[Spontaneous regression of HIV-associated EBV-positive mucocutaneous ulcer due to immune reconstruction with antiretroviral therapy].

A 24-year-old man was found to have an ileocecal ulcer by colonoscopy. A pathological diagnosis of diffuse large B-cell lymphoma (DLBCL) with diffuse positive reaction of Epstein-Barr encoding region (EBER) by in situ hybridization was made based on analysis of the specimen. Acquired immunodeficiency syndrome (AIDS) complicated by pneumocystis jirovecii pneumonia was also diagnosed. As no other significant lymphomatous lesions were identified by further examination, a clinical diagnosis of EBV-positive mucocutaneous ulcer (EBVMCU) was made. Rather than performing systemic chemotherapy, the lesion was closely monitored and antiretroviral therapy (ART) for AIDS was started with the hope of treating the lesion through immune reconstitution. The lesion had completely disappeared by day 79 after starting ART, and has not recurred for over 3 years. EBVMCU is known to develop secondary to various immunosuppressive states including AIDS. Here we report a rare case of EBVMCU detected at diagnosis of AIDS that entered complete remission after immune reconstitution by ART.

Cardiovascular risk factors are associated with augmented thrombogenicity in healthy individuals: analysis using the Total Thrombus-formation Analysis System.

BACKGROUND: Rupture of an atherosclerotic plaque and subsequent exposure of the subendothelial prothrombotic matrix to blood cause arterial thrombosis. Circulating platelets play an indispensable role in the growth of arterial thrombi partially owing to their unique ability to adhere to the subendothelial matrix and to aggregate to each other under flow conditions. Recently, the Total Thrombus-formation Analysis System (T-TAS) was developed for ex vivo analysis of the thrombogenic potential of whole blood samples under flow conditions. Despite the potential clinical utility of the T-TAS in assessing the risk for thrombosis and bleeding, reference intervals for T-TAS analysis in healthy individuals have not been determined. METHODS: In total, 122 whole blood samples were collected from healthy volunteers ranging in age from 25 to 45 years. T-TAS analysis and hematological, physiological, and lifestyle assessments were conducted in these subjects. Whole blood samples anticoagulated with hirudin were perfused into a collagen-coated microchip (PL chip). The time to 10 kPa and the area under the flow pressure curve up to 10 min (AUC10) were analyzed as representative variables for thrombogenic potential. Reference intervals, which were defined as 2.5-97.5 percentiles, were determined. Additionally, univariate and multivariate analyses were performed to identify factors associated with the AUC10 in the T-TAS. RESULTS: The time to 10 kPa and the AUC10 widely varied, even in healthy volunteers. The reference intervals were 1.50-4.02 min and 223.4-456.8, respectively, at a shear rate of 1500 s- 1. Univariate and multivariate analyses showed that platelet counts were most significantly associated with the AUC10 of the T-TAS. The presence of one or more cardiovascular risk factors of a high body mass index, a high pulse pressure, high fasting serum glucose levels, high low-density lipoprotein-cholesterol levels, a history of smoking, and no habitual exercise, had the second largest effect on the AUC10 of the T-TAS. CONCLUSIONS: Healthy volunteers who had any cardiovascular risk factors showed augmented thrombogenicity, even in artificial uniform capillaries, compared with those without any risk factors in the T-TAS.

Evaluation of VEGF-A in platelet and microRNA-126 in serum after coronary artery bypass grafting.

