Reduced Number of Remaining or Healthy Teeth in Patients with Type 2 Diabetes Mellitus: A Cross-sectional Study Assessed by Dentists or Dental Hygienists in Japan.

Objective This study assessed the relationships between oral health (number of remaining and healthy teeth and periodontal disease) and type 2 diabetes mellitus (T2DM) to contribute to improved patient care. Patients We conducted a cross-sectional cohort study of consecutive patients being regularly treated for chronic diseases (T2DM, hypertension, and dyslipidemia). A dentist or dental hygienist accurately evaluated the oral environment. Patients with fewer than 20 teeth were classified as having reduced remaining teeth (RRT). Results A total of 267 patients were enrolled, including 153 patients (57%) with T2DM and 114 without (43%). Patients with T2DM had 3 fewer remaining teeth on average than those without DM [median: 22 (interquartile range (IQR): 11-27) vs. median: 25 (IQR: 17.3-28), p=0.02]. In addition, patients with T2DM had 4 fewer healthy teeth on average than those without DM [median: 8 (IQR: 2.8-15) vs. median: 12 (IQR: 6-16), p=0.02]. The frequency of RRT was higher in the T2DM group (n=63; 41%) than in the non-DM group (n=31; 27%, p=0.02). Multivariable logistic regression for the presence of RRT in the T2DM group found that age [odds ratio (OR), 1.08; 95% confidence interval (CI), 1.03-1.13; p<0.01] and regular dental consultations (OR, 0.28; 95% CI, 0.10-0.76; p=0.01) were independently and significantly associated. Conclusion The number of remaining or healthy teeth was significantly lower in patients with T2DM than in those without T2DM in current Japanese clinical practice. Regular dental consultation is recommended to preserve remaining teeth in patients with T2DM.

Potential Identification of Type 2 Diabetes with Elevated Insulin Clearance.

BACKGROUND: Decreased blood insulin concentrations resulting from reduced pancreatic ß-cell insulin secretion and elevated insulin clearance (IC) could be involved in impaired glucose metabolism in diabetes. Recently, we reported a patient with type 2 diabetes mellitus (T2DM) who had decreased blood insulin concentrations and elevated IC. METHODS: For this study, we recruited patients with newly diagnosed, treatment-naïve T2DM and measured the metabolic clearance rate of insulin (MCRI) determined by a hyperinsulinemic-euglycemic clamp examination. We defined elevated IC as an MCRI of more than 700 ml/min/m2. Using this tentative cutoff, we identified patients with T2DM with elevated IC and investigated their clinical characteristics. RESULTS: We enrolled 101 patients in this study; 78.2% were men. Patients had a mean age of 54.1 years, a median body-mass index (BMI) of 25.1 kg/m2 (interquartile range [IQR], 22.9 to 28.4 kg/m2), a median hemoglobin A1c of 10.0% (IQR, 8.0 to 12.3%), and a median MCRI of 655 ml/min/m2 (IQR, 562 to 810 ml/min/m2). Our case definition for elevated IC was met by 44 patients whose median MCRI was 842 ml/min/m2 (IQR, 747 to 975 ml/min/m2) compared with those without elevated IC (570 ml/min/m2; IQR, 500 to 628 ml/min/m2). On the basis of this division, fasting blood glucose and insulin levels were 178 mg/dl (IQR, 140 to 218 mg/dl) and 4.2 mU/l (IQR, 2.7 to 5.5 mU/l), respectively, in patients with elevated IC compared with 146 mg/dl (IQR, 128 to 188 mg/dl) and 9.6 mU/l (IQR, 6.6 to 14.9 mU/l), respectively, in patients without elevated IC. The BMI of patients with elevated IC was 22.9 kg/m2 (IQR, 20.7 to 24.2 kg/m2) compared with 27.3 kg/m2 (IQR, 25.2 to 29.4 kg/m2) in patients who did not have elevated IC. There were no clinically significant differences in renal or hepatic function test results. CONCLUSIONS: Our data suggest that there is a group of patients with T2DM with elevated IC, and that they are nonobese and have decreased blood insulin concentrations. If confirmed, this novel form of T2DM could affect the treatment of such patients. (UMIN Clinical Trials Registry number, UMIN000032014.)

