Diastolic Dysfunction as a Positive Predictor of Recurrent Vascular Events in Patients With Noncardioembolic Stroke.

BACKGROUND: This study aimed to assess the effects of left ventricular diastolic dysfunction (LVDD) on vascular outcomes among patients with stroke of noncardioembolic origins. METHODS: This prospective observational study enrolled 563 patients with noncardioembolic stroke (mean age, 67.9 years; 66.7% men and 33.3% women individuals) registered in the Tokyo Women's Medical University Stroke Registry between 2013 and 2020. Then, patients were divided into the LVDD and non-LVDD groups. The primary outcome was a composite of major adverse cardiovascular events, including nonfatal stroke, nonfatal acute coronary syndrome, and vascular death 1 year after stroke onset. The effect of LVDD on vascular events was assessed using multivariable Cox regression analyses. RESULTS: A total of 130 (23.1%) patients had any grade of LVDD, and patients with LVDD had a higher risk of major adverse cardiovascular event at 1 year than those without LVDD (annual rate, 20.9% versus 10.8%; log-rank P=0.001). The multivariable Cox proportional hazards regression model demonstrated that the presence of LVDD was independently associated with the major adverse cardiovascular event risk (hazard ratio, 1.79 [95% CI, 1.02-3.12]; P=0.019). Furthermore, the LVDD grade was proportional to the risk of major adverse cardiovascular events and recurrent stroke. CONCLUSIONS: LVDD may be associated with further vascular events after a noncardioembolic stroke, suggesting the importance of LVDD evaluations in risk stratification and secondary prevention in patients with noncardioembolic stroke. REGISTRATION: URL: https://upload.umin.ac.jp; Unique identifier: UMIN000031913.

AIM/CD5L ameliorates autoimmune arthritis by promoting removal of inflammatory DAMPs at the lesions.

The hallmark of autoimmune arthritis is the preceding autoantibody production and the following synovial inflammation with hyperplasia and tissue destruction of the joints. The joint inflammation is mediated not only by effector lymphocytes and auto-antibodies but also chronic activation of innate immunity, particularly promoted by the danger-associated molecular patterns (DAMPs). Here we show that apoptosis inhibitor of macrophage (AIM, also called CD5L) protein regulates arthritis by promoting removal of lesional DAMPs both physiologically and therapeutically. When the autoimmune arthritis was promoted by injecting a cocktail of anti-collagen antibodies without type-II collagen immunization, AIM-deficient (AIM-/-) mice exhibited more exacerbated and sustained swelling at multiple joints with greater synovial hyperplasia and bone erosion than wild-type mice. Administration of recombinant AIM (rAIM) reduced S100A8/9, a major DAMP known to be involved in arthritis progression, and decreased various inflammatory cytokines at the lesions in antibody-injected AIM-/- mice, leading to marked prevention of arthritis symptoms. In human rheumatoid arthritis (RA) patients, AIM was more activated via dissociating from IgM-pentamer in response to DAMPs-mediated inflammation both in serum and synovial fluid than in healthy individuals or non-autoimmune osteoarthritis patients, suggesting a disease-regulatory potency of AIM also in human RA patients. Thus, our study implied a therapeutic availability of rAIM to prevent arthritis symptoms targeting DAMPs.

Association of circulating CD34+ cells level and prognosis after ischemic stroke.