Platelet functions are thought to contribute to clinical outcomes after heart surgery. This study was conducted to assess the pivotal roles of vascular endothelial growth factor-A (VEGF-A) and microRNA-126 (miR-126) during coronary artery bypass grafting (CABG). Whole blood was collected for platelet isolation from 67 patients who underwent CABG surgery between July 2013 and March 2014. VEGF-A and miR-126 levels in serum, plasma, and platelets were measured at various time points and compared with clinical characteristics. The platelet count was decreased at 3 days after CABG. This dynamic change in platelet count was larger after conventional coronary artery bypass (CCAB) than off-pump coronary artery bypass (OPCAB). VEGF-A in the same number of platelets (IP-VEGF-A) was increased at 3 days after CABG, followed by an increase of VEGF-A in serum (S-VEGF-A) at 7 days after surgery. The miR-126-3p level in serum (S-miR-126-3p) increased rapidly after CABG and then decreased below preoperative levels. The IP-VEGF-A level on day 7 after CABG in patients with peripheral artery disease (PAD), who suffered from endothelial dysfunction, was higher compared with patients without PAD. Conversely, S-miR-126-3p on day 7 after surgery was lower in patients with PAD than in patients without PAD. Low levels of S-miR-126-3p due to endothelial dysfunction may lead to high IP-VEGF-A, which is closely related to complications after CABG.

Successful treatment of an AIDS patient with prolonged Mycobacterium avium bacteremia, high HIV RNA, HBV infection, Kaposi's sarcoma and cytomegalovirus retinitis.

We report an AIDS patient with a high HIV RNA copy number in the plasma who was successfully treated for prolonged Mycobacterium avium bacteremia and other complications. An HIV-infected patient with high fever, anemia, high alkaline phosphatase, cystic lung lesions, hepatitis B virus infection and Kaposi's sarcoma was referred to our hospital. PCR of the blood revealed Mycobacterium avium bacteremia and the time to blood culture positivity was 8 days. The HIV-1 RNA copy number in the plasma was more than ten million copies/ml and the CD4-positive T cell count was 21 cells/µL. Although the high fever resolved five days after therapy for Mycobacterium avium was started, the fever recurred just before starting anti-retroviral therapy (ART) including dolutegravir. The patient experienced repeated but self-limiting bouts of severe inflammation. Mycobacteremia was intermittently detected up to 79 days, suggesting that the recurrent episodes of inflammation were due to the intermittent dissemination of mycobacteria, and that persistent treatment is needed. Five months after the beginning of ART, the HIV-1 RNA copy number in the plasma was still 28,000 copies/ml. An HIV drug-resistance test revealed sensitivity to all anti-retroviral drugs. Eleven months after the initiation of ART, the HIV RNA copy number in the plasma decreased to 45 copies/mL and the CD4-positive T cell count recovered to 205 cells/µL. Our case also suggests that dolutegravir can be effective in cases with prolonged high levels of HIV RNA. Our findings emphasize that prompt diagnosis and persistent therapy for mycobacterial infection are important for successful treatment.

Legionella pneumophila infection-mediated regulation of RICTOR via miR-218 in U937 macrophage cells.

BACKGROUND: Inhalation of aerosolized Legionella pneumophila, a Gram-negative bacterium, can cause severe pneumonia. During infection, L. pneumophila replicates intracellularly in macrophages. The involvement of host microRNAs (miRNAs) in L. pneumophila infection is not fully understood. METHODS: The human macrophage-like cell line U937 was infected with L. pneumophila. The levels of miRNA and messenger RNA (mRNA) were measured using reverse transcriptase polymerase chain reaction. Release of lactate dehydrogenase was used to evaluate cytotoxicity. The expression of RICTOR and related proteins was examined by western blotting of cell lysates. RESULTS: L. pneumophila infection upregulated the expression of miR-218 and the host genes SLIT2 and SLIT3 in U937 cells. The expression of RICTOR, a component of the mechanistic target of rapamycin complex 2 (mTORC2), decreased during L. pneumophila infection. RICTOR protein expression was inhibited by the overexpression of miR-218, whereas knockdown of miR-218 restored the downregulation of RICTOR by L. pneumophila. L. pneumophila infection induced the expression of the proinflammatory cytokines IL-6 and TNF-alpha, which was modulated by knockdown of miR-218 or RICTOR. CONCLUSIONS: Our study revealed the involvement of miR-218 in regulating the inflammatory response of macrophages against L. pneumophila infection. These findings suggest potential novel roles for miR-218 and RICTOR as therapeutic targets of L. pneumophila infection.

