Low birth weight is a risk factor for chronic kidney disease, whereas adult podocyte depletion is a key event in the pathogenesis of glomerulosclerosis. However, whether low birth weight due to poor maternal nutrition is associated with low podocyte endowment and glomerulosclerosis in later life is not known. Female Sprague-Dawley rats were fed a normal-protein diet (NPD; 20%) or low-protein diet (LPD; 8%), to induce low birth weight, from 3 wk before mating until postnatal day 21 (PN21), when kidneys from some male offspring were taken for quantitation of podocyte number and density in whole glomeruli using immunolabeling, tissue clearing, and confocal microscopy. The remaining offspring were fed a normal- or high-fat diet until 6 mo to induce catch-up growth and excessive weight gain, respectively. At PN21, podocyte number per glomerulus was 15% lower in low birth weight (LPD) than normal birth weight (NPD) offspring, with this deficit greater in outer glomeruli. Surprisingly, podocyte number in LPD offspring increased in outer glomeruli between PN21 and 6 mo, although an overall 9% podocyte deficit persisted. Postnatal fat feeding to LPD offspring did not alter podometric indexes or result in glomerular pathology at 6 mo, whereas fat feeding in NPD offspring was associated with far greater body and fat mass as well as podocyte loss, reduced podocyte density, albuminuria, and glomerulosclerosis. This is the first report that maternal diet can influence podocyte endowment. Our findings provide new insights into the impact of low birth weight, podocyte endowment, and postnatal weight on podometrics and kidney health in adulthood.NEW & NOTEWORTHY The present study shows, for the first time, that low birth weight as a result of maternal nutrition is associated with low podocyte endowment. However, a mild podocyte deficit at birth did not result in glomerular pathology in adulthood. In contrast, postnatal podocyte loss in combination with excessive body weight led to albuminuria and glomerulosclerosis. Taken together, these findings provide new insights into the associations between birth weight, podocyte indexes, postnatal weight, and glomerular pathology.

TRADD is an adaptor for TNFR1-induced apoptosis and NFκB activation. However, TRADD-deficient mice undergo normal development and contain normal lymphoid populations, which contrasts with an embryonic defect in mice lacking FADD, the shared adaptor mediating apoptosis. Recent studies indicate FADD suppresses embryonic necroptosis mediated by RIPK1. TRADD was suggested to also mediate necroptosis. Here we report that targeting TRADD fails to rescue Fadd −/− embryos from necroptosis, and ablation of TRADD rescues Ripk1 −/− mice from perinatal lethality when RIPK3-mediated necroptosis is disabled. The resulting Ripk1 −/− Ripk3 −/− Tradd −/− mice survive until early adulthood, but die thereafter. A single allele of Tradd is optimal for survival of Ripk1 −/− Ripk3 −/− Tradd +/− mice. We show that TRADD plays a more dominating role in NFκB-signaling than RIPK1. While RIPK1 protects thymocytes from TNFα-induced apoptosis, TRADD promotes this process. The data demonstrate that TRADD is critical in perinatal and adult mice lacking RIPK1 and RIPK3, which has not been appreciated in prior studies.

RIPK1 is originally identified as a protein associated with Fas and TNFR1, which can trigger apoptosis. However, initial studies indicated that RIPK1 is dispensable for apoptotic signaling. Instead, cells lacking RIPK1 are defective in TNFR1-induced activation of NF-kB, a critical player involved in pro-survival signaling. Recent studies indicate that a certain form of necrosis-like death, necroptosis, requires RIPK1. In contrast, the Fas-associated death domain (FADD) protein appears to play an obligatory role in apoptosis induced by Fas and TNFR1. Fadd−/− mice die in utero due to RIPK1 mediated necroptosis. More recently, studies including ours demonstrated that only when both FADD and RIPK3 were deleted will Ripk1−/− mice survive to adulthood. This result indicates perinatal lethality in Ripk1−/− mice is due to not only FADD-mediated apoptosis but also RIPK3-dependent necrosis. Interestingly, we found that in adult T cells RIPK1 only suppresses apoptosis. To facilitate the dissection of the multiple functions of RIPK1, we performed in vivo gene editing using the CRISPR/Cas9 technology. This allows selective interruption of one functional domain/motif of RIPK1. Using these novel mouse models, our data reveals a previously unappreciated function for RIPK1 in promoting apoptosis.

