Understanding Mesangial Pathobiology in AL-Amyloidosis and Monoclonal Ig Light Chain Deposition Disease

Patients with plasma cell dyscrasias produce free abnormal monoclonal Ig light chains that circulate in the blood stream. Some of them, termed glomerulopathic light chains, interact with the mesangial cells and trigger, in a manner dependent of their structural and physicochemical properties, a sequence of pathological events that results in either light chain–derived (AL) amyloidosis (AL-Am) or light chain deposition disease (LCDD). The mesangial cells play a key role in the pathogenesis of both diseases. The interaction with the pathogenic light chain elicits specific cellular processes, which include apoptosis, phenotype transformation, and secretion of extracellular matrix components and metalloproteinases. Monoclonal light chains associated with AL-Am but not those producing LCDD are avidly endocytosed by mesangial cells and delivered to the mature lysosomal compartment where amyloid fibrils are formed. Light chains from patients with LCDD exert their pathogenic signaling effect at the cell surface of mesangial cells. These events are generic mesangial responses to a variety of adverse stimuli, and they are similar to those characterizing other more frequent glomerulopathies responsible for many cases of end-stage renal disease. The pathophysiologic events that have been elucidated allow to propose future therapeutic approaches aimed at preventing, stopping, ameliorating, or reversing the adverse effects resulting from the interactions between glomerulopathic light chains and mesangium.

[Internationalization, science and health: global regenerative medicine and the parallel markets]

Regenerative medicine involves a paradigm change due to organism regeneration at cellular and tissue level - a controversial contemporary issue and difficult to regulate. This article presents a summary of the main scientific, economic, social and regulatory global trends, analyzed according to relevant theoretical dilemmas in medical anthropology and in the sociology of science and health. This is especially true of the construction of a 'collective frame of reference' on the new biological and ontological entities, the shaping of biological citizenship, and governance through uncertainty. Empirical evidence is also presented on a key aspect in regulation and governance, namely the emergence of a new transnational demand in health research through the establishment of parallel markets for ova and experimental cellular therapies. Qualitative data collected for a broader research paper is analyzed, as well as journal reviews and information gathered during interviews with international leaders. The paper concludes with a discussion on the importance on international governance of clinical trials and on further exploration, towards a multilevel harmonization of a diversity of normative practices.

Progenitor cell secretory products exert additive renoprotective effects when combined with ace inhibitors in experimental CKD

Hypothesis/introduction:

Renal fibrovascular injury often persists in chronic kidney disease patients treated with renin-angiotensin system blockers. Intriguingly, early outgrowth cell-derived factor infusion also inhibits chronic renal injury. We sought to determine whether early outgrowth cell-derived factor administration provides further renoprotection when added to renin-angiotensin system blockade.

Materials and methods:

Conditioned medium was generated by incubating rat early outgrowth cells with serum-free endothelial basal medium-2 to collect their secreted factors. Subtotal nephrectomy rats received enalapril 0.5 mg/L in drinking water or placebo, beginning 8 weeks post-surgery. Four weeks later, enalapril-treated rats received intravenous injections of either conditioned medium or control endothelial basal medium-2 for 2 weeks. Glomerular filtration rate, urinary protein excretion and renal structure were assessed 4 weeks later at 16 weeks post-surgery.

Results:

Enalapril-treated subtotal nephrectomy rats receiving control endothelial basal medium-2 injections experienced only partial renoprotection when compared to vehicle-treated subtotal nephrectomy rats. In contrast, conditioned medium infusion, when administered in addition to enalapril, attenuated the progression of renal dysfunction in subtotal nephrectomy rats, improving glomerular filtration rate and reducing proteinuria without affecting blood pressure.

Conclusions:

Early outgrowth cell-derived factors exert additive renoprotective effects on top of angiotensin-converting enzyme inhibitor therapy in experimental chronic kidney disease, providing the rationale for clinical trials of early outgrowth cell-based therapies for chronic kidney disease.

