The Diagnostic Potential of Circulating Autoantibodies to Amyloid-ß in Alzheimer's Disease.

BACKGROUND: The profile of naturally occurring antibodies to amyloid-ß (NAbs-Aß) is altered in patients with Alzheimer's disease (AD). However, the diagnostic potential of NAbs-Aß for AD is not clear yet. OBJECTIVE: This study aims to investigate the diagnostic capacities of NAbs-Aß for AD. METHODS: A total of 40 AD patients and 40 cognitively normal (CN) controls were enrolled in this study. Levels of NAbs-Aß were detected by ELISA. The correlations of NAbs-Aß levels with cognitive function and AD-associated biomarkers were examined by Spearman correlation analysis. Diagnostic abilities of NAbs-Aß were evaluated by the receiver operating characteristic (ROC) curve analyses. The integrative diagnostic models were established by logistic regression models. RESULTS: We found that NAbs-Aß7-18 had the highest diagnostic capability (AUC = 0.72) among all single NAbs-Aß. The combined model (NAbs-Aß7-18, NAbs-Aß19-30, and NAbs-Aß25-36) had a noticeable improvement (AUC = 0.84) in the diagnostic capacity compared with each single NAbs-Aß. CONCLUSION: NAbs-Aßs are promising in the diagnosis of AD. Further investigations are needed to confirm the translational potential of this diagnostic strategy.

Physiological ß-amyloid clearance by the liver and its therapeutic potential for Alzheimer's disease.

Cerebral amyloid-ß (Aß) accumulation due to impaired Aß clearance is a pivotal event in the pathogenesis of Alzheimer's disease (AD). Considerable brain-derived Aß is cleared via transporting to the periphery. The liver is the largest organ responsible for the clearance of metabolites in the periphery. Whether the liver physiologically clears circulating Aß and its therapeutic potential for AD remains unclear. Here, we found that about 13.9% of Aß42 and 8.9% of Aß40 were removed from the blood when flowing through the liver, and this capacity was decreased with Aß receptor LRP-1 expression down-regulated in hepatocytes in the aged animals. Partial blockage of hepatic blood flow increased Aß levels in both blood and brain interstitial fluid. The chronic decline in hepatic Aß clearance via LRP-1 knockdown specific in hepatocytes aggravated cerebral Aß burden and cognitive deficits, while enhancing hepatic Aß clearance via LRP-1 overexpression attenuated cerebral Aß deposition and cognitive impairments in APP/PS1 mice. Our findings demonstrate that the liver physiologically clears blood Aß and regulates brain Aß levels, suggesting that a decline of hepatic Aß clearance during aging could be involved in AD development, and hepatic Aß clearance is a novel therapeutic approach for AD.

Associations Between Plasma Klotho with Renal Function and Cerebrospinal Fluid Amyloid-ß Levels in Alzheimer's Disease: The Chongqing Ageing & Dementia Study.

BACKGROUND: The kidney-brain crosstalk has been involved in Alzheimer's disease (AD) with the mechanism remaining unclear. The anti-aging factor Klotho was reported to attenuate both kidney injury and AD pathologies. OBJECTIVE: To investigate whether plasma Klotho participated in kidney-brain crosstalk in AD. METHODS: We enrolled 33 PiB-PET-positive AD patients and 33 amyloid-ß (Aß)-negative age- and sex-matched cognitively normal (CN) controls from the Chongqing Ageing & Dementia Study (CADS). The levels of plasma Klotho, Aß, and tau in the cerebrospinal fluid (CSF) were measured by enzyme-linked immunosorbent assay. RESULTS: We found higher plasma Klotho and lower estimated glomerular filtration rate (eGFR) levels in AD patients compared with CN. The eGFR was positively associated with Aß42, Aß40 levels in CSF and negatively associated with CSF T-tau levels. Plasma Klotho levels were both negatively correlated with CSF Aß42 and eGFR. Mediation analysis showed that plasma Klotho mediated 24.96% of the association between eGFR and CSF Aß42. CONCLUSION: Renal function impacts brain Aß metabolism via the kidney-brain crosstalk, in which the plasma Klotho may be involved as a mediator. Targeting Klotho to regulate the kidney-brain crosstalk provides potential therapeutic approaches for AD.

Elevated Levels of Naturally-Occurring Autoantibodies Against the Extracellular Domain of p75NTR Aggravate the Pathology of Alzheimer's Disease.