Changes in urinary glucose concentration and body weight in patients treated with the selective SGLT2 inhibitor luseogliflozin.

AIMS: We investigated the effects of the SGLT2 inhibitor luseogliflozin on blood and urinary glucose and body weight. METHODS: Luseogliflozin 2.5 mg was administered once daily for 24 weeks to 30 outpatients with type 2 diabetes. Urinary glucose concentration, continuous glucose monitoring values, HbA1c, fasting glucose, and body weight were evaluated. Correlations with urinary glucose, subcutaneous/visceral fat mass, insulin, EPA/AA ratio, plasma free fatty acids, ghrelin, blood ketones, plasma 1,5-anhydro-D-glucitol were evaluated. RESULTS: Urinary glucose significantly increased from 11.1 ± 11.8 g at Week -4 to 84.5 ± 46.8 g at Week 24. HbA1c significantly declined from 7.88 ± 0.88% to 7.36 ± 1.13% at Week 24. Mean blood glucose significantly decreased from 149.6 ± 41.8 to 131.6 ± 31.1 mg/dL at Week 24. Subcutaneous and visceral fat mass was also significantly decreased, as were AST and ALT (P < 0.01). Blood urea nitrogen was significantly increased, and urate significantly decreased from 5.04 ± 1.07 to 4.53 ± 0.94 mg/dL. The homeostasis model assessment ratio remained significantly improved throughout the treatment period. Acyl ghrelin levels remained constant but des-acyl ghrelin increased significantly. CONCLUSIONS: Luseogliflozin monotherapy resulted in an improvement in blood glucose, a decrease in body weight, and decreased insulin resistance. Luseogliflozin appears to be an effective therapy for obese diabetics.

A Non-obese, Treatment-Naive Japanese Diabetic Patient With Elevated Insulin Clearance and Hyperglycemia Under Enhanced Insulin Sensitivity and Increased Insulin Secretion: Elevated Insulin Clearance as Type 2 Japanese Diabetes Mellitus (T2JDM).

Diabetes mellitus is a heterogeneous and complex metabolic disorder characterized by hyperglycemia secondary to either resistance to insulin actions on the liver and peripheral tissues, insufficient insulin secretion from pancreatic ß-cells, or both. An integrated balance between blood insulin levels and whole-body insulin sensitivity could theoretically provide the clinical effectiveness of insulin action. Peripheral blood insulin concentrations might be determined by the capacity of endogenous pancreatic ß-cell insulin secretion and the degree of the whole body insulin clearance. Here, we report a non-obese normoinsulinemic Japanese diabetic patient with elevated insulin clearance assessed by a hyperinsulinemic-euglycemic clamp examination and increased insulin secretion measured by daily urinary excretion of C-peptide immunoreactivity. We propose this unique pathogenic condition of diabetes with normoinsulinemia and elevated insulin clearance as "type 2 Japanese diabetes mellitus (T2JDM)."

Initial Acute Decline in Estimated Glomerular Filtration Rate After Sodium-Glucose Cotransporter-2 Inhibitor in Patients With Chronic Kidney Disease.

