Pseudo-anaphylaxis to Polyethylene Glycol (PEG)-Coated Liposomes: Roles of Anti-PEG IgM and Complement Activation in a Porcine Model of Human Infusion Reactions

Polyethylene glycol (PEG)-coated nanopharmaceuticals can cause mild to severe hypersensitivity reactions (HSRs), which can occasionally be life threatening or even lethal. The phenomenon represents an unsolved immune barrier to the use of these drugs, yet its mechanism is poorly understood. This study showed that a single i.v. injection in pigs of a low dose of PEGylated liposomes (Doxebo) induced a massive rise of anti-PEG IgM in blood, peaking at days 7-9 and declining over 6 weeks. Bolus injections of PEG-liposomes during seroconversion resulted in anaphylactoid shock (pseudo-anaphylaxis) within 2-3 min, although similar treatments of naı̈ve animals led to only mild hemodynamic disturbance. Parallel measurement of pulmonary arterial pressure (PAP) and sC5b-9 in blood, taken as measures of HSR and complement activation, respectively, showed a concordant rise of the two variables within 3 min and a decline within 15 min, suggesting a causal relationship between complement activation and pulmonary hypertension. We also observed a rapid decline of anti-PEG IgM in the blood within minutes, increased binding of PEGylated liposomes to IgM⁺ B cells in the spleen of immunized animals compared to control, and increased C3 conversion by PEGylated liposomes in the serum of immunized pigs. These observations taken together suggest rapid binding of anti-PEG IgM to PEGylated liposomes, leading to complement activation via the classical pathway, entailing anaphylactoid shock and accelerated blood clearance of liposome-IgM complexes. These data suggest that complement activation plays a causal role in severe HSRs to PEGylated nanomedicines and that pigs can be used as a hazard identification model to assess the risk of HSRs in preclinical safety studies.

Activation of B-1 Cells Promotes Tumor Cell Killing in the Peritoneal Cavity

Metastatic cancer involving spread to the peritoneal cavity is referred to as peritoneal carcinomatosis and has a very poor prognosis. Activating the antitumor immune response in the characteristically immune-suppressive peritoneal environment presents a potential strategy to treat this disease. In this study, we show that a toll-like receptor (TLR) and C-type lectin receptor (CLR) agonist pairing of monophosphoryl lipid A (MPL) and trehalose-6,6'-dicorynomycolate (TDCM) effectively inhibits tumor growth and ascites development in a mouse model of aggressive mammary cancer-induced peritoneal carcinomatosis. MPL/TDCM treatment similarly inhibited peritoneal EL4 tumor growth and ascites development. These effects were not observed in mice lacking B cells or mice lacking CD19, which are deficient in B-1a cells, an innate-like B-cell population enriched in the peritoneal cavity. Remarkably, adoptive transfer of B-1a cells, but not splenic B cells from WT mice, restored MPL/TDCM-induced protection in mice with B-cell defects. Treatment induced B-1 cells to rapidly produce high levels of natural IgM reactive against tumor-associated carbohydrate antigens. Consistent with this, we found significant deposition of IgM and C3 on peritoneal tumor cells as early as 5 days post-treatment. Mice unable to secrete IgM or complement component C4 were not protected by MPL/TDCM treatment, indicating tumor killing was mediated by activation of the classical complement pathway. Collectively, our findings reveal an unsuspected role for B-1 cell-produced natural IgM in providing protection against tumor growth in the peritoneal cavity, thereby highlighting potential opportunities to develop novel therapeutic strategies for the prevention and treatment of peritoneal metastases. SIGNIFICANCE: This work identifies a critical antitumor role for innate-like B cells localized within the peritoneal cavity and demonstrates a novel strategy to activate their tumor-killing potential.See related commentary by Tripodo, p. 5.

Successful and Safe Long-Term Standard Antiviral Therapy in a Patient with "Explosive" Immune Response in Course of HCV-Related Liver Cirrhosis

Hepatitis C virus (HCV) has been recognized to be both a hepato- and lymphotropic virus. HCV lymphotropism represents an essential detail in the pathogenesis of virus-related autoimmune and lymphoproliferative disorders, ranging from clonal expansion of B-cells with organ and non-organ-specific autoantibody production up to overt non-Hodgkin’s lymphoma along a continuous step-by-step model of B-cell lymphomagenesis, where the intermediated mixed cryoglobulinemia could be considered as a stage of suppressible antigen-driven lymphoproliferation. The HCV long-lasting extrahepatic replicative state generates an abnormal systemic immunological response, including rheumatoid factor (RF) and cryo- and non-cryoprecipitable immune complexes, as well as clinical manifestations, comprising dermatitis, polyarthralgias and arthritis, pulmonary disease, aplastic anemia, glomerulonephritis and vasculitis. The mechanism of these extra-hepatic disorders is thought of as linked to immune complex disease, but their pathogenesis is poorly clarified. Immune-suppressive treatment could induce high-level hepatitis C viremia and impair hepatic disease. We report a female patient, whose chronic HCV-related liver cirrhosis with associated explosive, but oligosymptomatic lymphoproliferative immune response, i.e., RF beyond three thousand times the upper of normal range (unr), type II cryoglobulinemia with cryocrit 40% and monoclonal gammopathy IgM-k, has been successfully and safely treated by long-lasting (sixty-six months) combined antiviral therapy (pegylated interferon alfa and ribavirin), at moderate and tapering dose regimen, prolonged for nearly 24 months after the first viral suppression. At the last follow-up (fifty-one months), the patient was showing very-long term antiviral response, progressive decline of secondary immune activation and absence of significant side-effects. Further research is required to fully verify the real impact on therapeutic choice/regimen.

A time-course study of immune response in Japanese flounder Paralichthys olivaceus exposed to heavy oil

PURPOSE

The immunotoxicities of oil and its components on fish immunities have been investigated, but there is little literature on the recovery of the fish from the immune suppression. Therefore, the recovery of Japanese flounder Paralichthys olivaceus from an immunosuppressive effect due to heavy oil (HO) exposure was investigated in this study.

METHODS

Fish were exposed to HO at a concentration of 0.385 g/L for 2 days, while control fish received no exposure. Seven fish were sampled at 0, 3, 7, and 14 days post-exposure. The respiratory rate was measured everyday as an indicator of the acute effect of HO exposure. Fish serum was collected and used for antibacterial activity assay against Edwardsiella tarda. Expression changes of respiratory and immune-related genes were evaluated by real-time PCR.

RESULTS AND DISCUSSION

The respiratory rate was significantly increased in the HO-exposed group until 4 days post-exposure. A respiratory-related gene, β-hemoglobin, was also significantly downregulated in the spleen both at 0 and 7 days post-exposure and kidney at 3 days post-exposure in HO-exposed fish. Immunotoxicity, including suppression of antibacterial activities and downregulation of the IgM gene, was observed in HO-exposed fish until 3 days post-exposure, but not after that time. From these results, we conclude that the fish likely return to normal status around 1 week.

Pregnancy outcome in women with antiphospholipid syndrome on low-dose aspirin and heparin: a retrospective study

This retrospective review of hospital records analysed pregnancy outcome with 2 different treatments for women with recurrent miscarriage diagnosed with antiphospholipid syndrome in the index pregnancy. Of 64 women, 29 had received aspirin and 35 aspirin plus heparin. Pregnancy-induced hypertension, prematurity, intrauterine growth restriction and neonatal death were considered as maternal and fetal complications. There were no significant differences in antenatal and maternal complications between the groups. HOwever, there were significant differences in mean anticardiolipin IgG antibody levels. Aspirin alone or in combination with parin was equally efficacious in women with antiphospholipid syndrome and recurrent miscarriage.

Effect of zinc supplementation on mycospecific immunoglobulins in tuberculosis patients

The effect of zinc supplementation on the serum level of IgA, IgG, IgM mycospecific immunoglobulins in tuberculosis patients alongwith normal control and disease control subjects were studied. It was observed that with antituberculous drugs for one month (without zinc supplementation), the serum level of immunoglobulins in tuberculosis subjects although decreased significantly, but with zinc supplementation along with antituberculous drugs for one month the decrease in the level of immunoglobulins in serum was more significant. This may be attributed to the effect of zinc supplementation favouring the normal compartmentalisation state of iron and also to the immunomodulatory effect of zinc.