The extracellular domain (p75ECD) of p75 neurotrophin receptor (p75NTR) antagonizes Aß neurotoxicity and promotes Aß clearance in Alzheimer's disease (AD). The impaired shedding of p75ECD is a key pathological process in AD, but its regulatory mechanism is largely unknown. This study was designed to investigate the presence and alterations of naturally-occurring autoantibodies against p75ECD (p75ECD-NAbs) in AD patients and their effects on AD pathology. We found that the cerebrospinal fluid (CSF) level of p75ECD-NAbs was increased in AD, and negatively associated with the CSF levels of p75ECD. Transgenic AD mice actively immunized with p75ECD showed a lower level of p75ECD and more severe AD pathology in the brain, as well as worse cognitive functions than the control groups, which were immunized with Re-p75ECD (the reverse sequence of p75ECD) and phosphate-buffered saline, respectively. These findings demonstrate the impact of p75ECD-NAbs on p75NTR/p75ECD imbalance, providing a novel insight into the role of autoimmunity and p75NTR in AD.

The association of serum uric acid with cognitive impairment and ATN biomarkers.

Background: Cognitive impairment (CI) has become a worldwide health problem. The relationship between CI and uric acid (UA) is contradictory. Objective: We included participants with a full spectrum of CI, from cognitively unimpaired (CU) to dementia, from the Chongqing Ageing & Dementia Study (CADS). Methods: First, we identified the relationships between serum UA (sUA) and cognitive function in different stages of CI. Second, we analyzed these relationships among different stages and types of CI. Finally, we explored the association between sUA and amyloid/tangle/neurodegeneration (ATN) biomarkers. Results: We recruited 427 participants from the CADS, including 382 participants with mini-mental state examination (MMSE) evaluation. The levels of sUA were positively correlated with MMSE scores (p < 0.001), and the correlation was prominent in the course of dementia and in the type of Alzheimer's disease (AD). The levels of UA had a positive correlation with plasma amyloid-ß 42 (Aß42) (p = 0.004). Higher levels of sUA weakened the correlation of MMSE scores with CSF ATN biomarkers and the correlation of CSF Aß42 with tau. Conclusion: UA is positively correlated with cognitive function, especially in the advanced stage of AD. The probable neuroprotective effects of sUA mainly act on Aß42 and the downstream pathological cascade.

Establishment of combined diagnostic models of Alzheimer's disease in a Chinese cohort: the Chongqing Ageing & Dementia Study (CADS).

Cerebrospinal fluid (CSF) biomarkers are essential for the accurate diagnosis of Alzheimer's disease (AD), yet their measurement levels vary widely across centers and regions, leaving no uniform cutoff values to date. Diagnostic cutoff values of CSF biomarkers for AD are lacking for the Chinese population. As a member of the Alzheimer's Association Quality Control program for CSF biomarkers, we aimed to establish diagnostic models based on CSF biomarkers and risk factors for AD in a Chinese cohort. A total of 64 AD dementia patients and 105 age- and sex-matched cognitively normal (CN) controls from the Chongqing Ageing & Dementia Study cohort were included. CSF Aß42, P-tau181, and T-tau levels were measured by ELISA. Combined biomarker models and integrative models with demographic characteristics were established by logistic regression. The cutoff values to distinguish AD from CN were 933 pg/mL for Aß42, 48.7 pg/mL for P-tau181 and 313 pg/mL for T-tau. The AN model, including Aß42 and T-tau, had a higher diagnostic accuracy of 89.9%. Integrating age and APOE ε4 status to AN model (the ANA'E model) increased the diagnostic accuracy to 90.5% and improved the model performance. This study established cutoff values of CSF biomarkers and optimal combined models for AD diagnosis in a Chinese cohort.

Naturally-Occurring Antibodies Against Bim are Decreased in Alzheimer's Disease and Attenuate AD-type Pathology in a Mouse Model.