Repeated treatment with bone marrow cell secretory products maintains long-term renoprotection in experimental chronic kidney disease: a placebo-controlled trial

Background

Bone marrow-derived early outgrowth cells (EOCs) secrete soluble factors that exert potent renoprotective effects, such that infusion of their conditioned medium recapitulates the affects of the cells themselves.

Objectives

The objective of this study is to test whether the protective effect of conditioned medium infusion wanes with time and whether tachyphylaxis occurs with repeated administration.

Design

This is a placebo-controlled animal study.

Setting

The study was conducted at St. Michael’s Hospital, Toronto, Ontario, Canada.

Subjects

Fischer 344 (F344) rats were used in this study.

Measurements

The following were measured: (1) urinary protein:creatinine ratio, (2) glomerular filtration rate, (3) systolic blood pressure, (4) body weight, (5) glomerular endothelial cell density, and (6) glomerular and tubulointerstitial type IV collagen deposition.

Methods

Subtotally nephrectomized F344 rats, a model of progressive chronic kidney disease, were randomized 4 weeks post-surgery to receive thrice-weekly intravenous injections of concentrated EOC-conditioned medium (EOC CM) or unconditioned medium (UCM) over 2 weeks. Three animal groups were studied, according to whether they were administered conditioned medium: once (Initial Therapy Only group), twice (Repeat Therapy group), or not at all (No Therapy group).

Results

Following initial therapy, EOC CM-treated animals excreted less urinary protein, a marker of renal injury, than their UCM-treated counterparts. At 10 weeks post-subtotal nephrectomy, however, mean urinary protein excretion in conditioned medium-treated animals was fourfold greater than at the completion of the initial treatment course. At this time point, conditioned medium-treated animals were randomized to receive a second course of either conditioned medium (Repeat Therapy group) or unconditioned medium (Initial Therapy Only group). At study end (14 weeks post-subtotal nephrectomy), Repeat Therapy animals demonstrated higher glomerular filtration rate, less proteinuria, preserved renal microvasculature, and diminished fibrosis when compared with the No Therapy group. Initial Therapy Only animals exhibited an intermediate effect.

Limitations

Testing the effect of EOC-conditioned medium in a single model of chronic kidney disease (CKD) has limitations.

Conclusions

These findings suggest that early outgrowth cell-derived factors, while renoprotective, have a limited duration of action. Repeated administration of these factors, however, is able to extend the duration of efficacy and attenuate the progression of experimental chronic kidney disease.

Application of Modular Therapy for Renoprotection in Experimental Chronic Kidney Disease

Cell-based regenerative therapies offer a new alternative approach to the treatment of chronic disease. Specifically, studies by our laboratory and others have shown that a subpopulation of cells derived from the bone marrow, known as early outgrowth cells (EOCs), are able to attenuate the progression of chronic kidney disease (CKD). In this study we examined the efficacy of a tissue engineering system, in which EOCs were embedded into submillimeter-sized collagen cylinders. These small individual units are referred to as modules and together form a functional microtissue. Due to their resemblance to endothelial cells, late outgrowth cells (LOCs) were used to coat the module surface, hypothesizing that as such they would promote vascularization and enhance engraftment of the encapsulated EOCs. These coated modules were transplanted subcutaneously into the subtotally nephrectomized rat model of CKD. While coated module therapy significantly improved both renal structure and function, noncoated modules with embedded EOCs were unable to reproduce these salutary effects on the kidney. Nevertheless, in both treatments, the embedded EOCs quickly degraded the modular environment and were seen to migrate to the liver, spleen, and bone marrow as early as 6 days after transplantation. With the efflux of EOCs, and unexpectedly no evidence of vascularization, we hypothesized that the LOCs did not enhance EOC engraftment, but rather augmented the renoprotection provided by EOCs by secretion of their own soluble and potent antifibrotic factors. To the best of our knowledge, this is the first study to document an effective subcutaneous approach for renoprotection.

