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Cancer immunotherapy has achieved impressive therapeutic effects in many cancers, while only a small subset of patients benefit from it and some patients even have experienced severe toxicity. It is urgent to develop a feasible large-cohort humanized mouse model to evaluate the pre-clinical efficacy and safety of cancer immunotherapy. Furthermore, developing potentially effective combination therapy between cancer immunotherapy and other therapies also needs humanized mouse model to adequately mimic clinical actual setting. Herein, we established a humanized mouse model engrafted with less human CD34

The function of prolactin in mammary gland development and lactation has been demonstrated in previous studies. However, the potential action of prolactin on mammary duct morphogenesis at mammary anlagen stage (E13.5˜15.5) has not been elucidated. Transplantation of mammary cells or tissue is an effective approach for the regeneration of damaged mammary gland. Defining the actions of prolactin stimulation on embryonic mammary anlagen has important implications for defining the role of prolactin in the poorly understood processes of mammary duct morphogenesis and regeneration. Here, we have employed the GFP-transgenic mouse model to examine the effects of prolactin on stem cell activity. Using in vitro prolactin stimulation and transplantation of E14.5 mouse mammary anlagen, we identified the influence of prolactin on their mammary repopulating ability. Furthermore, using immunofluorescence staining and microarray analysis, the influence of prolactin on cell characteristics and gene expression in mammary anlagen were also profiled. We also demonstrate that E14.5 mouse mammary anlagen possess mammary stem cells (MaSCs) which achieve mammary repopulation. Furthermore, we found that in vitro prolactin stimulation elevates MaSC activity and promotes the mammary repopulating ability of mammary anlagen. Finally, microarray and pathway analysis showed that MAPK, Akt and JAK-STAT signaling was activated by prolactin stimulation, and drove the mammary repopulation of mammary anlagen. We conclude that prolactin stimulation elevates the stem cell-dependent mammary repopulating ability of embryonic mammary anlagen.

Knockout of the ubiquitously expressed miRNA-17∼92 cluster in mice produces a lethal developmental lung defect, skeletal abnormalities, and blocked B lymphopoiesis. A shared target of miR-17∼92 miRNAs is the pro-apoptotic protein BIM, central to life-death decisions in mammalian cells. To clarify the contribution of miR-17∼92:Bim interactions to the complex miR-17∼92 knockout phenotype, we used a system of conditional mutagenesis of the nine Bim 3′ UTR miR-17∼92 seed matches. Blocking miR-17∼92:Bim interactions early in development phenocopied the lethal lung phenotype of miR-17∼92 ablation and generated a skeletal kinky tail. In the hematopoietic system, instead of causing the predicted B cell developmental block, it produced a selective inability of B cells to resist cellular stress; and prevented B and T cell hyperplasia caused by Bim haploinsufficiency. Thus, the interaction of miR-17∼92 with a single target is essential for life, and BIM regulation by miRNAs serves as a rheostat controlling cell survival in specific physiological contexts.

A patient-derived xenograft (PDX) approach, which relies on direct transplantation of tumor specimens into an immunocompromised animal, is a commonly used method for investigating tumor therapy predictions in vivo. This study evaluated influencing factors, including clinical, oncological, and genetic variables, for a pancreatic PDX model in mice. Tumor specimens were obtained from 121 patients with pancreatic ductal adenocarcinoma who underwent surgical resection at the Changhai Pancreatic Surgery Medical Center (Shanghai, China) between April 2016 and February 2017. Pancreatic cancer (PC) samples 3.5 cm in size was independently associated with xenograft formation rate. In addition, several enriched mutated genes within the VEGF pathway and higher microvessel density were found in the positive group (with xenograft) compared with the negative group (without xenograft). We concluded that tumor size and mutated VEGF pathway in PC are important factors affecting PDX model construction with NSG mice.-Guo, S., Gao, S., Liu, R., Shen, J., Shi, X., Bai, S., Wang, H., Zheng, K., Shao, Z., Liang, C., Peng, S., Jin, G. Oncological and genetic factors impacting PDX model construction with NSG mice in pancreatic cancer.

Summary Somatic cell reprogramming toward induced pluripotent stem cells (iPSCs) holds great promise in future regenerative medicine. However, the reprogramming process mediated by the traditional defined factors (OSMK) is slow and extremely inefficient. Here, we develop a combination of modified reprogramming factors (OySyNyK) in which the transactivation domain of the Yes-associated protein is fused to defined factors and establish a highly efficient and rapid reprogramming system. We show that the efficiency of OySyNyK-induced iPSCs is up to 100-fold higher than the OSNK and the reprogramming by OySyNyK is very rapid and is initiated in 24 hr. We find that OySyNyK factors significantly increase Tet1 expression at the early stage and interact with Tet1/2 to promote reprogramming. Our studies not only establish a rapid and highly efficient iPSC reprogramming system but also uncover a mechanism by which engineered factors coordinate with TETs to regulate 5hmC-mediated epigenetic control., Graphical Abstract, Highlights • A combination of modified reprogramming factors (OySyNyK) is developed • A highly efficient and rapid reprogramming system is established • TET1/2 proteins are involved in rapid iPSC induction by OySyNyK • OySyNyK factors coordinate with TET proteins to promote rapid reprogramming, The reprogramming process mediated by the traditional defined factors (OSMK) is slow and inefficient. Sun, Jin, Chen, and colleagues have developed a combination of modified reprogramming factors (OySyNyK) in which the transactivation domain of the Yes-associated protein is fused to defined factors and establish a highly efficient and rapid reprogramming system.