Bortezomib affects the function of human B cells: possible implications for desensitization protocols

Bortezomib is a potent inducer of apoptosis in malignant as well as non-malignant human plasma cells. Recently, bortezomib has come to attention for the treatment of humoral rejection. As bortezomib is a proteasome inhibitor, it likely affects other cell types, such as activated B cells, as well. Since additional anti-B cell effects could be beneficial for the treatment of humoral rejection, we tested whether bortezomib inhibited human B cell function. When B cells were activated in a CD40 mAb driven culture system, bortezomib dose-dependently abrogated their IgM and IgG production as well as their proliferation. This bortezomib induced inhibition was caused by induction of apoptosis, since levels of caspase 3/7 activity were increased. In addition to its effects on plasma cells, bortezomib profoundly inhibits activated human B cells. This finding suggests that when bortezomib is used for desensitization or for the treatment of humoral rejection, there is no need for additional anti-B cell therapy, such as anti-CD20 mAb (Rituximab) treatment.

Atlantic salmon (Salmo salar L.) parr fed genetically modified soybeans and maize: Histological, digestive, metabolic, and immunological investigations

Physiological and health related responses to dietary inclusion of genetically modified (GM) full-fat soybean meal (Roundup Ready; GM-soy) and maize (MON810 Bt-maize; GM-maize), as well as non-parental, untransformed lines (nGM-soy and nGM-maize D2), were evaluated in farmed Atlantic salmon (Salmo salar L.) parr during the first 8 months of feeding. Significant effects of dietary GM presence were only found in intestinal Na+-dependent d-glucose uptake and SGLT1 protein level in the region pyloric caeca in which the highest values were found in the GM-soy, intermediate in the nGM-soy, and lowest in the standard FM fed groups. Data from this study confirm that GM soybeans (RRS) and maize (MON810) at inclusion levels of about 6% appear to be as safe as commercially available nGM soy and maize in diets for Atlantic salmon parr. Results from studies with higher inclusion levels and with non-modified, isogenic or near-isogenic parental lines as control groups are pending.

[Immunological aspects of aphthous stomatitis]

The purpose of the present work was to study the role of cellular and humoral immunity in patients with aphthous stomatitis. The research was conducted at Tbilisi Hospital for War Veterans. Immunologic parameters of 61 patients aged from 15 to 60 years old were analyzed. The statistical data processing included calculation of average arithmetic values and their standard deviations. Parameters of the immune status of the patients during exacerbation and under treatment were investigated. It was revealed that during exacerbation of stomatitis the quantity of CD3, CD4, cytophagous activity, and NK were diminished. Indices of CD8, CD72, and IgA, were within the norm. Indices of IgM, IgG, IgE, parameter of IL-6, antimicrobial and antitoxic antibody titer were increased. After treatment increase and approach to standard CD3, CD4, NK, and parameters of phagocytosis. IgG, IgM and antitoxic antibody titer decrease and approach to standard. During exacerbation of recurrent aphthous stomatitis the immune status of the human decrease, this is restored after treatment.

Predictors of response to rituximab in patients with neuropathy and anti-myelin associated glycoprotein immunoglobulin M

We evaluated the efficacy and safety of rituximab in an open-label, uncontrolled study of 13 patients with polyneuropathy associated with antibodies to myelin-associated glycoprotein (MAG) and correlated the response to therapy with clinical and laboratory features. One year after rituximab therapy, anti-MAG immunoglobulin M (IgM) titers were significantly reduced. At that time, eight patients (62%) had improved in both the inflammatory neuropathy cause and treatment (INCAT) sensory sumscore and the Medical Research Council sumscore for muscle strength and seven of them also in the INCAT disability score. The improvement in the mean INCAT sensory sumscore was significant at 12 months and correlated with lower anti-MAG antibody at entry and at follow-up. This study suggests that rituximab may be efficacious in patients with anti-MAG associated neuropathy and particularly on sensory impairment and in those with moderately elevated antibody titers. These findings suggest that antibody reduction below a critical level may be necessary to achieve clinical improvement.

Oxidation of low-density lipoprotein cholesterol following administration of poloxamer 407 to mice results from an indirect effect

Atherosclerosis is an inflammatory response to accumulation of cholesterol in the artery wall. Low-density lipoproteins (LDL) accumulate and are oxidized to proinflammatory compounds in the arterial intima during hypercholesterolemia, leading to activation of endothelial cells, macrophages, and T cells. We sought to define the role of oxidized LDL (oxLDL) in the poloxamer 407 (P-407)-induced mouse model of dose-dependent hyperlipidemia and atherosclerosis developed in our laboratory. The hyperlipidemic agent P-407 was evaluated for its ability to oxidize native LDL in vitro as determined by measuring the rate of formation of conjugated dienes, as well as malondialdehyde (MDA) production using the thiobarbituric acid reactive substances assay. Additionally, plasma obtained from C57BL/6 mice treated with P-407 for 100 days and maintained on either a normal diet or a diet supplemented with 0.5% w/w cholic acid was assayed for both MDA and lipid hydroperoxide content. Lastly, plasma from these same groups of mice was analyzed for the presence of immunoglobulin (Ig) G and IgM autoantibodies against oxLDL. Our results indicate that P-407 is unable to directly oxidize native LDL in vitro. However, plasma obtained from P-407-treated mice demonstrated a significant (P < 0.05) increase in the content of oxidized lipids, but showed a significant (P < 0.05) decrease in the concentration of lipid hydroperoxides when compared to controls. Both plasma IgG and IgM antibodies to MDA-modified LDL (MDA-LDL) were significantly (P < 0.05) elevated in P-407-treated mice, as was IgG1 anti-MDA-LDL, whereas the titer of IgG2a anti-MDA-LDL was significantly (P < 0.05) reduced. We suggest that P-407 causes oxidation of LDL in vivo by an indirect mechanism and we further conclude that P-407-induced hypercholesterolemia in C57BL/6 mice is associated with T cell-dependent (IgG) and T cell-independent (IgM) B-cell responses to MDA-LDL.

Role for Btg1 and Btg2 in growth arrest of WEHI-231 cells through arginine methylation following membrane immunoglobulin engagement

Engagement of membrane Ig (mIg) on WEHI-231 murine B lymphoma cells, a cell line model representative of primary immature B cells, results in growth arrest and subsequent apoptosis. Of the several dozen genes upregulated greater than two-fold by anti-IgM treatment through DNA microarray analysis, we focused on B cell translocation gene 1 (Btg1) and Btg2, member of Btg/Tob family of proteins. WEHI-231 cells were infected with the Btg1/EGFP or Btg2/EGFP retroviral vectors, and those expressing either Btg1 or Btg2 accumulated in G1 phase at significantly higher proportions than that seen for cells expressing control vector. Btg1 or Btg2 bound to protein arginine methyltransferase (PRMT) 1 via the box C region, an interaction required for anti-IgM-induced growth inhibition. The arginine methyltransferase inhibitor AdOx partially abrogated growth inhibition induced by Btg1, Btg2, or anti-IgM. The Btg1- or Btg2-induced growth inhibition was also abrogated in PRMT1-deficient cells via introduction of small interference RNA. In addition, we observed anti-IgM-induced arginine methylation of two proteins, a 28-kDa and a 36-kDa protein. Methylation, detected by a monoclonal antibody specific for asymmetric, but not symmetric methyl residues, was observed as early as 1 h-2 h after stimulation and was sustained for up to 24 h. The anti-IgM-induced p36 arginine methylation was abrogated in the PRMT1-deficient cells, suggesting that PRMT1 induces p36 methylation. Together, these results suggest that anti-IgM-induced growth inhibition is mediated via upregulation of Btg1 and Btg2, resulting in the activation of arginine methyltransferase activity and culminating in growth inhibition of WEHI-231 cells.

HCV-NS3 and IgG-Fc crossreactive IgM in patients with type II mixed cryoglobulinemia and B-cell clonal proliferations

We demonstrate that in three cases of MC (two with immunocytoma), the IgM-RF+ component of their cryoprecipitated represents the circulating counterpart of the B-cell receptor (BCR) of the monoclonal overexpanded B-cell population. These IgMs were isolated and used to demonstrate a crossreactivity against both hepatitis C virus (HCV) NS3 antigen and the Fc portion of IgG. Epitopes were identified in a fraction of exemplary samples by using epitope excision approach (NS(31250-1334) and IgG Fc(345-355)). The same phenomenon of crossreactivity has been shown to occur in vivo after immunization of a mouse with the NS3(1251-1270) peptide. To verify if the same reaction was also present in MC samples characterized by an oligo/polyclonal B-cell proliferation, IgM crossreactivity was tested in 14 additional samples. Five out of the 14 were reactive against HCV NS3 and 11 out of 14 were reactive against IgG-Fc peptide. The data support the role of HCV NS3 antigen in a subset of patients with MC, whereas the high frequency of the IgG-Fc epitope suggests that these B cells originate from precursors strongly selected for auto-IgG specificity. We suggest that engagement of specific BCRs by NS3 (or NS3-immunocomplex) antigen could explain the prevalence of IgM cryoglobulins in these patients.