High-fat diet exacerbates imiquimod-induced psoriasis-like dermatitis in mice.

Psoriasis, a chronic inflammatory skin disease, is closely related to systemic metabolism. An elevated body mass index (BMI) is a risk factor for psoriasis; inflammasomes are activated by adipose tissue macrophages in obese subjects. We hypothesized that hyperlipidaemia is involved in the pathogenesis of psoriasis and examined the role of a high-fat diet (HFD) in the development of psoriasis in imiquimod (IMQ)-treated mice. The body weight and serum level of cholesterol were significantly higher in mice fed an HFD than in a regular diet (RD). HFD mice had higher psoriasis skin scores, and the number of neutrophils infiltrating into the lesional skin was elevated. IL-17A mRNA expression was significantly increased in the skin of IMQ-treated HFD mice; the expression of IL-22, IL-23 and TNF-α mRNA was not enhanced. Caspase-1 and IL-1ß were activated in the skin of IMQ-treated HFD mice, and their serum level of IL-17A, TNF-α and IL-1ß was significantly upregulated. Our findings strongly suggest that hyperlipidaemia is involved in the development and progression of psoriasis via systemic inflammation and inflammasome activation.

Recovery of Endothelial Function after Minor-to-Moderate Surgery Is Impaired by Diabetes Mellitus, Obesity, Hyperuricemia and Sevoflurane-Based Anesthesia.

Endothelial dysfunction is observed in several cardiovascular diseases, where endothelium-dependent vasodilation is impaired by oxidative stress. However, the time course of endothelial function during the perioperative period of a minor-to-moderate surgery, and the effects of atherosclerotic risk factors and employed general anesthetics on recovery of endothelial function, are unknown. Endothelial function of 30 patients was evaluated as the reactive hyperemia index (RHI) of reactive hyperemia peripheral arterial tonometry. RHI was measured on day before surgery (control), immediately after surgery (Day 0), day after surgery (Day 1), and day 4 after surgery (Day 4) in patients with no functional limitations who were scheduled for oral and maxillofacial surgery of around 3 hours. Sevoflurane- or propofol-based anesthesia supplemented with an opioid analgesic remifentanil was employed. The control RHI was 2.26 ± 0.64. The RHI significantly decreased to the lowest level on Day 0 (1.52 ± 0.28), recovered on Day 1 (2.07 ± 0.58), and improved further on Day 4 (2.55 ± 0.83). Multiple linear regression analysis revealed that recovery of the RHI from Day 0 to Day 4 was impaired by diabetes mellitus (P = 0.0313), obesity (BMI ≥ 25; P = 0.0166), hyperuricemia (uric acid ≥ 6.0 mg/dL; P = 0.0416) and sevoflurane-based anesthesia (P = 0.0308). These findings suggest that endothelial function as evaluated by the RHI is severely suppressed on the day of a minor-to-moderate surgery, and that it improves until the 4th postoperative day on average. Recovery of endothelial function is impaired by diabetes mellitus, obesity, hyperuricemia, and sevoflurane-based anesthesia.

Low grade inflammation inhibits VEGF induced HUVECs migration in p53 dependent manner.

In the course of studying crosstalk between inflammation and angiogenesis, high doses of pro-inflammatory factors have been reported to induce apoptosis in cells. Under normal circumstances also the pro-inflammatory cytokines are being released in low doses and are actively involved in cell signaling pathways. We studied the effects of low grade inflammation in growth factor induced angiogenesis using tumor necrosis factor alfa (TNFα) and vascular endothelial growth factor A (VEGF) respectively. We found that low dose of TNFα can inhibit VEGF induced angiogenesis in human umbilical vein endothelial cells (HUVECs). Low dose of TNFα induces mild upregulation and moreover nuclear localization of tumor suppressor protein 53 (P53) which causes decrease in inhibitor of DNA binding-1 (Id1) expression and shuttling to the cytoplasm. In absence of Id1, HUVECs fail to upregulate ß3-integrin and cell migration is decreased. Connecting low dose of TNFα induced p53 to ß3-integrin through Id1, we present additional link in cross talk between inflammation and angiogenesis.

