Specific immunotherapy has long-term preventive effect of seasonal and perennial asthma: 10-year follow-up on the PAT study

BACKGROUND

3-year subcutaneous specific immunotherapy (SIT) in children with seasonal allergic rhinoconjunctivitis reduced the risk of developing asthma during treatment and 2 years after discontinuation of SIT (5-year follow-up) indicating long-term preventive effect of SIT.

OBJECTIVE

We evaluated the long-term clinical effect and the preventive effect of developing asthma 7-years after termination of SIT.

METHODS

One hundred and forty-seven subjects, aged 16-25 years with grass and/or birch pollen allergy was investigated 10 years after initiation of a 3-year course of SIT with standardized allergen extracts of grass and/or birch or no SIT respectively. Conjunctival provocations were performed outside the season and methacholine bronchial provocations were performed during the season and winter. Asthma was assessed by clinical evaluation.

RESULTS

The significant improvements in rhinoconjunctivitis and conjunctival sensitivity persisted at the 10-year follow-up. Significantly less actively treated subjects had developed asthma at 10-year follow-up as evaluated by clinical symptoms [odds ratio 2.5 (1.1-5.9)]. Patients who developed asthma among controls were 24/53 and in the SIT group 16/64. The longitudinal treatment effect when adjusted for bronchial hyper-responsiveness and asthma status at baseline including all observations at 3, 5 and 10 years follow-up (children with or without asthma at baseline, n = 189; 511 observations) was statistically significant (P = 0.0075). The odds ratio for no-asthma was 4.6 95% CI (1.5-13.7) in favor of SIT.

CONCLUSION

A 3-year course of SIT with standardized allergen extracts has shown long-term clinical effects and the potential of preventing development of asthma in children with allergic rhinoconjunctivitis up to 7 years after treatment.

CLINICAL IMPLICATION

Specific immunotherapy has long-term clinical effects and the potential of preventing development of asthma in children with allergic rhino conjunctivitis up to 7 years after treatment termination.

Preparation of corn (Zea mays) peptides and their protective effect against alcohol-induced acute hepatic injury in NH mice

CPS [corn (Zea mays) peptides] were prepared from corn gluten meal by proteolysis with alcalase, an alkaline protease. The molecular-mass distribution of CPS is from 200 to 1000 Da as determined by MS. The amino acid composition of CPS was also analysed by HPLC. CPS contains almost no free amino acids. The protective effect of CPS against acute hepatic injuries induced by alcohol was verified in NH mice that were fed with different dosages of CPS for 30 days and subsequently given an acute dose of alcohol orally. As a result, CPS reduced both hepatic malondialdehyde and triacylglycerol levels, along with enhanced hepatic GSH (glutathione) levels, relative to the control. Hepatic histological changes were also observed. The result indicates that CPS is capable of attenuating ethanol-induced hepatic injury. The effect of CPS on removing superoxide anion in vitro was also studied as an additional proof that CPS is capable of abating hepatic superoxidant stress.

Prospective controlled cohort studies on long-term therapy of cervical cancer patients with a mistletoe preparation (Iscador)

BACKGROUND

Mistletoe preparations such as Iscador are commonly used in complementary medication for many cancer indications, particularly solid cancers. The efficacy of this complementary therapy is still controversial.

OBJECTIVE

Does longterm therapy with Iscador show any effect on survival, tumor progression and psychosomatic self-regulation of patients with cervical cancer?

PATIENTS AND METHODS

Prospective recruitment and long-term follow-up was carried out in 3 controlled cohort studies: In a randomized matched-pair study (19 pairs), cervical cancer patients with distant metastases and no mistletoe therapy were matched for prognostic factors. By paired random allocation, one of the patients was recommended mistletoe therapy by the attending physician. In 2 non-randomized matched-pair studies, cervical cancer patients without (102) and with (66) metastases, who already received mistletoe therapy, were matched with control patients without Iscador therapy.

RESULTS

For survival, the non-randomized studies showed significant effects in favor of Iscador therapy: hazard ratio (HR) estimate and 95% confidence interval (CI): 0.23 (0.14-0.39) and 0.37 (0.17-0.80), respectively. An effect of long-term Iscador therapy on tumor progression was not seen. Psychosomatic self-regulation in the Iscador group improved significantly within 12 months compared with the control group in the randomized as well as in 1 non-randomized study (cervical cancer without metastases): estimate of the median difference and 95% CI: 0.70 (0.15-1.05) and 0.25 (0.15-0.35), respectively.

CONCLUSION

Iscador may have the effect of prolonging overall survival of cervical cancer patients. In the short term, psychosomatic self-regulation increases more markedly under complementary Iscador therapy than under conventional therapy alone.