The effect of oral immuno-stimulation in juvenile carp (Cyprinus carpio L.)

The effect of a 2-week period of oral immuno-stimulation from the age of 2 or 6 weeks post-fertilisation (wpf; before and after reaching the ability to produce antibodies) onwards was investigated on various immune functions of the common carp, Cyprinus carpio. The immuno-stimulants Aeromonas salmonicida lipopolysaccharide, Yeast DNA (containing unmethylated CpG motifs) or high-M alginate (an extract of algae containing poly-mannuronic acid) were used. The effect of this treatment was studied on the kinetics of B cells in head kidney and peripheral blood leucocytes using flow cytometry, on the total plasma IgM level using ELISA, on cytokine and inducible nitric oxide synthase (iNOS) expression in the intestine, and acute phase protein expression in the liver, using real time quantitative PCR, and on exposure to Vibrio anguillarum. Oral administration of immuno-stimulants from 6 wpf resulted in decreased WCI12(+) (B) cell percentages in PBL (only after administration of LPS) and head kidney (all test groups), and a decreased total IgM level in plasma, suggesting that suppressive effects are strongly indicative of oral or juvenile tolerance. After administration from 2 wpf, the effects on WCI12(+) (B) cell percentages were less pronounced: the group fed with Yeast DNA showed higher percentages compared to the control group at 6 wpf, but lower percentages at 8 wpf. No changes were observed in the cytokine or iNOS expression levels in the intestine or acute phase protein expression in the liver. A challenge with V. anguillarum resulted in an initially higher cumulative mortality in the group fed with LPS, but lower mortality in the groups fed with Yeast DNA or high-M alginate compared to the control group, providing a provisional warning especially for the use of pathogen-derived immuno-stimulants, such as A. salmonicida LPS, in larval and juvenile fish.

Effects of morphine and its metabolites on immune function in advanced cancer patients

STUDY OBJECTIVE

To determine whether morphine and its active metabolites such as morphine-3-glucuronide (M-3-G) and morphine-6-glucuronide (M-6-G) modulate immune function in patients with advanced cancer who required morphine for pain relief.

DESIGN

Prospective observational clinical study.

SETTING

Pain clinic of a university hospital.

PATIENTS

Fifteen patients who visited our clinic for control of advanced cancer pain.

INTERVENTIONS

During the initiation or changes of morphine therapy, venous blood samples were obtained at the enrollment of this study, 1 and 3 weeks after the change of morphine dose or route.

MEASUREMENTS

Lymphocyte subpopulation CD4+ and CD8+, activity of natural killer cell, phytohemagglutinin (PHA)-induced T-cell proliferation, and plasma immunoglobulin M and G concentrations were measured, as well as plasma concentrations of morphine, M-3-G, and M-6-G.

MAIN RESULTS

At the entry of the study, 6 patients did not receive any type of morphine medication (group 1), whereas 9 patients were treated with morphine for 1 month (group 2). Cancer pain, rated as 4 at the entry period, was reduced to 2 of 10 (visual analogue scale) during the study periods. Although the plasma concentrations of M-3-G and M-6-G in Group 1 were significantly less than those in Group 2, plasma concentrations of immunologic markers were similar between the groups. In Group 1, Spearman linear regression analysis showed negative correlation between morphine-derived metabolites and immunoglobulins or PHA-induced T-cell proliferation, whereas poor correlation was found with all immunologic parameters in Group 2. Stepwise linear regression analyses showed that the metabolites, rather than morphine per se, modulated immune function, reflected by PHA-induced T-cell proliferation and immunoglobulin G concentration in Group 1.

CONCLUSIONS

The present study suggests that some of humoral and cellular immunity are modulated by morphine-derived metabolites at the early phase of morphine therapy in patients with advanced cancer.

Single agent rituximab in patients with follicular or mantle cell lymphoma: clinical and biological factors that are predictive of response and event-free survival as well as the effect of rituximab on the immune system: a study of the Swiss Group for Clinical Cancer Research (SAKK)

BACKGROUND

Predictive factors of rituximab efficacy and its effect on the immune system are still not defined.

PATIENTS AND METHODS

Three hundred and six patients with follicular or mantle cell lymphoma received four weekly doses of rituximab (induction) and no further treatment (arm A) or four more doses at 2-month intervals (arm B).

RESULTS

Response rate to induction was 44%. Independent predictive factors for response were disease bulk <5 cm, follicular histology, normal hemoglobin and low lymphocyte count. Factors associated with event-free survival (EFS) were having responded to induction, having received not more than one line of therapy, Ann Arbor stage I-III, high lymphocyte count, disease bulk <5 cm, Fc-gamma receptor genotype VV and receiving prolonged treatment. B cells were suppressed by treatment but recovered after a median of 12 months in arm A and 18 months in arm B. The median IgM level after 1 year was normal in arm A but was decreased to 73% of baseline in arm B. We observed 24 serious adverse events, equally distributed between arms. Ten patients receiving induction only and six patients receiving prolonged treatment developed a second tumor.

CONCLUSIONS

We defined the characteristics predicting response and EFS to rituximab. Prolonged treatment results in longer EFS at the cost of a longer reduction in B cell and IgM levels, but without additional clinical toxicity.

[Efficacy of galavit in patients with duodenal ulcer]

The aim of the study was to investigate clinical efficacy of the medical complex Galavit in patients with acute phase of duodenal ulcer (DU) in. The subjects were 60 DU patients aged 32 +/- 2 years with ulcerous defects of 0.4 to 1.3 cm in diameter. In patients receiving Galavit, pain was coped with by Mann-Whitney method in 2.5 +/- 0.2 days, p < 0.001; in the control group--in 5.7 +/- 0.1 days. In the Galavit group the ulcers healed in 11.3 +/- 0.2 days, p < 0.001; in the control group--17.8 +/- 0.3 days; in 4 cases (13.3%) the ulcerous defects healed with forming of rough scars. Galavit elevated T-lymphocyte rate from 53.1 +/- 0.6% to 65.1 +/- 0.2%, p < 0.001; T-helper inductor level--from 27.8 +/- 0.2% to 38.5 +/- 0.3%, p < 0.001; cytotoxic T-lymphocyte level--from 18.5 +/- 0.5% to 27.3 +/- 0.3%, p < 0.001; B-lymphocyte level--from 12.3 +/- 0.2% to 19.1 +/- 0.1%, p < 0.001. The therapy significantly lowered malonic aldehyde level by 23.5%, trienoic conjugate level--by 61.6%; superoxide dismutase level rose 1.6 times, catalase level--1.4 times, glutathion reductase level--from 19.03 +/- 1.17 to 27.01 +/- 1.24 optical density units/mg, p < 0.001. The study did not find any significant changes in the immune status and lipid peroxidative/antioxidative system of patients receiving basic therapy. The results show that Galavit has anti-inflammatory effect, improves immune status and anti-oxidative protection. It is appropriate to administer Galavit as a component of DU basic therapy. The results show that Galavit has anti-inflammatory effect, improves immune status and anti-oxidative protection. It is appropriate to administer Galavit as a component of DU basic therapy.

[Isotype switch in the response against T independent antigens by co-inoculation with T dependent antigens]

A classical paradigm in immunology establishes that for the isotype switch to take place in antibodies, it is a sine qua non condition that the antigen is presented by an antigen presenting cell to a helper T cell. In the present study an animal model of the immune response against two typical antigens was designed in BALB/c mice. Dextran was chosen as a T independent antigen (TIAg), and bovine seroalbumin (BSA) as a T dependant antigen (TDAg), and the response was studied, analyzing the isotypes of the specific antibodies produced. The results show that the response against dextran, in the presence of BSA, takes place with isotype switch, essentially from IgM to IgG1. These experiments suggest that BSA generates a switch inductor biochemical environment in its own processing pathway as well as in the dextran's. These results indicate that the exclusive association of TDAgs with isotype switch responses is inaccurate. Considering the proposed model, it seems unlikely the finding of a spontaneous in vivo case in which TIAgs enter the organism isolated; instead, it is much more probable that they would enter together with TDAgs, and in consequence the isotype switch would take place.