PERMEABILITY AND ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR EFFECTS OF BEVACIZUMAB, RANIBIZUMAB, AND AFLIBERCEPT IN POLARIZED RETINAL PIGMENT EPITHELIAL LAYER IN VITRO.

PURPOSE: To determine the effects of bevacizumab, ranibizumab, and aflibercept on the permeability and the effects of anti-vascular endothelial growth factor (VEGF) on highly polarized retinal pigment epithelial cells (RPECs) in vitro. METHODS: Highly polarized RPECs were cultured in the upper chamber of a Transwell system. Anti-VEGF antibodies were added to the upper chamber, and the concentrations of the drugs in the lower chambers were measured. The permeability rates of the three anti-VEGF drugs through the RPEC layer and the concentration of VEGF in each chamber were determined. RESULTS: The permeability of aflibercept was significantly lower by about 40% than that of bevacizumab through the RPEC layer (P < 0.05). Ranibizumab was significantly more permeable through the RPECs than bevacizumab (180% of bevacizumab, P < 0.05). Although VEGF was almost absent in the upper chamber after exposure to the 3 antibodies, it was decreased more significantly with aflibercept than with bevacizumab in the lower chamber (2.8% vs. 65.8% of control; P < 0.01). Ranibizumab also decreased the VEGF level compared with bevacizumab (31.7% vs. 65.8% of control; P < 0.01). CONCLUSION: The greater reduction of the amount of VEGF in the lower chamber by aflibercept and ranibizumab than bevacizumab may explain why aflibercept and ranibizumab are more effective than bevacizumab against type 1 choroidal neovascularization.

Basic concept for evaluating coagulation and fibrinolysis data.

"Fibrin is insoluble in blood" is the most important concept to accept the coagulation system. Essentially, blood coagulation is a process to convert blood from soluble to insoluble. Fibrinolysis is another process to convert insoluble protein to soluble protein again. The blood coagulation cascade requires calcium ion and efficiently acts on platelet phospholipid membranes. On the other hand, the fibrinolysis system efficiently acts on fibrin. Unlike other vitamin K-dependent coagulation factors, thrombin can be released from the coagulation site to the systemic circulation and has multiple biological effects regulated through thrombin receptors. Thrombin is captured by thrombomodulin on endothelial cells or anti-thrombin. Low level of coagulation and fibrinolysis idling are always working even under healthy conditions because of shear stress on injured vessels. Measurement of coagulation times, such as PT and APTT, is the basic method used by numerous clinics in coagulation-related examinations. Measurement of coagulation factor activity by one method is based on the concept that excess amounts of coagulation factors circulate in the blood. Under DIC conditions, excess pathological protease activity yields a huge amount of peptides in the blood in addition to coagulation and fibrinolysis markers.

[Harmonization of TSH Measurements.]

The measured concentration of thyroid stimulating hormone (TSH) differs depending on the reagents used. Harmonization of TSH is crucial because the decision limits are described in current clinical practice guide- lines as absolute values, e.g. 2.5 mIU/L in early pregnancy. In this study, we tried to harmonize the report- ed concentrations of TSH using the all-procedure trimmed mean. TSH was measured in 146 serum samples, with values ranging from 0.01 to 18.8 mIU/L, using 4 immunoassays. The concentration of TSH was highest with E test TOSOH and lowest with LUMIPULSE. The concentrations with each reagent were recalculated with the following formulas: E test TOSOH 0.855x-0.014; ECLusys 0.993x+0.079; ARCHITECT 1.041x- 0.010; and LUMIPULSE 1.096x-0.015. Recalculation eliminated the between-assay discrepancy. These formulas may be used until harmonization of TSH is achieved by the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC).

Coffee bean polyphenols ameliorate postprandial endothelial dysfunction in healthy male adults.