BACKGROUND: CD34 is a transmembrane phosphoglycoprotein and a marker of hematopoietic and nonhematopoietic stem/progenitor cells. In experimental studies, CD34+ cells are rich sources of endothelial progenitor cells and can promote neovascularization and endothelial repair. The potential role of CD34+ cells in stroke patients remains unclear. AIMS: We aimed to assess the prognostic effect of circulating CD34+ cell levels on the risk of vascular events and functional prognosis in stroke patients. PATIENTS AND METHODS: In this prospective observational study, patients with ischemic stroke were consecutively enrolled within 1 week of onset and followed up for 1 year. Patients were divided into three groups according to tertiles of the level of circulating CD34+ cells (Tertile 1, <0.51/µL; Tertile 2, 0.51-0.96/µL; and Tertile 3, >0.96/µL). The primary outcome was a composite of major adverse cardiovascular events (MACEs), including nonfatal stroke, nonfatal acute coronary syndrome, major peripheral artery disease, and vascular death. The secondary outcomes included the modified Rankin scale (mRS) scores. RESULTS: A total of 524 patients (mean age, 71.3 years; male, 60.1%) were included. High CD34+ cell levels were associated with younger age (p < 0.001) and low National Institutes of Health Stroke Scale scores at admission (p = 0.010). No significant differences were found in the risk of MACEs among the three groups (annual rates: 15.0%, 13.4%, and 12.6% in Tertiles 1, 2, and 3, respectively; log-rank p = 0.70). However, there were significant differences in the mRS scores at 3 months (median (interquartile range); 2 (1-4), 1 (1-3), and 1 (0-2) in Tertiles 1, 2, and 3, respectively; p = 0.010) and 1 year (3 (1-4), 2 (1-4), and 1 (0-3); p < 0.001) among these groups. After multivariable adjustments, a higher CD34+ cell level was independently associated with good functional outcomes (mRS score of 0-2) at 3 months (adjusted odds ratio (OR), 1.43; 95% confidence interval (CI), 1.01-2.05) and 1 year (adjusted OR, 1.53; 95% CI, 1.09-2.16). CONCLUSION: Although no correlations were found between circulating CD34+ cell levels and vascular event risk, elevated CD34+ cell levels were associated with favorable functional recovery in stroke patients. DATA ACCESS STATEMENT: Data supporting the findings of this study are available from the corresponding author on reasonable request. CLINICAL TRIAL REGISTRATION: The TWMU Stroke Registry is registered at https://upload.umin.ac.jp as UMIN000031913.

Apoptosis inhibitor of macrophages/CD5L enhances phagocytosis in the trabecular meshwork cells and regulates ocular hypertension.

The trabecular meshwork (TM) cells of the eye are important for controlling intraocular pressure (IOP) and regulating outflow resistance in the aqueous humor. TM cells can remove particles and cellular debris by phagocytosis, decreasing both outflow resistance and IOP. However, the underlying mechanisms remain unclear. Here, we investigate whether apoptosis inhibitor of macrophages (AIM), which mediates the removal of dead cells and debris in renal tubular epithelial cells, regulates the phagocytic capacity of TM cells. In vitro experiments revealed that CD36, the main receptor for AIM, colocalized with AIM in human TM cells; additionally, phagocytosis was stimulated when AIM was provided. Furthermore, in a mouse model with transient IOP elevation induced by laser iridotomy (LI), removal of accumulated iris pigment epithelial cells or debris in the TM and recovery of IOP to baseline levels were delayed in AIM-/- mice, compared with control mice. However, treatment with AIM eyedrops rescued AIM-/- mice from the elevated IOP after LI. Since AIM is a protein known to inhibit macrophage apoptosis, we additionally verified its involvement in macrophage removal of cellular debris and IOP. There were no statistically significant differences in the number of macrophages between control mice and AIM-/- mice in the TM. Additionally, we confirmed the rescue effect of the rAIM eyedrops after macrophages had been removed by clodronate liposomes. Therefore, AIM plays an important role in regulating the phagocytic capacity of TM cells, thereby affecting outflow resistance. Our results suggest that drugs targeting the phagocytic capacity of TM cells via the AIM-CD36 pathway may be used to treat glaucoma.

Apoptosis inhibitor of macrophage (AIM)/CD5L is involved in the pathogenesis of COPD.

