C24 Sphingolipids Govern the Transbilayer Asymmetry of Cholesterol and Lateral Organization of Model and Live-Cell Plasma Membranes.

Mammalian sphingolipids, primarily with C24 or C16 acyl chains, reside in the outer leaflet of the plasma membrane. Curiously, little is known how C24 sphingolipids impact cholesterol and membrane microdomains. Here, we present evidence that C24 sphingomyelin, when placed in the outer leaflet, suppresses microdomains in giant unilamellar vesicles and also suppresses submicron domains in the plasma membrane of HeLa cells. Free energy calculations suggested that cholesterol has a preference for the inner leaflet if C24 sphingomyelin is in the outer leaflet. We indeed observe that cholesterol enriches in the inner leaflet (80%) if C24 sphingomyelin is in the outer leaflet. Similarly, cholesterol primarily resides in the cytoplasmic leaflet (80%) in the plasma membrane of human erythrocytes where C24 sphingolipids are naturally abundant in the outer leaflet. We conclude that C24 sphingomyelin uniquely interacts with cholesterol and regulates the lateral organization in asymmetric membranes, potentially by generating cholesterol asymmetry.

Pro-inflammatory and anti-inflammatory cytokine profiles in fetal growth restriction.

The purpose of this investigation was to measure cytokine production by maternal peripheral blood lymphocytes from women with intrauterine growth restriction (IUGR) and from healthy pregnant women, and to investigate the relationship between cytokine profiles and IUGR. Thirty-six women with IUGR and 22 control healthy pregnant women with normal fetal growth were studied. Levels of pro-inflammatory cytokines (IFNy, TNFa, IL-8, IL-12, IL-18, IL-23) and anti-inflammatory cytokines (IL-4, IL- 10, IL-13) produced by mitogen-stimulated peripheral blood mononuclear cells were measured by ELISA. Levels of the anti-inflammatory cytokine IL-4 were higher in normal pregnancy compared to IUGR, indicating an anti-inflammatory bias. Levels of the pro-inflammatory cytokines IL-6, TNFα, and IL-12 were significantly higher and levels of the anti-inflammatory cytokine IL- 10 lower in IUGR with placental insufficiency than in IUGR without placental insufficiency, suggesting a stronger pro-inflammatory bias in IUGR with placental insufficiency. Ratios of pro- to anti-inflammatory cytokines suggest a dominance of pro-inflammatory cytokines. The authors conclude that an increased pro-inflammatory cytokine bias is observed in IUGR compared to normal pregnancy, and an increased pro-inflammatory cytokine dominance is seen in IUGR with placental insufficiency compared to IUGR without placental insufficiency.

IL-10 and pregnancy complications.

PURPOSE OF INVESTIGATION: Successful pregnancy depends on the ability of the mother's immune system to undergo a process of immunoregulation in order to tolerate the fetus, and also to create and sustain a nurturing environment during all the stages of pregnancy. Several reports point to interleukin 10 (IL-10) as being vital for normal pregnancy, and low IL-10 levels as being associated with preg- nancy complications. This study aimed to compare IL-10 levels in normal and complicated pregnancy conditions. MATERIAL AND METHODS: The authors compared levels of IL-10 produced upon stimulation of maternal peripheral blood mononuclear cells (PBMC) from women at different stages of normal gestation with those produced by women with pregnancy complications, such as recurrent spontaneous miscarriage (RSM), preterm delivery (PTD), premature rupture of fetal membranes (PROM), pre-eclampsia, and intrauterine fetal growth retardation (IUGR). RESULTS: Median levels of IL-10 are statistically significantly lower in pathological conditions as com- pared to matching gestational ages of normal pregnancy. CONCLUSION: Healthy pregnancy is associated with higher levels of IL-10, while pathologic pregnancies are associated with lower levels of IL-10.

Cytokines as diagnostic markers of pulpal inflammation.