RIPK1 has emerged as a key effector in programmed necrosis or necroptosis. This function of RIPK1 is mediated by its protein serine/threonine kinase activity and through the downstream kinase RIPK3. Deletion of RIPK1 prevents embryonic lethality in mice lacking FADD, a signaling adaptor protein required for activation of Caspase 8 in extrinsic apoptotic pathways. This indicates that FADD-mediated apoptosis inhibits RIPK1-dependent necroptosis to ensure successful embryogenesis. However, the molecular mechanism for this critical regulation remains unclear. In the current study, a novel mouse model has been generated, by disrupting a potential caspase cleavage site at aspartic residue (D)324 in RIPK1. Interestingly, replacing D324 with alanine (A) in RIPK1 results in midgestation lethality, similar to the embryonic defect in FADD −/− mice but in stark contrast to the normal embryogenesis of RIPK1 −/− null mutant mice. Surprisingly, disrupting the downstream RIPK3 alone is insufficient to rescue RIPK1 D324A/D324A mice from embryonic lethality, unless FADD is deleted simultaneously. Further analyses reveal a paradoxical role for RIPK1 in promoting caspase activation and apoptosis in embryos, a novel mechanism previously unappreciated.

The occurrence of a spontaneous nephropathy with intranuclear inclusions in laboratory mice has puzzled pathologists for over 4 decades, because its etiology remains elusive. The condition is more severe in immunodeficient animals, suggesting an infectious cause. Using metagenomics, we identify the causative agent as an atypical virus, termed "mouse kidney parvovirus" (MKPV), belonging to a divergent genus of Parvoviridae. MKPV was identified in animal facilities in Australia and North America, is transmitted via a fecal-oral or urinary-oral route, and is controlled by the adaptive immune system. Detailed analysis of the clinical course and histopathological features demonstrated a stepwise progression of pathology ranging from sporadic tubular inclusions to tubular degeneration and interstitial fibrosis and culminating in renal failure. In summary, we identify a widely distributed pathogen in laboratory mice and estab- lish MKPV-induced nephropathy as a new tool for elucidating mechanisms of tubulointerstitial fibrosis that shares molecular features with chronic kidney disease in humans.

infants at risk of neurodevelopmental disability in order to intervene early and improve outcomes. Neonates who undergo major surgery are known to be at risk of poor neurodevelopment, however there is a paucity of data on the use of the General Movements Assessment GMA with this population, despite strong evidence for use of the GMA in other high risk groups. Methods: 278 infants who had undergone cardiac surgery (n=149, 54%), non-cardiac surgery (n= 123, 44%), or both surgeries (n=6, 2%) were assessed using the GMA at a mean age of 12 weeks (SD 1.6 weeks). Videos were independently rated by three clinicians, two blinded to clinical details. Multidisciplinary follow-up was at one year of age. Results: There were twenty-five infants with absent fidgety movements (9%), and fifteen of these demonstrated clinical signs of CP at one year of age. Another six had developmental delay, including three with severe delay. There was a significant difference in the developmental outcomes of these infants compared to those with normal fidgety movements, across all subtests of the Bayley Scales of Infant and Toddler Development (p<0.05). Of the 248 (89%) infants with normal fidgety movements, none had a diagnosis of CP at 12 months of age. Conclusions: The GMA has predictive value for CP in this unique population. It is a valid complementary assessment tool that should be incorporated into the multidisciplinary follow-up for infants following surgery in order to facilitate referral into specialised early intervention services.

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Daxx was originally isolated as a Fas-binding protein. However, the in vivo function of Daxx in Fas-induced apoptosis has remained enigmatic. Fas plays an important role in homeostasis in the immune system. Fas gene mutations lead to autoimmune-lymphoproliferation (lpr) diseases characterized by hyperplasia of secondary lymphoid organs. It is well established that the FADD adaptor binds to Fas, and recruits/activates caspase 8. However, additional proteins including Daxx have also been indicated to associate with Fas. It was proposed that Daxx mediates a parallel apoptotic pathway that is independent of FADD and caspase 8, but signals through ASK1-mediated apoptotic pathway. However, because the deletion of Daxx leads to embryonic lethality, the in vivo function of Daxx has not been properly analyzed. In the current study, analysis was performed using a conditional mutant mouse in which Daxx was deleted specifically in T cells. The data show that Daxx(-/-) T cells were able to undergo normal Fas-induced apoptosis. While containing normal thymocyte populations, the T cell-specific Daxx(-/-) mice have a reduced peripheral T cell pool. Importantly, Daxx-deficient T cells displayed increased death responses upon activation through TCR stimulation. These results unequivocally demonstrated that Daxx does not mediate Fas-induced apoptosis, but rather that it plays a critical role in survival responses in primary mature T cells.