BACKGROUND: Alveolar macrophages (AMs) and AM-produced matrix metalloprotease (MMP)-12 are known to play critical roles in the pathogenesis of chronic obstructive pulmonary disease (COPD). The apoptosis inhibitor of the macrophages (AIM)/CD5 molecule-like (CD5L) is a multifunctional protein secreted by the macrophages that mainly exists in the blood in a combined form with the immunoglobulin (Ig)M pentamer. Although AIM has both facilitative and suppressive roles in various diseases, its role in COPD remains unclear. METHODS: We investigated the role of AIM in COPD pathogenesis using porcine pancreas elastase (PPE)-induced and cigarette smoke-induced emphysema mouse models and an in vitro model using AMs. We also analyzed the differences in the blood AIM/IgM ratio among nonsmokers, healthy smokers, and patients with COPD and investigated the association between the blood AIM/IgM ratio and COPD exacerbations and mortality in patients with COPD. RESULTS: Emphysema formation, inflammation, and cell death in the lungs were attenuated in AIM-/- mice compared with wild-type (WT) mice in both PPE- and cigarette smoke-induced emphysema models. The PPE-induced increase in MMP-12 was attenuated in AIM-/- mice at both the mRNA and protein levels. According to in vitro experiments using AMs stimulated with cigarette smoke extract, the MMP-12 level was decreased in AIM-/- mice compared with WT mice. This decrease was reversed by the addition of recombinant AIM. Furthermore, an analysis of clinical samples showed that patients with COPD had a higher blood AIM/IgM ratio than healthy smokers. Additionally, the blood AIM/IgM ratio was positively associated with disease severity in patients with COPD. A higher AIM/IgM ratio was also associated with a shorter time to the first COPD exacerbation and higher all-cause and respiratory mortality. CONCLUSIONS: AIM facilitates the development of COPD by upregulating MMP-12. Additionally, a higher blood AIM/IgM ratio was associated with poor prognosis in patients with COPD. TRIAL REGISTRATION: This clinical study, which included nonsmokers, healthy smokers, and smokers with COPD, was approved by the Ethics Committee of the Hokkaido University Hospital (012-0075, date of registration: September 5, 2012). The Hokkaido COPD cohort study was approved by the Ethics Committee of the Hokkaido University School of Medicine (med02-001, date of registration: December 25, 2002).

Differences and similarities in cytokine profiles of macrophage activation syndrome in systemic lupus erythematosus and adult-onset Still's disease.

To clarify the differences and similarities in the cytokine profiles of macrophage activating syndrome (MAS) between systemic lupus erythematosus (SLE) and adult-onset Still's disease (AOSD). The study participants included 9 patients with MAS-SLE, 22 with non-MAS-SLE, 9 with MAS-AOSD, and 13 with non-MAS-AOSD. Serum cytokine levels were measured using a multiplex bead assay. Cytokine levels were compared between patients with SLE and AOSD with/without MAS. Moreover, cytokine patterns were examined using principal component analysis (PCA) and cluster analysis. IL-6, IL-8, IL-18, and TNF-α levels were elevated in patients with SLE and AOSD. IFN-α levels were elevated in SLE, whereas IL-1ß and IL-18 levels were elevated in AOSD. In SLE, IFN-α and IL-10 levels were higher in MAS than in non-MAS and controls. PCA revealed distinctive cytokine patterns in SLE and AOSD, SLE with IFN-α and IP-10, AOSD with IL-1ß, IL-6, and IL-18, and enhanced cytokine production in MAS. PCA and cluster analysis showed no differences in cytokine patterns between the MAS and non-MAS groups. However, serum ferritin levels were correlated with IFN-α levels in SLE. Cytokine profiles differed between SLE and AOSD but not between MAS and non-MAS. MAS is induced by the enhancement of underlying cytokine abnormalities rather than by MAS-specific cytokine profiles. Type I IFN may be involved in MAS development in patients with SLE.

Hyperhomocysteinemia Increases Vascular Risk in Stroke Patients with Chronic Kidney Disease.