AIM: To measure and compare the levels of the cytokines IL-2, IL-6, IL-8, IL-10, TNF-α and IFN-γ in pulpal blood from irreversible pulpitis, asymptomatic caries exposure and normal pulps. METHODOLOGY: Blood was obtained from pulp exposure sites using cotton pellets. Twenty-five samples were obtained from normal teeth, 40 from asymptomatic caries-exposed pulps and 43 from irreversible pulpitis teeth. Cytokine levels were determined by high-sensitivity ELISA. Data were statistically analysed using Kruskal-Wallis and Mann-Whitney U-tests. RESULTS: Significantly higher levels (P < 0.05) of IL-6, IL-8, IL-10, TNF-α and IFN-γ were detected in caries-exposed pulps and irreversible pulpitis as compared to normal teeth. IL-2 and IL-10 levels were significantly higher (P < 0.05) in caries-exposed pulps as compared to irreversible pulpitis, whilst IL-8 was significantly higher (P < 0.001) in irreversible pulpitis as compared to caries-exposed teeth. Most interestingly, IL-6/IL-10 and IL-8/IL-10 ratios were significantly higher (P < 0.001) in irreversible pulpitis compared with both caries-exposed and normal teeth. CONCLUSION: Levels of IL-8 and the ratios of IL-6/IL-10 and IL-8/IL-10 have the potential to be indicators of pulpal inflammation in caries exposure cases. Cytokine estimation in pulpal blood may help in the diagnosis of pulpal inflammation.

Efficacy and safety of infliximab in active SLE: a pilot study.

Tumour necrosis factor-alpha (TNF-alpha) plays a major role in propagating the inflammatory processes responsible for tissue damage in systemic lupus erythematosus (SLE) and is overexpressed both systemically and locally in this disease. Hence, this pilot study was carried out to assess the safety and efficacy of TNF blockade in patients with active SLE. A total of 46 individuals (27 patients with active SLE and 19 healthy control volunteers) were the subjects of this study. Nine patients with SLE were allocated to treatment arm and 18 were allocated to control arm. In addition to conventional treatment, treatment arm received infliximab infusions 3 mg/kg body weight at 0, 2, 6 weeks and then q 8 weeks for a total of 24 weeks, that is, a total of five doses. Patients were closely monitored for infection. Clinical, laboratory and treatment data were entered into a pre-designed proforma. Health status (SF-36), patient global assessment (PGA) of disease activity, disease activity scores by SLEDAI and organ damage by SLICC/ACR-DI (American College Rheumatology) were measured at baseline and end of the study. Relevant immunological studies included serum levels of TNF-alpha and soluble TNF receptors-1 (p55 srTNF-alpha) and -2 (p75 srTNF-alpha), C3 and C4 complement levels, anti-dsDNA antibody titres (IgM, IgG and IgA isotypes), anti-cardiolipin titres (IgM, IgG and IgA isotypes) and anti-beta2GPI (Glycoprotein I) antibody titres (IgM, IgG and IgA isotypes). Four patients from treatment arm dropped out due to infliximab infusion reaction and 12 patients dropped out from the control arm. The treatment group showed significantly greater improvement in Systemic Lupus Erythematosus Disease Activity Index (SLEDAI). Improvements in several SF-36 subscales, PGA and VAS-Fatigue (Visual Analogue Scale) were also greater in the treatment group but did not achieve statistical significance. The mean levels of TNF-alpha, soluble TNF receptors-1 (p55 srTNF-alpha) and -2 (p75 srTNF-alpha) were higher in the SLE group compared with the healthy controls but did not change significantly over the study period. We did not face any safety issues with infliximab in this study. In view of improvement in several SLE parameters and good safety profile of infliximab, anti-TNF-alpha therapy is an interesting candidate approach for treating SLE.

Low levels of Th1-type cytokines and increased levels of Th2-type cytokines in kidney transplant recipients with active cytomegalovirus infection.