showed ductal structures of atypical tumour cells that led to the diagnosis of invasive ductal carcinoma. In our patient, the brown areas and globules were caused by melanin in the epidermal tumour nests, and the blue-grey structures and bluish-white globules were interstitial melanophages and melanin deposition in the dermal tumour nests. The typical dermoscopic findings of bluegrey globules in basal cell carcinoma also result from interstitial melanophages and melanin deposition in the dermal tumour nests. The lack of an atypical pigment network indicates a non-melanocytic lesion, which helps to differentiate pigmented invasive ductal carcinoma from melanocytic tumours such as melanoma. Pigmented mammary Paget disease can also present as a pigmented skin lesion, mimicking melanoma clinically, dermoscopically, and histopathologically. Some dermoscopic findings such as diffuse brown pigmentation, blue-grey structures, and black dots simulate melanoma. Our case of pigmented invasive ductal carcinoma showed more irregular structures and colour variation, with larger, distinct globules compared with pigmented mammary Paget disease. In cases of pigmented mammary Paget disease, tumour cells spread horizontally within the epidermis, increasing melanin production by melanocytes in the epidermal lesion. In comparison, in pigmented invasive ductal carcinoma, tumour cells derived from ductal epithelium migrate upward vertically and form nests in the dermis and epidermis. A single case is insufficient to establish pathophysiology and the dermoscopic pattern. However, the disturbance of the basal layer could cause melanocyte migration into tumour nests and transfer melanin to tumour cells, suggesting that the dermoscopic findings of pigmented invasive ductal carcinoma include large brown globules and bluish-white globules arranged randomly, similar to basal cell carcinoma. Hiroto Horikawa, Noriko Umegaki-Arao, Takeru Funakoshi, Masayuki Amagai and Masaru Tanaka Department of Dermatology, Keio University School of Medicine, and Department of Dermatology, Tokyo Women’s Medical University Medical Centre East, Tokyo, Japan

RIP1 was originally identified as a protein associated with Fas and TNFR1, which can trigger apoptosis. However, initial studies indicated that RIP1 is dispensable for apoptotic signaling. Instead, cells lacking RIP1 are defective in TNFR1-induced activation of NF-kB, a critical player involved in pro-survival signaling. Recent studies indicate that a certain form of necrosis-like death, necroptosis, requires RIP1. In contrast, the Fas-associated death domain (FADD) protein appears to play an obligatory role in apoptosis induced by Fas and TNFR1. However, the embryonic lethality phenotype of fadd−/− mice had remained a long-standing enigma, until analysis was performed to induce simultaneous deletion of both FADD and RIP1. The resulting fadd−/−rip1−/− double mutant mice displayed normal embryogenesis, indicating that fadd−/− embryos die of RIP1-dependent necroptosis. On the other hand, absence of RIP1 blocks postnatal development. Most recently, studies including ours demonstrated that only when both FADD and RIP3 were deleted will rip1−/− mice survive to adulthood. This result indicates perinatal lethality in RIP1-deficient mice is due to not only FADD-mediated apoptosis but also RIP3-dependent necrosis. Interestingly, we found that lack of RIP1 greatly diminished lymphoaccumulation disease in fadd−/−rip3−/− mice. To investigate RIP1 functions in adult immune cells, we performed conditional deletion of RIP1 in lineage committed lymphoid cells. Viable hypomorphic mutant mice with selective loss of function were employed to delineate the complex signaling pathways mediated by RIP1 in vivo. The results revealed a novel mechanism in the adult lymphoid system, which is distinct from the role of RIP1 in neonatal cells.

Indoleamine 2,3-dioxygenase (IDO) is a heme-containing oxidoreductase that catalyzes the initial and rate-limiting step in the breakdown of non-dietary tryptophan. The biology and immunomodulatory role for IDO is discussed in this review with a focus on its interaction with immune cells and its potential therapeutic target in the clinic. IDO has been revealed to be a central regulator of immune responses in a broad variety of physiological and pathological settings, mostly serving as a multifaceted negative feedback mechanism, to self-regulate immune responses. IDO is considered a therapeutic target in cancer and the use of IDO inhibitors as single agent or in combination with other treatment modalities are under active investigation.