The implementation of factor analysis for the evaluation of selected blood parameter changes induced by hyperbaric exposure

This paper discusses the application of factor analysis when used to compare selected blood parameter (a three-parameter smear, hematocrit, C3c, C4, IgG, IgA, IgM, CRP, fibrinogen and the level of factor XII) properties, just before, and after exposure to pressure changes, and 24-hours after the completion of decompression. To-date the most popular method of statistical analysis was based only on investigation of the significance of the separated individual parameters. This factor analysis that has not been applied previously in the analysis of such problems, enabled the neutral hierarchic evaluation of the significant parameter changes within their chosen range, and mutual relationships. It seems that the application of this method is purposeful and it can be an objective tool for evaluating the significance of changes in blood constituency induced by pressure.

Trial of lamivudine in hepatitis B surface antigen carriers with persistent hepatitis B core IgM antibody

OBJECTIVE

The persistence of hepatitis B core immunoglobulin M (HBc IgM) antibody in hepatitis B surface antigen (HBsAg) carriers is a risk factor with hidden dangers and forecasts the existence of liver damage. A trial of lamivudine in such subset of carriers was carried out for the first time in this study.

METHODS

A total of 62 HBsAg with hepatitis e antibody individuals (age range, 25-45 years) with persistent HBc IgM antibody were randomized to receive either 100 mg lamivudine (32/62) or placebo (30/62) daily for 6 months. The study was performed from June 2000 to October 2002. The carriers were regular attendees of the Virology Center in Mosul, North Iraq for follow up. Enzyme-linked immunosorbent assay technique was performed to detect the different hepatitis B virus markers.

RESULTS

Among the lamivudine group, HBc IgM antibody seroclearance achievement rate was 81.3% and HBsAg seroconversion rate was 9.4% compared to 6.3% and 3.3% in the placebo group. Number of adverse clinical events were observed, but were of mild nature and tolerable by the participants who completed the study.

CONCLUSION

The trial of lamivudine in this subset of HBsAg carriers proved to be safe and efficacious. More studies are needed prior to recommending the drug for routine use on selected HBV carriers.

Clustering of the B Cell Receptor Is Not Required for the Apoptotic Response

We examined the role of BCR cell membrane redistribution in anti-IgM-induced apoptosis in three human B cell lines, RA#1, 2G6, and MC116, that differ in their relative levels of sIgM expression. The apoptotic response was found to be dependent on the nature of the anti-IgM and the cell line. In the cell lines, RA#1 and MC116, sIgM aggregated into patches that were insensitive to the disruption of cholesterol-rich membrane microdomains by nystatin or beta-MCD. The B cell line 2G6 was able to reorganize sIgM into a tight coalescent cap upon anti-IgM treatment. However, in this case, the lipid raft inhibitors nystatin and beta-MCD disrupted the patching. In 2G6 cells, BCR-mediated apoptosis was not affected by nystatin treatment, whereas it increased in beta-MCD pretreated cells. Thus, no evident correlation was found between apoptosis and BCR cell membrane redistribution or lipid raft formation in either of the three cell lines. The data indicate that the apoptotic signal transduction pathway is independent of BCR translocation into lipid rafts and/or aggregation.

Quinine-induced disseminated intravascular coagulation: case report and review of the literature

OBJECTIVE

To describe the clinical course of quinine-induced disseminated intravascular coagulation (DIC) and review all previous cases reported in the medical literature.

DESIGN

Case report/literature review.

SETTING

University teaching hospital medical ICU.

PATIENTS

One patient in whom thrombocytopenia, coagulopathy, intravascular hemolysis, DIC, and acute renal failure temporally followed the ingestion of quinine.

DATA SOURCES

We conducted a computerized free-text MEDLINE database search from 1969 to 2000 using the keywords quinine and thrombocytopenia, quinine and hemolytic-uremic syndrome, and quinine and disseminated intravascular coagulation.

STUDY SELECTION

All reported cases and reviews of quinine-induced thrombocytopenia, hemolytic-uremic syndrome (HUS), and DIC were reviewed. DIC was distinguished from quinine-induced thrombocytopenia or quinine-induced HUS based on the presence of abnormal clotting times, elevated fibrin degradation products, and/or elevated D-dimer levels.

DATA SYNTHESIS

Fifteen previous patients were found to meet the criteria for DIC temporally related to the recent ingestion of quinine. The clinical course and laboratory abnormalities documented for each case are reviewed.

CONCLUSIONS

Quinine-induced DIC is a distinct clinical entity, which may present as unexplained thrombocytopenia, coagulopathy, or renal failure. In susceptible patients, the immune response to quinine may result in the production of not only anti-platelet antibodies but also antibodies against leukocytes, erythrocytes, and endothelial cells. Furthermore, the varying patterns and specificities of antibody production in an individual patient may result in a spectrum of clinical disease from mild, transient thrombocytopenia to overt intravascular hemolysis, renal failure, coagulopathy, and DIC. Early recognition of quinine-induced DIC is paramount, as this diagnosis affords a better prognosis than other adult forms of HUS or DIC.

Changes of selected morphotic parameters and blood plasma proteins in blood of divers after a single short-time operational heliox exposure

In the Polish Navy, deep-water dives, performed for the needs of the maritime industry, are conducted using our own national technology and trimix as a breathing medium. In this paper are presented the results obtained during a short-time deep-water diving test using the principles of US Navy technology, combined with the use of diving equipment type AF-2 and heliox-type breathing mixture in the open circuit. In the performed examinations changes in clinical parameters were assessed viz.: blood morphology, hematocrit level, concentration of C3c, C4, IgG, IgA, IgM, CRP, concentration of fibrinogen and factor XII level, obtained 30 minutes prior to commencement, immediately after completion, and 24 hours after termination of the exposure. The results thus generated were subjected to a preliminary analysis by the description of trends observed. It was revealed that the diving technology employed did not generate substantial changes in the examined parameters of blood in divers, and the increase of neutrophils, blood platelets and fibrinogen concentration in the blood plasma immediately after diving is of temporary character, being a typical reaction observed during diving.

IL-4 supplemented B-cell cultures of allergic children show reduced IgA and IgG production in response to additional stimulation with IL-10

BACKGROUND

Cytokines play an important role in mediating immunoglobulin switch, the secretion of protective mucosal immunoglobulins, and the development of allergic diseases. This study investigates whether B cells from allergic and healthy children have different capacities to secrete immunoglobulins after stimulation with IL-4, IL-6, IL-10, IL-11, and IL13.

METHODS

We analyzed the peripheral venous blood of 44 healthy probands and of 109 allergic patients with a mean age of 13 years, allergic to grass pollen, birch pollen, and house dust mites. Lymphocytes were isolated by a density gradient and B cells were enriched by using a Magnetic Activated Cell Separator (MACS) and anti-CD19 microbeads. B Cells were co-cultured with human CDw32 (Fc gammaRII) expressing mouse Ltk fibroblasts and mouse anti-human CD40 monoclonal antibodies (CD40 system). The interleukins IL-4, IL-6, IL-10, IL-11, and IL-13 were supplemented in various combinations. After 14 days, concentrations of IgE, IgG, IgA, and IgM were measured in the supernatants with ELISA.

RESULTS

Suppression of IgA-, IgG, and IgM- synthesis was induced by stimulation of B cells with IL-4. After additional application of IL-10, IgA, IgG, and IgM synthesis was significantly increased. When cultures stimulated with IL-4 were additionally supplemented with IL-10, IgA, and IgG synthesis of B cells obtained from allergic individuals was significantly decreased compared to nonallergic individuals. IgE-secretion of B cells from allergic individuals was significantly increased compared to nonallergic individuals after stimulation with IL-4.

CONCLUSION

Our results implicate that IL-4 is essential for the regulation of immunoglobulin class switch to IgE and that IL-4 is an important cytokine for the development of allergic diseases. The capacity of B cells in allergic children to produce less IgA and IgG in response to additional stimulation with IL-10 of cultures supplemented with IL-4 could play an important role in mediating a mucosal immune system vulnerable to allergens. This phenomenon could contribute to the pathogenesis of allergic diseases.