BACKGROUND: Cytomegalovirus (CMV) infection is a major complication after kidney transplantation. It is clear that Th1 and Th2 cell subsets are of major importance in determining the class of immunoprotective function in infectious diseases. Given the strong influence exerted by Th1- and Th2-type immunity on the outcome of infections, we felt it important to elucidate the levels of Th1- and Th2-type cytokines to CMV-related antigens in kidney recipients and to identify antigens that play an essential role in preventing the development of CMV infection and/or disease. METHODS: One hundred twenty subjects were followed for CMV infection by the antigenemia assay. We investigated peripheral blood mononuclear cells (PBMCs) responses to five CMV-related peptide antigens (pp65, gB, pp150, pp28, and pp38). Stimulation index was determined by radioactive thymidine uptake, while the production of Th1-type cytokines (interferon-gamma and tumor necrosis factor-alpha) and Th2-type cytokines (interleukins-4 and -10) were measured by enzyme-linked immunosorbent assay. RESULTS: The levels of Th1-type cytokine production after stimulating PBMCs with CMV-related antigens gB and pp150 resulted in significant decreases in the levels of interferon-gamma, while pp65, pp150, and pp38 produced significant decreases in the level of tumor necrosis factor-alpha between the two groups (P < .05). For Th2-type cytokines only pp28 produced a significant increase in the level of interleukin-10 between the two groups (P < .05). Regarding the Th1:Th2 ratios, a lower Th1-bias was observed among the CMV-positive patients for PBMCs stimulated with three CMV-related antigens (pp65, pp38, and pp28). CONCLUSION: Low levels of Th1-type cytokines and increased levels of Th2-type cytokines upon stimulation with CMV-related peptide antigens were associated with reduced cell-mediated immunity to CMV, thus seeming to correlate with active CMV infections.

Progesterone-induced blocking factor (PIBF) modulates cytokine production by lymphocytes from women with recurrent miscarriage or preterm delivery.

Spontaneous miscarriage and preterm delivery are common complications of pregnancy. Pro-inflammatory cytokines have been shown to be associated with recurrent spontaneous miscarriage (RSM) and preterm delivery (PTD) and these have led to exploration of ways to downregulate pro-inflammatory cytokines and/or to upregulate anti-inflammatory cytokines. Progesterone-induced blocking factor (PIBF) is a molecule with inhibitory effects on cell-mediated immune reactions. We have ascertained the effects of PIBF on secretion of selected type 1 and type 2 cytokines by peripheral blood mononuclear cells from healthy non-pregnant women, women undergoing normal pregnancy, women with unexplained RSM and women with PTD. Peripheral blood mononuclear cells from 30 women with a history of unexplained RSM, 18 women undergoing PTD, 11 women with normal pregnancy and 13 non-pregnant healthy women were stimulated with a mitogen in the absence and presence of PIBF after which the levels of cytokines released into culture supernatants were determined by ELISA. Production of the type 2 cytokines IL-4, IL-6 and IL-10 by lymphocytes from the RSM and PTD groups and of IL-4 and IL-10 by lymphocytes from healthy pregnant women was significantly increased upon exposure to PIBF, while the levels of type 1 cytokines were not affected. Ratios of type 1:type 2 cytokines were decreased, suggesting a shift towards Th2 bias. PIBF did not affect cytokine production by lymphocytes from non-pregnant women. Thus, PIBF acts on lymphocytes in pregnancy to induce a type 1 to type 2 cytokine shift by upregulating the production of type 2 cytokines.

Low levels of serum asymmetric antibodies as a marker of threatened pregnancy.

Tolerance to the developing fetus is thought to be accomplished through the action of several molecules that are able to modulate the maternal immune response. Among several mechanisms involved in pregnancy maintenance, progesterone-induced immunomodulation, asymmetric antibody (AAb) production, indoleamine 2,3-dioxygenase (IDO)-mediated tryptophan catabolism and Th1- to Th2-type cytokine balance have been particularly well studied. However, spontaneous abortions (SA) remain the most common complication of pregnancy, affecting 15% of women, primarily in the first trimester. Development of sensitive methods for the early diagnosis of this condition is therefore a matter of critical importance. In the present study, we investigated AAb production and IDO activity in pregnant women in order to assess their value as early markers for the diagnosis of pregnancy failure. Serum AAb percentages were significantly reduced in women who subsequently suffered from SA compared with controls (p<0.001). Levels of IL-10, IL-12 and IDO activity were also lower in the SA cases, although levels of significance were not reached. In view of these findings, low maternal serum AAb percentages during the first trimester of pregnancy may be indicative of a threat to pregnancy progression.