The death receptor, Fas, triggers apoptotic death and is essential for maintaining homeostasis in the peripheral lymphoid organs. RIP1 was originally cloned when searching for Fas-binding proteins and was later shown to associate also with the signaling complex of TNFR1. Although Fas exclusively induces apoptosis, TNFR1 primarily activates the pro-survival/pro-inflammatory NF-κB pathway. Mutations in Fas lead to lymphoproliferative (lpr) diseases, and deletion of TNFR1 results in defective innate immune responses. However, the function of RIP1 in the adult lymphoid system has not been well understood, primarily owing to perinatal lethality in mice lacking the entire RIP1 protein in germ cells. This current study investigated the requirement for RIP1 in the T lineage using viable RIP1 mutant mice containing a conditional and kinase-dead RIP1 allele. Disabling the kinase activity of RIP1 had no obvious impact on the T-cell compartment. However, T-cell-specific deletion of RIP1 led to a severe T-lymphopenic condition, owing to a dramatically reduced mature T-cell pool in the periphery. Interestingly, the immature T-cell compartment in the thymus appeared intact. Further analysis showed that mature RIP1−/− T cells were severely defective in antigen receptor-induced proliferative responses. Moreover, the RIP1−/− T cells displayed greatly increased death and contained elevated caspase activities, an indication of apoptosis. In total, these results revealed a novel, kinase-independent function of RIP1, which is essential for not only promoting TCR-induced proliferative responses but also in blocking apoptosis in mature T cells.

RIP1 is an adaptor kinase originally identified as being able to associate with TNFR1 and Fas, and is later shown to be involved in signaling induced by TLRs. Major signaling pathways regulated by RIP1 include necroptosis, apoptosis, and pro-survival/inflammation NF-κB activation. Previous studies show that RIP1 deficiency has no effect on mouse embryogenesis, but blocks postnatal development. This phenotype could not readily be explained, since mice lacking TNFR1, Fas, or TLRs show no apparent developmental defect. Certain types of RIP1-deficient cells are hypersensitive to TNF-induced apoptosis. However, in our previous study, deletion of the apoptotic adaptor protein, FADD, provides marginal improvement of postnatal development of rip1 (-/-) mice. Remarkably, the current data shows that haploid insufficiency of RIP3, a known mediator of necroptosis, allowed survival of rip1 (-/-) fadd (-/-) mice beyond weaning age, although the resulting rip1(-/-)fadd(-/-) rip3(+/-) mice were significant smaller in size and weight. Moreover, complete absence of RIP3 further improved postnatal development of the resulting rip1 (-/-) fadd (-/-) rip3 (-/-) mice, which display normal size and weight. In such triple knockout (TKO) mice, lymphocytes underwent normal development, but progressively accumulated as mice age. This lymphoproliferative (lpr) disease in TKO mice is, however, less severe than that of fadd(-/-)rip3 (-/-) double knockout mice. In total, the data show that the postnatal developmental defect in rip1 (-/-) mice is due in part to FADD-mediated apoptosis as well as RIP3-dependent necroptosis. Moreover, the function of RIP1 contributes to development of lpr diseases.

Natural killer (NK) cells have long been hypothesized to play a central role in the development of new immunotherapies to combat a variety of cancers due to their intrinsic ability to lyse tumor cells. For the past several decades, various isolation and expansion methods have been developed to harness the full antitumor potential of NK cells. These protocols have varied greatly between laboratories and several have been optimized for large-scale clinical use despite associated complexity and high cost. Here, we present a simple method of “adherent” enrichment and expansion of NK cells, developed using both healthy donors' and cancer patients' peripheral blood mononuclear cells (PBMCs), and compare its effectiveness with various published protocols to highlight the pros and cons of their use in adoptive cell therapy. By building upon the concepts and data presented, future research can be adapted to provide simple, cost-effective, reproducible, and translatable procedures for personalized treatment with NK cells.