Increased neuronal apoptosis is an important pathological feature of Alzheimer's disease (AD). The Bcl-2-interacting mediator of cell death (Bim) mediates amyloid-beta (Aß)-induced neuronal apoptosis. Naturally-occurring antibodies against Bim (NAbs-Bim) exist in human blood, with their levels and functions unknown in AD. In this study, we found that circulating NAbs-Bim were decreased in AD patients. Plasma levels of NAbs-Bim were negatively associated with brain amyloid burden and positively associated with cognitive functions. Furthermore, NAbs-Bim purified from intravenous immunoglobulin rescued the behavioral deficits and ameliorated Aß deposition, tau hyperphosphorylation, microgliosis, and neuronal apoptosis in APP/PS1 mice. In vitro investigations demonstrated that NAbs-Bim were neuroprotective against AD through neutralizing Bim-directed neuronal apoptosis and the amyloidogenic processing of amyloid precursor protein. These findings indicate that the decrease of NAbs-Bim might contribute to the pathogenesis of AD and immunotherapies targeting Bim hold promise for the treatment of AD.

Associations of plasma soluble CD22 levels with brain amyloid burden and cognitive decline in Alzheimer's disease.

CD22 has been suggested to contribute to Alzheimer's disease (AD) pathogenesis by inhibiting microglial amyloid ß (Aß) phagocytosis. Soluble CD22 (sCD22) generated by cleavage from cell membranes may be a marker of inflammation and microglial dysfunction; but alterations of sCD22 levels in AD and their correlation with AD biomarkers remain unclear. Plasma sCD22 levels were measured in cognitively normal non-AD participants and patients with preclinical AD and AD dementia from a Chinese cohort and the Australian Imaging, Biomarkers and Lifestyle Flagship Study of Ageing. Plasma sCD22 levels were elevated in patients with preclinical and dementia AD. Plasma sCD22 levels were negatively correlated with cerebrospinal fluid (CSF) Aß42 levels and Aß42/Aß40, and positively correlated with CSF phosphorylated tau levels and brain Aß burden, but negatively correlated with cognitive function. Moreover, higher plasma sCD22 levels were associated with faster cognitive decline during follow-up. These findings suggest that CD22 plays important roles in AD development, and that sCD22 is a potential biomarker for AD.

Circulating Naturally Occurring Antibodies to P2RY2 Are Decreased in Alzheimer's Disease.

BACKGROUND: The G protein-coupled receptor P2RY2 protein of the purinergic receptor family is involved in the pathogenesis of Alzheimer's disease (AD). Naturally occurring antibodies against P2RY2 (NAbs-P2RY2) are present in human plasma, with their clinical relevance in AD unknown. OBJECTIVE: To explore the alteration of NAbs-P2RY2 in AD patients and its associations with biomarkers and cognition of AD patients. METHODS: The levels of naturally occurring antibodies against the four extracellular domains of P2RY2 (NAbs-P2RY2-1, NAbs-P2RY2-2, NAbs-P2RY2-3, and NAbs-P2RY2-4) were measured in the plasma of 55 AD patients, 28 non-AD dementia patients, and 70 cognitively normal participants. The correlations of autoantibody levels with cognitive scale scores, AD plasma biomarkers, and brain amyloid burden were examined. RESULTS: NAbs-P2RY2-1, NAbs-P2RY2-3, and NAbs-P2RY2-4 were reduced in AD patients. Plasma levels of NAbs-P2RY2-2 and NAbs-P2RY2-3 levels were positively associated with cognitive and functional performances. Among these antibodies, plasma NAbs-P2RY2-2 levels were positively associated with plasma amyloid-ß 42 levels. While plasma NAbs-P2RY2-3 levels were negatively associated with brain amyloid burden in AD patients. CONCLUSION: These findings indicate an alteration of humoral immunity against P2RY2 in AD patients. Further mechanistical investigations are needed to reveal the role of NAbs-P2RY2 in the pathogenesis of AD.

Dynamic changes of CSF sPDGFRß during ageing and AD progression and associations with CSF ATN biomarkers.

BACKGROUND: Loss of brain capillary pericyte is involved in the pathologies and cognitive deficits in Alzheimer's disease (AD). The role of pericyte in early stage of AD pathogenesis remains unclear. METHODS: We investigated the dynamic changes of soluble platelet-derived growth factor receptor ß (sPDGFRß) in cerebrospinal fluid (CSF), a marker of brain pericyte injury, in transition from normal ageing to early AD in a cognitively unimpaired population aged 20 to 90 years. Association between sPDGFRß and ATN biomarkers were analyzed. RESULTS: In lifetime, CSF sPDGFRß continually increased since age of 20 years, followed by the increases of phosphorylated tau-181 (P-tau181) and total tau (T-tau) at the age of 22.2 years and 31.7 years, respectively; CSF Aß42 began to decline since the age of 39.6 years, indicating Aß deposition. The natural trajectories of biomarkers suggest that pericyte injury is an early event during transition from normal status to AD, even earlier than Aß deposition. In AD spectrum, CSF sPDGFRß was elevated in preclinical stage 2 and participants with suspected non-AD pathophysiologies. Additionally, CSF sPDGFRß was positively associated with P-tau181 and T-tau independently of Aß42, and significantly strengthened the effects of Aß42 on P-tau181, suggesting that pericyte injury accelerates Aß-mediated tau hyperphosphorylation. CONCLUSIONS: Our results suggest that pericyte injury contributes to AD progression in the early stage in an Aß-independent pathway. Recovery of pericyte function would be a target for prevention and early intervention of AD.

