Investigating the effects of stem cell therapies in experimental models of renal ischemia-reperfusion injury

The incidence of end-stage renal disease is increasing in Western Society. Renal transplantation is known to be the optimal treatment for ESRD, being associated with significant reduction in morbidity, mortality for patients and cost for wider society when compared to remaining on dialysis. Unfortunately, the growing number of patients listed for renal transplantation has occurred without a matched supply in the number of suitable organs. This has led to longer average waiting times for increased numbers of patients, who consequently suffer adverse outcomes at considerable cost to the National Health Service as a result of organ shortage. One strategy employed by clinicians to meet demand for organs has been to transplant ‘suboptimal’ kidneys’ historically rejected as unsuitable for transplantation, which are usually retrieved from older and less fit donors. Sometimes referred to as ‘extended criteria’ or ‘marginal kidneys’, such allografts are more prone to damage in the peri-transplantation period, with the major pathological process recognised to be ischemia-reperfusion injury (IRI). Although functioning ‘marginal’ allografts have been shown to confer benefit to recipients, early transplant failure is associated with negative outcomes. Consequently, there is a real need to develop treatments to mitigate renal IRI, especially since the use of ‘marginal’ kidneys is likely to increase. Stem cell therapy has been shown to protect solid organs from IRI in a number of different animal models. Consequently, there is great interest in researching the ability of stem cell-based therapies to ameliorate solid organ damage and perhaps to encourage organ regeneration. However, debate exists regarding the exact mechanism by which stem cells produce their effects. Some researchers suggest that stem cells directly differentiate to replace specialised cell types in damage organs. Other investigators conclude that stem cells produce their effects in a paracrine fashion via the release of extracellular vesicles with the horizontal transfer of genetic material between cells. Unfortunately, no therapies are currently in widespread use to reduce damage to allografts in the peri-transplant period. In part, this reflects the lack of robust small animal models for screening potential renal IRI therapies before testing in large animal models. Furthermore, clinical application has been limited by safety concerns, and particularly by the risk of stem cells undergoing malignant transformation and subsequent tumour formation in recipients. However, investigators hypothesise that the use of stem cell-derived, extracellular vesicles may confer similar beneficial therapeutic efficacy, but lack many of the side effects associated with stem cells themselves. This thesis describes experiments in which stem cell-based therapies are tested in conventional and novel animal models of renal IRI and renal transplantation. In Chapter 3, initial experiments unexpectedly demonstrated the potential of ex vivo expanded stem cells to undergo malignant change and induce tumour formation in recipient animals. Therefore, the subsequent research investigated the effects of freshly isolated stem cells or those of novel extracellular vesicle preparations. In Chapter 4, experiments unexpectedly demonstrated the shortcomings of a conventional rat model of renal IRI. Therefore, Chapter 5 describes the development of a novel rat of model of renal IRI, in which stem cell-based therapies may be tested. Using this animal model, Chapters 6 and Chapter 7 describe the investigation of novel stem cell-based therapies and their effects on renal IRI. Some of these treatments were found to protect kidneys from IRI damage with preservation of renal function and structure in the medium to long-term. Chapter 8 describes a rat model of renal transplantation, in which therapies were investigated after being screened for efficacy in the novel rat IRI model. Although no functional difference was demonstrated, renal histology was preserved by treatment, although the mechanisms by which this effect occurred remain unclear. These findings suggest that stem cells and their extracellular vesicles have the potential to reduce peri-transplantation renal IRI and hence improve long-term outcomes of ‘marginal’ allografts. However, clinical translation requires the long-term efficacy and safety of these novel therapies to be investigated in large animal models of renal transplantation, before further testing in pilot studies

Disease Mongering Is Now Part of the Global Health Debate

Ray Moynihan and colleagues, who organized the world's first international conference on disease mongering in 2006, discuss its subsequent impact

New Distributional Records and Natural History Notes on Selected Fishes from Arkansas

This report documents new records on the distribution of selected fishes from Arkansas and provides notes on their natural history. We document new geographic records for 21 species within 8 families in 12 counties of the state. Most importantly we have included new records for fishes ranked S1, S2 or S3 in the state by NatureServe and several Species of Special Concern by the Arkansas Game and Fish Commission (AGFC). Additional collections of fishes in the state will undoubtedly provide more records especially with the use of electroshocking devices as has been shown herein