Early outgrowth cells release soluble endocrine antifibrotic factors that reduce progressive organ fibrosis

Adult bone marrow-derived cells can improve organ function in chronic disease models, ostensibly by the release of paracrine factors. It has, however, been difficult to reconcile this prevailing paradigm with the lack of cell retention within injured organs and their rapid migration to the reticuloendothelial system. Here, we provide evidence that the salutary antifibrotic effects of bone marrow-derived early outgrowth cells (EOCs) are more consistent with an endocrine mode of action, demonstrating not only the presence of antifibrotic factors in the plasma of EOC-treated rats but also that EOC conditioned medium (EOC-CM) potently attenuates both TGF-β- and angiotensin II-induced fibroblast collagen production in vitro. To examine the therapeutic relevance of these findings in vivo, 5/6 subtotally nephrectomized rats, a model of chronic kidney and heart failure characterized by progressive fibrosis of both organs, were randomized to receive i.v. injections of EOC-CM, unconditioned medium, or 10(6) EOCs. Rats that received unconditioned medium developed severe kidney injury with cardiac diastolic dysfunction. In comparison, EOC-CM-treated rats demonstrated substantially improved renal and cardiac function and structure, mimicking the changes found in EOC-treated animals. Mass spectrometric analysis of EOC-CM identified proteins that regulate cellular functions implicated in fibrosis. These results indicate that EOCs secrete soluble factor(s) with highly potent antifibrotic activity, that when injected intravenously replicate the salutary effects of the cells themselves. Together, these findings suggest that an endocrine mode of action may underlie the effectiveness of cell therapy in certain settings and portend the possibility for systemic delivery of cell-free therapy.

Allogeneic mesenchymal stem cell transplantation for lupus nephritis patients refractory to conventional therapy

Allogeneic mesenchymal stem cell transplantation (MSCT) has been shown to be clinically efficacious in the treatment of various autoimmune diseases. Here, we analyzed the role of allogeneic MSCT to induce renal remission in patients with active and refractory lupus nephritis (LN). This is an open-label and single-center clinical trial conducted from 2007 to 2010 in which 81 Chinese patients with active and refractory LN were enrolled. Allogeneic bone marrow- or umbilical cord-derived mesenchymal stem cells (MSCs) were administered intravenously at the dose of 1 million cells per kilogram of bodyweight. All patients were then monitored over the course of 12 months with periodic follow-up visits to evaluate renal remission, as well as possible adverse events. The primary outcome was complete renal remission (CR) and partial remission (PR) at each follow-up, as well as renal flares. The secondary outcome included renal activity score, total disease activity score, renal function, and serologic index. During the 12-month follow-up, the overall rate of survival was 95 % (77/81). Totally, 60.5 % (49/81) patients achieved renal remission during 12-month visit by MSCT. Eleven of 49 (22.4 %) patients experienced renal flare by the end of 12 months after a previous remission. Renal activity evaluated by British Isles Lupus Assessment Group (BILAG) scores significantly declined after MSCT (mean ± SD, from 4.48 ± 2.60 at baseline to 1.09 ± 0.83 at 12 months), in parallel with the obvious amelioration of renal function. Glomerular filtration rate (GFR) improved significantly 12 months after MSCT (mean ± SD, from 58.55 ± 19.16 to 69.51 ± 27.93 mL/min). Total disease activity evaluated by Systemic Lupus Erythematosus Disease Activity Index (SLEDAI) scores also decreased after treatment (mean ± SD, from 13.11 ± 4.20 at baseline to 5.48 ± 2.77 at 12 months). Additionally, the doses of concomitant prednisone and immunosuppressive drugs were tapered. No transplantation-related adverse event was observed. Allogeneic MSCT resulted in renal remission for active LN patients within 12-month visit, confirming its use as a potential therapy for refractory LN.

Therapeutic journeys: the hopeful travails of stem cell tourists

The recent growth of so-called stem cell tourism reflects the high optimism that currently surrounds stem cell science. Stem cell treatments for various conditions are increasingly advertised over the Internet as being available at hospitals and clinics around the world. However, most are clinically unproven. Despite numerous warnings from scientists about the dangers posed by such treatments, many individuals are evidently prepared to take the risk, sometimes on more than one occasion. This article explores the dynamics of hope that underpin stem cell tourism. Drawing on ideas from the sociology of hope, as applied to biomedicine, the article explores how hope is constructed and shapes actions in relation to stem cell treatments. Making reference to the findings from an Australian study of patients and carers who travelled overseas to receive stem cell treatments, it is argued that hope has an ambiguous significance in the context of deregulated health care. As we explain, this has implications for patients' and carers' treatment decisions and experiences. The findings are discussed in light of current responses to stem cell tourism.