Wheat gliadin promotes the interleukin-4-induced IgE production by normal human peripheral mononuclear cells through a redox-dependent mechanism

Increased levels of serum IgE have been described in gliadin-intolerant patients; however, biological mechanisms implicated in this immunoglobulin production remained unknown. In this study, we demonstrated that in vitro crude gliadins and gliadin lysates (Glilys) promoted the IL-4-induced IgE production by human peripheral blood mononuclear cells (PBMC), indicating that the biological process related to gliadin intolerance and/or allergy may lead to IgE production in vivo. It was found that crude gliadin and Glilys potentiated, after 13 days of culture in a dose-dependent manner, IL-4-induced IgE production and, to a lesser extent, the IgG production, while they did not affect IgA or IgM productions. This promoting effect of gliadin and Glilys on the IL-4-induced activation of normal human PBMC was also observed on the early release (2 days) of the soluble fraction of CD23, suggesting its possible involvement in IgE potentiation. The promoting effect of crude gliadin and Glilys appeared to be indirect because they did not modify purified B-lymphocytes IgE production after IL-4 and anti-CD40 monoclonal antibody stimulation. In addition, as revealed by luminol-dependent chemiluminescence, we demonstrated that crude gliadin and Glilys promoted a substantial production of free radicals by normal human PBMC, treated or not with IL-4. This redox imbalance associated with an increased IgE production led us to evaluate the effect of pharmacological antioxidants (N-acetyl-cysteine (NAC) and Cu/Zn-superoxide dismutase (SOD1)) on IgE production by human PBMC. The NAC and the intracellularly delivered SOD1 were found to suppress the IL-4+/-crude gliadin or Glilys-induced IgE production by normal human PBMC. Taken together, these data indicated that gliadin specifically enhanced IL-4-induced IgE production by normal human PBMC, probably by the regulation of redox pathways, and that this 'pro-allergenic' effect could be counteracted by natural antioxidants: thiols and/or vectorized SOD1.

Vaccination stimulates retinal ganglion cell regeneration in the adult optic nerve

We examined whether vaccination of adult rats with spinal cord homogenate (SCH) can promote regeneration of retinal ganglion cells (RGCs) after microcrush lesion of the optic nerve. Injured animals vaccinated with SCH showed axon growth into the optic nerve and such regeneration was not observed in animals vaccinated with liver homogenate (LH). Regeneration was not a consequence of neuroprotection since our vaccine did not protect RGCs from axotomy-induced cell death. Sera of vaccinated animals were tested for antibodies against myelin-associated glycoprotein, NogoA, Nogo-66 receptor, or chondroitin sulphate proteoglycans (CSPG), but no significant levels were detected. Antibodies to myelin basic protein were present in the serum of some SCH-vaccinated animals. In culture, serum from SCH-vaccinated animals promoted RGC growth on myelin but not on CSPG. Our results show that the effect of the pro-regenerative vaccine is mediated by antibodies to SCH. However, we were not able to detect a significant immune reaction to growth inhibitory proteins, suggesting alternative mechanisms for the success of vaccination to promote regeneration.

A novel phenoxazine derivative suppresses surface IgM expression in DT40 B cell line

1. 2-amino-4, 4alpha-dihydro-4alpha, 7-dimethyl-3H-phenoxazine-3-one (Phx) has been demonstrated to be an actinomycin D-like phenoxazine, and to display anti-tumour activity. 2. In this study, we report on the effect of Phx on B cell antigen receptor (BCR) and receptor-mediated signalling in DT40 B cells. 3. Treatment of B cells with Phx for 12 h inhibited BCR-stimulated tyrosine phosphorylation of cellular proteins. 4. B cells exposed to Phx exhibited down-regulation of surface IgM which is part of BCR. In contracts with actinomycin D, Phx rapidly reduced the expression of IgM without decreasing the expression of other signalling molecules. 5. Analysis with confocal microscopy demonstrated that Phx treatment reduced IgM expression both at the cell surface and inside the cell. 6. Treatment of B cells with Phx resulted in the reduction of IgM secretion. Since MG-132, a proteasomal inhibitor, restored IgM contents to the control levels, Phx has the specific effect of accelerating IgM degradation. 7. These results suggest that Phx down-regulates the expression of IgM and inhibits BCR-mediated signalling and IgM secretion. Phx may be useful as an immunosuppressive agent for therapeutic purposes.

Sex differences in photoperiod control of antigen-specific primary and secondary humoral immunity in Siberian Hamsters

Photoperiod was hypothesized to mediate T cell-dependent B cell production of IgM and IgG. Antigens induced production of specific immunoglobulins; serum IgM but not IgG, was higher in males in long vs. short days (16 vs. 8 h light/day) and similarly among all groups of females. A second immunization with KLH robustly enhanced serum IgM, as well as IgG; increases were blunted in short- vs. long-day males but not in females. Thus, in male but not female hamsters, winter-like short days restrain aspects of primary and secondary humoral immune responses to xenoantigens. Actions on lymphocyte activities or clonal expansion are in considerations.

Induction of p53-specific immune responses in colorectal cancer patients receiving a recombinant ALVAC-p53 candidate vaccine

PURPOSE

The tumor-associated auto-antigen p53 is commonly overexpressed in various types of human cancer, including colorectal cancer. Experiments in preclinical models have shown that it can serve as a target for T-cell-mediated tumor-eradication. The feasibility of a p53-specific therapeutic vaccination was investigated in cancer patients.

EXPERIMENTAL DESIGN

A Phase I/II dose-escalation study was performed that evaluated the effect of a recombinant canarypoxvirus (ALVAC) vaccine encoding wild-type human p53 in 15 patients with advanced colorectal cancer. Each group of five patients received three i.v. doses of one-tenth of a dose, one-third of a dose, or 1 dose of the vaccine [1 dose = 1 x 10(7.5) cell culture infectious dosis (CCID)50].

RESULTS

Potent T-cell and IgG antibody responses against the vector component of the ALVAC vaccine were induced in the majority of the patients. Enzyme-linked immunosorbent-spot assay (ELISPOT) analysis of vaccine-induced immunity revealed the presence of IFN-gamma-secreting T cells against both ALVAC and p53, whereas no significant interleukin-4 responses were detected. Vaccine-mediated enhancement of p53-specific T-cell immunity was found in two patients in the highest-vaccine-dose group.

CONCLUSIONS

This study demonstrated the feasibility, even in patients with advanced cancer, to elicit immune responses against the ubiquitously expressed tumor-associated auto-antigen p53. Our results form the basis for additional studies that will explore the antitumor capacity of p53 containing multivalent vaccines in cancer patients with limited tumor burden.

Effect of chromium tripicolinate supplementation on porcine immune response during the periparturient and neonatal period

A total of 36 gilts were used to assess the effects of Cr tripicolinate supplementation on immune response in sows and their offspring during the periparturient and neonatal period. Gilts were raised from weaning to reproductive age on diets with either 0 (-Cr) or 200 (+Cr) ppb supplemental Cr from CrPic. Subsequently, 22 gilts (9 -Cr and 13 +Cr) in parity 1 and 16 sows in parity 2 (7 -Cr and 9 +Cr) underwent immune status testing. Only sows that completed all procedures in parity 1 were included in parity 2. Sows were immunized with ovalbumin about 3 wk (d 0), and again 14 d later for gilts, prior to anticipated farrowing, and serum was collected on d 0 and at 14-d intervals for a total of four samples. Serum was collected from five to six pigs/litter at 24 h after birth, three or six pigs/litter the day after weaning (25 d of age) in parity 1, and three pigs/litter the day of weaning (20 d of age) in parity 2. Milk was collected at 1 h (colostrum), 6.5 d (early), and 19 d (late) after farrowing. The only effect of Cr on total immunoglobulin (Ig) concentration was on sow serum IgG (21.7 and 24.1 mg/mL for -Cr and +Cr, respectively; P = 0.08) and IgM (11.0 and 12.5 mg/mL; P = 0.06) on d 0. No effect (P > 0.15) of Cr was observed on the IgG antibody response to ovalbumin, but Cr was associated (P < 0.10) with a decreased IgM antibody response to ovalbumin beginning on d 14. In parity 2, colostral total IgG increased (80.6 and 92.4 mg/mL for parity 1 and 2, respectively; P = 0.06), which was reflected in the neonates at 24 h after birth (33.6 and 39.7 mg/mL; P = 0.01) and at weaning (7.3 and 13.3 mg/mL; P < 0.001). Supplementation of Cr tripicolinate had minimal effects on humoral antibody response of the dam or its transfer to the neonate; however, parity greatly influenced the concentrations of immunoglobulins in the milk and their transfer to the neonate.

