24 research outputs found
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Dilated Blood and Lymphatic Microvessels, Angiogenesis, Increased Macrophages, and Adipocyte Hypertrophy in Lipedema Thigh Skin and Fat Tissue
Background and Aim. Lipedema is a common painful SAT disorder characterized by enlargement of fat primarily in the legs of women. Case reports of lipedema tissue samples demonstrate fluid and fibrosis in the interstitial matrix, increased macrophages, and adipocyte hypertrophy. The aims of this project are to investigate blood vasculature, immune cells, and structure of lipedema tissue in a cohort of women. Methods. Forty-nine participants, 19 controls and 30 with lipedema, were divided into groups based on body mass index (BMI): Non-Obese (BMI 20 to <30kg/m(2)) and Obese (BMI 30 to <40kg/m(2)). Histological sections from thigh skin and fat were stained with H&E. Adipocyte area and blood vessel size and number were quantified using ImageJ software. Markers for macrophages (CD68), mast cells (CD117), T cells (CD3), endothelial cells (CD31), blood (SMA), and lymphatic (D2-40 and Lyve-1) vessels were investigated by IHC and IF. Results. Non-Obese Lipedema adipocyte area was larger than Non-Obese Controls (p=0.005) and similar to Obese Lipedema and Obese Controls. Macrophage numbers were significantly increased in Non-Obese (p<0.005) and Obese (p<0.05) Lipedema skin and fat compared to Control groups. No differences in T lymphocytes or mast cells were observed when comparing Lipedema to Control in both groups. SMA staining revealed increased dermal vessels in Non-Obese Lipedema patients (p<0.001) compared to Non-Obese Controls. Lyve-1 and D2-40 staining showed a significant increase in lymphatic vessel area but not in number or perimeter in Obese Lipedema participants (p<0.05) compared to Controls (Obese and Non-Obese). Areas of angiogenesis were found in the fat in 30% of lipedema participants but not controls. Conclusion. Hypertrophic adipocytes, increased numbers of macrophages and blood vessels, and dilation of capillaries in thigh tissue of non-obese women with lipedema suggest inflammation, and angiogenesis occurs independent of obesity and demonstrates a role of altered vasculature in the manifestation of the disease.Lipedema Foundation; University of Arizona College of Medicine TREAT ProgramOpen access journalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]
ECM microenvironment unlocks brown adipogenic potential of adult human bone marrow-derived MSCs
Key to realizing the diagnostic and therapeutic potential of human brown/brite adipocytes is the identification of a renewable, easily accessible and safe tissue source of progenitor cells, and an efficacious in vitro differentiation protocol. We show that macromolecular crowding (MMC) facilitates brown adipocyte differentiation in adult human bone marrow mesenchymal stem cells (bmMSCs), as evidenced by substantially upregulating uncoupling protein 1 (UCP1) and uncoupled respiration. Moreover, MMC also induced ‘browning’ in bmMSC-derived white adipocytes. Mechanistically, MMC creates a 3D extracellular matrix architecture enshrouding maturing adipocytes in a collagen IV cocoon that is engaged by paxillin-positive focal adhesions also at the apical side of cells, without contact to the stiff support structure. This leads to an enhanced matrix-cell signaling, reflected by increased phosphorylation of ATF2, a key transcription factor in UCP1 regulation. Thus, tuning the dimensionality of the microenvironment in vitro can unlock a strong brown potential dormant in bone marrow
MCAM: Multiple Clustering Analysis Methodology for Deriving Hypotheses and Insights from High-Throughput Proteomic Datasets
Advances in proteomic technologies continue to substantially accelerate capability for generating experimental data on protein levels, states, and activities in biological samples. For example, studies on receptor tyrosine kinase signaling networks can now capture the phosphorylation state of hundreds to thousands of proteins across multiple conditions. However, little is known about the function of many of these protein modifications, or the enzymes responsible for modifying them. To address this challenge, we have developed an approach that enhances the power of clustering techniques to infer functional and regulatory meaning of protein states in cell signaling networks. We have created a new computational framework for applying clustering to biological data in order to overcome the typical dependence on specific a priori assumptions and expert knowledge concerning the technical