Experimental approaches to derive CD34+ progenitors from human and nonhuman primate embryonic stem cells

Traditionally, CD34 positive cells are predominantly found in the umbilical cord and bone marrow, thus are considered as hematopoietic progenitors. Increasing evidence has suggested that the CD34+ cells represent a distinct subset of cells with enhanced progenitor activity; CD34 is a general marker of progenitor cells in a variety of cell types. Because the CD34 protein shows expression early on in hematopoietic and vascular-associated tissues, CD34+ cells have enormous potential as cellular agents for research and for clinical cell transplantation. Directed differentiation of embryonic stem cells will give rise to an inexhaustible supply of CD34+ cells, creating an exciting approach for biomedical research and for regenerative medicine. Here, we review the main methods that have been published for the derivation of CD34+ cells from embryonic stem cells; specifically those approaches the human and nonhuman primate stem cells. We summarize current status of this field, compare the methods used, and evaluate the issues in translating the bench science to bedside therapy

A preliminary timeline of the midbrain development in the Monodelphis Domestica animal model

Introduction: The Brazilian short-tailed opossum (Monodelphis Domestica) is an understudied animal model compared to the Mus musculus that has been identified as a perfect candidate to study neurodevelopment (Baggott, L. & Moore, H., 1990). What makes the Monodelphis Domestica a perfect specimen for neurodevelopment is that the embryo develops outside the pouch of the mother providing easy noninvasive access to track changes across different developmental stages (Mate et al., 1994). Objective: The objective of the study is to compare the area and volume in the development of the Monodelphis’s midbrain across three different developmental stages. Our research is beneficial because it facilitates the study of neurodevelopmental mental health disorders and its impact in the brain. Methods: We utilized ImageJ and Zen software to perform the volumetric and area analysis of these stages. To conduct a volumetric analysis a Volume Macro code was used in ImageJ software. The area analysis was completed using Zen software. A descriptive analysis was used to compare the differences in area and volume across the developmental stages

Differential Expression of Intestinal Genes in Opossums with High and Low Responses to Dietary Cholesterol

High and low responding opossums (Monodelphis domestica) differ in their plasma very low density lipoprotein and low density lipoprotein (VLDL+LDL) cholesterol concentrations when they consume a high cholesterol diet, which is due in part to absorption of a higher percentage of dietary cholesterol in high responders. We compared the expression of a set of genes that influence cholesterol absorption in high and low responders fed a basal or a high cholesterol and low fat (HCLF) diet. Up-regulation of the ABCG5, ABCG8, and IBABP genes by the HCLF diet in high and low responders may reduce cholesterol absorption to maintain cholesterol homeostasis. Differences in expression of the phospholipase genes (PLA2 and PLB) and phospholipase activity were associated with differences in cholesterol absorption when opossums were fed cholesterol-enriched diets. Higher PLA2 and PLB mRNA levels and higher phospholipase activity may increase cholesterol absorption in high responders by enhancing the release of cholesterol from bile salt micelles for uptake by intestinal cells

Vertebrate endothelial lipase: comparative studies of an ancient gene and protein in vertebrate evolution

Endothelial lipase (gene: LIPG; enzyme: EL) is one of three members of the triglyceride lipase family that contributes to lipoprotein degradation within the circulation system and plays a major role in HDL metabolism in the body. In this study, in silico methods were used to predict the amino acid sequences, secondary and tertiary structures, and gene locations for LIPG genes and encoded proteins using data from several vertebrate genome projects. LIPG is located on human chromosome 18 and is distinct from other human 'neutral lipase' genes, hepatic lipase (gene: LIPC; enzyme: HL) and lipoprotein lipase (gene: LPL; enzyme: LPL) examined. Vertebrate LIPG genes usually contained 10 coding exons located on the positive strand for most primates, as well as for horse, bovine, opossum, platypus and frog genomes. The rat LIPG gene however contained only 9 coding exons apparently due to the presence of a 'stop' codon' within exon 9. Vertebrate EL protein subunits shared 58-97% sequence identity as compared with 38-45% sequence identities with human HL and LPL. Four previously reported human EL N-glycosylation sites were predominantly conserved among the 10 potential N-glycosylation sites observed for the vertebrate EL sequences examined. Sequence alignments and identities for key EL amino acid residues were observed as well as conservation of predicted secondary and tertiary structures with those previously reported for horse pancreatic lipase (PL) (Bourne et al. 1994). Several potential sites for regulating LIPG gene expression were observed including CpG islands near the LIPG gene promoter and a predicted microRNA binding site near the 3'-untranslated region. Promoter regions containing functional polymorphisms that regulate HDL cholesterol in baboons were conserved among primates but not retained between primates and rodents. Phylogenetic analyses examined the relationships and potential evolutionary origins of the vertebrate LIPG gene subfamily with other neutral triglyceride lipase gene families, LIPC and LPL. It is apparent that the triglyceride lipase ancestral gene for the vertebrate LIPG gene predated the appearance of fish during vertebrate evolution[500 million years ago.Full Tex