BACKGROUND:Acute kidney injury due to glomerular bleeding has been described with IgA nephropathy and supratherapeutic warfarin anticoagulation. There is usually demonstrable tubular obstruction by erythrocyte casts associated with acute tubular injury. Although severe thrombocytopaenia increases the risk of bleeding, most cases of haematuria have been ascribed to non-glomerular or urological bleeding without a direct link to acute kidney injury. We describe a patient with acute kidney injury due to glomerular bleeding and tubular injury related to severe thrombocytopaenia, who was subsequently found to have thin basement membrane disease.CASE PRESENTATION:A 56 year old man presented with macroscopic haematuria, acute kidney injury and a platelet count of 35 × 10(9)/L, in the absence of anticoagulation. Urinalysis demonstrated an active urinary sediment. His kidney biopsy demonstrated extensive intraluminal erythrocyte casts associated with acute tubular injury, along with haemosiderin deposition suggestive of recurrent glomerular bleeding. There was no histological evidence of glomerular pathology but electron microscopy analysis demonstrated thin basement membrane disease and effacement of podocyte foot processes. During long term follow-up, thrombocytopaenia and intermittent haematuria persisted. At 9 months, the patient progressed to Stage 5 chronic kidney disease with the development of gross renal atrophy.CONCLUSION:Recurrent macroscopic haematuria may be a risk factor for progressive renal injury in patients with thin basement membrane. The mechanism may be due to recurrent acute kidney injury from glomerular bleeding leading to repeated tubular damage. In the absence of anticoagulation, severe thrombocytopaenia may be a risk factor for heavy glomerular bleeding and acute kidney injury in these patients.

Australia's Indigenous people have high rates of chronic kidney disease and kidney failure. To define renal disease among these people, we reviewed 643 renal biopsies on Indigenous people across Australia, and compared them with 249 biopsies of non-Indigenous patients. The intent was to reach a consensus on pathological findings and terminology, quantify glomerular size, and establish and compare regional biopsy profiles. The relative population-adjusted biopsy frequencies were 16.9, 6.6, and 1, respectively, for Aboriginal people living remotely/very remotely, for Torres Strait Islander people, and for non-remote-living Aboriginal people. Indigenous people more often had heavy proteinuria and renal failure at biopsy. No single condition defined the Indigenous biopsies and, where biopsy rates were high, all common conditions were in absolute excess. Indigenous people were more often diabetic than non-Indigenous people, but diabetic changes were still present in fewer than half their biopsies. Their biopsies also had higher rates of segmental sclerosis, post-infectious glomerulonephritis, and mixed morphologies. Among the great excess of biopsies in remote/very remote Aborigines, females predominated, with younger age at biopsy and larger mean glomerular volumes. Glomerulomegaly characterized biopsies with mesangiopathic changes only, with IgA deposition, or with diabetic change, and with focal segmental glomerulosclerosis (FSGS). This review reveals great variations in biopsy rates and findings among Indigenous Australians, and findings refute the prevailing dogma that most indigenous renal disease is due to diabetes. Glomerulomegaly in remote/very remote Aboriginal people is probably due to nephron deficiency, in part related to low birth weight, and probably contributes to the increased susceptibility to kidney disease and the predisposition to FSGS.

OBJECTIVE To determine the efficacy of imiquimod cream, 5%, in the treatment of lentigo maligna (LM). DESIGN Open-label before-and-after interventional study. SETTING A multidisciplinary melanoma clinic at a major tertiary hospital. PATIENTS Forty-three patients with biopsy-proven LM of greater than 5 mm in diameter completed this study. INTERVENTIONS Imiquimod cream, 5%, was applied to the lesion 5 days a week for 12 weeks. The original lesion was excised with a 5-mm margin. MAIN OUTCOME MEASURES The primary outcome was histopathologic evidence of LM in the excision specimen assessed independently by 2 of 3 dermatopathologists. Visible inflammation during treatment and macroscopic clearance were recorded. RESULTS When 5 of the 43 patients with discordant histopathologic assessment of the excision specimen were excluded, 20 of 38 patients (53% [95% confidence interval, 36%-69%]) demonstrated histopathologic clearance of LM after imiquimod treatment. Visible inflammation was significantly associated with histopathologic clearance (P = .04), but the positive predictive value was low (62%). Macroscopic clearance showed some association with histopathologic clearance (P = .11). Dermatopathologist concordance for all 43 specimens was substantial (κ = 0.77; 95% confidence interval, 0.57-0.96). CONCLUSIONS Imiquimod cream, 5%, has limited efficacy in the treatment of LM when determined by histopathologic assessment of the entire treated area. The clinical signs of visible inflammation during treatment and apparent lesion clearance cannot be relied on to assess efficacy.

A 28-year-old Costa Rican woman presented with a 6-year history of an asymptomatic progressive localized livedo racemosa on her limbs. Histological examination revealed a lymphocytic vasculitis targeting the arterioles in the deep dermis. In addition, a distinct hyalinised fibrin ring was noted at the periphery of the vessel lumen. These findings were consistent with the recently described entity known as lymphocytic thrombophilic arteritis. An extensive array of investigations did not show any underlying systemic disease, and the patient has remained in good health without treatment.