aspects of clustering. Multiple clustering analysis methodology (‘MCAM’) employs an array of diverse data transformations, distance metrics, set sizes, and clustering algorithms, in a combinatorial fashion, to create a suite of clustering sets. These sets are then evaluated based on their ability to produce biological insights through statistical enrichment of metadata relating to knowledge concerning protein functions, kinase substrates, and sequence motifs. We applied MCAM to a set of dynamic phosphorylation measurements of the ERRB network to explore the relationships between algorithmic parameters and the biological meaning that could be inferred and report on interesting biological predictions. Further, we applied MCAM to multiple phosphoproteomic datasets for the ERBB network, which allowed us to compare independent and incomplete overlapping measurements of phosphorylation sites in the network. We report specific and global differences of the ERBB network stimulated with different ligands and with changes in HER2 expression. Overall, we offer MCAM as a broadly-applicable approach for analysis of proteomic data which may help increase the current understanding of molecular networks in a variety of biological problems.National Institutes of Health (U.S.) (NIH-U54-CA112967 )National Institutes of Health (U.S.) (NIH-R01-CA096504
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Development of approaches for immunotherapy by chimeric antigen receptor modified hematopoietic stem cell transfer
Cancer is an uncontrolled growth of the body's own cells. While cancer rates increase with age, this disease afflicts both young and old. Traditional cancer therapy has had three major facets: 1) chemotherapy, which can non-specifically damage healthy tissue, 2) radiation, which can make some types of cancer more likely in the future, and 3) surgery, which can be physically traumatic and is not effective in removing unseen microtumors or circulating metastases. Immunotherapy, by its very nature, is drastically different. Immunotherapy seeks to employ cells or molecules from the immune system, in their original or a modified form, to augment, assist or replace missing elements of the native functioning immune system. Our immunotherapeutic approach has been to develop novel chimeric antigen receptors (CAR) and deliver the engineered transgene into hematopoietic stem cells (HSC). We have developed a novel single chain TCR (scTCR) in which the TCR V-alpha and V-beta segments are joined by a flexible linker. In addition to our scTCR we developed a single chain antibody molecule (scFv) to increase avidity to the tumor antigen and avoid the potential limitation of MHC restriction. Our lab has previously developed a signaling cassette based on the CD3 zeta chain, CD28 and p56Lck proteins which are prominent in the T-cell signaling pathway. The single chain specificities are linked to the signaling cassette that we have shown to function in T-cells. With specificity and signaling coupled, the chimeric antigen receptor can be transduced into hematopoietic stem cells (HSC) via a lentivirus vector. This adoptive immunotherapy can potentially eliminate malignant cells or supplement traditional therapies by providing engineered specificity and a useful method to transfer and expand tumor specific T-cells. We show in this study that the CAR can be delivered effectively to HSC and that the introduced transgene is expressed in multiple cell lineages. We also have developed a novel method of increasing lentiviral transduction efficiency. Both transduced fraction of cells and overall expression can be increased by proper timing and coordination of cell growth, cell cycle phase, vector addition and treatment with heat shock
Comparison of Manual versus Automated SARS-CoV-2 Rapid Antigen Testing in Asymptomatic Individuals
The SARS-CoV-2 pandemic has infected more than 770 M people and killed more than 6.9 M persons worldwide. In the USA, as of August 2023, it has infected more than 103 M people while causing more than 1.1 M deaths. During a pandemic, it is necessary to rapidly identify those individuals infected with the virus so that disease transmission can be stopped. We examined the sensitivity of the Quidel Rapid Antigen test on the manual Sofia 2 platform and the Beckman-Coulter antigen test on the automated DxI-800 system for use in screening asymptomatic individuals at the University of Arizona from March through May 2021. A total of 378 asymptomatic subjects along with 176 validation sets of samples in 23 independent experiments were assessed in side-by-side