Identification of molecular markers of delayed graft function based on the regulation of biological ageing

Introduction: Delayed graft function is a prevalent clinical problem in renal transplantation for which there is no objective system to predict occurrence in advance. It can result in a significant increase in the necessity for hospitalisation post-transplant and is a significant risk factor for other post-transplant complications. Methodology: The importance of microRNAs (miRNAs), a specific subclass of small RNA, have been clearly demonstrated to influence many pathways in health and disease. To investigate the influence of miRNAs on renal allograft performance post-transplant, the expression of a panel of miRNAs in pre-transplant renal biopsies was measured using qPCR. Expression was then related to clinical parameters and outcomes in two independent renal transplant cohorts. Results: Here we demonstrate, in two independent cohorts of pre-implantation human renal allograft biopsies, that a novel pre-transplant renal performance scoring system (GRPSS), can determine the occurrence of DGF with a high sensitivity (>90%) and specificity (>60%) for donor allografts pre-transplant, using just three senescence associated microRNAs combined with donor age and type of organ donation. Conclusion: These results demonstrate a relationship between pre-transplant microRNA expression levels, cellular biological ageing pathways and clinical outcomes for renal transplantation. They provide for a simple, rapid quantitative molecular pre-transplant assay to determine post-transplant allograft function and scope for future intervention. Furthermore, these results demonstrate the involvement of senescence pathways in ischaemic injury during the organ transplantation process and an indication of accelerated bio-ageing as a consequence of both warm and cold ischaemia

Gertrude Robinson Correspondence

Entries include brief biographical information, a typed biography, years of typed and handwritten letters on plain and graph paper stationery, expressive accounts of time spent at her summer home on Orr\u27s Island, Maine, a typed plain postcard explaining that she had written a recent book draft after a New York bus accident, correspondence concerning her work with Books Across the Sea aiding the visiting Cornish historian Rowse in research with Day of the English-Speaking Union, and a typed letter from the Tompkins Square House on Community Service Center stationery from Bollettino providing information on Robinson\u27s recent passing

Tuberculosis Treatment in HIV Infected Ugandans with CD4 Counts >350 Cells/mm3 Reduces Immune Activation with No Effect on HIV Load or CD4 Count

Both HIV and TB cause a state of heightened immune activation. Immune activation in HIV is associated with progression to AIDS. Prior studies, focusing on persons with advanced HIV, have shown no decline in markers of cellular activation in response to TB therapy alone.) and pulmonary TB. HIV load, CD4 count, and markers of immune activation (CD38 and HLA-DR on CD4 and CD8 T cells) were measured prior to starting, during, and for 6 months after completion of standard 6 month anti-tuberculosis (TB) therapy in 38 HIV infected Ugandans with smear and culture confirmed pulmonary TB.Expression of CD38, and co-expression of CD38 and HLA-DR, on CD8 cells declined significantly within 3 months of starting standard TB therapy in the absence of anti-retroviral therapy, and remained suppressed for 6 months after completion of therapy. In contrast, HIV load and CD4 count remained unchanged throughout the study period.

Whole Blood Interferon-Gamma Responses to Mycobacterium tuberculosis Antigens in Young Household Contacts of Persons with Tuberculosis in Uganda

Due to immunologic immaturity, IFN-gamma-producing T cell responses may be decreased in young children compared to adults, thus we hypothesized that IFN-gamma responses to mycobacterial antigens in household contacts exposed to Mycobacterium tuberculosis (Mtb) would be impaired in young children relative to adults. The objective of this study was to compare whole blood IFN-gamma production in response to mycobacterial antigens between children and adults in Uganda.We studied household contacts of persons with culture-positive pulmonary tuberculosis (TB) enrolled in a cohort study conducted in Kampala, Uganda. Whole blood IFN-gamma production in response to Mtb culture-filtrate antigens was measured by ELISA and compared between infants (<2 years old, n = 80), young children (2 <5 years old, n = 216), older children (5 <15 years old, n = 443) and adults (> or =15 years old, n = 528). We evaluated the relationship between IFN-gamma responses and the tuberculin skin test (TST), and between IFN-gamma responses and epidemiologic factors that reflect exposure to Mtb, and the effect of prior BCG vaccination on IFN-gamma responses. Young household contacts demonstrated robust IFN-gamma responses comparable to those of adults that were associated with TST and known risk factors for infection. There was no effect of prior BCG immunization on the IFN-gamma response.Young children in a TB endemic setting can mount robust IFN-gamma responses generally comparable to those of adults, and as in adults, these responses correlated with the TST and known epidemiologic risk factors for Mtb infection