BACKGROUND: Renal function deterioration accompanied by an acute decrease in estimated glomerular filtration rate (eGFR) was observed early after starting sodium-glucose cotransporter-2 inhibitor (SGLT2i) therapy. It is unclear how much and how frequently the initial acute decline in eGFR (IAD-eGFR) would occur after SGLT2i administration, and the effects of IAD-eGFR on subsequent renal function are unknown in type 2 diabetes mellitus (T2DM) patients with chronic kidney disease (CKD). METHODS: We retrospectively recruited T2DM patients with CKD (stage 3b; 30 ≤ eGFR < 45 mL/min/1.73 m2) and who were newly treated with add-on SGLT2i. We further investigated the effects of SGLT2i therapy on eGFR early after starting treatment (1 - 3 months) and after 6 months of treatment. We examined the factors associated with a large IAD-eGFR (≥ 10%) using logistic regression analyses. RESULTS: Eighty-seven patients (male, 74.7%; mean age, 69.8 years; median hemoglobin A1c, 7.3%; mean eGFR, 37.8 mL/min/1.73 m2) were analyzed. The mean minimum eGFR early after SGLT2i administration was 34.9 mL/min/1.73 m2, which was significantly lower than before treatment (mean, -7.7%). Seventy patients (80.5%) had IAD-eGFR, and 36 patients (41.4%) had a large IAD-eGFR (≥ 10%). Overall, the mean eGFR was 38.2 at 6 months after starting SGLT2i administration. In patients with a large IAD-eGFR (≥ 10%), the eGFR decreased by 72.2% at 6 months to 35.5 mL/min/1.73 m2, showing a significant decline from the pretreatment value. In patients without a large IAD-eGFR, eGFR increased by 66.7% at 6 months to 40.0 mL/min/1.73 m2. Multiple logistic regression analysis showed that patients with a large IAD-eGFR had a significant association with a high estimated daily salt intake. CONCLUSIONS: SGLT2i treatment frequently induced a significant decrease in eGFR early after starting therapy, but eGFR tended to recover after 6 months in T2DM patients with CKD stage 3b. A large IAD-eGFR (≥ 10%) caused by SGLT2i may lead to subsequent deterioration in renal function, and it was significantly associated with a higher estimated daily salt intake. These results suggest that a more effective renoprotective therapeutic strategy using SGLT2i may be implemented by avoiding the occurrence of a large IAD-eGFR. Further prospective studies are warranted.

Characteristics of nephropathy in severely obese Japanese patients complicated with type 2 diabetes mellitus: a cross-sectional cohort study.

PURPOSE: We aimed to investigate the characteristics of kidney disease in severely obese Japanese patients with type 2 diabetes mellitus (T2DM). METHODS: This was a cross-sectional study of severely obese patients (body mass index ≥35 kg/m2) with T2DM treated at Jinnouchi Hospital, Kumamoto, Japan. RESULTS: A total of 3128 T2DM patients visited the hospital during the survey period, of whom 55 patients (1.7%) were severely obese and 50 patients were enrolled. In terms of diabetic nephropathy (DN), twenty-five patients were stage 1 (non-DN, 50.0%), sixteen were stage 2 (32.0%), five were stage 3 (10.0%), and four were stage 4 (8.0%). There were significant differences in the presence of urinary occult blood (P = 0.01) and history of cardiovascular disease (CVD) (P = 0.04) between patients with DN (stages 2-4) and those without DN (stage 1). The presence of urinary occult blood (odds ratio [OR], 4.96; 95% confidence interval, 1.32-18.6; P = 0.02) was significantly associated with the presence of DN according to multivariate logistic regression analysis with forced inclusion of age, sex, and CVD history. CONCLUSIONS: Urinary occult blood may be a significant independent factor associated with the presence of nephropathy in severely obese Japanese patients with T2DM. The presence of urinary occult blood could thus be an important pathogenic factor in obesity-related nephropathy in patients with T2DM.

Type 2 Diabetes Remission and Substantial Body Weight Reduction Achieved with Metformin and a Sodium-Glucose Cotransporter 2 Inhibitor.

The overall goal in the treatment of type 2 diabetes mellitus (T2DM) is remission. However, the effects of a sodium-glucose cotransporter 2 inhibitor (SGLT2i) on remission of T2DM are unknown. We herein report a case involving an overweight 43-year-old man who completely recovered from T2DM after SGLT2i therapy (dapagliflozin at 5 mg/day). In the pretreatment period, he had a body mass index (BMI) of 26.0 kg/m2, hemoglobin A1c (HbA1c) concentration of 10.3%, advanced insulin resistance, pancreatic ß-cell dysfunction, and fatty liver. Eighteen months after comprehensive therapy, including the administration of an SGLT2i and metformin, his BMI had decreased to 21.3 kg/m2 and his glycemic control was almost normal (HbA1c of 5.3%) despite discontinuation of all hypoglycemic medications. This report is the first to propose the usefulness of the combination therapy of SGLT2i and metformin for achieving normal body weight and remission of newly diagnosed T2DM in a real-world clinical situation.