Is combined pretransplantation seropositivity of kidney transplant recipients for cytomegalovirus antigens (pp150 and pp28) a predictor for protection against infection?

OBJECTIVE: This study was aimed at detecting antibodies to the antigens which may contribute to protection against cytomegalovirus (CMV) infection after organ transplantation. MATERIALS AND METHODS: A total of 203 kidney transplant patients were enrolled in the study. Based on CMV antigenemia assay, 23 patients were antigen-positive and of the remaining 180 antigen-negative patients, 46 were selected as controls matched for age, gender and source of kidney. The 69 kidney recipients (KR) had CMV antibody due to previous infection and were followed up for a period of 6 months after transplantation for the development of active CMV infections by the antigenemia assay. Antibody responses to five CMV-related peptide antigens (pp65, gB, pp150, pp28 and pp38) were investigated by enzyme immunoassay and their presence was correlated with the results of the CMV antigenemia assay. RESULTS: Of the five CMV-related peptide antigens, only gB antigen showed response to the antibody in 10/23 (43.5%) antigen-positive patients and 9/46 antigen-negative patients and the difference was statistically significant (p = 0.048). On the other hand, there was no significant difference in antibody responses between the antigen-positive and antigen-negative KR to the other four CMV peptide antigens (p > 0.05). However, among the antigen-positive KR there was only 1 patient who had antibodies to both pp150 and pp28 antigen, while among the antigen-negative KR, 22 of 46 (47.8%) had the antibodies (p < 0.001). CONCLUSION: The findings suggest that the combined presence of antibodies against the pp150 and pp28 antigens may indicate a lower risk of CMV reactivation after kidney transplantation.

Modulation of the transforming growth factor beta1 by vitamin E in early nephropathy.

OBJECTIVE: The aim of this study was to investigate the pharmacological activity of an antioxidant, alpha-tocopherol (vitamin E, VE) in streptozotocin-induced diabetic rats and study its role in modulating the transforming growth factor beta1 (TGF-beta1). METHODS: Male Sprague-Dawley rats were treated with streptozotocin to induce diabetes. VE and/or insulin (INS) were administered daily during treatment periods of 3, 5, 7 and 10 days. Plasma glucose and fructosamine were measured in diabetic rats at the end of each treatment period. Samples of plasma, urine and renal cortex were analyzed for changes in protein and lysozyme excretion, reduced glutathione and malondialdehyde formation. TGF-beta1 was determined by ELISA and expression of TGF-beta1 mRNA was investigated by RT-PCR and Northern blot analysis. RESULTS: Diabetes-induced glycemic stress was suppressed by INS, VE or a combination of INS and VE. Diabetes-induced increases of glucose, protein and lysozyme excretion were markedly depressed after 10-day treatment with INS, VE and the combination of INS and VE. Decreased glutathione content in the renal cortex of diabetic rats recovered towards control values, especially after 10-day treatment. Malondialdehyde content increased in diabetic rats and was reduced towards control value following 7- and 10-day treatments. Treatment of diabetic rats with INS, VE or the combination of INS and VE decreased elevated TGF-beta1 in plasma, decreased excretion of TGF-beta1 in urine, and decreased renal cortex TGF-beta1 mRNA levels. CONCLUSIONS: Diabetes-induced overexpression of TGF-beta1 mRNA was suppressed by VE and INS after 5-, 7- and 10-day treatments. The results obtained with the antioxidant VE suggest that oxidative stress is involved in the development of diabetic nephropathy. Therefore, VE treatment may be effective in early stages of diabetic nephropathy to decrease or prevent pathological complications.

