Glomerular lipidosis as a feature of renal-limited macrophage activation syndrome in a transplanted kidney: a case report.

BACKGROUND: Glomerular lipidosis is a rare histological feature presenting the extensive glomerular accumulation of lipids with or without histiocytic infiltration, which develops under various conditions. Among its various etiologies, macrophage activation syndrome (MAS) is a condition reported to be associated with histiocytic glomerular lipidosis. Here we describe the first case of glomerular lipidosis observed in a renal allograft that histologically mimicked histiocytic glomerulopathy owing to MAS. CASE PRESENTATION: A 42-year-old man underwent successful living-donor kidney transplantation. However, middle-grade proteinuria and increased serum triglyceride levels indicative of type V hyperlipidemia developed rapidly thereafter. An allograft biopsy performed 6 months after the transplantation showed extensive glomerular infiltration of CD68+ foam cells (histiocytes) intermingled with many CD3+ T-cells (predominantly CD8+ cells). Furthermore, frequent contact between glomerular T-cells and histiocytes, and the existence of activated CD8+ cells (CD8+, HLA-DR+ cells) were observed by double immunostaining. There was no clinicopathological data suggesting lipoprotein glomerulopathy or lecithin cholesterol acyltransferase deficiency, both of which are well-known causes of glomerular lipidosis. The histological findings were relatively similar to those of histiocytic glomerulopathy caused by MAS. As systemic manifestations of MAS, such as fever, pancytopenia, coagulation abnormalities, hyperferritinemia, increased liver enzyme levels, hepatosplenomegaly, and lymphadenopathy were minimal, this patient was clinicopathologically diagnosed as having renal-limited MAS. Although optimal treatment strategies for MAS in kidney transplant patients remains unclear, we strengthened lipid-lowering therapy using pemafibrate, without modifying the amount of immunosuppressants. Serum triglyceride levels were normalized with this treatment; however, the patient's extensive proteinuria and renal dysfunction did not improve. Biopsy analysis at 1 year after the transplantation demonstrated the disappearance of glomerular foamy changes, but the number of glomerular infiltrating cells remained similar. CONCLUSION: To our knowledge, this is the first reported case of glomerular lipidosis in a transplanted kidney. Increased interaction-activation of histiocytes (macrophages) and CD8+ T-cells, the key pathogenic feature of MAS, was observed in the glomeruli of this patient, who did not demonstrate overt systemic manifestations, suggesting a pathological condition of renal-limited MAS. The clinical effects of triglyceride-lowering therapy were limited, suggesting that hypertriglyceridemia was not the cause of but rather may be a consequence of renal-limited MAS.

Cytokine modulation in abdominal septic shock via the crucial role of IL-6 signaling in endothelial dysfunction.

Background: Early recovery from shock improves prognosis in septic shock patients. We determined whether cytokine modulation by Continuous Renal Replacement Therapy (CRRT) following acute care surgery resulted in stable hemodynamics in them. To investigate our hypothesis, we measured proinflammatory cytokines IL-6, IL-1ra and the coagulation cascade activator plasminogen activator inhibitor-1 (PAI-1) following CRRT with polymyxin B immobilized fiber (PMX-DHP) which has been utilized as an adjuvant treatment option for patients with severe septic shock. Methods: 66 septic shock patients requiring 2 h direct hemoperfusion therapy PMX-DHP were included. 36 patients of them also received continuous hemodiafiltration (CHDF) after performing PMX-DHP. Circulatory dynamics and levels of inflammatory mediators, namely IL-6, IL-1ra, and PAI-1 were assessed before, immediately after, and 24 h initiation of PMX-DHP. Results: Mean Arterial Pressure (MAP) rose intentionally by PMX-DHP just after enforcement 24 h later (p < 0.01). Levels of IL-6, IL-1ra, and PAI-1 significantly decreased after PMX-DHP (p < 0.05) and this trend was observed up to 24 h post initiation of PMX-DHP (p < 0.05). IL-6 modulation by PMX-DHP was enhanced with using CHDF and there was a significant correlation between IL-6 and MAP (p < 0.0001). In addition, levels of Il-6 and PAI-1 showed a significant correlation. Conclusion: Our data showed employing CRRT as cytokine modulators could be an additional therapeutic strategy to improve septic shock outcomes via the crucial role of IL-6 signaling in endothelial dysfunction.

Metabolomic Profiling of Plasma, Urine, and Saliva of Kidney Transplantation Recipients.