Fludarabine therapy in Waldenström's macroglobulinemia patients treated previously with 2-chlorodeoxyadenosine

Six patients with Waldenström's macroglobulinemia (WM) resistant to previous 2-chlorodeoxyadenosine (2-CdA) therapy were treated with fludarabine. Both initial and subsequent therapy was administered according to the most widely used protocols. The median number of 2-CdA cycles given to the patients was 3.7 (range 2-5), while fludarabine was 1.7 (range 1-2). As a result partial remission was achieved in two patients and stabilization of the disease in the remaining four in spite of the inadequate response or progressive disease after 2-CdA therapy. Median monoclonal IgM concentration fell from 29.4 (range 11.6-37.1) to 16.4 g/l (range 3.8-29.1). At the same time hemoglobin concentration increased from median 114 (range 89-129) to 122 g/l (range 97-133). Side effects consisted of neutropenia (three patients) and thrombocytopenia (two patients). Two patients are alive with progression of the disease noted after 12 and 21 months of observation. One patient died as the result of cardiac disease, two others died of infection 5 and 16 months after cessation of therapy in the course of disease progression. The remaining patient was lost to follow-up after 10 months of observation with continuous stabilization. Our observations suggest that in WM patients resistant to 2-CdA, stabilization of the disease or even remission can be obtained with fludarabine.

Anti-endometrial IgM autoantibodies in endometriotic patients: a preliminary study

Japanese herbal medicines (Kampo medicines) are usually the third most popular choice among medicines for treatment of endometriosis in Japan. This traditional therapy is used to improve various signs and symptoms of endometriosis without decreasing serum estradiol levels or causing menstrual disorders. We used flow cytometry to examine and compare the effects of the Kampo therapy and danazol on anti-endometrial humoral immunity. Autoantibodies against endometrial epithelial cell lines and endometrial stromal cells were detectable in all the examined sera of men and women irrespective of the presence of endometriosis. Moreover, no significant increase in anti-endometrial antibodies was found in endometriotic patients. Anti-endometrial antibodies included Ig-gamma chain, Ig-mu chain, Ig-kappa chain, and Ig-lambda chain indicating polyclonal B cell activation in the endometriotic patients. Absorption tests of nonspecific antibodies with cervical cancer cells or ovarian cancer cells revealed that endometriotic patients had higher levels of endometrium-specific autoantibodies than did non-endometriotic healthy women. IgM fractions from endometriotic patients and healthy women differed in their effect on growth of endometrial adenocarcinoma cells. Therapy with the herbal compounds Keishi-bukuryo-gan but not danazol therapy, gradually decreased the tissue-specific anti-endometrial IgM antibody levels. These results indicate that tissue-specific anti-endometrial IgM may be a useful therapeutic marker for endometriotic patients treated with Keishi-bukuryo-gan and that endometrial tissue-specific immune disorders play specific roles in the pathogenesis or development of endometriosis.

Oxymetholone modulates cell-mediated immunity in male B6C3F1 mice

Oxymetholone is a synthetic androgen, structurally related to testosterone. It is currently used to treat anemias, but has also been abused as a performance enhancing anabolic steroid by the sport community. Concern about its suspected immunomodulatory properties provided the incentive for a detailed investigation into its effects on the mammalian immune system. In this study, male B6C3F1 mice were treated for 14 d with oxymetholone (0, 50, 150, and 300 mg/kg) by gastric intubation, then evaluated for immunotoxicity using a panel of immunotoxicity assays. Except for an increasing trend in kidney and liver weights, and a dose-dependent increase in serum blood urea nitrogen levels, no other signs of systemic toxicity were observed. Bone marrow DNA synthesis was reduced, though this did not translate into alterations in myeloid or monocyte colony forming units. Spleen B and T cell numbers, antibody response to sheep red blood cells, proliferative response to both mitogen and immunoglobulin receptor immunogens, and NK cell activity were all unaltered in mice treated with oxymetholone. Peritoneal macrophage activity was also unaffected by oxymetholone treatment. A 38% decrease in the spleen cell mixed leukocyte response, and a 15% decrease in cytotoxic T cell activity, measured in the highest oxymetholone treatment group, indicate that cell-mediated immunity was impaired following exposure. This immunomodulation did not however, translate into a change in host resistance to Listeria monocytogenes.

Glycoinositolphospholipids from Trypanosoma cruzi induce B cell hyper-responsiveness in vivo

The surface of the protozoan Trypanosoma cruzi, the etiologic agent of Chagas' disease, is covered by a dense glycolipid layer, composed mainly by a structurally related family of glycoinositolphospholipids (GIPLs). In the present study we evaluated the in vivo effects of the GIPL on B cell function and immunoglobulin (Ig) secretion. We observed that GIPL injection led to a sustained increase in circulating IgM levels. B cells from GIPL injected mice showed higher response when activated in vitro with either LPS or dextran-conjugated anti-IgD antibodies or purified cytokines. GIPL purified from T. cruzi also showed an adjuvant effect, since this glycophospholipid boosted a polysaccharide-(TNP-Ficoll) induced IgG response. Taken together, our data indicate that T. cruzi-derived GIPL could be at least partially responsible for the remarkable B cell activation observed during T. cruzi acute infection in vivo.

Vaccination of high-risk breast cancer patients with mucin-1 (MUC1) keyhole limpet hemocyanin conjugate plus QS-21

Our objective was to determine whether an immune response can be generated against MUC1 peptide and against tumor cell MUC1 after vaccination with MUC1-keyhole limpet hemocyanin (KLH) conjugate plus QS-21 in breast cancer patients. Nine patients with a history of breast cancer but without evidence of disease were treated with MUC1-KLH conjugate plus QS-21, containing 100 microg of MUC1 and 100 microg of QS-21. s.c. vaccinations were administered at weeks 1, 2, 3, 7, and 19. Peripheral blood was drawn at frequent intervals to assess antibody titers. Skin tests were placed at weeks 1, 3, 9, and 21 to determine delayed type hypersensitivity reactions. Common toxicities included a local skin reaction at the site of the vaccine, usually of 4-5 days' duration, and mild flu-like symptoms usually of 1-2 days' duration. High IgM and IgG antibody titers against synthetic MUC1 were detected. IgG antibody titers remain elevated from a minimum of 106-137 weeks after the first vaccination. Binding of IgM antibody to MCF-7 tumor cells was observed in seven patients, although there was minimal binding of IgG antibody. Two patients developed significant antibody titers post-high-dose chemotherapy and stem cell reinfusion. There was no evidence of T cell activation. This MUC1-KLH conjugate plus QS-21 was immunogenic and well tolerated in breast cancer patients. Additional trials are ongoing to determine the optimal MUC1 peptide for use in larger clinical trials. Further investigation of vaccine therapy in high-risk breast cancer is warranted.

A role for complement in the rejection of porcine ventral mesencephalic xenografts in a rat model of Parkinson's disease

Vascularized whole organ discordant xenografts placed in the periphery are rejected by a rapid "hyperacute" process that involves preformed antibody binding to the xeno-antigens on the donor endothelial cells with complement activation. In the CNS, xenografts are classically thought to be rejected more slowly by a T-cell-dependent process. We now report that xenografts of embryonic porcine ventral mesencephalic tissue in the 6-hydroxydopamine-lesioned, nonimmunosuppressed rat induce both a humoral and a cell-mediated response. Over the first 10 d after implantation, the xenografts matured with identifiable TH neurons and pig-specific neurofilament fibers extending along host white matter tracts. During this period of time, IgM and complement binding were observed within the graft, as well as a CD8 cellular infiltrate, leading to rejection of the transplant over the next 25 d. These intracerebral xenografts were not associated with an early systemic antibody response. A role for complement in this rejection process was further investigated using cobra venom factor (CVF), which systemically depleted the rats of complement for 7 d. CVF treatment, when given in the period immediately before and after grafting, delayed but did not prevent the cellular immune response induced by the graft, demonstrating that xenografted neural tissue can activate the humoral arm of the rejection process, in particular the complement cascade. This suggests that interventions targeting this aspect of the immune rejection process may be of great importance for the future development of xenotransplantation for neurodegenerative conditions.