Polysaccharide Krestin Prevents Alzheimer's Disease-type Pathology and Cognitive Deficits by Enhancing Monocyte Amyloid-ß Processing.

Deficits in the clearance of amyloid ß protein (Aß) by the peripheral system play a critical role in the pathogenesis of sporadic Alzheimer's disease (AD). Impaired uptake of Aß by dysfunctional monocytes is deemed to be one of the major mechanisms underlying deficient peripheral Aß clearance in AD. In the current study, flow cytometry and biochemical and behavioral techniques were applied to investigate the effects of polysaccharide krestin (PSK) on AD-related pathology in vitro and in vivo. We found that PSK, widely used in therapy for various cancers, has the potential to enhance Aß uptake and intracellular processing by human monocytes in vitro. After administration of PSK by intraperitoneal injection, APP/PS1 mice performed better in behavioral tests, along with reduced Aß deposition, neuroinflammation, neuronal loss, and tau hyperphosphorylation. These results suggest that PSK holds promise as a preventive agent for AD by strengthening the Aß clearance by blood monocytes and alleviating AD-like pathology.

Physiological clearance of amyloid-beta by the kidney and its therapeutic potential for Alzheimer's disease.

Amyloid-ß (Aß) accumulation in the brain is a pivotal event in the pathogenesis of Alzheimer's disease (AD), and its clearance from the brain is impaired in sporadic AD. Previous studies suggest that approximately half of the Aß produced in the brain is cleared by transport into the periphery. However, the mechanism and pathophysiological significance of peripheral Aß clearance remain largely unknown. The kidney is thought to be responsible for Aß clearance, but direct evidence is lacking. In this study, we investigated the impact of unilateral nephrectomy on the dynamic changes in Aß in the blood and brain in both humans and animals and on behavioural deficits and AD pathologies in animals. Furthermore, the therapeutic effects of the diuretic furosemide on Aß clearance via the kidney were assessed. We detected Aß in the kidneys and urine of both humans and animals and found that the Aß level in the blood of the renal artery was higher than that in the blood of the renal vein. Unilateral nephrectomy increased brain Aß deposition; aggravated AD pathologies, including Tau hyperphosphorylation, glial activation, neuroinflammation, and neuronal loss; and aggravated cognitive deficits in APP/PS1 mice. In addition, chronic furosemide treatment reduced blood and brain Aß levels and attenuated AD pathologies and cognitive deficits in APP/PS1 mice. Our findings demonstrate that the kidney physiologically clears Aß from the blood, suggesting that facilitation of Aß clearance via the kidney represents a novel potential therapeutic approach for AD.

Blood cell-produced amyloid-ß induces cerebral Alzheimer-type pathologies and behavioral deficits.

It is traditionally believed that cerebral amyloid-beta (Aß) deposits are derived from the brain itself in Alzheimer's disease (AD). Peripheral cells such as blood cells also produce Aß. The role of peripherally produced Aß in the pathogenesis of AD remains unknown. In this study, we established a bone marrow transplantation model to investigate the contribution of blood cell-produced Aß to AD pathogenesis. We found that bone marrow cells (BMCs) transplanted from APPswe/PS1dE9 transgenic mice into wild-type (Wt) mice at 3 months of age continuously expressed human Aß in the blood, and caused AD phenotypes including Aß plaques, cerebral amyloid angiopathy (CAA), tau hyperphosphorylation, neuronal degeneration, neuroinflammation, and behavioral deficits in the Wt recipient mice at 12 months after transplantation. Bone marrow reconstitution in APPswe/PS1dE9 mice with Wt-BMCs at 3 months of age reduced blood Aß levels, and alleviated brain Aß burden, neuronal degeneration, neuroinflammation, and behavioral deficits in the AD model mice at 12 months after transplantation. Our study demonstrated that blood cell-produced Aß plays a significant role in AD pathogenesis, and the elimination of peripheral production of Aß can decrease brain Aß deposition and represents a novel therapeutic approach for AD.