Pro-inflammatory maternal cytokine profile in preterm delivery.

PROBLEM: The objective of this study was to determine the levels of cytokines produced by maternal peripheral blood mononuclear cells (PBMC) upon stimulation with a mitogen, with autologous placental cells and with a trophoblast antigen extract. METHOD OF STUDY: Peripheral blood mononuclear cells from 54 women with a history of successful pregnancy and 30 women undergoing preterm delivery (PTD) were stimulated with the mitogen and antigens, and the cytokine levels in mitogen-stimulated culture supernatants assessed. RESULTS: Significantly higher levels of the type 1 cytokines, interferon (IFN)-gamma and interleukin (IL)-2, were produced by the PTD group than by the normal pregnancy group, which on the contrary showed significantly greater production of the type 2 cytokines, IL-4, IL-5 and IL-10. A comparison of the ratios of type 2 to type 1 cytokines is indicative of a type 1 cytokine bias in PTD. CONCLUSIONS: These data are suggestive of a maternal type 1 cytokine bias in PTD.

Quality of paper boards from arecanut leaf sheath.

A study was carried on utilizing arecanut leaf sheath for making paper boards. Paper boards were made with various combinations of arecanut leaf sheath with waste paper, 1:1, 1:2, 1:3, 3:1, 2:1, control (100% areca leaf sheath) and the qualities of these paper boards were tested as per the Bureau of Indian Standards (IS: 1060 (part-I)-1966). The paper boards made with more arecanut sheath materials had more resistance to water absorption. The addition of paper increased the substance weight of the paper boards. The 2:1 and 3:1 combinations of arecanut leaf sheath and waste paper had best tear strength, tensile strength, bursting strength and water resistance with minimum substance weight.

Th1 and Th2 cytokine profiles in recurrent aborters with successful pregnancy and with subsequent abortions.

BACKGROUND: This study compared Th1-Th2 cytokine profiles in a subgroup of recurrent aborters who had an abortion with those in a subgroup of recurrent aborters who had a successful pregnancy. METHODS: Fifty-four women with a history of at least three normal pregnancies, 24 women with a history of recurrent spontaneous abortion (RSA) followed by abortion (RSA-->A) and 39 women with a history of RSA followed by normal pregnancy (RSA-->N) were studied. Blood samples and placentas were obtained at the time of delivery or abortion; peripheral blood mononuclear cells were stimulated separately with phytohaemagglutinin and with autologous placental cells, and the secreted cytokines estimated. RESULTS: Peripheral blood mononuclear cells from the RSA-->N subgroup secreted higher concentrations of Th1-type cytokines as compared with normal pregnant women, indicating a higher Th1 bias in these women. However, women in the RSA-->N subgroup had significantly higher concentrations of Th2 cytokines as compared with women in the RSA-->A subgroup. A comparison of Th1:Th2 cytokine ratios indicated a higher Th2 bias in RSA-->N women as compared with RSA-->A women. CONCLUSIONS: We conclude that abortion-prone women who proceed to have successful pregnancy are more Th2-biased than abortion-prone women who abort, and that recurrent aborters who undergo spontaneous abortion have a stronger Th1 bias than aborters who have normal pregnancy.

Pregnancy: success and failure within the Th1/Th2/Th3 paradigm.

Evidence from studies on murine and human pregnancy points to a strong association between maternal Th2-type immunity and successful pregnancy on the one hand and between Th1-type immune reactivity and pregnancy loss on the other. While there is a paucity of data from human pregnancy indicating that Th1-type immune effectors actually lead to pregnancy, it is difficult to ignore the compelling evidence linking inappropriate Th1-type immunity to pregnancy loss. Th2-type immunity and TGF beta secreted by Th3 cells may play protective roles during pregnancy, hence the nexus between a Th2/Th3 shift and successful pregnancy. This paper examines these associations and discusses possible mechanisms underlying immunologically mediated pregnancy failure.