To reveal the effect of coffee bean polyphenols (CBPs) on blood vessels, this study aimed to investigate the effect of CBPs on acute postprandial endothelial dysfunction. Thirteen healthy non-diabetic men (mean age, 44.9 ± 1.4 years) consumed a test beverage (active: containing CBPs, placebo: no CBPs) before a 554-kcal test meal containing 14 g of protein, 30 g of fat and 58 g of carbohydrates. Then, a crossover analysis was performed to investigate the time-dependent changes in flow-mediated dilation (FMD) in the brachial artery. In the active group, the postprandial impairment of FMD was significantly improved, the two-hour postprandial nitric oxide metabolite levels were significantly increased and the six-hour postprandial urinary 8-epi-prostaglandin F2α levels were significantly reduced compared to the placebo group. The test meal increased the levels of blood glucose, insulin and triglycerides in both groups with no significant intergroup differences. These findings indicate that CBPs intake ameliorates postprandial endothelial dysfunction in healthy men.

Toxic effects of extracellular histones and their neutralization by vitreous in retinal detachment.

Histones are DNA-binding proteins and are involved in chromatin remodeling and regulation of gene expression. Histones can be released after tissue injuries, and the extracellular histones cause cellular damage and organ dysfunction. Regardless of their clinical significance, the role and relevance of histones in ocular diseases are unknown. We studied the role of histones in eyes with retinal detachment (RD). Vitreous samples were collected during vitrectomy, and the concentration of histone H3 was measured by enzyme-linked immunosorbent assay. The location of the histones and related molecules was examined in a rat RD model. The release of histones and their effects on rat retinal progenitor cells R28 and ARPE-19 were evaluated in vitro. In addition, the protective role of the vitreous body against histones was tested. The intravitreal concentration of histones was higher in eyes with RD (mean, 30.9 ± 9.8 ng/ml) than in control eyes (below the limit of detection, P<0.05). In the rat RD model, histone H3 was observed on the outer side of the detached retina and was associated with photoreceptor death. Histone H3 was released from cultured R28 by oxidative stress. Histones at a concentration 10 µg/ml induced the production of interleukin-8 in ARPE-19 cells (2.5-fold increase, P<0.05) that was mediated through the ERK1/2- and p38 MAPK-dependent pathways and Toll-like receptor 4. Histones were toxic to cells at concentrations of ≥ 20 µg/ml. Vitreous body or hyaluronan decreased toxicity of histones by inhibiting diffusion of histones. These results indicate that histones are released from retinas with RD and may modulate the subretinal microenvironment by functioning as damage-associated molecular pattern molecules, thereby inducing proinflammatory cytokines or cell toxicity. In addition, the important role of the vitreous body and hyaluronan in protecting the retina from these toxic effects is suggested.

Exacerbation of microcytic anemia associated with cessation of anti-retroviral therapy in an HIV-1-infected patient with beta thalassemia.

We report a patient with Japanese minor ß thalassemia and HIV-1 infection. The patient showed prolonged anemia, which was originally attributed to chronic parvovirus B19 infection. Twelve years later, the patient presented with exacerbation of microcytic anemia following cessation of anti-retroviral therapy; the exacerbation resolved when anti-retroviral therapy was resumed. Sequencing of the ß globin gene revealed heterozygosity for a four-nucleotides deletion at codon 41/42 and minor ß thalassemia was confirmed. Because HIV-1-infected patients frequently show anemia due to nutritional deficiencies, opportunistic infections, AIDS-related malignancies, drug treatment and a direct effect of HIV-1 on the bone marrow, it is likely to overlook other causes of anemia. Thalassemia should be considered in the differential diagnosis of anemia even in HIV-1 infected patients, when microcytic anemia without iron deficiency is observed. Our case suggested that active HIV infection may have worsened ß thalassemia, and early introduction of anti-retroviral therapy is beneficial for the recovery of anemia.

Neutrophil-Derived MicroRNA-1290 Promotes Keratinocyte Proliferation in Psoriasis.