Kidney biopsy is commonly used to diagnose kidney transplant dysfunction after transplantation. Therefore, the development of minimally invasive and quantitative methods to evaluate kidney function in transplant recipients is necessary. Here, we used capillary electrophoresis-mass spectrometry to analyze the biofluids collected from transplant recipients with impaired (Group I, n = 31) and stable (Group S, n = 19) kidney function and from donors (Group D, n = 9). Metabolomics analyses identified and quantified 97 metabolites in plasma, 133 metabolites in urine, and 108 metabolites in saliva. Multivariate analyses revealed apparent differences in the metabolomic profiles of the three groups. In plasma samples, arginine biosynthesis and purine metabolism between the I and S Groups differed. In addition, considerable differences in metabolomic profiles were observed between samples collected from participants with T cell-mediated rejection (TCR), antibody-mediated rejection, and other kidney disorders (KD). The metabolomic profiles in the three types of biofluids showed different patterns between TCR and KD, wherein 3-indoxyl sulfate showed a significant increase in TCR consistently in both plasma and urine samples. These results suggest that each biofluid has different metabolite features to evaluate kidney function after transplantation and that 3-indoxyl sulfate could predict acute rejection.

Ultrafast Excited State Dynamics of Forward and Reverse trans-cis Photoisomerization of Red-Light-Absorbing Indigo Derivatives.

Femtosecond time-resolved transient absorption (TRTA) spectroscopy was carried out to investigate the ultrafast excited state dynamics of both trans → cis and trans ← cis photoisomerization of red-light-absorbing indigo derivatives. For N,N'-bis(tert-butyloxycarbonylmethyl)indigo (tBOMI), the excited state lifetime of the trans-form was measured to be 41 ps while that of the cis-form was as short as 730 fs in acetonitrile (Acn). The excited state lifetime of trans-N,N'-dimethylindigo (DMI) in Acn was also measured to be as short as 10 ps. These values are much shorter than those of the blue-light-absorbing trans-forms of indigo derivatives such as N,N'-diacetylindigo (DAI) and thioindigo (ThI). The chromophore of indigo is composed of two pairs of electron donor and acceptor substituents conjugated in the shape of a letter "H" (so-called "H-chromophore"), although DFT and TDDFT calculations suggest that the charge transfer (CT) character is not very significant. Nevertheless, when a weak CT within the H-chromophore is promoted, the absorption band shifts to longer wavelengths and the excited state lifetime shortens. For the photoisomerization of DAI and ThI, a relatively long excited state lifetime is required for the photoisomerization, while for tBOMI and DMI, a vibrationally hot ground state that overcomes the energy barrier in the ground state is produced by rapid nonradiative decay through conical intersection. In the case of cis-tBOMI, the repulsion between the two adjacent negatively charged carbonyl groups and the weakening of the central C═C double bond in the S1 state twist the molecule, shorten the excited state lifetime, and increase the quantum yield of the trans ← cis photoisomerization.

Individual Lymphocyte Sensitivity to Steroids as a Reliable Biomarker for Clinical Outcome after Steroid Withdrawal in Japanese Renal Transplantation.

Recently, steroid reduction/withdrawal regimens have been attempted to minimize the side effects of steroids in renal transplantation. However, some recipients have experienced an increase/resumption of steroid administrations and acute graft rejection (AR). Therefore, we investigated the relationship between the individual lymphocyte sensitivity to steroids and the clinical outcome after steroid reduction/withdrawal. We cultured peripheral blood mononuclear cells (PBMCs) isolated from 24 recipients with concanavalin A (Con A) in the presence of methylprednisolone (MPSL) or cortisol (COR) for four days, and the 50% of PBMC proliferation (IC50) values and the PBMC sensitivity to steroids were calculated. Regarding the experience of steroid increase/resumption and incidence of AR within one year of steroid reduction/withdrawal, the IC50 values of these drugs before transplantation in the clinical event group were significantly higher than those in the event-free group. The cumulative incidence of steroid increase/resumption and AR in the PBMC high-sensitivity groups to these drugs before transplantation were significantly lower than those in the low-sensitivity groups. These observations suggested that an individual's lymphocyte sensitivity to steroids could be a reliable biomarker to predict the clinical outcome after steroid reduction/withdrawal and to select the patients whose dose of steroids can be decreased and/or withdrawn after transplantation.

Pharmacodynamic Drug-Drug Interaction on Human Peripheral Blood Mononuclear Cells Between Everolimus and Tacrolimus at the Therapeutic Concentration Range in Renal Transplantation.

