidity. The size distribution rule had roughly the same for testing wards in winter and summer. The size distributions were not related with diseases and seasons, the percentage of airborne fungal concentrations increased gradually from stage I to stage III, and then decreased dramatically from stage V to stage VI, in general, the size of airborne fungi was a normal distribution. There was no markedly difference for median diameter of airborne fungi which was less 3.19 µm in these wards. There were similar dominant genera in all wards. They were Aspergillus spp, Penicillium spp and Alternaria spp. Therefore, attention should be paid to improve the filtration efficiency of particle size of 1.1-4.7 µm for air conditioning system of wards. It also should be targeted to choose appropriate antibacterial methods and equipment for daily hygiene and air conditioning system operation management.

Documentary Research of Human Respiratory Droplet Characteristics.

Respiratory droplet characteristics are key to determine the droplet-borne pathogen transmission, which provide scientific basis for formulating the disease prevention from droplet transmission and control measures. Through studying the data information from existing documents, this paper gives the respiratory droplet characteristics, like size, concentration, velocity, etc. Meanwhile, droplet evaporation, droplet-borne pathogen activity and their transmission are discussed. The droplet size is no significant difference with human health level, gender and age. The size of droplets produced by health people is between 0.1 and 10 µm, it produced by patients is between 0.05 and 10 µm, and the patients' droplet concentration is higher. The coughed droplet concentrations change with the size into a peak rule. The velocity of the cough droplets is the biggest, the range of 10 to 25m/s, the transmission distance is more than 2m.

[Research on relations among self-esteem, self-harmony and interpersonal-harmony of university students].

OBJECTIVE: To learn characteristics and their mutual relations of self-esteem, self-harmony and interpersonal-harmony of university students, in order to provide the basis for mental health education. METHODS: With a stratified cluster random sampling method, a questionnaire survey was conducted in 820 university students from 16 classes of four universities, chosen from 30 universities in Anhui Province. Meanwhile, Rosenberg Self-esteem Scale, Self-harmony Scale and Interpersonal-harmony Diagnostic Scale were used for assessment. RESULTS: Self-esteem of university students has an average score of (30.71 +/- 4.77), higher than median thoery 25, and there existed statistical significance in the dimensions of gender (P = 0.004), origin (P = 0.038) and only-child (P = 0.005). University students' self-harmony has an average score of (98.66 +/- 8.69), among which there were 112 students in the group of low score, counting for 13.7%, 442 in that of middle score, counting for 53.95%, 265 in that of high score, counting for 32.33%. And there existed no statistical significance in the total-score of self-harmony and score differences from most of subscales in the dimention of gender and origin, but satistical significance did exist in the dimention of only-child (P = 0.004). It was statistically significant (P = 0.006) on the "stereotype" subscales, on the differences between university students from urban areas and rural areas. Every dimension of self-esteem and self -harmony and interpersonal harmony was correlated and statistically significant. Multiple regression analysis found that when there was a variable in self-esteem, the amount of the variable of self-harmony for explaination of interpersonal conversation dropped from 22.6% to 12%, and standard regression coefficient changing from 0.087 to 0.035. The trouble of interpersonal dating fell from 27.6% to 13.1%, the standard regression coefficient changing from 0.104 to 0.019. The bother of treating people fell from 30.9% to 15%, and the standard regression coefficient changing from 0.079 to 0.020. The problem of heterosexual contact fell from 23.4% to 17.3%, and the standard regression coefficient changing from 0.095 to 0.024. CONCLUSION: Self-esteem was a mediator variable between self-harmony and interpersonal-harmony. By cultivating university students' level of self-esteem to achieve their self-harmony and interpersonal-harmony, university students' mental health level can be improved.

Expression and possible role of interleukin-10 receptors in patients with adenomyosis.