antigen testing using both assays. Nasal swabs and saliva were used as viral sources. Manual testing (Quidel) was compared with automated testing (Beckman) methods for cost and efficiency. Limit dilution of viral antigen spiked samples was performed to determine sensitivity to antigen load by the tests. The results between the two tests were found to be concordant. Both tests were comparable in terms of detecting low numbers of positive subjects in the asymptomatic population. A concordance of 98% was observed between the two tests. Experiments also demonstrated that saliva specimens were an acceptable viral source and produced comparable results for each test. Overall, the two methods were interchangeable
Long-Term Biobanking of Intact Tissue from Lipoaspirate
Autologous fat grafting has now been extensively and successfully performed for more than two decades. Although most adipose grafts and adipose-derived MSC therapies are done with fresh tissue, cryopreservation of tissue allows for much greater flexibility of use. Over the course of five years, 194 cryopreserved adipose samples were thawed and then returned to the collecting physician for subsequent autologous applications. Samples were stored with a mean cryogenic storage time of 9.5 months, with some samples being stored as long as 44 months. The volumes of tissue stored varied from 12 cc to as large as 960 cc. Upon thawing, the volume of recovered whole adipose tissue averaged 67% of the original amount stored for all samples, while the samples that were stored for longer than one year averaged 71%. Recovery was not found to be a function of length of time in cryopreservation. No significant relationship was found between tissue recovery and patient age. While an average recovery of 67% of volume frozen indicates that the use of banked and thawed tissue requires a larger amount of sample to be taken from the patient initially, an experienced clinician easily accomplishes this requirement. As cryopreservation of adipose tissue becomes more commonplace, physicians will find it helpful to know the amount and quality of tissue that will be available after thawing procedures
Improving 2D and 3D skin in vitro models, using macromolecular crowding
The glycoprotein family of collagens represents the main structural proteins in the human body, and are key components of biomaterials used in modern tissue engineering. A technical bottleneck is the deposition of collagen in vitro, as it is notoriously slow, resulting in sub-optimal formation of connective tissue and subsequent tissue cohesion, particularly in skin models. Here, we describe a method which involves the addition of differentially-sized sucrose co-polymers to skin cultures to generate macromolecular crowding (MMC), which results in a dramatic enhancement of collagen deposition. Particularly, dermal fibroblasts deposited a significant amount of collagen I/IV/VII and fibronectin under MMC in comparison to controls.
The protocol also describes a method to decellularize crowded cell layers, exposing significant amounts of extracellular matrix (ECM) which were retained on the culture surface as evidenced by immunocytochemistry. Total matrix mass and distribution pattern was studied using interference reflection microscopy. Interestingly, fibroblasts, keratinocytes and co-cultures produced cell-derived matrices (CDM) of varying composition and morphology. CDM could be used as "bio-scaffolds" for secondary cell seeding, where the current use of coatings or scaffolds, typically from xenogenic animal sources, can be avoided, thus moving towards more clinically relevant applications.
In addition, this protocol describes the application of MMC during the submerged phase of a 3D-organotypic skin co-culture model which was sufficient to enhance ECM deposition in the dermo-epidermal junction (DEJ), in particular, collagen VII, the major component of anchoring fibrils. Electron microscopy confirmed the presence of anchoring fibrils in cultures developed with MMC, as compared to controls. This is significant as anchoring fibrils tether the dermis to the epidermis, hence, having a pre-formed mature DEJ may benefit skin graft recipients in terms of graft stability and overall wound healing. Furthermore, culture time was condensed from 5 weeks to 3 weeks to obtain a mature construct, when using MMC, reducing costs
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Analysis of High-Throughput Processing Methods for Peripheral Blood Cell Isolation
12 month embargo; published online: 13 June 2022This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]