The pathological hallmark of psoriasis is the infiltration of neutrophils into the skin. Some neutrophil-derived microRNAs (miRNAs) serve as biomarkers for various diseases, but none have been reported for psoriasis. In this study, we investigated the involvement of miRNAs released from neutrophils in psoriasis pathogenesis. We compared the expression of miRNAs in the sera of patients with psoriasis with that in healthy individuals and found that the expression of 2 miRNAs-miR-223 and miR-1290-was significantly upregulated in the sera of patients with psoriasis. The serum levels of these miRNAs positively correlated with the PASI and CRP levels. We used all-trans retinoic acid to induce the differentiation of human promyelocytic leukemia HL-60 cells into neutrophil-like cells and found that the release of both miRNAs increased during differentiation. Furthermore, the release of miR-1290 was increased by TNF-α in neutrophil-like cells and human neutrophils. Treatment with the miR-1290 precursor promoted the proliferation of human keratinocytes, increased the proportion of S-phase cells, and upregulated the phosphorylation of extracellular signal-regulated kinase 1/2. These results suggest that miR-1290 plays a vital role in regulating neutrophil differentiation and keratinocyte proliferation and could be a serum marker of psoriasis severity.

Saturated fatty acid palmitate induces extracellular release of histone H3: a possible mechanistic basis for high-fat diet-induced inflammation and thrombosis.

Chronic low-grade inflammation is a key contributor to high-fat diet (HFD)-related diseases, such as type 2 diabetes, non-alcoholic steatohepatitis, and atherosclerosis. The inflammation is characterized by infiltration of inflammatory cells, particularly macrophages, into obese adipose tissue. However, the molecular mechanisms by which a HFD induces low-grade inflammation are poorly understood. Here, we show that histone H3, a major protein component of chromatin, is released into the extracellular space when mice are fed a HFD or macrophages are stimulated with the saturated fatty acid palmitate. In a murine macrophage cell line, RAW 264.7, palmitate activated reactive oxygen species (ROS) production and JNK signaling. Inhibitors of these pathways dampened palmitate-induced histone H3 release, suggesting that the extracellular release of histone H3 was mediated, in part, through ROS and JNK signaling. Extracellular histone activated endothelial cells to express the adhesion molecules ICAM-1 and VCAM-1 and the procoagulant molecule tissue factor, which are known to contribute to inflammatory cell recruitment and thrombosis. These results suggest the possible contribution of extracellular histone to the pathogenesis of HFD-induced inflammation and thrombosis.

Verification of the relationship between the sequential organ failure assessment score and the length of intensive care unit and hospital stay in terms of medical resources input.

This study aimed to clarify the relationship between the sequential organ failure assessment (SOFA) score and the length of intensive care unit (ICU) and hospital stays and verify whether the SOFA score can indicate the optimal length of ICU stay. Medical resource input was evaluated as the medical treatment score, converted by volume, within 2 days after ICU admission. After classifying emergency patients into surgical and nonsurgical categories, the relationship between medical resources, SOFA score, and ICU and hospital stay lengths was analyzed. Medical resource input was high when the SOFA score was high after ICU admission. A positive correlation was confirmed between the SOFA score and length of ICU stay in surgical and nonsurgical patients. Nonsurgical patients are more likely to be discharged within the diagnosis procedure combination hospital stages I and II if medical resources are high in the initial stages of ICU admission. The SOFA score affects medical resource input and the length of ICU stay. The early input of medical resources after ICU admission reduces the length of hospital stay in the diagnosis procedure combination, suggesting that the SOFA score is a valuable indicator of the optimal length of ICU stay.

Anti-ganglionic acetylcholine receptor antibodies in functional neurological symptom disorder/conversion disorder.