Cytokine patterns in maternal blood after premature rupture of membranes.

OBJECTIVE: To compare two types of cytokines, type 1, which activate cell-mediated reactions and are important in cytotoxic and delayed-type hypersensitivity reactions, and type 2, which encourage vigorous antibody production and are commonly found in association with humoral immune responses, in blood of women with premature rupture of membranes (PROM). METHODS: Forty-four women with histories of at least three successful pregnancies and who currently delivered normally served as controls. The PROM group consisted of 30 women with spontaneous rupture of fetal membranes at term. Peripheral blood mononuclear cells were stimulated separately with a mitogen, placental cells, and a trophoblast antigen extract, and the supernatants examined for type 1 and type 2 cytokines. RESULTS: Mitogen-stimulated blood cells produced significantly higher levels of type 1 cytokines in PROM women than in normal controls. Higher levels of the type 1 cytokine interferon-gamma were produced by PROM samples stimulated with autologous placental cells and with trophoblast antigens. Ratios of type 1 to type 2 cytokines were higher in PROM compared with normal pregnancy, and in some cases as much as 25-fold higher. CONCLUSION: Women in the PROM group had a stronger type 1 reactivity whereas normal women were more predisposed to type 2 immunity; thus, PROM appears to be associated with a maternal type 1 bias.

Th1 and Th2 cytokine profiles in sickle cell disease.

We have investigated the levels of Th1 (IL-2 and IFN-gamma) and Th2 (IL-4) cytokines in the plasma and supernatants following peripheral blood mononuclear cell culture and mitogen stimulation in a group of 39 patients with sickle cell disease (SCD) made up of 29 SS, 8 Sbeta-thal and 2 Hb SD in steady state. Five SS patients were studied during 7 episodes of vaso-occlusive crisis. Twenty-four control (3 Hb AS and 21 Hb AA) were also studied; 10 were acutely ill while 14 were healthy at the time of the study. The plasma levels of IL-2 and IFN-gamma were similar in the patients and the controls. However, plasma IL-4 was significantly higher among the steady-state SS patients than in the controls. While there was no significant difference in cytokine levels following mitogen stimulation in the different groups, plasma IL-2 to IL-4 and IFN-gamma to IL-4 ratios were significantly lower among the steady-state SS patients, indicating a possible Th2 bias in our sickle cell patients and suggesting a possible mechanism to explain the predisposition of SCD patients to bacterial infections. However, SS patients with good splenic function showed a relative Th1 bias, which may be an additional explanation for the protection against bacterial infections in such patients.

Circulating cytokines and CD30 in normal human pregnancy and recurrent spontaneous abortions.

Concentrations of the T-helper (Th) 1 cytokines interleukin (IL)-2, tumour necrosis factor (TNF) -alpha, TNF-beta and interferon-gamma, Th2 cytokines IL-4, IL-5, IL-6, IL-10 as well as those of soluble CD30 in sera have been examined during the three trimesters of gestation, at delivery in normal pregnancy, and at the time of spontaneous abortion in women with a history of unexplained recurrent spontaneous abortion (RSA). Significantly higher concentrations of the Th2 cytokines IL-6 and IL-10 were found at normal delivery than in women with RSA, and conversely significantly increased concentrations of the Th1-type cytokine TNF-alpha were found in RSA as compared with successful pregnancy. In abortion-prone women who had a successful pregnancy, significantly higher concentrations of IL-6 and significantly lower concentrations of TNF-alpha were found as compared with abortion-prone women who had another abortion, supporting the notion that Th2- and Th1-bias are associated with successful and unsuccessful pregnancy respectively. Serum CD30 concentrations did not correlate with the outcome of pregnancy. These findings support observations drawn from experiments on the cytokine secretion profiles of peripheral blood mononuclear cells and decidual lymphocytes which suggest that normal pregnancy is Th2-biased and that unexplained RSA is associated with Th1-type reactivity.