BACKGROUND Everolimus (EVL) plus tacrolimus (TAC) therapy is effective and safe in renal transplantation. However, the pharmacokinetic and pharmacodynamic information for EVL combined with TAC is limited. We investigated the pharmacodynamic drug-drug interaction between EVL and TAC at their therapeutic concentration range. MATERIAL AND METHODS Isolated peripheral blood mononuclear cells (PBMCs) from 22 healthy participants aged 22 to 24 years were cultured with concanavalin A (Con A) in the presence of EVL and/or TAC for 4 days, and the proliferation rate of the PBMCs was calculated. RESULTS TAC promoted the inhibitory efficacy of EVL against the mitogen-activated proliferation of PBMCs at the EVL therapeutic concentration range. When 0.175 ng/mL or more of TAC was combined with 30 ng/mL or more of EVL, the antagonistic effect of TAC on the inhibitory efficacy of EVL against the mitogen-activated proliferation of PBMCs was observed. Conversely, when 0.4 ng/mL TAC and 10 ng/mL or more of EVL were combined, the antagonistic effect of EVL on the inhibitory efficacy of TAC against the mitogen-activated proliferation of PBMCs was observed. CONCLUSIONS The pharmacodynamic synergistic efficacy of EVL and TAC in combination on mitogen-activated PBMCs was evident at the therapeutic concentration range, which is used in renal transplantation. However, these drugs antagonize each other to suppress the proliferation of activated PBMCs at concentrations higher than those clinically used.

Development of pure red cell aplasia by transmission and persistent infection of parvovirus B19 through a kidney allograft.

We report a case of pure red cell aplasia (PRCA) caused by parvovirus B19 (PVB19) infection, which was transmitted through a kidney allograft. The patient underwent a living-donor kidney transplant from his wife at the age of 60. Despite successful engraftment with a normal creatinine level, he developed severe anemia that required frequent blood transfusions 2 months after transplantation. Renal anemia was unlikely as his serum erythropoietin level was extremely high. A bone marrow aspiration test demonstrated the existence of large proerythroblasts. Although anti-PVB19 IgM antibody levels were not increased, polymerase chain reaction (PCR) detected PVB19 DNA in his serum. Thus, he was diagnosed as having PRCA induced by PVB19 infection. PCR analysis of total DNA isolated from 0-hour biopsy sections showed the existence of PVB19 DNA. Furthermore, PVB19 proteins was detected on renal tubules of 0-hour allograft by immunoperoxidase staining. Thus, transmission of PVB19 through the allograft was confirmed. A single course of intravenous immunoglobulin (IVIG) therapy resulted in substantial improvement; however, the effect was limited, and severe anemia relapsed after 5-6 months. Several courses of IVIG with adjustment of immunosuppressive drugs resulted in long-term remission. Our case demonstrates that donor-transmitted PVB19 infection should be suspected in kidney transplant recipients who develop refractory anemia during the early post-operative phase.

In situ formation of photoactive B-ring reduced chlorophyll isomer in photosynthetic protein LH2.

Natural chlorophylls have a D-ring reduced chlorin π-system; however, no naturally occurring photosynthetically active B-ring reduced chlorins have been reported. Here we report a B-ring reduced chlorin, 17,18-didehydro-bacteriochlorophyll (BChl) a, produced by in situ oxidation of B800 bacteriochlorophyll (BChl) a in a light-harvesting protein LH2 from a purple photosynthetic bacterium Phaeospirillum molischianum. The regioselective oxidation of the B-ring of B800 BChl a is rationalized by its molecular orientation in the protein matrix. The formation of 17,18-didehydro-BChl a produced no change in the local structures and circular arrangement of the LH2 protein. The B-ring reduced 17,18-didehydro-BChl a functions as an energy donor in the LH2 protein. The photoactive B-ring reduced Chl isomer in LH2 will be helpful for understanding the photofunction and evolution of photosynthetic cyclic tetrapyrrole pigments.

Reduction in circulating level of HMGB-1 following continuous renal replacement therapy in sepsis.

Early recovery from shock improves prognosis in patients with severe sepsis and septic shock. During this period, cytokine imbalances mediate the development of organ damage and mortality. In Japan, we have access to hemoperfusion using an immobilized polymyxin B fiber column for endotoxin removal (PMX-DHP) and continuous hemodiafiltration (CHDF) as artificial support for patients with septic shock, with the aim of improving hemodynamics and organ dysfunction caused by elevated inflammatory cytokines and mediators. In this Short communication, we discuss recent findings showing anti-inflammatory treatment following these continuous renal replacement therapies in sepsis.

Synergistic Effects of Calcineurin Inhibitors and Steroids on Steroid Sensitivity of Peripheral Blood Mononuclear Cells.