OBJECTIVE: To investigate the expression and potential roles of interleukin-10 receptor 1 (IL-10R1) and interleukin-10 receptor 2 (IL-10R2) in adenomyosis. STUDY DESIGN: This prospective study examined 33 women with histologically proven adenomyosis and 21 women without adenomyosis who had undergone hysterectomy for non-endometrial pathology. Comparative immunohistochemistry was used to evaluate the expression and localization of IL-10R1 and IL-10R2. Tissue sections were immunostained with goat anti-human interleukin-10 receptor alpha and rabbit anti-human interleukin-10 receptor beta antibodies. The presence and localization of IL-10R1 and IL-10R2 were evaluated microscopically throughout the menstrual cycle in eutopic and ectopic endometrial tissues of women with adenomyosis, and the results were compared with those for normal endometrium. RESULTS: IL-10R1 and IL-10R2 were mainly expressed by epithelial cells in both women with adenomyosis and controls. Epithelial expression of IL-10R1 and IL-10R2 was higher in adenomyotic samples than in eutopic endometrium of women with adenomyosis or normal endometrium. Moreover, epithelial expression of IL-10R1 was higher in eutopic endometrium of women with adenomyosis than in normal endometrium. Epithelial expression of IL-10R1 showed cyclic variation in eutopic endometrium of women with adenomyosis and normal endometrium, with elevated expression in secretory-phase tissues compared with proliferative-phase tissues. CONCLUSIONS: Intrinsic abnormalities concerning IL-10 and IL-10 receptors may be present in eutopic and ectopic endometria of women with adenomyosis. These findings suggest that IL-10 receptors may be involved in the immunotolerant and/or anti-inflammatory process of adenomyosis.

5-Aza-2'-deoxycytidine is a potent inhibitor of DNA methyltransferase 3B and induces apoptosis in human endometrial cancer cell lines with the up-regulation of hMLH1.

The aim of our study was to evaluate the effects of 5-aza-2'-deoxycytidine (5-azadC) on cell growth inhibition, cell cycle arrest, apoptosis as well as the expression levels of hMLH1 and DNMT3B in human endometrial cancer cell lines. Ishikawa, HHUA, and KLE cell lines were used. After treatment with 5-azadC, cells were measured by MTT to detect the growth inhibition. Flow cytometry analysis was used to evaluate the cell cycle distribution and apoptosis effect. The expression of hMLH1 and DNMT3B was performed by real-time PCR and Western blotting analysis. The methylation status of the hMLH1 gene was monitored by methylation-specific PCR. We confirmed that 5-azadC treatment resulted in growth inhibition, G(2) arrest, and cell apoptosis in human endometrial cancer cell lines. Furthermore, the data obtained by real-time PCR and Western blotting analysis demonstrated that the expression of hMLH1 was up-regulated by 5-azadC treatment in Ishikawa cells, accompanied by down-regulation of DNMT3B expression, when 5-azadC led to cell inhibition, G(2)/M arrest, and apoptosis. Our results suggested that 5-azadC is a potent inhibitor of DNA methyltransferase 3B and induces apoptosis in Ishikawa cells with the up-regulation of hMLH1.

Optimization of multidrug resistance 1 gene transfer confers chemoprotection to human hematopoietic cells engrafted in immunodeficient mice.

OBJECTIVE: To investigate whether an optimization of MDR1 gene transfer protocol would result in stable hematopoietic stem cell (HSC) engraftment and myeloprotection in non-obese diabetic/severe combined immunodeficient (NOD/SCID) mice after paclitaxel chemotherapy. METHODS: We transplanted freshly isolated CD34+ cells or MDR1-transduced CD34+ cells derived from human umbilical cord blood (UCB) into sublethally irradiated NOD/SCID mice. Twenty-eight days after transplantation, mice received paclitaxel chemotherapy and peripheral blood (PB) was collected for analysis of WBC, RBC and PLT counts once every week. RESULTS: We found that MDR1-transduced human hematopoietic cells could facilitate hematopoietic recovery and completely reconstitute hematopoiesis in mice as well as freshly isolated CD34+ cells. Mice transplanted with MDR1-transduced human hematopoietic cells were protected from paclitaxel chemotherapy with higher survival rate and higher level of WBC counts and RBC counts compared with mice transplanted with untransduced HSCs. We also demonstrated that hematopoietic cells transduced with MDR1 gene were enriched in vivo after paclitaxel chemotherapy determined by the higher percentage of human Rh-123(dull) CD45+ cells in bone marrow of mice. CONCLUSION: Our results demonstrated successful chemoprotection against myelosuppression in mice by MDR1-transduced repopulating human hematopoietic cells with an optimized transduction protocol.