In addition to transactivation of interleukin-4 (IL-4), cellular muscular aponeurotic fibrosarcoma (c-Maf) enhances CD4 cell apoptosis by limiting Bcl-2 expression. The CD8 cells also express c-Maf and peripheral CD8 cell numbers are reduced in c-Maf transgenic mice, suggesting that c-Maf may influence CD8 cell survival in a manner similar to CD4 cells. Here we confirm that, similar to CD4 cells, c-Maf enhances CD8 cell susceptibility to apoptosis induced by multiple stimuli, independent of IL-4. However, unlike CD4 cells, c-Maf enhancement of apoptosis is independent of Bcl-2, suggesting that c-Maf uses other mechanisms to regulate CD8 cell apoptosis. Real-time reverse transcription-polymerase chain reaction reveals that the pro-apoptotic gene Caspase 6 is upregulated in c-Maf transgenic CD8 cells, suggesting that Caspase 6 is a novel c-Maf target gene. Luciferase reporter assays and site-directed mutagenesis reveal a functional c-Maf recognition element (MARE) within the first intron of Caspase 6. Binding of c-Maf to the MARE site is detectable by chromatin immunoprecipitation using non-transgenic T-cell lysates, so c-Maf can interact with the Caspase 6 MARE site in normal T cells. Furthermore, caspase 6 activity is increased among CD8 cells from c-Maf transgenic mice following T-cell receptor engagement. As expected, activity of the downstream caspases 3 and 7 is also increased. Consistent with the ability of caspase 6 to participate in positive feedback loops, cytochrome c release and caspase 8 activation are also increased. Together these results indicated that c-Maf increases CD8 cell sensitivity to apoptotic stimuli, at least in part, by direct transactivation of Caspase 6, providing increased substrate for Caspase 6-dependent apoptosis pathways.

A common complication associated with diabetes is painful or painless diabetic peripheral neuropathy (DPN). The mechanisms and determinants responsible for these peripheral neuropathies are poorly understood. Using both streptozotocin (STZ)-induced and transgene-mediated murine models of type 1 diabetes (T1D), we demonstrate that Transient Receptor Potential Vanilloid 1 (TRPV1) expression varies with the neuropathic phenotype. We have found that both STZ- and transgene-mediated T1D are associated with two distinct phases of thermal pain sensitivity that parallel changes in TRPV1 as determined by paw withdrawal latency (PWL). An early phase of hyperalgesia and a late phase of hypoalgesia are evident. TRPV1-mediated whole cell currents are larger and smaller in dorsal root ganglion (DRG) neurons collected from hyperalgesic and hypoalgesic mice. Resiniferatoxin (RTX) binding, a measure of TRPV1 expression is increased and decreased in DRG and paw skin of hyperalgesic and hypoalgesic mice, respectively. Immunohistochemical labeling of spinal cord lamina I and II, dorsal root ganglion (DRG), and paw skin from hyperalgesic and hypoalgesic mice reveal increased and decreased TRPV1 expression, respectively. A role for TRPV1 in thermal DPN is further suggested by the failure of STZ treatment to influence thermal nociception in TRPV1 deficient mice. These findings demonstrate that altered TRPV1 expression and function contribute to diabetes-induced changes in thermal perception.

The transcription factor c-Maf is critical for IL-4 production and the development of Th2 cells, which promote humoral immunity and protect against extracellular parasites. Yet, little else is known of c-Maf function in CD4 cells. Here, we identify a novel role for c-Maf in regulating susceptibility to apoptosis. Overexpression of c-Maf results in increased susceptibility of CD4 cells to apoptosis induced by multiple stimuli, including growth factor withdrawal, dexamethasone, irradiation, and TCR engagement. This effect is independent of Fas or p53; however, Bcl-2 expression is reduced in c-Maf Tg CD4 cells. Immunoprecipitation and Western blot analyses demonstrate that c-Maf–c-Myb complex formation is enhanced among T cells from c-Maf Tg mice compared to non-Tg littermates following TCR engagement. Unlike non-Tg T cells, c-Myb binding to the Bcl-2 promoter is not detectable in c-Maf Tg T cells by chromatin immunoprecipitation. In reporter assays, Bcl-2 promoter activity is reduced by c-Maf in a dose-dependent manner. Furthermore, transgene-mediated Bcl-2 expression corrects the apoptosis defect observed among c-Maf Tg CD4 cells. These data suggest that c-Maf can interact with c-Myb to reduce Bcl-2 expression, thereby limiting CD4 cell survival following TCR engagement.