Elevation of the renal threshold for glucose is associated with insulin resistance and higher glycated hemoglobin levels.

AIMS/INTRODUCTION: The renal threshold for glucose (RTg) corresponds to a blood glucose level of ~180 mg/dL; however, in hospitals, patients are often encountered who are hyperglycemic, but urine glucose test strip-negative, who remain negative for urine glucose even at blood glucose concentrations >180 mg/dL, implying a high RTg value. In this study, we aimed to identify factors determining high RTg in Japanese patients with type 2 diabetes mellitus. MATERIALS AND METHODS: We estimated RTg (eRTg) using urinalysis data from 67 type 2 diabetes mellitus patients for whom the glucose infusion rate (GIR) was determined by hyperinsulinemic-euglycemic clamp. After allocating patients to two groups according to their baseline eRTg (<180 mg/dL or ≥180 mg/dL), we identified the factors affecting eRTg using simple and multiple linear regression analyses. RESULTS: GIR, glycated hemoglobin (HbA1c), insulin use and dyslipidemia differed significantly between the groups. In simple regression analysis, GIR, HbA1c, body muscle-to-fat ratio and insulin use were significantly correlated with eRTg; and in multiple regression analysis, GIR and HbA1c remained independent negative and positive determinants, respectively, with the contribution of GIR being substantial. In receiver operating characteristic curve analysis, when GIR <5.7 was used as the insulin resistance threshold, the cut-off value of eRTg was 189 mg/dL (P = 0.0001). Furthermore, in receiver operating characteristic analysis using eRTg ≥189 mg/dL, the cut-off value for HbA1c was 8.0% (P = 0.0006). CONCLUSIONS: High eRTg is associated with low GIR and high HbA1c, with GIR making a substantial contribution.

Renoprotective Effects of Additional SGLT2 inhibitor Therapy in Patients With Type 2 Diabetes Mellitus and Chronic Kidney Disease Stages 3b-4: A Real World Report From A Japanese Specialized Diabetes Care Center.

BACKGROUND: Large randomized clinical trials of patients with type 2 diabetes mellitus (T2DM) and at high risk for cardiovascular disease revealed that sodium-glucose cotransporter 2 (SGLT2) inhibitors significantly reduced renal events. However, the trials included small numbers of patients with moderate-to-severe chronic kidney disease (CKD). Therefore, the renoprotective effects of SGLT2 inhibitors remain unknown in T2DM patients complicated with impaired renal function. We examined if SGLT2 inhibitors conferred beneficial effects on kidney function in T2DM patients with CKD. METHODS: We retrospectively recruited T2DM patients who were newly treated with add-on of SGLT2 inhibitors and suffered from moderate-to-severe renal impairment with CKD stages 3b-4 (15 < estimated glomerular filtration rate (eGFR) < 45 mL/min/1.73 m2), at initiation of SGLT2 inhibitor therapy. We analyzed T2DM patients with moderate-to-severe renal impairment who continued to use SGLT2 inhibitors for at least 1 year. We investigated the effects of SGLT2 inhibitor therapy on 1-year changes in eGFR and urinary protein excretion before and after the treatment. RESULTS: We analyzed 42 T2DM patients with median eGFR of 40.4 mL/min/1.73 m2. One-year SGLT2 inhibitor therapy lowered median hemoglobin A1c (HbA1c) levels from 7.6% to 7.5% (not significant). Body weight and blood pressure were significantly decreased, and hemoglobin was significantly increased. The median value of eGFR after 1 year of SGLT2 inhibitor therapy was 41.0 mL/min/1.73 m2, with no significant difference compared with baseline. The annual decline in eGFR improved significantly after SGLT2 inhibitor therapy (eGFR: (median), pre: -3.8, vs. post: 0.1 mL/min/1.73 m2 per year, P < 0.01). We also found a significant decrease in urinary protein excretion after SGLT2 inhibitor therapy (urinary protein-to-creatinine ratio: (median), pre: 0.36, vs. post: 0.23 g/g creatinine, n = 35, P < 0.01). CONCLUSIONS: This study revealed the promising observations that add-on treatment with SGLT2 inhibitors exerted significant renoprotective effects, culminating in improvements in annual decline in eGFR and urinary protein excretion in T2DM patients with CKD stages 3b-4, but did not significantly reduce HbA1c. Further prospective clinical trials are warranted to fully elucidate the effects of SGLT2 inhibitors on glycemic control and renal function in T2DM patients with moderate-to-severe renal impairment.