Critical thinking on amyloid-beta-targeted therapy: challenges and perspectives.

Amyloid-beta (Aß) plays a pivotal role in the pathogenesis of Alzheimer's disease (AD) and has been regarded as the main therapeutic target for AD. However, most of the Aß-targeted clinical trials have not succeeded. Therefore, the Aß-targeted therapeutic strategy on treating this complex disease needs to be re-evaluated. In this review, we analyzed the challenges and critical points of the current anti-Aß therapeutic strategies. In addition to Aß, multiple pathological events such as tau hyperphosphorylation, oxidative stress, and neuroinflammation, which are involved in AD pathogenesis and synergistically drive disease progression, could be important targets for AD treatment. Tertiary prevention strategies are needed for the successful management of AD due to its complex and dynamic pathogenesis. Systemic perspective addressing the disease pathogenesis within and outside the brain, as well as the multidomain intervention targeting risk factors and comorbidities, are important approaches for the therapeutic solutions of AD.

Amyloid-beta uptake by blood monocytes is reduced with ageing and Alzheimer's disease.

Deficits in the clearance of amyloid ß-protein (Aß) play a pivotal role in the pathogenesis of sporadic Alzheimer's disease (AD). The roles of blood monocytes in the development of AD remain unclear. In this study, we sought to investigate the alterations in the Aß phagocytosis function of peripheral monocytes during ageing and in AD patients. A total of 104 cognitively normal participants aged 22-89 years, 24 AD patients, 25 age- and sex-matched cognitively normal (CN) subjects, 15 Parkinson's disease patients (PD), and 15 age- and sex-matched CN subjects were recruited. The Aß uptake by blood monocytes was measured and its alteration during ageing and in AD patients were investigated. Aß1-42 uptake by monocytes decreased during ageing and further decreased in AD but not in PD patients. Aß1-42 uptake by monocytes was associated with Aß1-42 levels in the blood. Among the Aß uptake-related receptors and enzymes, the expression of Toll-like receptor 2 (TLR2) was reduced in monocytes from AD patients. Our findings suggest that monocytes regulate the blood levels of Aß and might be involved in the development of AD. The recovery of the Aß uptake function by blood monocytes represents a potential therapeutic strategy for AD.

Association of Polygenic Risk Score with Age at Onset and Cerebrospinal Fluid Biomarkers of Alzheimer's Disease in a Chinese Cohort.

To evaluate whether the polygenic profile modifies the development of sporadic Alzheimer's disease (sAD) and pathological biomarkers in cerebrospinal fluid (CSF), 462 sAD patients and 463 age-matched cognitively normal (CN) controls were genotyped for 35 single-nucleotide polymorphisms (SNPs) that are significantly associated with sAD. Then, the alleles found to be associated with sAD were used to build polygenic risk score (PRS) models to represent the genetic risk. Receiver operating characteristic (ROC) analyses and the Cox proportional hazards model were used to evaluate the predictive value of PRS for the sAD risk and age at onset. We measured the CSF levels of Aß42, Aß42/Aß40, total tau (T-tau), and phosphorylated tau (P-tau) in a subgroup (60 sAD and 200 CN participants), and analyzed their relationships with the PRSs. We found that 14 SNPs, including SNPs in the APOE, BIN1, CD33, EPHA1, SORL1, and TOMM40 genes, were associated with sAD risk in our cohort. The PRS models built with these SNPs showed potential for discriminating sAD patients from CN controls, and were able to predict the incidence rate of sAD and age at onset. Furthermore, the PRSs were correlated with the CSF levels of Aß42, Aß42/Aß40, T-tau, and P-tau. Our study suggests that PRS models hold promise for assessing the genetic risk and development of AD. As genetic risk profiles vary among populations, large-scale genome-wide sequencing studies are urgently needed to identify the genetic risk loci of sAD in Chinese populations to build accurate PRS models for clinical practice.

The Correlations Between Plasma Fibrinogen With Amyloid-Beta and Tau Levels in Patients With Alzheimer's Disease.