Grass pollen immunotherapy induces an allergen-specific IgA2 antibody response associated with mucosal TGF-beta expression

Allergen immunotherapy (IT) has long-term efficacy in IgE-mediated allergic rhinitis and asthma. IT has been shown to modify lymphocyte responses to allergen, inducing IL-10 production and IgG Abs. In contrast, a putative role for IgA and local TGF-beta-producing cells remains to be determined. In 44 patients with seasonal rhinitis/asthma, serum IgA1, IgA2, and polymeric (J chain-containing) Abs to the major allergen Phl p 5 were determined by ELISA before and after a 2-year double-blind trial of grass pollen (Phleum pratense) injection IT. Nasal TGF-beta expression was assessed by in situ hybridization. Sera from five IT patients were fractionated for functional analysis of the effects of IgA and IgG Abs on IL-10 production by blood monocytes and allergen-IgE binding to B cells. Serum Phl p 5-specific IgA2 Abs increased after a 2-year treatment (approximately 8-fold increase, p = 0.002) in contrast to IgA1. Increases in polymeric Abs to Phl p 5 (approximately 2-fold increase, p = 0.02) and in nasal TGF-beta mRNA (p = 0.05) were also observed, and TGF-beta mRNA correlated with serum Phl p 5 IgA2 (r = 0.61, p = 0.009). Post-IT IgA fractions triggered IL-10 secretion by monocytes while not inhibiting allergen-IgE binding to B cells as observed with IgG fractions. This study shows for the first time that the IgA response to IT is selective for IgA2, correlates with increased local TGF-beta expression, and induces monocyte IL-10 expression, suggesting that IgA Abs could thereby contribute to the tolerance developed in IT-treated allergic patients.

[Influence of ML-1 standardized mistletoe extract on the quality of life in head and neck cancer patients]

BACKGROUND

ML-1 standardized mistletoe extracts have been recommended for increasing the health-related quality of life in cancer patients.

PATIENTS AND METHODS

The EORTC questionnaire QLQ-C30((V2)) was given to a randomly chosen subgroup of 399 patients of a prospective, randomized, open, multi-center trial. A total of 200 patients from this trial were randomized for ML-1 treatment (1 ng/kg body weight ML-1 was injected subcutaneously twice weekly over a 60-week period. Treatment cycles of 12 weeks were followed by a break of 4 weeks (between weeks 12-16, 28-32, and 44-48)). The remaining 199 patients formed the control group.

RESULTS

Patients completed questionnaires before the start of their treatments at week 0 and continued until week 156. The compliance rate was high: 3611 questionnaires were available, which equals a median of nine longitudinal measurements per patient between weeks 0 and 156. Analysis did not indicate any improvement in the quality of life for either group. A significant decrease in quality of life, however, was seen in patients undergoing radiotherapy. In these patients, the global state of health was reduced and four symptom scales were significantly worse.

CONCLUSION

Our results demonstrated no improvement in the quality of life in head and neck cancer patients when treated with ML-1 extract.

Beneficial effects of a plant histaminase in a rat model of splanchnic artery occlusion and reperfusion

Splanchnic artery occlusion (SAO) followed by reperfusion causes endothelial injury and inflammation which contribute to the pathophysiology of shock. We investigated the effects of pea seedling (Latyrus cicera) histaminase, known to afford protection against the deleterious effects of cardiac ischemia/reperfusion, given to rats subjected to SAO/reperfusion-induced splanchnic injury. Histaminase (80 IU kg, 15 min before reperfusion) significantly reduced the drop of blood pressure and high mortality rate caused by SAO/reperfusion. Histaminase also reduced histopathological changes, leukocyte infiltration (myeloperoxidase), and expression of endothelial cell adhesion molecules in the ileum. Histaminase counteracted free radical-mediated tissue injury, as judged by a significant decrease in the plasma and tissue levels of peroxidation and nitration products (oxidized rhodamine, malondialdehyde, nitrotyrosine), DNA damage markers (8-hydroxy-2'-deoxyguanosine, poly-adenosine diphosphate-ribosylated DNA) and consumption of tissue antioxidant enzymes (superoxide dismutase). As a result, histaminase led to a reduction of ileal cell apoptosis (caspase 3, terminal deoxynucleotidyltransferase-mediated UTP end labeling-positive cells). These results show that histaminase exerts a clear-cut protective effect in SAO/reperfusion-induced splanchnic injury, likely caused by oxidative catabolism of proinflammatory histamine and antioxidant effects resulting in hindrance of free radical-mediated tissue injury, endothelial dysfunction, and leukocyte recruitment. Thus, histaminase could be used therapeutically in intestinal ischemia.