Impact of Dapagliflozin Therapy on Renal Protection and Kidney Morphology in Patients With Uncontrolled Type 2 Diabetes Mellitus.

BACKGROUND: We examined whether the sodium-glucose cotransporter-2 inhibitor (SGLT2i) dapagliflozin can improve urine albumin-to-creatinine ratio (UACR) associated with a reduction in body weight or body fat in patients with type 2 diabetes mellitus (T2DM). METHODS: We prospectively recruited T2DM patients having inadequate glycemic control (hemoglobin A1c (HbA1c) > 7.0%) not on SGLT2i therapy. We treated the patients with add-on dapagliflozin treatment or intensification of non-SGLT2 inhibitor therapies for 6 months. We measured UACR, urine N-acetyl-ß-glucosaminidase (uNAG), and body composition including total body fat mass (TBFM) as assessed by bioelectrical impedance analysis. We also investigated changes in length and radiation attenuation properties of the kidneys and abdominal fat area using computed tomography. RESULTS: We enrolled 62 patients with a mean HbA1c of 8.0%. The HbA1c and fasting blood glucose were significantly decreased in both the dapagliflozin-group and non-SGLT2i-group, with no significant difference between the two groups. Dapagliflozin treatment, but not non-SGLT2i treatment, significantly decreased UACR and uNAG. The changes in UACR and uNAG were significantly greater in the dapagliflozin group compared with the non-SGLT2i group. Dapagliflozin treatment, but not non-SGLT2i treatment, significantly decreased the body weight, TBFM, and abdominal fat area and significantly increased kidney length and radiation attenuation. The percentage change in UACR was significantly correlated with changes in TBFM, but not with body weight. By multivariate logistic regression analysis, dapagliflozin treatment was significantly associated with the improvement of UACR. CONCLUSIONS: Add-on treatment with dapagliflozin exhibited significant renoprotective effects, with improvement of UACR and uNAG and increased kidney length and radiation attenuation in patients with uncontrolled T2DM.

The SGLT2 Inhibitor Dapagliflozin Significantly Improves the Peripheral Microvascular Endothelial Function in Patients with Uncontrolled Type 2 Diabetes Mellitus.

Objective Sodium-glucose co-transporter 2 (SGLT2) inhibitors reduce cardiovascular events and decrease the body fat mass in patients with type 2 diabetes mellitus (T2DM). We examined whether or not the SGLT2-inhibitor dapagliflozin can improve the endothelial function associated with a reduction in abdominal fat mass. Methods We prospectively recruited patients with uncontrolled [hemoglobin A1c (HbA1c) >7.0%] T2DM who were not being treated by SGLT2 inhibitors. Patients were treated with add-on dapagliflozin (5 mg/day) or non-SGLT2 inhibitor medicines for 6 months to improve their HbA1c. We measured the peripheral microvascular endothelial function as assessed by reactive hyperemia peripheral arterial tonometry (RH-PAT) and calculated the natural logarithmic transformed value of the RH-PAT index (LnRHI). We then investigated changes in the LnRHI and abdominal fat area using computed tomography (CT). Results The subjects were 54 patients with uncontrolled T2DM (72.2% men) with a mean HbA1c of 8.1%. The HbA1c was significantly decreased in both groups, with no significant difference between the groups. Dapagliflozin treatment, but not non-SGLT2 inhibitor treatment, significantly increased the LnRHI. The changes in the LnRHI were significantly greater in the dapagliflozin group than in the non-SGLT2 inhibitor group. Dapagliflozin treatment, but not non-SGLT2 inhibitor treatment, significantly decreased the abdominal visceral fat area, subcutaneous fat area (SFA), and total fat area (TFA) as assessed by CT and significantly increased the plasma adiponectin levels. The percentage changes in the LnRHI were significantly correlated with changes in the SFA, TFA, systolic blood pressure, and adiponectin. Conclusion Add-on treatment with dapagliflozin significantly improves the glycemic control and endothelial function associated with a reduction in the abdominal fat mass in patients with uncontrolled T2DM.