AIMS: We aimed to assess the prognostic impact of hyperhomocysteinemia (HHcy) on the recurrent vascular event risk in stroke patients with or without chronic kidney disease (CKD). METHODS: In this prospective observational study, 621 patients (mean age, 69.5 years; male, 62.2%) with ischemic stroke or transient ischemic attack were consecutively enrolled within 1 week of onset and followed-up for 1 year. HHcy was defined as elevated levels of fasting total homocysteine ＞15 µmol/L. CKD was defined as an estimated glomerular filtration rate of ＜60 mL/min/1.73 m2 or a history of renal replacement therapy. The primary outcome was a composite of major adverse cardiovascular events (MACEs), including nonfatal stroke, nonfatal acute coronary syndrome, major peripheral artery disease, and vascular death. RESULTS: The prevalence of HHcy was 18.5%. Patients with HHcy were more likely to have intracranial (37.4% versus 24.8%; p=0.008) and extracranial (20.9% versus 13.0%; p=0.037) artery stenosis than were those without HHcy. At 1 year, patients with HHcy were at a greater risk of MACE than were those without HHcy (annual rate, 17.8% versus 10.4%; log-rank p=0.033). In the Cox proportional hazard regression models, HHcy was independently associated with an increased risk of MACE in patients with CKD (adjusted hazard ratio [HR], 2.06; 95% confidence interval [CI], 1.02-4.20), whereas HHcy was not predictive of MACE in those without CKD (adjusted HR, 1.00; 95% CI, 0.30-3.32). CONCLUSIONS: Elevated levels of serum homocysteine can be an important modifiable risk factor in stroke patients with CKD, but not in those without CKD.

Changing patterns of pulmonary abnormalities in rheumatoid arthritis.

BACKGROUND: As a first step in identifying the developmental pathways of pulmonary abnormalities in rheumatoid arthritis (RA), we sought to determine the existing and changing patterns of pulmonary abnormalities. METHODS: We conducted a retrospective cohort study of consecutive patients with RA who underwent high-resolution computed tomography before and during biologic therapy. The presence of 20 pulmonary abnormalities and the changes in those abnormalities were recorded. Patterns of pre-existing and changing abnormalities were examined via cluster analysis, and their relationship was also assessed using the Kaplan-Meier method and log-rank test. RESULTS: A total of 208 subjects were included. Pulmonary abnormalities were observed in 70% of patients: 39% had interstitial lung disease, and 55% had airway disease (AD). Several different pulmonary abnormalities were commonly found to co-exist in several patterns in the same patient. In most patients with pulmonary abnormalities, AD was present alone or in combination with other abnormalities. During the observation period (mean 3.2 years), 172 pulmonary abnormalities had changed in 91 patients: 115 pulmonary abnormalities newly emerged, whereas 42 worsened and 25 demonstrated improvement. Pulmonary abnormalities changed in several patterns. Correlations were observed between pre-existing and new/worsening abnormalities at individual and regional levels, such as new ground-glass opacity (GGO) and pre-existing AD, small nodular patterns, and honeycombing. AD was a possible initial abnormality. CONCLUSIONS: Pulmonary abnormalities occurred and changed in several patterns, which suggests the existence of developmental pathways of pulmonary abnormalities. AD may play an important role in the development of these abnormalities, including GGO.

Triglyceride-glucose index as a prognostic marker after ischemic stroke or transient ischemic attack: a prospective observational study.