A Neural Comparison Between Mus Musculus and Monodelphis Domestica

Mus Musculus is one of the first and widely used animal models in neuroscience. There are many reasons that Mus Musculus is used for research including, short generation length and large litters, but the most important reason is their mammalian brain. Another animal that is gaining interest as an animal model is the Monodelphis Domestica. The Monodelphis Domestica is a marsupial, pups are born underdeveloped and move onto the underbelly of their mothers until they reach a more mature age. One difference is the Monodelphis ventricle size is much larger in the forebrain area. Another difference is the formation of the corpus callosum. In the mouse brain, the corpus callosum forms and fuses before the hippocampus compared to the possum where the corpus callosum is formed more posterior to the formation of the hippocampus. The corpus callosum of the Monodelphis is less prominent than the anterior commissure. In the mouse brain, the majority of the nerve fibers are found in the corpus callosum as opposed to the anterior commissure. The corpus callosum allows communication between both hemispheres of the brain. In the mus musculus, the hippocampus is well defined and begins formation after the formation of the corpus callosum. In the Monodelphis, the hippocampus is not as defined. The mus musculus is a social animal, the more defined hippocampus could be an evolutionary improvement for social interaction. The Monodelphis is a more territorial and isolated species. Looking at the differences between the two, can further knowledge into the behavioral differences

Investigating Monodelphis Domestica as an Alternative to the Mus Musculus as an Animal Model

Background: Mus Musculus is one of the first and one of the most widely used animal models in current neuroscience literature (Phifer-Riley & Nachmann, 2015). However, the research community needs alternatives to rodent models to study the mammalian brain. Research is needed to see if antibodies that target tyrosine hydroxylase, which are well researched in mice, can also be used to study the Monodelphis domestica brain. Methods: Following transcardial perfusions and brain extractions, mouse and opossum brains were processed and stained for tyrosine hydroxylase (and with Nissl). Opossum brains will then be sliced and processed using IHC methods to compare two TH antibodies (EMD Millipore and Pelfreeze). Results: Differences include that the Monodelphis has a much larger ventricle in the forebrain area and the mouse brain corpus callosum forms and fuses before the hippocampus compared to the opossum brain, where these fibers are formed more posterior to the formation of the hippocampus. The corpus callosum of the Monodelphis is also less prominent than the anterior commissure. The results of the different antibodies will be presented at the symposium. Conclusions: Although there are differences between the mouse and the opossum brain, there are also many similarities. Further research is needed to determine what these differences could mean in behavior and cognition. Both EMD Millipore and Pelfreeze make TH antibodies that have been looked at in mice and replicated. More research is needed to determine if the antibodies can be used for other animals, including the Monodelphis

The impact of social isolation on the Neural Pathways of Dopamine Neurons in the Ventral Tegmental Area (VTA) and the Nucelus Accumbens (NAc): Implications for the treatment of depression, anxiety, and drug addiction.