Induction of antibodies against GM2 ganglioside by immunizing melanoma patients using GM2-keyhole limpet hemocyanin + QS21 vaccine: a dose-response study

In a previous randomized Phase III trial (P. O. Livingston et al, J. Clin. Oncol., 12: 1036-1044, 1994), we demonstrated that immunization with GM2 and bacille Calmette-Guerin reduced the risk of relapse in stage III melanoma patients who were free of disease after surgical resection and who had no preexisting anti-GM2 antibodies. That vaccine formulation induced IgM anti-GM2 antibodies in 74% but induced IgG anti-GM2 antibodies in only 10% of the patients. To optimize the immune response against GM2, a reformulated vaccine was produced conjugating GM2 to keyhole limpet hemocyanin (KLH) and using the adjuvant QS21 (GM2-KLH/QS21). In pilot studies, 70 microg of vaccine induced IgG anti-GM2 antibodies in 76% of the patients. We wished to define the lowest vaccine dose that induced consistent, high-titer IgM and IgG antibodies against GM2. Fifty-two melanoma patients who were free of disease after resection but at high risk for relapse were immunized with GM2-KLH/QS21 vaccine at GM2 doses of 1, 3, 10, 30, or 70 ILg on weeks 1, 2, 3, 4, 12, 24, and 36. Serum collected at frequent and defined intervals was tested for anti-GM2 antibodies. Overall, 88% of the patients developed IgM anti-GM2 antibodies; 71% also developed IgG anti-GM2 antibodies. GM2-KLH doses of 3-70 microg seemed to be equivalent in terms of peak titers and induction of anti-GM2 antibodies. At the 30-microg dose level, 50% of the patients developed complement fixing anti-GM2 antibodies detectable at a serum dilution of 1:10. We conclude that the GM2-KLH/QS21 formulation is more immunogenic than our previous formulation and that 3 microg is the lowest dose that induces consistent, high-titer IgM and IgG antibodies against GM2.

Immune deviation following stress odor exposure: role of endogenous opioids

Olfactory cues can alter immune function. BALB/c mice exposed to odors produced by footshock stressed donor mice have increased antibody responses and increased splenic interleukin (IL)-4 production following immunization relative to recipients of odors from unstressed animals. Here we document that exposure to stress odors results in analgesia that is blocked by the non-selective opioid receptor antagonist naltrexone. The stress odor-induced increase in antigen-driven IL-4 and antibody is also blocked by oral administration of naltrexone. Thus, we provide evidence that immune deviation can occur following a psychosocial stressor, and that the deviation appears to be mediated by endogenous opioid production.

Inhibition of human B cell activation by a novel nonsteroidal anti-inflammatory drug, indometacin famesil

Indometacin farnesil (INF) is a prodrug of indomethacin (IND) designed to reduce the occurrence of side-effects by esterification of the carboxyl group on IND with farnesol. Previous studies have shown that INF has the characteristics of disease-modifying anti-rheumatic drug (DMARD) in that it has a component of slow-acting effect in treatment of rheumatoid arthritis (RA), in which abnormal B cell functions are considered to be involved. The current studies therefore examined the effects of INF on human B cells. Ig production was induced from highly purified B cells obtained from healthy donors by stimulation with Staphylococcus aureus Cowan I (SA) plus IL-2. T cell proliferation and IFN-gamma production were induced from highly purified T cells by stimulation with immobilized mAb to CD3. At pharmacologically attainable concentrations, INF, but not IND, suppressed the production of IgM and IgG of B cells, whereas neither suppressed the T cell proliferation and IFN-gamma production. The inhibition of Ig production by INF is not due to its IND structure, but is most likely due to its farnesil component, since farnesol alone comparably suppressed the Ig production. INF and farnesol did not suppress the expression of early activation markers, including CD98, CD25, and CD71, on SA-stimulated B cells, but appeared to inhibit the maturation of B cells following the initial activation. These results indicate that INF preferentially suppresses the human B cell functions. Thus, the data suggest that INF may have more beneficial effects than IND in treatment of RA.

Detection of immunotoxicity of benzo[a]pyrene in a subacute toxicity study after oral exposure in rats

In an extended OECD 407 study protocol, including immune parameters, male Riv:Tox Wistar SPF rats were treated for 35 days with benzo[a]pyrene (B[a]p) (3, 10, 30, or 90 mg/kg body weight) by gavage. Oral administration of B[a]p in rats resulted not only in general toxicity, as indicated by the effects on body weight, but also in immunotoxicity, as indicated by the effects on bone marrow, thymus, spleen, and lymph nodes. Oral B[a]p induced a dose-related decrease in thymus weight (at 10, 30, and 90-mg/kg). Lymph node weights (popliteal, mandibular, and mesenteric) were decreased in the 90-mg/kg rats only. Histologically, indications for cortical atrophy were noted in the thymuses of the 30- and 90-mg/kg dose groups, which was confirmed by morphometric analysis. Nucleated spleen and bone marrow cell counts were decreased in the 90-mg/kg group. Both the absolute number (90 mg/kg) and relative number (10, 30, and 90 mg/kg) of B cells in the spleen were decreased. Red blood cell (RBC) and white blood cell (WBC) counts were significantly decreased; for the WBC at 90 mg/kg, and for the RBC at 10, 30, and 90 mg/kg. The absolute number of lymphocytes and eosinophilic granulocytes was decreased in the 90-mg/kg group, while the absolute number of monocytes was increased in the 10- and 30-mg/kg dose groups. Serum immunoglobulin levels showed a decrease of IgM and IgA after treatment of the animals with 30 and 90 mg/kg, respectively. The highest dose of B[a]p treatment (90 mg/kg) resulted in a significant decrease of natural killer (NK)-cell activity in the spleen. Most toxic effects were only observed in the highest-dose group (90 mg/kg), but compared to the general toxicity, some parameters indicating immunotoxic effects were also affected at lower doses (10 and 30 mg/kg). In conclusion, immunotoxicity of B[a]p can be detected using parameters of the immune system such as described in the recently updated OECD 407 guideline. In the present study thymus weight changed and spleen B-cell populations were affected at a dose of 10 mg/kg, a level where no overt general toxicity was noted.

Second generation effects of maternal ethanol consumption on immunity to Trichinella spiralis in female rats

The deleterious effects of maternal ethanol consumption on neonatal immune development and early immune responses has been well documented. However, the effects of such neonatal exposure to maternally consumed ethanol on the neonates' immune responses in their adult life, especially in combination with additional ethanol exposure, has received little attention. For these experiments, female rats were fed on either 6% ethanol or pair-fed isocaloric control Lieber-DeCarli liquid diets for 30 days prior to, and during, pregnancy and lactation. One day after weaning their pups, the mothers were infected with 1000 Trichinella spiralis larvae, and maintained on diets for an additional 20 days. At this time, they were challenged with 2000 T. spiralis larvae, killed 3 days later, and their immune status determined. These animals served as the first generation alcohol animals. Their female offspring served as the experimental second generation animals. These animals received maternal ethanol during pregnancy and lactation and control diet during their juvenile period (from weaning to 90 days of age). They were then subjected to a schedule of ethanol or pairfeeding, identical to the first generation dams. Two groups of second generation animals were established: Group 1 was exposed to ethanol during their dam's pregnancy and lactation periods only, with no subsequent ethanol treatment; Group 2 received ethanol during their dam's pregnancy and lactation periods and then again throughout their adult experimental period. Our previous studies showed only minimal changes following a secondary challenge in T. spiralis-immunized rats; however, neonates born to alcohol-consuming mothers did show some depressed secondary immune responses when challenged soon after weaning. We chose to use a secondary immune challenge to assess further immune alterations in second generation adult animals. No differences between any of the ethanol and pair-fed groups were observed in intestinal worm burdens, which is similar to data previously reported for adult alcohol-consuming animals. However, second generation group 2 animals demonstrated significantly reduced proliferation responses to T. spiralis antigen and Concanavalin A (Con A) stimulation relative to the ethanol first generation and to the second generation Group 1 animals. This group also demonstrated significantly lower absorbencies in the ELISA assay for specific IgM and IgG anti-T. spiralis antibodies than the pair-fed, ethanol first and second generation Group 1 animals. The proportion of total T cells and cytotoxic T cells was significantly lower and the proportion of natural killer cells was elevated in both second generation ethanol Groups 1 and 2 relative to the ethanol first generation and pair-fed groups. In addition, Group 2 second generation animals showed significantly lower proportions of total leukocytes and T cells than Group 1 second generation animals. Although secondary immune responses to T. spiralis infection were not altered in rats exposed to ethanol only as adults, exposure to maternal ethanol does affect some specific immune responses in second generation adult life and maternal exposure may exert cumulative immune effects in concert with later consumption of ethanol by offspring born to alcoholic mothers.