Interactions of miR-323/miR-326/miR-329 and miR-130a/miR-155/miR-210 as prognostic indicators for clinical outcome of glioblastoma patients

Background

Thailand faces a significant burden in terms of treating and managing degenerative and chronic diseases. Moreover, incidences of rare diseases are rising. Many of these—such as diabetes, cancer, and inherited inborn metabolic diseases—have no definite treatments or cure. Meanwhile, advanced health biotechnology has been found, in principle, to be an effective solution for these health problems.

Methods

Qualitative approaches were employed to analyse the current situation and examine existing public policies related to advanced health biotechnologies in Thailand. The results of this analysis were then used to formulate policy recommendations.

Results

Our research revealed that the system in Thailand in relation to advanced health biotechnologies is fragmented, with multiple unaddressed gaps, underfunding of research and development (R&D), and a lack of incentives for the private sector. In addition, there are no clear definitions of advanced health biotechnologies, and coverage pathways are absent. Meanwhile, false advertising and misinformation are prevalent, with no responsible bodies to actively and effectively provide appropriate information and education (I&E). The establishment of a specialised institution to fill the gaps in this area is warranted.

Conclusion

The development and implementation of a comprehensive national strategic plan related to advanced health biotechnologies, greater investment in R&D and I&E for all stakeholders, collaboration among agencies, harmonisation of reimbursement across public health schemes, and provision of targeted I&E are specifically recommended.

From banking to international governance: fostering innovation in stem cell research

Stem cell banks are increasingly recognized as an essential resource of biological materials for both basic and translational stem cell research. By providing transnational access to quality controlled and ethically sourced stem cell lines, stem cell banks seek to foster international collaboration and innovation. However, given that national stem cell banks operate under different policy, regulatory and commercial frameworks, the transnational sharing of stem cell materials and data can be complicating. This paper will provide an overview of the most pressing challenges regarding the governance of stem cell banks, and the difficulties in designing regulatory and commercial frameworks that foster stem cell research. Moreover, the paper will shed light on the numerous international initiatives that have arisen to help harmonize and standardize stem cell banking and research processes to overcome such challenges.

The rise of cellular therapy

In 1938, the field of Transfusion Medicine began as the simpler entity - Blood Banking. It was a discipline that focused on collecting, processing, storing and distributing end stage blood cells, plasma and plasma fractions to patients. Over the years, the field progressed to include clinical patient services such as apheresis technology and with the development of stem cell transplantation as a standard of care, Cell Therapy. Now the discipline is also finding a niche in the area of Regenerative Medicine. The role played by Transfusion Medicine practitioners in Cell Therapy and Regenerative Medicine was predicated on many factors: (1) pre-existing, established protocols for therapeutic leukapheresis, (2) prior experience with mononuclear cell collection and processing, (3) long term familiarity with, and a clear understanding of, cGMP and cGLP guidelines, Federal regulations, and the voluntary standards established by various organizations, (4) close relationships with practitioners in clinical departments of medicine, pediatrics, oncology, surgery, and their subspecialty areas. While the initial Cell Therapy programs related primarily to hematopoietic stem cell transplantation, as Regenerative Medicine programs developed, transfusion specialists found it to be a related field that would also benefit from their input. Cell Therapy and Regenerative Medicine, now provide fertile soil for the seeds of Transfusion Medicine to grow. The once narrowly defined field of Blood Banking now encompasses involvement in major new Cellular Therapy/Regenerative Medicine research protocols related to treatment of patients with cancer as well as renal, hepatic and cardiac illnesses. This in turn provides opportunities for residents and fellows to consider robust careers in the field of Transfusion Medicine. In this manner we will move forward with one eye on the past and another on the promising future.