BACKGROUND: Triglyceride-glucose (TyG) index has been proposed as a simple and credible surrogate for insulin resistance and an independent predictor of cardiovascular outcomes. Due to lack of data on TyG index in stroke, we aimed to evaluate the predictive value of the index for recurrent vascular event risk among stroke patients. METHODS: This was a prospective observational study, in which 866 patients (mean age, 70.1 years; male, 60.9%) with ischemic stroke (n = 781) or transient ischemic attack (n = 85) within 1 week of onset were consecutively enrolled and followed up for 1 year. The TyG index was calculated as ln (fasting triglycerides [mg/dL] × fasting glucose [mg/dL]/2). Patients were divided into 3 groups according to the tertile of TyG index levels: tertile 1, < 8.48; tertile 2, 8.48-9.01; and tertile 3, > 9.01. The primary outcome was a composite of major adverse cardiovascular events (MACE), including nonfatal stroke, nonfatal acute coronary syndrome, and vascular death. RESULTS: The median TyG index was 8.74 (interquartile range, 8.34-9.16). Higher levels of TyG index were significantly associated with increased prevalence of ipsilateral extracranial carotid (P = 0.032) and intracranial (P = 0.003) atherosclerotic stenosis. There were significant differences in the MACE risk between the three groups (annual rate, 8.6%, 11.6%, and 17.3% in the tertile 1, tertile 2, tertile 3 groups, respectively; log-rank P = 0.005). After multivariable adjustments, the TyG index remains to be a significant predictor of MACE, with an adjusted hazard ratio for tertile 3 versus tertile 1 groups (95% confidence interval) of 2.01 (1.16-3.47). Similar results were also found for the risk of recurrent stroke. CONCLUSIONS: TyG index is associated with cervicocerebral atherosclerosis and the MACE risk after a stroke, suggesting the potential value of TyG index to optimize the risk stratification of stroke patients. Trial registration URL:  https://upload.umin.ac.jp . Unique identifier: UMIN000031913.

Two independent modes of kidney stone suppression achieved by AIM/CD5L and KIM-1.

The prevalence of kidney stones is increasing and its recurrence rate within the first 5 years is over 50%. No treatments that prevent the occurrence/recurrence of stones have reached the clinic. Here, we show that AIM (also called CD5L) suppresses stone development and improves stone-associated physical damages. The N-terminal domain of AIM associates with calcium oxalate crystals via charge-based interaction to impede the development of stones, whereas the 2nd and C-terminal domains capture the inflammatory DAMPs to promote their phagocytic removal. Accordingly, when stones were induced by glyoxylate in mice, recombinant AIM (rAIM) injection dramatically reduced stone development. Expression of injury molecules and inflammatory cytokines in the kidney and overall renal dysfunction were abrogated by rAIM. Among various negatively charged substances, rAIM was most effective in stone prevention due to its high binding affinity to crystals. Furthermore, only AIM was effective in improving the physical complaints including bodyweight-loss through its DAMPs removal effect. We also found that tubular KIM-1 may remove developed stones. Our results could be the basis for the development of a comprehensive therapy against kidney stone disease.

[A Survey on the Concomitant Use of Drugs with Enzalutamide in Medical Practice-The Effects and Resultant Decrease in Efficacy].

PURPOSE: Enzalutamide is a potent inducer of cytochrome P450 substrates. Hence, it induces major metabolizing enzyme effects in some of the concomitant drugs, raising the possibility of decreased efficacy. We investigated the actual status of drugs for which precautions for co-administration are indicated during concomitant use with enzalutamide. METHODS: We retrospectively investigated the duration of enzalutamide use, concomitant medications, laboratory values, and events using the medical records of patients prescribed enzalutamide for castration-resistant prostate cancer at the National Cancer Center Hospital from May 2014 to May 2017. RESULTS: The median age of the 107 studied patients was 74 years[range: 53-93], median duration of enzalutamide prescriptions was 120 days[range: 14-1,008], and the median number of concomitant medications(components)was 6[range: 0-16]. Sixty nine patients(64%)were taking drugs that could be affected by enzyme induction. The medications listed in the concomitant use section of the package insert were warfarin(3 patients) and omeprazole(2 patients). In this study, 4 patients(except for 1 on warfarin)were taking other drugs that could be affected by enzyme induction. Events considered to possibly reduce their efficacy during concomitant use with enzalutamide were elevated blood pressure and blood clots. CONCLUSIONS: When enzalutamide is used in combination with other drugs, there exists the possibility that the effect of concomitant medications may be weakened by enzyme induction.

Young gastric cancer patient with high CA19-9 complicated by Trousseau syndrome.