As the literature on the Monodelphis domestica continues to grow, it is important to contribute to the knowledge base regarding neural pathways and their role in social behavior in this species. Previous studies have provided evidence that increased activity in ventral tegmental area (VTA) dopamine neurons were associated with more social activity in mice. It is also known that in traditional rodent models, the Nucleus Accumbens (NAcc) is implicated in interaction reward processes like motivation; however, more research is needed to elucidate the role of the NAcc in social behavior of the M. domestica. The present study was designed to address the knowledge gap regarding the brain and social behavior using M. domestica as an animal model. Using immunohistochemistry, we characterized the expression of Tyrosine Hydroxylase (TH), a marker for dopamine neurons, in both the VTA and the NAc of M. domestica and determined that the pattern of TH expression is similar to what is observed in rodents. Next, the expression of TH in opossums that were exposed to a social stimulus were compared to TH levels in animals that were not exposed to a social stimulus, confirming an effect of isolation on TH immunoreactivity. Social stimuli were provided by housing the opossums in groups of 2-3 same-sex partners or by themselves in their cages. Given that Monodelphis is a model for neurodevelopmental research, this study could serve as the first to look at neurotransmitters that are associated with social behavior in an animal model that is not widely studied. A goal of this presentation is to better inform clinicians about the possible biological basis of social isolation and the negative symptoms associated with it. Using the data that was collected, we can begin to understand the biological markers that are implicated in human psychological disorders and find areas to target with different treatment modalities

Identification of baboon microRNAs expressed in liver and lymphocytes

<p>Abstract</p> <p>Background</p> <p>MicroRNAs (miRNAs) are small noncoding RNAs (~22 nucleotides) that regulate gene expression by cleaving mRNAs or inhibiting translation. The baboon is a well-characterized cardiovascular disease model; however, no baboon miRNAs have been identified. Evidence indicates that the baboon and human genomes are highly conserved; based on this conservation, we hypothesized that comparative genomic methods could be used to identify baboon miRNAs.</p> <p>Methods</p> <p>We employed an <it>in silico </it>comparative genomics approach and human miRNA arrays to identify baboon expressed miRNAs in liver (n = 6) and lymphocytes (n = 6). Expression profiles for selected miRNAs in multiple tissues were validated by RT-PCR.</p> <p>Results</p> <p>We identified <it>in silico </it>555 putative baboon pre-miRNAs, of which 41% exhibited 100% identity and an additional 58% shared more than 90% sequence identity with human pre-miRNAs. Some of these miRNAs are primate-specific and are clustered in the baboon genome like human miRNA clusters. We detected expression of 494 miRNAs on the microarray and validated expression of selected miRNAs in baboon liver and lymphocytes by RT-PCR. We also observed miRNA expression in additional tissues relevant to dyslipidemia and atherosclerosis. Approximately half of the miRNAs expressed on the array were not predicted <it>in silico </it>suggesting that we have identified novel baboon miRNAs, which could not be predicted using the current draft of the baboon genome.</p> <p>Conclusion</p> <p>We identified a subset of baboon miRNAs using a comparative genomic approach, identified additional baboon miRNAs using a human array and showed tissue-specific expression of baboon miRNAs. Our discovery of baboon miRNAs in liver and lymphocytes will provide resources for studies on the roles of miRNAs in dyslipidemia and atherosclerosis, and for translational studies.</p

Relief and recovery activities conducted by the Better Research, Better Life Foundation (BRBLF) in collaboration with the Caribbean Primate Research Center (CPRC)

BRBLF, a 501(c)(3) non‐profit organization, is dedicated to the advancement of global preclinical research while focusing on the responsible use of nonhuman primates. Its goal is to optimize the contribution of nonhuman primates to biomedical and behavioral research by fostering innovative collaborations, education, training, and outreach. Immediately after Hurricane Maria, BRBLF and CPRC leadership initiated an emergency plan and began to develop and implement disaster relief and research continuity solutions for Cayo Santiago and the Sabana Seca Field Station. The initial action was to provide satellite phones, which enabled CPRC staff to re‐establish stable communication with the mainland and to communicate the immediate needs regarding the stabilization of staff, monkeys, and facilities. BRBLF, with the support of the research community and philanthropic individuals and organizations, facilitated and funded the logistics to ship containers of essentials, including water, food, clothing, mattresses, medicine, solar lights, all‐terrain vehicles, floating docks, and a pickup truck. In December, the BRBLF and CPRC leadership met with the University of Puerto Rico\u27s President and its Chancellor of the Medical Sciences Campus; together they developed and announced a collaborative plan that highlights the building of a new, modern laboratory on Cayo Santiago. The facility is designed to withstand hurricane conditions; completion is expected in mid‐2019. BRBLF continues its commitment to raise funds and awareness for the invaluable and irreplaceable CPRC research resources