Deficiency in thrombin-activatable fibrinolysis inhibitor (TAFI) protected mice from ferric chloride-induced vena cava thrombosis

Thrombin-activatable fibrinolysis inhibitor (TAFI) is a plasma carboxypeptidase that renders a fibrin-containing thrombus less sensitive to lysis. Since the role of TAFI in thrombus formation is still controversial in mice, our present study was designed to evaluate mice deficient in TAFI (TAFI(-/-)) on FeCl(3)-induced vena cava and carotid artery thrombosis. Parallel studies were carried out in wild-type mice using a potato carboxypeptidase inhibitor (PCI), a selective inhibitor of activated TAFI (TAFIa). Significant reduction in thrombus formation was observed in TAFI(-/-) mice (n = 8, P < 0.05 compared to wild-type littermates) but not in heterozygous (TAFI(+/-)) mice in 3.5% FeCl(3)-induced vena cava thrombosis. A similar effect was observed following treatment with 5 mg/kg bolus plus 5 mg/kg/h PCI in the same venous thrombosis model in C57BL/6 mice (n = 8, P < 0.01 compared to vehicle). No compositional difference was observed for the venous thrombi in TAFI(-/-) and wild-type littermates with or without PCI treatment using histological assessment. In contrast, neither TAFI deficiency nor treatment with PCI showed antithrombotic efficacy in the 3.5% FeCl(3)-induced carotid artery thrombosis model. In a tail transection bleeding time model, both TAFI deficiency and PCI treatment increased bleeding time up to 4.5 and 3.5 times, respectively, over controls (P < 0.05, n = 8). Similar ex vivo fibrinolytic activities were demonstrated for both TAFI deficiency and PCI treatment as enhanced lysis of thrombin-induced plasma clots and lysis of whole blood clot in a thrombelastograph. These data provide direct evidence for the role of TAFIa in vena cava thrombosis without the addition of exogenous thrombolytic in mice. The strong ex vivo fibrinolytic activity of TAFI deficiency or TAFIa inhibition by PCI provides a biomarker of TAFIa inhibition that tracks in vivo antithrombotic efficacy.

Multimodality molecular imaging of glioblastoma growth inhibition with vasculature-targeting fusion toxin VEGF121/rGel

Vascular endothelial growth factor A (VEGF-A) and its receptors, Flt-1/FLT-1 (VEGFR-1) and Flk-1/KDR (VEGFR-2), are key regulators of tumor angiogenesis and tumor growth. The purpose of this study was to determine the antiangiogenic and antitumor efficacies of a vasculature-targeting fusion toxin (VEGF(121)/rGel) composed of the VEGF-A isoform VEGF(121) linked with a G(4)S tether to recombinant plant toxin gelonin (rGel) in an orthotopic glioblastoma mouse model by use of noninvasive in vivo bioluminescence imaging (BLI), MRI, and PET.

METHODS

Tumor-bearing mice were randomized into 2 groups and balanced according to BLI and MRI signals. PET with (64)Cu-1,4,7,10-tetraazacyclododedane-N,N',N'',N'''-tetraacetic acid (DOTA)-VEGF(121)/rGel was performed before VEGF(121)/rGel treatment. (18)F-Fluorothymidine ((18)F-FLT) scans were obtained before and after treatment to evaluate VEGF(121)/rGel therapeutic efficacy. In vivo results were confirmed with ex vivo histologic and immunohistochemical analyses.

RESULTS

Logarithmic transformation of peak BLI tumor signal intensity revealed a strong correlation with MRI tumor volume (r = 0.89, n = 14). PET with (64)Cu-DOTA-VEGF(121)/rGel before treatment revealed a tumor accumulation (mean +/- SD) of 11.8 +/- 2.3 percentage injected dose per gram at 18 h after injection, and the receptor specificity of the tumor accumulation was confirmed by successful blocking of the uptake in the presence of an excess amount of VEGF(121). PET with (18)F-FLT revealed significant a decrease in tumor proliferation in VEGF(121)/rGel-treated mice compared with control mice. Histologic analysis revealed specific tumor neovasculature damage after treatment with 4 doses of VEGF(121)/rGel; this damage was accompanied by a significant decrease in peak BLI tumor signal intensity.

CONCLUSION

The results of this study suggest that future clinical multimodality imaging and therapy with VEGF(121)/rGel may provide an effective means to prospectively identify patients who will benefit from VEGF(121)/rGel therapy and then stratify, personalize, and monitor treatment to obtain optimal survival outcomes.