A 47-year-old Japanese woman presented with epigastric discomfort and anorexia. Upper endoscopy showed type 4 advanced gastric cancer in the gastric antrum with stenosis of the pyloric portion. Abdominopelvic CT revealed peritoneal dissemination, and stage IV advanced gastric cancer was diagnosed. Laparoscopic gastrojejunostomy and enterostomy were performed. Trousseau syndrome occurred 7 days post-surgery. Despite appropriate treatment, the patient developed a pulmonary embolism 13 days later and died 18 days post-surgery. Even in young cancer patients without lifestyle disease complications, it is important to pay attention to Trousseau syndrome as part of cancer management.

High salt exacerbates acute kidney injury by disturbing the activation of CD5L/apoptosis inhibitor of macrophage (AIM) protein.

The influence of excess salt intake on acute kidney injury (AKI) has not been examined precisely except for some clinical data, unlike in chronic kidney disease. Here, we addressed the influence of high salt (HS) on AKI and its underlying mechanisms in terms of the activity of circulating apoptosis inhibitor of macrophage (AIM, also called CD5L) protein, a facilitator of AKI repair. HS loading in mice subjected to ischemia/reperfusion (IR) resulted in high mortality with advanced renal tubular obstruction and marked exacerbation in biomarkers of proximal renal tubular damage. This AKI exacerbation appeared to be caused mainly by the reduced AIM dissociation from IgM pentamer in serum, as IgM-free AIM is indispensable for the removal of intratubular debris to facilitate AKI repair. Injection of recombinant AIM (rAIM) ameliorated the AKI induced by IR/HS, dramatically improving the tubular damage and mouse survival. The repair of lethal AKI by AIM was dependent on AIM/ kidney injury molecule-1 (KIM-1) axis, as rAIM injection was not effective in KIM-1 deficient mice. Our results demonstrate that the inhibition of AIM dissociation from IgM is an important reason for the exacerbation of AKI by HS, that AIM is a strong therapeutic tool for severe AKI.

AIM/CD5L attenuates DAMPs in the injured brain and thereby ameliorates ischemic stroke.

The sterile inflammation caused by damage-associated molecular patterns (DAMPs) worsens the prognosis following primary injury such as ischemic stroke. However, there are no effective treatments to regulate DAMPs. Here, we report that AIM (or CD5L) protein reduces sterile inflammation by attenuating DAMPs and that AIM administration ameliorates the deleterious effects of ischemic stroke. AIM binds to DAMPs via charge-based interactions and disulfide bond formation. This AIM association promotes the phagocytic removal of DAMPs and neutralizes DAMPs by impeding their binding to inflammatory receptors. In experimental stroke, AIM-deficient mice exhibit severe neurological damage and higher mortality with greater levels of DAMPs and associated inflammation in the brain than wild-type mice, in which brain AIM levels increase following stroke onset. Recombinant AIM administration reduces sterile inflammation in the infarcted region, leading to a profound reduction of animal mortality. Our findings provide a basis for the therapies targeting DAMPs to improve ischemic stroke.

Long-term outcome of Wilson's disease complicated by liver disease.

BACKGROUND AND AIM: Wilson's disease (WD) is a rare inherited disease that causes systemic copper accumulation. This study examined the long-term course of WD patients with liver disease. METHODS: The 12 patients (9 female patients) enrolled in the study had a median age of 28 years (range: 19-57 years) at their first visit to our hospital. Clinical course and fibrosis markers were assessed in all patients. RESULTS: The median age at diagnosis was 24 years (range: 5-42 years). One patient had acute liver failure (ALF) and 11 patients had chronic liver disease (CLD, 5 with cirrhosis). The patients were followed-up for >20 years. The patient with ALF underwent liver transplantation; the postoperative course during the subsequent 20 years was good. Of the six patients with CLD, liver cirrhosis developed in four patients with interrupted chelating therapy. Two of the patients with cirrhosis died; one of these two patients died at 21 years after liver transplantation. However, the remaining patients with continued treatment exhibited a favorable clinical course for 30 years and none developed hepatocellular carcinoma (HCC). The duration of chelation therapy was significantly negatively correlated (P < 0.05) with the fibrosis-4 index or aspartate aminotransferase to platelet ratio index (APRI) score at the last visit; lower values were indicative of greater treatment success. Patients with an APRI score ≥1.5 had a significantly worse prognosis (P < 0.05). CONCLUSION: Long-term survival of patients with WD was achieved without worsened liver function or carcinogenesis with appropriate treatment. Treatment disruption should be avoided.