Dapagliflozin Reduces Fat Mass without Affecting Muscle Mass in Type 2 Diabetes.

AIM: Sodium-glucose co-transporter 2 inhibitor (SGLT2i) therapy has been demonstrated to improve glycemic control and reduce body weight and fat mass in type 2 diabetes mellitus (T2DM). Here, our aim was to investigate the effects of SGLT2i dapagliflozin-treatment on body muscle mass and muscle fat content in patients with T2DM. METHODS: We prospectively recruited uncontrolled (hemoglobin A1c [HbA1c] ＞7%) Japanese T2DM patients who had a body mass index (BMI) ＜35 kg/m2. Patients were treated with dapagliflozin (5 mg/day) or non-SGLT2i medicines for six months to improve HbA1c. We investigated changes in body composition using bioelectrical impedance analysis and changes in psoas muscle mass using abdominal computed tomography (CT). RESULTS: Subjects were 50 T2DM patients (72% male) with a mean age of 56.1 years, mean BMI of 27.1 kg/m2 and mean HbA1c of 7.9%. HbA1c, body weight, and BMI were significantly decreased in both treatment groups, and the HbA1c decrease was not significantly different between groups. Dapagliflozin treatment significantly decreased body weight and total fat mass without affecting skeletal muscle mass. The absolute change in soft lean mass and skeletal muscle mass was not significantly different between groups. Dapagliflozin treatment did not significantly decrease psoas muscle index, and the absolute change in this index was not significantly different between groups. Dapagliflozin therapy also produced a significant increase in CT radiation attenuation in the third lumbar paraspinal muscles compared with non-SGLT2i therapy. CONCLUSIONS: Treatment with dapagliflozin for six months significantly improved glycemic control and reduced body weight without reducing muscle mass in T2DM patients.

Clinical Factors Associated with Initial Decrease in Body-Fat Percentage Induced by Add-on Sodium-Glucose Co-transporter 2 Inhibitors in Patient with Type 2 Diabetes Mellitus.

BACKGROUND AND OBJECTIVE: Obesity is globally recognized as an important clinical problem and sodium-glucose co-transporter 2 (SGLT2) inhibitors are considered a suitable therapy for obese patients with type 2 diabetes mellitus (T2DM). We examined the clinical factors associated with initial decrease in body-fat percentage (Fat %) induced by SGLT2 inhibitors in patients with T2DM. METHODS: We retrospectively enrolled patients newly treated with SGLT2 inhibitors in addition to ongoing medications at Jinnouchi Hospital between April 2014 and December 2015. We examined the SGLT2 inhibitor-induced change in body composition by using a bioelectrical impedance analyzer (InBody770®) before SGLT2 inhibitor administration and after 4 weeks' treatment. RESULTS: A total of 175 patients with T2DM were enrolled and we analyzed 148 patients. Add-on SGLT2 inhibitor treatment significantly reduced body weight (- 1.04 ± 1.18 kg, p < 0.01), total fat quantity (- 0.62 ± 1.19 kg, p < 0.01), and Fat % (- 0.4 ± 1.4%, p < 0.01). Pretreatment levels of glycated hemoglobin (HbA1c) [odds ratio (OR), 1.61; 95% confidence interval (CI), 1.15-2.25, p < 0.01] and smoking (OR, 2.65; 95% CI, 1.14-6.15, p = 0.02) were significantly associated factors for greater fat-reduction defined as more than 0.4% (median) decrease in Fat % in multivariate logistic regression analysis. In receiver operator characteristic analysis, the cut-off value of pretreatment levels of HbA1c for a greater Fat % decrease was 7.7% (sensitivity 53% and specificity 69%, p < 0.01). CONCLUSION: Additional treatment with SGLT2 inhibitors effectively decreased Fat % in T2DM patients with high HbA1c levels before SGLT2 inhibitor administration. Our results suggest a greater initial response in Fat % reduction to SGLT2 inhibitor therapy in diabetic patients with pretreatment HbA1c levels ≥ 7.7%.