Expression of recombinant puroindolines for the treatment of staphylococcal skin infections (acne vulgaris)

Puroindolines are antimicrobial peptides that occur in wheat seed, and are characterized by broad antimicrobial activity. We describe the heterologous expression of puroindoline A and B in the Origami strain of Escherichia coli. The recombinant puroindolines showed the same antimicrobial activity on Staphylococcus epidermidis as compared to the native peptides (MIC(90)=30microgml(-1)). The bactericidal activity was 125microgml(-1) for recombinant puroindoline A and 42microgml(-1) for recombinant puroindoline B. Neither protein shows in vitro haemolytic activity or toxicity towards the murine macrophage cell line J774, but they are able to kill intracellular staphylococci. Our preliminary results suggest that recombinant puroindolines deserve further attention as alternatives to the conventional antibiotics in the control of S. epidermidis skin infections.

An observational study on outgrowing food allergy during non-birch pollen-specific, subcutaneous immunotherapy

BACKGROUND

Birch pollen-specific immunotherapy (SIT) decreases allergy to foods containing birch pollen-homologous allergens. Cross-reactivity was also observed between plane tree pollen and some vegetable foods.

OBJECTIVE

The aim of this study was to evaluate the outgrowing of food allergy by patients suffering from vegetable food allergy associated with plane tree pollinosis (rhinoconjunctivitis and/or asthma) during plane tree pollen SIT.

METHODS

An observational and prospective study was conducted in 16 adult patients suffering from vegetable food allergy (hazelnut, walnut, lettuce, peach and cherry) and from plane tree pollinosis receiving plane tree pollen SIT for 1 year. Open oral challenges with the implicated food were performed before and after SIT. Blood samples were drawn for measurement of pollen- and food-specific IgE and IgG4 before and after treatment.

RESULTS

Plane tree SIT resulted in a significant decrease in food allergy, since the mean food quantity provoking objective symptoms increased from 2.19 to 13.74 g (p < 0.05), and 6 of the 11 patients tolerated the highest level (25 g) of the challenged food after plane tree SIT. Laboratory data also showed a decrease in IgE levels and an increase in IgG4 levels after immunotherapy.

CONCLUSION

SIT with plane tree pollen has a positive impact on food allergy in plane tree pollen-allergic subjects.

Immunotherapy with CpG DNA conjugated with T-cell epitope peptide of an allergenic Cry j 2 protein is useful for control of allergic conditions in mice

Immunotherapy using T-cell epitope peptides or CpG DNA conjugated with allergenic protein is useful, although the mechanisms of these therapies differ. However, the combination of CpG DNA and peptide, but not protein, had not been documented. Therefore, we investigated CpG DNA conjugated with peptide to obtain positive synergistic effects. In the first experiment, mice were vaccinated with a conjugate of CpG DNA and Cry j 2 T-cell epitope peptide p246-259 (CpG-peptide); a mixture of CpG DNA and peptide (CpG+peptide); peptide alone, or PBS alone, and immunized with Cry j 2. In the second experiment, mice were immunized with Cry j 2 and injected with CpG-peptide, CpG+peptide, peptide only, or PBS only. In both experiments, Cry j 2-specific IgE, IL-4, and IL-5 were significantly lower in mice given CpG-peptide, versus those given CpG+peptide, peptide alone, or PBS alone. However, IgG2a, IgG2b and IFN-gamma did not increase in mice injected with CpG-peptide. In the third experiment, CpG-peptide significantly attenuated nasal symptoms (sneezing and nasal rubbing) compared to CpG+peptide, peptide alone, or PBS alone. Mice were also injected with a conjugate of CpG DNA and Cry j 2 protein (CpG-Cry j 2) or CpG-peptide to compare prime responses. Mice vaccinated with CpG-Cry j 2 generated Cry j 2-specific IgG1, whereas those vaccinated with CpG-peptide did not produce IgG1. This study demonstrated, for the first time, that immunotherapy with CpG DNA conjugated with a T-cell peptide is useful in preventing and treating allergic conditions.

Pharming and transgenic plants

Plant represented the essence of pharmacopoeia until the beginning of the 19th century when plant-derived pharmaceuticals were partly supplanted by drugs produced by the industrial methods of chemical synthesis. In the last decades, genetic engineering has offered an alternative to chemical synthesis, using bacteria, yeasts and animal cells as factories for the production of therapeutic proteins. More recently, molecular farming has rapidly pushed towards plants among the major players in recombinant protein production systems. Indeed, therapeutic protein production is safe and extremely cost-effective in plants. Unlike microbial fermentation, plants are capable of carrying out post-translational modifications and, unlike production systems based on mammalian cell cultures, plants are devoid of human infective viruses and prions. Furthermore, a large panel of strategies and new plant expression systems are currently developed to improve the plant-made pharmaceutical's yields and quality. Recent advances in the control of post-translational maturations in transgenic plants will allow them, in the near future, to perform human-like maturations on recombinant proteins and, hence, make plant expression systems suitable alternatives to animal cell factories.