Objective: Autoimmune autonomic ganglionopathy (AAG) is a rare disorder characterized by autonomic failure associated with the presence of anti-ganglionic acetylcholine receptor (gAChR) antibodies; however, several studies have reported that individuals with anti-gAChR antibodies present with central nervous system (CNS) symptoms such as impaired consciousness and seizures. In the present study, we investigated whether the presence of serum anti-gAChR antibodies correlated with autonomic symptoms in patients with functional neurological symptom disorder/conversion disorder (FNSD/CD). Methods: Clinical data were collected for 59 patients presenting with neurologically unexplained motor and sensory symptoms at the Department of Neurology and Geriatrics between January 2013 and October 2017 and who were ultimately diagnosed with FNSD/CD according to the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition. Correlations between serum anti-gAChR antibodies and clinical symptoms and laboratory data were analyzed. Data analysis was conducted in 2021. Results: Of the 59 patients with FNSD/CD, 52 (88.1%) exhibited autonomic disturbances and 16 (27.1%) were positive for serum anti-gAChR antibodies. Cardiovascular autonomic dysfunction, including orthostatic hypotension, was significantly more prevalent (75.0 vs. 34.9%, P = 0.008), whereas involuntary movements were significantly less prevalent (31.3 vs. 69.8%, P = 0.007), among anti-gAChR antibody-positive compared with -negative patients. Anti-gAChR antibody serostatus did not correlate significantly with the frequency of other autonomic, sensory, or motor symptoms analyzed. Conclusions: An autoimmune mechanism mediated by anti-gAChR antibodies may be involved in disease etiology in a subgroup of FNSD/CD patients.

VEGF-A165 is the predominant VEGF-A isoform in platelets, while VEGF-A121 is abundant in serum and plasma from healthy individuals.

Vascular endothelial growth factor A (VEGF-A) plays pivotal roles in regulating tumor angiogenesis as well as physiological vascular function. The major VEGF-A isoforms, VEGF-A121 and VEGF-A165, in serum, plasma, and platelets have not been exactly evaluated due to the lack of the appropriate assay system. Antibodies against human VEGF-A121 and VEGF-A165 (hVEGF-A121 and hVEGF-A165) were successfully produced and Enzyme-Linked ImmunoSorbent Assay (ELISA) for hVEGF-A121 and hVEGF-A165 were separately created by these monoclonal antibodies. The measurement of recombinant hVEGF-A121 and hVEGF-A165 by the created ELISA showed no cross-reaction between hVEGF-A121 and hVEGF-A165 in conditioned media from HEK293 cells transfected with either hVEGF-A121 or hVEGF-A165 expression vector. The levels of VEGF-A121 and VEGF-A165 in serum, plasma, and platelets from 59 healthy volunteers proved that VEGF-A121 level was higher than VEGF-A165 in both plasma and serum in all the cases. VEGF-A121 or VEGF-A165 in serum represented higher level than that in plasma. In contrast, the level of VEGF-A165 was higher than VEGF-A121 in platelets. The newly developed ELISAs for hVEGF-A121 and hVEGF-A165 revealed different ratios of VEGF isoforms in serum, plasma, and platelets. Measuring these isoforms in combination provides useful information as biomarkers for diseases involving VEGF-A121 and VEGF-A165.

B cell-derived vascular endothelial growth factor A promotes lymphangiogenesis and high endothelial venule expansion in lymph nodes.

Vascular endothelial growth factor A (VEGF-A) is a prominent growth factor for both angiogenesis and lymphangiogenesis. Recent studies have shown the importance of VEGF-A in enhancing the growth of lymphatic endothelial cells in lymph nodes (LNs) and the migration of dendritic cells into LNs. VEGF-A is produced in inflamed tissues and/or in draining LNs, where B cells are a possible source of this growth factor. To study the effect of B cell-derived VEGF-A, we created transgenic mice (CD19(Cre)/hVEGF-A(fl)) that express human VEGF-A specifically in B cells. We found that the human VEGF-A produced by B cells not only induced lymphangiogenesis in LNs, but also induced the expansion of LNs and the development of high endothelial venules. Contrary to our expectation, we observed a significant decrease in the Ag-specific Ab production postimmunization with OVA and in the proinflammatory cytokine production postinoculation with LPS in these mice. Our findings suggest immunomodulatory effects of VEGF-A: B cell-derived VEGF-A promotes both lymphangiogenesis and angiogenesis within LNs, but then suppresses certain aspects of the ensuing immune responses.