Kenneth Lewis Roberts Correspondence

Entries include brief biographical information, a typed biography, typed and handwritten correspondence on personal stationery from Kennebunk Beach, Maine, including a humorous letter in 1933 concerning the Society for Helping Maine Literature, his belief that the author collection was in need of Arnoldiana such as a donated pike head handmade by Arnold\u27s blacksmiths for the attack on Quebec, the manuscript of Arundel sent to be opened after publication and loaned to Leonard for Doubleday Doran and Company and a surprising Western Union telegram requesting permanent loan of the manuscript for MIT, handwritten and typed correspondence from Roberts in Italy including a handwritten artistic postcard from his wife, numerous biographical newspaper review clippings with photographic images, book synopses, and a poem for Theodore Roosevelt who could remember neither the author nor title of the book he was reading, a research question concerning Maine people on cookery, notes through the years concerning his friends, the staff at Doubleday, historians, libraries, and librarians as well as transition at the Maine Development Commission, correspondence with Mary A. Benjamin on Walter R. Benjamin, Autographs, stationery and a postcard concerning the possible sale of a copy of a Maine land grant document, a gift instead from Roberts of his vellum copy of the Trelawny-Goodyear grant of 1631, and the reply of Stubbs from the Maine State Library on receipt of this copy of the Casco Bay land grant

GGPS1-associated muscular dystrophy with and without hearing loss

Ultra-rare biallelic pathogenic variants in geranylgeranyl diphosphate synthase 1 (GGPS1) have recently been associated with muscular dystrophy/hearing loss/ovarian insufficiency syndrome. Here, we describe 11 affected individuals from four unpublished families with ultra-rare missense variants in GGPS1 and provide follow-up details from a previously reported family. Our cohort replicated most of the previously described clinical features of GGPS1 deficiency; however, hearing loss was present in only 46% of the individuals. This report consolidates the disease-causing role of biallelic variants in GGPS1 and demonstrates that hearing loss and ovarian insufficiency might be a variable feature of the GGPS1-associated muscular dystrophy

Prokineticin 1 Induces Inflammatory Response in Human Myometrium: A Potential Role in Initiating Term and Preterm Parturition

The infiltration of human myometrium and cervix with leukocytes and the formation of a pro-inflammatory environment within the uterus have been associated with the initiation of both term and preterm parturition. The mechanism regulating the onset of this pro-inflammatory cascade is not fully elucidated. We demonstrate that prokineticin 1 (PROK1) is up-regulated in human myometrium and placenta during labor. The expression of PROK1 receptor remains unchanged during labor and is abundantly expressed in the myometrium. Gene array analysis identified 65 genes up-regulated by PROK1 in human myometrium, mainly cytokines and chemokines, including IL-1β, chemokine C-C motif ligand 3, and colony-stimulating factor 3. In addition, we demonstrate that PROK1 increases the expression of chemokine C-C motif ligand 20, IL-6, IL-8, prostaglandin synthase 2, and prostaglandin E2 and F2α secretion. The treatment of myometrial explants with 100 ng/mL of lipopolysaccharide up-regulates the expression of PROK1, PROK1 receptor, and inflammatory mediators. The infection of myometrial explants with lentiviral microRNA targeting PROK1, preceding treatment with lipopolysaccharide, reduces the expression of inflammatory genes. We propose that PROK1 is a novel inflammatory mediator that can contribute to the onset of human parturition at term and partially mediate premature onset of inflammatory pathways during bacterial infection