Impaired hepatic granuloma formation in mice deficient in C-C chemokine receptor 2.

Granulomas are characterized histologically by a nodular collection of macrophages with occasional admixture of epithelioid cells, multinucleate giant cells, and other immunocompetent cells. Chemokines are considered to play an important role in the recruitment of these constituent cells of granulomas. The present study has examined the effect of a deficiency of C-C chemokine receptor-2 (CCR2) on hepatic granuloma formation induced by a single injection of Zymosan A. In CCR2+/+ mice, the number and the size of granulomas gradually increased until they reached peak values at 10 days after the injection. In contrast, both the number and the size of granulomas were smaller in CCR2-/- mice than in CCR2+/+ mice from days 5 to 21. They showed low peaks at day 5, after which the number and the size of the granulomas gradually decreased. Immunohistochemical analysis of the constituent granuloma cells using cell type-specific monoclonal antibodies revealed rapid accumulation of blood monocytes, with subsequent differentiation to macrophages, in CCR2+/+ mice during days 2-10. This process was greatly impaired in CCR2-/- mice and granulomas remained small. At all time points, the percentage of polymorphonuclear cells in granulomas was higher in CCR2-/- mice than in CCR2+/+ mice. Interestingly, multinucleate giant cells were frequently observed in granulomas in CCR2-/- mice, whereas they rarely appeared in CCR2+/+ mice. Profiles of liver cytokine RNA levels as well as serum cytokine levels revealed reduced expression of the Th1 cytokine IFN-gamma in CCR2-/- mice. These data clearly indicate that signalling through CCR2 has many effects on the normal growth and development of hepatic granulomas.

Production, characterization, and interspecies reactivities of monoclonal antibodies against human class A macrophage scavenger receptors.

Class A macrophage scavenger receptor (SR-A) is one of the major receptors of macrophages and plays important roles in atherogenesis and host defense mechanisms. To assess the role of SR-A, monoclonal antibodies were generated by immunizing SR-A-deficient mice with a recombinant protein of human type I SR-A as immunogen. Four antibodies (SRA-C6, SRA-D10, SRA-E5, and SRA-F8) were confirmed to be specific for SR-A by Western blot analysis. In early atherosclerotic lesions, these antibodies recognized scattered macrophages in intima and foamy macrophages in the periphery of atheromatous cores. Interestingly, foamy macrophages in the core lesion were only weakly stained. In other organs, the antibodies recognized tissue macrophages such as alveolar macrophages, Kupffer cells in the liver, red pulp macrophages in the spleen, sinus macrophages in lymph nodes, and interstitial macrophages in various organs. Perivascular macrophages in the brain (Mato cells) were also positive for these antibodies. Freshly isolated blood monocytes were negative; however, they became positive for these antibodies after 1 day in culture. At 3-5 days in culture, the reaction intensity became stronger along their differentiation towards macrophages. Dendritic cells such as interdigitating cells of lymphoid tissues and epidermal Langerhans cells were invariably negative. In the reaction with animal tissues, each antibody showed a unique reaction pattern. Among four antibodies, SRA-E5 recognized SR-A molecules in all animal species examined, including rats and mice. These antibodies will be useful tools for the study of SR-A in atherogenesis and various other pathological conditions in humans and animal species.