The steroid receptor (SR) complex contains FKBP51 and FKBP52, which bind to tacrolimus (TAC) and cyclophilin 40, which, in turn, bind to cyclosporine (CYA); these influence the intranuclear mobility of steroid-SR complexes. Pharmacodynamic interactions are thought to exist between steroids and calcineurin inhibitors (CNIs) on the SR complex. We examined the effect of CNIs on steroid sensitivity. Methylprednisolone (MPSL) sensitivity was estimated as the concentration inhibiting mitosis in 50% (IC50) of peripheral blood mononuclear cells and as the area under the MPSL concentration-proliferation suppressive rate curves (CPS-AUC) in 30 healthy subjects. MPSL sensitivity was compared between the additive group (AG) as the MPSL sensitivity that was a result of addition of the proliferation suppressive rate of CNIs to that of MPSL and the mixed culture group (MCG) as MPSL sensitivity of mixed culture with both MPSL and CNIs in identical patients. IC50 values of MPSL and cortisol sensitivity were examined before and 2 months after CNI administration in 23 renal transplant recipients. IC50 and CPS-AUC values of MPSL were lower in the MCG than in the AG with administration of TAC and CYA. The CPS-AUC ratio of MCG and AG was lower in the TAC group. IC50 values of MPSL and cortisol tended to be lower after administration of TAC and CYA, and a significant difference was observed in the IC50 of cortisol after TAC administration. Steroid sensitivity increased with both TAC and CYA. Furthermore, TAC had a greater effect on increasing sensitivity. Thus, concomitant administration of CNIs and steroids can increase steroid sensitivity.

Comparative study of the cellular pharmacodynamics of calcineurin inhibitors between patients with chronic renal failure awaiting renal transplantation and cirrhosis patients awaiting liver transplantation.

The in vitro response of peripheral blood mononuclear cells (PBMCs) to the suppressive effects of calcineurin inhibitors is known to correlate with the clinical efficacy of drugs used in renal transplantations. The present study was conducted to examine the differences of PBMC responses to calcineurin inhibitors between chronic renal failure (CRF) patients awaiting renal transplantation and cirrhosis patients awaiting liver transplantation. The study included 99 CRF patients awaiting renal transplantation and 27 cirrhosis patients awaiting liver transplantation. Twenty milliliters of venous blood was taken 1-7 days before transplantation. The in vitro drug concentrations giving 50% inhibition of PBMC blastogenesis stimulated with concanavalin A (IC(50)s) were calculated. The suppressive effects of tacrolimus against PBMC blastogenesis were more than 10-100 times stronger than those of cyclosporine. The median IC(50) value for cyclosporine against the CRF PBMCs was not significantly different from the median IC(50) value against the cirrhosis PBMCs. In contrast, tacrolimus sensitivity in cirrhosis PBMCs is approximately seven times higher than that in CRF PBMCs. The median IC(50) value for tacrolimus against cirrhosis PBMCs was significantly lower and therefore the effect was stronger in comparison to the CRF PBMCs (p < 0.001). These data suggest that the PBMCs of cirrhosis patients, in comparison to those of CRF patients, are highly sensitive to the suppressive effect of tacrolimus. However, PBMC sensitivity to cyclosporine was not significantly different between the CRF and cirrhosis patients. These observations raise the possibility that treatment with tacrolimus, rather than cyclosporine, may therefore be a better choice to reduce the risks of allograft rejection in liver transplantation.

Evidence of different pharmacokinetics including relationship among AUC, peak, and trough levels between cyclosporine and tacrolimus in renal transplant recipients using new pharmacokinetic parameter--why cyclosporine is monitored by C(2) level and tacrolimus by trough level--.

The clinical efficacy of calcineurin inhibitors administered to renal transplant patients is considered to be a strong function of the area under the concentration time curve (AUC). Interestingly, monitoring timings of blood concentrations for two similar calcineurin inhibitors, cyclosporine (CYA; Neoral) and tacrolimus (TAC; Prograf) are different. Namely, CYA blood concentration is usually monitored at 2 h after administration (C(2)) substituted for peak concentration (C(p)) and TAC at trough concentration (C(t)). In the literature, data describing such characteristics of CYA and TAC have been presented in the past. However, each of these patient groups had different backgrounds. We have attempted to examine the behavior of blood concentration curves simultaneously for both CYA and TAC by establishing controlled groups of renal transplant patients with similar clinical backgrounds. Furthermore, we have analyzed the correlation with C(p) and C(t) versus AUC implementing area under the trough level (AUTL), or area above the trough level (AATL) as new pharmacokinetic parameters, such that C(2) for CYA and C(t) for TAC have been verified using controlled clinical data. We have also found distinct differences in the pharmacokinetics between CYA and TAC with the relationships between AUC, C(p), and C(t).