Crucial Role of AIM/CD5L in the Development of Glomerular Inflammation in IgA Nephropathy.

BACKGROUND: IgA nephropathy (IgAN) begins with aberrant IgA deposition in glomeruli, progresses to IgM/IgG/complement codeposition, and results in chronic inflammation and glomerular damage. However, the mechanism that drives such phlogogenic cascade has been unclear. Recently, apoptosis inhibitor of macrophage (AIM) protein was shown to modulate macrophages' function in various pathologic conditions, thereby profoundly affecting the progression of renal disorders, including AKI. A spontaneous IgAN model, grouped ddY (gddY) mouse, revealed the requirement of AIM for the overall inflammatory glomerular injury following IgA deposition. METHODS: We established an AIM-deficient IgAN model (AIM-/- gddY) using CRISPR/Cas9 and compared its phenotype with that of wild-type gddY with or without recombinant AIM administration. An IgA-deficient IgAN model (IgA-/- gddY) was also generated to further determine the role of AIM. RESULTS: In both human and murine IgAN, AIM colocalized with IgA/IgM/IgG in glomeruli, whereas control kidneys did not exhibit AIM deposition. Although AIM-/- gddY showed IgA deposition at levels comparable with those of wild-type gddY, they did not exhibit glomerular accumulation of IgM/IgG complements, CD45+ leukocyte infiltration, and upregulation of inflammatory/fibrogenic genes, indicating protection from glomerular lesions and proteinuria/hematuria. Recombinant AIM administration reconstituted the IgAN phenotype, resulting in IgM/IgG/complement IgA codeposition. Neither spontaneous IgM/IgG codeposition nor disease was observed in IgA-/- gddY mice. CONCLUSIONS: AIM may contribute to stable immune complex formation in glomeruli, thereby facilitating IgAN progression. Therefore, AIM deposition blockage or disassociation from IgM/IgG may present a new therapeutic target on the basis of its role in IgAN inflammation initiation.

Successful treatment of non-HIV progressive multifocal leukoencephalopathy: case report and literature review.

BACKGROUND: Progressive multifocal leukoencephalopathy (PML) is a subacute onset demyelinating disease caused by JC virus and characterized by multifocal involvement of the subcortical white matter and cerebellar hemispheres or peduncles on magnetic resonance imaging (MRI). However, non-HIV PML patients with brain lesions limited to the cerebellum and brainstem have not been well characterized. METHODS: We report a 68-year-old man with systemic lupus erythematosus under treatment with immunosuppressants who developed non-HIV PML with brain lesions limited to the cerebellum and brainstem and successfully treated with a combination of mefloquine and mirtazapine. We performed a literature review to characterize patients with non-HIV PML with brain lesions limited to the cerebellum and brainstem. RESULTS: Eight cases with non-HIV brainstem/cerebellar form PML were identified including our case. All cases had compromised status related underlying diseases. Four (50%) had a good prognosis. Five cases were treated, including 3 with favourable outcomes. Between the good prognosis group (n = 4) and the poor prognosis group (n = 4), treatment status for PML and the interval between the initial manifestation and diagnosis did not differ. Among those who performed contrast-enhanced brain imaging, lesion enhancement was related to good prognosis (good prognosis group vs. poor prognosis group; 100% vs. 0%). CONCLUSION: PML should be considered in the differential diagnosis of brain lesions limited to the cerebellum and brainstem in immunocompromised patients. The presence of immune response against JC virus and inflammatory reactions may indicate good prognosis in non-HIV brainstem/cerebellar form PML.