Effect of chlorpyrifos on immune function in rats

A commercial formulation of chlorpyrifos was evaluated for effects on selected immune system functions in male Fisher 344 rats. Chlorpyrifos in an olive oil vehicle was administered by oral gavage twice weekly for 28 d at a dose of 5.0 mg/kg for each treatment. Body weight and organ/body weight ratios were unaffected by the chlorpyrifos. In contrast, chlorpyrifos impaired T-lymphocyte blastogenesis induced by concanavalin A (P = 0.03) and phytohemagglutinin (P = 0.023), but did not alter B-lymphocyte blastogenesis induced by lipopolysaccharide/dextran (P = 0.082. Humoral immunity (anti-sheep red blood cell), a T-lymphocyte macrophage-dependent response, was also reduced (P = 0.019) when the antibody response was expressed/10(6) spleen cells, although the response expressed/spleen was unaffected (P = 0.32), reflecting increased lymphocyte production. The total splenic lymphocyte counts in the chlorpyrifos-treated rats increased by 91% (P < 0.0001), therefore reducing the antibody response when expressed/10(6) spleen cells. Chlorpyrifos had no effect on macrophage phagocytosis (P = 0.27), but increased the relative percentage expression of CD5+ (P = 0.028) and CD8+ (P = 0.003). The presence of normal antibody and phagocytic responses in association with reduced T-lymphocyte blastogenesis and enhanced expression of specific cell surface antigens indicated that chlorpyrifos induced immune alterations associated with lymphocyte subpopulations.

Toxicological consequences of feeding PCB congeners to infant rhesus (Macaca mulatta) and cynomolgus (Macaca fascicularis) monkeys

In a study designed to minimize interspecies extrapolation of toxicological data, nine rhesus (Macaca mulatta) and 15 cynomolgus (M. fascicularis) day-old infant monkeys were separated from their dams following parturition and hand-reared using a liquid non-human primate formulation. The infants were randomly divided into a control and a treated group which received a mixture of polychlorinated biphenyl (PCB) congeners analogous to those found in breast milk from Canadian women. The concentration of congeners in the dosing media resulted in each infant receiving a total of 7.5 microg PCB congeners/kg body weight/day. The congeners were added either to the liquid formulation or to corn oil and administered to the back of the monkey's mouth for 20 weeks. Monthly blood and adipose specimens were obtained during the dosing period and then periodically until the monkey was necropsied or taken off test (minimum of 66 weeks on test) for congener analysis. Parameters such as body weight, formula consumption, tooth eruption, somatic measurements, haematology and serum biochemistry were monitored throughout the study. In addition, a qualitative evaluation of the absorption and depletion of the various congeners was undertaken as was an immunological evaluation. For the monitored parameters, very few differences were found to be statistically significant. For the immunological parameters, the only statistically differences found were a reduction over time for immunoglobulins M and G antibodies to sheep red blood cells (cyno, P = 0.025; rhesus, P = 0.002) and a treatment-related reduction in the levels of the HLA-DR cell surface marker (mean percent, P = 0.016; absolute levels, P = 0.027). There were some qualitative differences regarding absorption and depletion rates for the various congeners, but it could not be definitely ascertained whether these differences were due to species differences or dosing mode. However, statistically significant differences were found for treatment (P = 0.0293) as well as for species and vehicle regarding the concentration of PCB in blood (species;--P = 0.0399; treatment--P = 0.0001) and adipose tissue (species--P = 0.0489; treatment--P = 0.0001).

Effects of Brazilin on induction of immunological tolerance by sheep red blood cells in C57BL/6 female mice

Brazilin was examined for its effects on the induction of immunological tolerance. Brazilin was administered to C57BL/6 female mice for 2 consecutive days before the immunization with high dose SRBC (10(9) cells) which can produce immunological tolerance. Delayed type hypersensitivity, IgM plaque forming cells, ConA induced IL-2 production and mitogen- or antigen-induced proliferation of lymphocytes were measured as evaluation parameters. Administration of brazilin prior to immunization could keep the DTH and IL-2 production almost optimally immunized levels. Brazilin also inhibited the elevation of non-specific suppressor cell activity. ConA induced proliferation of splenocytes in high dose SRBC immunized mice was significantly decreased by pretreatment of brazilin. And this might be one of the reason for augmentation of DTH by brazilin. However, IgM plaque forming cells were not affected by the treatment of brazilin. These results indicate that brazilin prevents the induction of immunological tolerance caused by high dose SRBC by suppressing the elevation of suppressor cell activity and by inhibiting the decrease in IL-2 production in C57BL/6 female mice.

Effect of supplementation with chromium picolinate on antibody titers to 5-hydroxymethyl uracil

Recent in vitro studies have shown that chromium (III) compounds such as chromium picolinate, a popular dietary supplement among people trying to lose weight, produce chromosome damage. We monitored levels of DNA damage in a chromium picolinate supplement trial by measuring antibodies titers to an oxidized DNA base, 5-hydroxymethyl-2'-deoxyuridine (HMdU), by enzyme-linked immunosorbent assays. Ten obese volunteer women completed a 8-week course of 400 micrograms chromium picolinate per day. In either absolute titers or percent of the baseline value, there were no changes in antibody titers at 4 or 8 weeks. The titers were very stable within individuals and those of one individual rarely crossed over others, which was reflected in an intraclass correlation coefficient of 0.99 (95% confidence interval: 0.96-1.00). There were no effects on glucose and lipid metabolism in this period. The results of this trial suggest that chromium (III) picolinate in a dose typically used for nutrient supplementation dose not increase oxidative DNA damage, as measured by anti-HMdU antibody levels.

Low stimulation of peripheral lymphocytes, following in vitro application of Emdogain

Fast tissue regeneration after therapeutic manipulations is a central problem of periodontology, oral surgery and trauma of the periodontal tissues, including bone. Several products, which augment tissue regeneration, have been manufactured and assayed in clinical practice with positive results. Emdogain is a recent addition in this field, as a tissue-regenerating product. The substance is a derivative of amelogenin, obtained from porcine embryonic tissues. At the present time, it is not known whether the substance can induce a local (due to the uptake of the substance) or systemic immune response. The aim of the present study was to evaluate, in vitro, the ability of Emdogain to influence, in vitro, the immune system. Peripheral blood lymphocytes, isolated for 10 healthy donors, were cultured in the presence of various concentrations of the substance, in order to determine the rate of cell proliferation, the expression of surface antigens and the production of cytokines and immunoglobulins. Under our experimental conditions, Emdogain produced a slight increase of the proliferation of lymphocytes, restricted to the CD25 (IL-2 receptor) fraction of the CD4 positive T-lymphocytes, and a concomitant decrease of CD19 positive B-lymphocytes. Other cell fractions (CD8 positive T-cells, B-cells and NK-cells) were not affected. Under our conditions too, immunoglobulin and cytokin (IL-2 and IL-6) production was not modified, even after a 3-day application of concentrations much higher than those used in clinical practice. Our data suggest that Emdogain slightly induce an immune response, restricted to the activated fraction of CD4 T-lymphocytes in vitro.

Efficient in vitro model for immunotoxicologic assessment of mammary silicone implants

In clinical and experimental studies, silicone gel has been assumed to cause immune alterations that may be related to macrophage activation of silicone implants. However, it has not been proven that the immunotoxicities are caused by the direct contact of macrophages and silicone gel because there has not been an adequate experimental model. In the present study, silicone gel was loaded directly onto Petri dishes and was distributed uniformly to the bottom by centrifugation. Peritoneal macrophages and splenic lymphocytes were cultured either on the silicone-coated plates or on the conventional, normal plates, and their functions were compared with each other. The experiments were repeated three times. The cytotoxic activities of peritoneal macrophages on cancer cells were markedly augmented by cultivation on silicone gel, and the primary T-dependent immunoglobulin M response in which macrophages participated as antigen presenting cells was also enhanced by incubation on silicone gel. However, macrophage-unrelated functions mediated by B and T lymphocytes were not affected by the silicone gel treatment. It was proven that the direct contact of macrophages with silicone gel was a primary cause of acute immune activation that was related to foreign body reaction. In addition, the present in vitro model exhibited similar silicone-induced immunotoxicities in previous animal and clinical studies.