Project description:To study the effect of pregnancy on mouse mammary epithelial subpopulations, epthelial cells derived from virgin or pregnant (12.5 day pregnant) mice were isolated using fluorescence-activated cell sorting. After elimination of haematopoietic and endothelial cells, two distinct epithelial subpopulations were sorted using antibodies against CD29 and CD24. Based on the immunohistochemical phenotype, and in vivo and in vitro functional assays, these subpopulations were identified as mammary stem cell enriched (CD29hiCD24+) and luminal (CD29loCD24+) respectively (ref: Shackleton et al, Nature 2006). Microarray profiling was used to compare gene expression profiles of the two subpopulations in 12.5 day pregnant and virgin mice.
Project description:To study the effect of pregnancy on mouse mammary epithelial subpopulations, epthelial cells derived from virgin or pregnant (12.5 day pregnant) mice were isolated using fluorescence-activated cell sorting. After elimination of haematopoietic and endothelial cells, two distinct epithelial subpopulations were sorted using antibodies against CD29 and CD24. Based on the immunohistochemical phenotype, and in vivo and in vitro functional assays, these subpopulations were identified as mammary stem cell enriched (CD29hiCD24+) and luminal (CD29loCD24+) respectively (ref: Shackleton et al, Nature 2006). Microarray profiling was used to compare gene expression profiles of the two subpopulations in 12.5 day pregnant and virgin mice. For each biological replicate, mammary gland from virgin or 12.5 day pregnant FVB/NJ mice were collected and digested to obtain a single cell suspension. CD45-CD31-TER119- cells were then sorted based on the expression of cell surface markers CD24 and CD29. There were 4 pools of pregant mice and 3 pools of virgin mice.
Project description:Cross-species hybridization analysis of mammary glands during pregnancy and lactation. Results provide insight into putative conserved molecular mechanisms regulating mammary gland development. This study was performed to identify orthologous transcripts that are differentially co-expressed in the mammary gland at 2 stages of development (pregnancy and lactation) in wild type Sprague-Dawley rats. Key points are examined in a time series of Sprague Dawley rat mammary gland development, secretory activation and lactation. Triplicate rat (three biological replicates) at each time point were used for statistical power totalling 12 individual arrays in this study. Rats were as staged pregnant day 1 the day that post coital plug was observed, and similarly, lactation day 1 was the first day after birth. Whole mammary glands No. 4 (inguinal) were obtained from female rats at stages of development: virgin (adulthood, 14 wks of age), Pregnant (5 and 14 days of pregnancy) and Lactating (day 1 and 12 postpartum). The two-color (Cy5/Cy3) microarray experiment was designed to hybridize samples from each group against a common reference, a pool of RNA from mammary gland of three parous or virgin female rats.
Project description:The survival and reproductive success of animals depends on the ability to harmonize their external behaviors with their internal states. For example, females conduct numerous social programs that are distinctive to virgins compared to post-mated and/or pregnant individuals. In Drosophila, the fact that the post-mating switch is initiated by seminal factors implies the default state as virgin. Recently, we uncovered molecular and genetic control of the female virgin state. In particular, repression of the transcription factor Homothorax (Hth) by mir-iab-4/8 within the abdominal ventral nerve cord (VNC) is critical for unmated females to execute virgin behaviors. To elucidate new components of this regulatory circuit, we exploited mir-iab-4/8 deletion and hth-miRNA binding site mutants (hth[BSmut]) to elucidate doublesex (dsx) as a critical downstream factor. While Dsx has mostly been studied during sex-specific differentiation, its activities in neurons are little known. We find that accumulation of Dsx in the CNS is mutually exclusive with Hth, and downregulated in miRNA/hth[BSmut] mutants. Moreover, experimental suppression of Dsx in highly restricted sets of abdominal neurons abrogates female virgin conducts, in favor of mated behavioral programs. Thus, a double negative pathway in the VNC mediates the virgin behavioral state.
Project description:IgG was collected from virgin and pregnant listeria challenged mouse plasma. Polyclonal IgG was analyzed by reduction, alkylation, and LC-MS with top-down MS/MS (HCD and ETD)to look for glycosylation PTMs
Project description:Metastasis depends on the ability of tumor cells to establish a relationship with the newly seeded host tissue that is conducive to their survival and proliferation. Recent evidence suggests that tumor cells regulate their own dissemination by preparing permissive “metastatic niches” within host tissues. However, the factors that are implicated in rendering tissues permissive for metastatic tumor growth have yet to be fully elucidated. Breast tumors arising during pregnancy display highly aggressive behaviour and early metastatic proclivity, raising the possibility that pregnancy may constitute a physiological condition of permissiveness for tumor dissemination. We show that during murine gestation, both the rate and degree of metastatic tumor growth are enhanced irrespective of tumor type and that decreased natural killer (NK) cell activity is responsible for the observed increase in experimental metastasis. We identify gene expression changes in pregnant mouse lung and liver that bear striking similarity with reported pre-metastatic niche signatures and several of the up-regulated genes are indicative of myeloid-cell infiltration. We provide evidence, that CD11b+ Gr-1+ myeloid-derived suppressor cells accumulate in pregnant mice and exert an inhibitory effect on NK cell activity, thereby enhancing metastatic tumor growth. MDSC have never been evoked in the context of pregnancy and our observations suggest that they may represent a further shared mechanism of immune suppression occurring during gestation and tumor growth. Three chips were done per organ (liver/lung) and per condition (virgin/pregnant), with equal amounts of RNA from two mice pooled for one chip.