AIM-deficient mouse fed a high-trans fat, high-cholesterol diet: a new animal model for nonalcoholic fatty liver disease.

Owing to changes in lifestyle, nonalcoholic fatty liver disease (NAFLD) is becoming a common form of chronic liver injury. NAFLD comprises a wide variety of disease stages, from simple steatosis to nonalcoholic steatohepatitis, which is a risk factor for the development of hepatocellular carcinoma (HCC). Because animal models for NAFLD are needed to investigate the precise pathogenesis, we aimed to establish a new mouse model employing mice deficient for apoptosis inhibitor of macrophage (AIM-/-), which exhibit accelerated lipid storage in the liver and high susceptibility to developing HCC in response to a high-fat diet (HFD). AIM-/- mice were fed the D09100301 diet, which contains 40 kcal% fat (trans fat 30 kcal%), high cholesterol (2%), and 40 kcal% carbohydrates (20 kcal% fructose), and then features of obesity and NAFLD including steatosis, inflammation, fibrosis, and HCC development were analyzed. Although a comparable grade of liver steatosis was promoted in AIM-/- mice by the D09100301 diet and the standard HFD (60 kcal% largely lard fat), significantly less lipid storage in visceral fat was observed when the mice were fed the D09100301 diet. Accelerated liver inflammation was promoted by the D09100301 diet compared with the HFD, but interestingly, HCC development was decreased in mice fed the D09100301 diet. Our findings suggest that AIM-/- mice fed the D09100301 diet exhibited a phenotype that resembled nonobese NAFLD patients and thus could be an appropriate tool to study the pathophysiology by which obesity increases the risk of HCC.

The IgM pentamer is an asymmetric pentagon with an open groove that binds the AIM protein.

Soluble immunoglobulin M (IgM) forms a pentamer containing a joining (J) chain polypeptide. While IgM pentamer has various immune functions, it also behaves as a carrier of circulating apoptosis inhibitor of macrophage (AIM; also called CD5L) protein that facilitates repair during different diseases. AIM binds to the IgM pentamer solely in the presence of the J chain. Here, using a single-particle negative-stain electron microscopy, we found that the IgM pentamer exhibits an asymmetric pentagon containing one large gap, which is markedly different from the textbook symmetric pentagon model. A single AIM molecule specifically fits into the gap, cross-bridging two IgM-Fc that form the edges of the gap through a disulfide bond at one side and a charge-based interaction at the other side. The discovery of the bona fide shape of the IgM pentamer advances our structural understanding of the pentameric IgM and its binding mode with AIM.

A scavenging system against internal pathogens promoted by the circulating protein apoptosis inhibitor of macrophage (AIM).

An internal system designed to ward off and remove unnecessary or hazardous materials is intrinsic to animals. In addition to exogenous pathogens, a number of self-molecules, such as apoptotic or necrotic dead cells, their debris, and the oxides or peroxides of their cellular components, are recognized as extraneous substances. It is essential to eliminate these internal pathogens as quickly as possible because their accumulation can cause chronic inflammation as well as autoimmune responses, possibly leading to onset or progression of certain diseases. Apoptosis inhibitor of macrophage (AIM, also called CD5L) is a circulating protein that is a member of the scavenger receptor cysteine-rich superfamily, and we recently found that during acute kidney injury, AIM associates with intraluminal dead cell debris accumulated in renal proximal tubules and enhances clearance of luminal obstructions, thereby facilitating repair. Thus, AIM acts as a marker for phagocytes so that they can efficiently recognize and engulf the debris as their targets. In this chapter, we give an overview of the professional and non-professional phagocytes, and how soluble scavenging molecules such as AIM contribute to improvement of diseases by stimulating phagocytic activity.