Recent studies show that fibrinogen plays a role in the pathogenesis of Alzheimer's disease (AD), which may be crucial to neurovascular damage and cognitive impairment. However, there are few clinical studies on the relationship between fibrinogen and AD. 59 11C-PiB-PET diagnosed AD patients and 76 age- and gender-matched cognitively normal controls were included to analyze the correlation between plasma ß-amyloid (Aß) and tau levels with fibrinogen levels. 35 AD patients and 76 controls with cerebrospinal fluid (CSF) samples were included to further analyze the correlation between CSF Aß and tau levels with fibrinogen levels. In AD patients, plasma fibrinogen levels were positively correlated with plasma Aß40 and Aß42 levels, and negatively correlated with CSF Aß42 levels. Besides, fibrinogen levels were positively correlated with CSF total tau (t-tau), and phosphorylated tau-181 (p-tau) levels and positively correlated with the indicators of Aß deposition in the brain, such as t-tau/Aß42, p-tau/Aß42 levels. In normal people, fibrinogen levels lack correlation with Aß and tau levels in plasma and CSF. This study suggests that plasma fibrinogen levels are positively correlated with Aß levels in the plasma and brain in AD patients. Fibrinogen may be involved in the pathogenesis of AD.

Association of the Polygenic Risk Score with the Incidence Risk of Parkinson's Disease and Cerebrospinal Fluid α-Synuclein in a Chinese Cohort.

Parkinson's disease (PD) is attributed to interactions among genes and environmental and lifestyle factors, but the genetic architecture of PD is complex and not completely understood. To evaluate whether the genetic profile modifies PD development and cerebrospinal fluid (CSF) pathological biomarkers, we enrolled 418 PD patients and 426 age- and sex-matched normal controls. Forty-six single nucleotide polymorphisms (SNPs) that were reported to be significantly associated with PD in large-scale genome-wide association studies (GWASs) were genotyped and analysed. The alleles associated with PD were used to build polygenic risk score (PRS) models to represent polygenic risk. The Cox proportional hazards model and receiver operating characteristic (ROC) analyses were used to evaluate the prediction value of the PRS for PD risk and age at onset. The CSF α-synuclein levels were measured in a subgroup of control subjects (n = 262), and its relationship with the PRS was analysed. We found that some SNPs identified from other populations had significant correlations with PD in our Chinese cohort. The PRS we built had prediction value for PD risk and age at onset. The CSF α-synuclein level had no correlation with the PRS in normal subjects.

Bhargavaea changchunensis sp. nov. isolated from soil in China.

A Gram-staining-positive, aerobic, rod-shaped (201802YP6T) bacteria was isolated from soil, Northeast of China. Growth occurred at 10-40 °C (optimum 25-30 °C), at pH 6.0-8.0 (optimum 7.0) and at 0-2% NaCl. Based on 16S rRNA gene sequence analysis, the nearest phylogenetic neighbors of strain 201802YP6T were identified as Bhargavaea cecembensis DSE10T (99.52%), Bhargavaea beijingensis ge10T (99.45%), Bhargavaea indica KJW98T (99.45%), Bhargavaea ullalensis ZMA19T (98.81%), and Bhargavaea ginsengi ge14T (98.76%). Levels of similarity among strain 201802YP6T and other Bhargavaea species were lower than 98.76%. GyrB amino acid sequence-based analysis supported the phylogenetic position and also distinguished strain 201802YP6T from the other species of the genus Bhargavaea. DNA-DNA hybridization values between strain 201802YP6T and B. cecembensis, B. beijingensis, B. indica, B. ullalensis, B. ginsengi were 43.5%, 43%, 32.5%, 30.5% and 20.4%, respectively. The DNA G + C content of strain 201802YP6T was 51.23 mol%. The average nucleotide identity (ANI) of the draft genome was 87.04% to B. cecembensis DSE10T. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, glycolipids, phosphatidylethanolamine, and phosphatidyllipid. The predominant menaquinone was MK-8. The major fatty acids were iso-C15:0 (39.91%), anteiso-C15:0 (28.86%), anteiso-C17:0 (6.30%) and C16:0 (6.13%). On the basis of the phylogenetic analysis, chemotaxonomic data, physiological characteristics and DNA-DNA hybridization data, strain 201802YP6T represents a novel species of the genus Bhargavaea, for which the name Bhargavaea changchunensis sp. nov. is proposed. The type strain is 201802YP6T (= CGMCC 1.13508T = KCTC 33975T).