Randomised and non-randomised prospective controlled cohort studies in matched-pair design for the long-term therapy of breast cancer patients with a mistletoe preparation (Iscador): a re-analysis

OBJECTIVE

Expanded presentation and re-analysis of previously published data of randomized and non-randomized studies on mistletoe therapy with breast cancer patients [3, 4]. The main question is: Does a re-analysis confirm the previously reported effects of prolonging the survival of patients with breast cancer under long-term application of a complementary/anthroposophic therapy with the European mistletoe preparation Iscador?

DATA SOURCES

(1) Randomised matched-pairs study: Breast cancer patients with only lymphatic metastases (17 pairs) that had never used mistletoe therapy were matched for several prognostic factors. By paired random allocation, one patient of a pair received a suggestion of mistletoe therapy to be applied by the attending physician. (2) Non-randomised matched-pairs studies: Patients that had already received mistletoe (Iscador) therapy were matched to control patients from the same pool using the same prognostic criteria. Three groups were recruited by this procedure: breast cancer with local recurrences and no metastases (42 pairs), breast cancer with only lymphatic metastases (55 pairs), and breast cancer with distant metastases (83 pairs).

ANALYSIS

Cox proportional hazard models and sensitivity analyses based on subsets of the original data sets according to strict or lose application of the matching criteria.

RESULTS

The results of this re-analysis are consistent with the earlier results, even when comparing different methods and subsets. In the randomised study, the effect of long-term Iscador therapy on overall survival is significantly in favour of the Iscador therapy: Estimate of the median difference and 95 % confidence interval in years 2.5 (0.83, 4.50). The results for the non-randomised studies were also in favour of the Iscador therapy: Breast cancer with local recurrences and no metastases: estimate of hazard ratio and 95 % confidence interval 0.52 (0.23, 1.17); breast cancer with lymphatic metastases: 0.27 (0.15, 0.50); breast cancer with distant metastases: 0.53 (0.32, 0.88). As a short-term effect of this therapy, psychosomatic self-regulation noticeably increases within 3 months in the Iscador group in comparison to the control group in the randomised study: estimate of the median difference 0.90 (0, 1.75).

CONCLUSION

The re-analysis demonstrates that the effects shown in the previously published data are consistent despite using different analytic methods and different subsets. Overall, the survival of patients receiving mistletoe treatment with Iscador is longer in these studies. In the short term, psychosomatic self-regulation, as a measure of autonomous coping with the disease, rises more under Iscador therapy than under conventional therapy alone.

Protein isolate from the herb, Phyllanthus niruri L. (Euphorbiaceae), plays hepatoprotective role against carbon tetrachloride induced liver damage via its antioxidant properties

Phyllanthus niruri L. (Euphorbiaceae) (P. niruri) is a well-known hepatoprotective herbal plant. In the present study, hepatoprotective potential of the protein isolate of P. niruri was investigated against carbon tetrachloride (CCl(4)) induced liver damage in vivo. Protein isolate of P. niruri was intraperitoneally injected in mice either prior to (preventive) or after the induction of toxicity (curative). Levels of different liver marker enzymes in serum and different anti-oxidant enzymes, as well as lipid peroxidation products and glutathione (GSH) in liver homogenates were measured in normal, control (toxicity induced) and protein isolate treated mice. Administration of CCl(4) increased the serum glutamate pyruvate transaminase (GPT) and alkaline phosphatase (ALP) levels of mice sera along with increased lipid peroxidation and reduced levels of antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) in the liver. Treatment with the protein isolate of P. niruri significantly altered these changes to almost normal. The protein isolate also showed protective properties as was evidenced in histopathological studies. Results suggest that the protein isolate of P. niruri protects liver tissues against oxidative damage and somehow helps stimulating repair mechanism present in liver. It could be used as an effective hepatoprotector against CCl(4) induced liver damage.

Prospective controlled cohort studies on long-term therapy of breast cancer patients with a mistletoe preparation (Iscador)

BACKGROUND

Mistletoe preparations such as Iscador (Weleda, Schwäbisch Gmünd, Germany) are commonly used in complementary and alternative / anthroposophic medicine for many cancer indications, particularly for solid cancers. Efficacy of this complementary therapy is still controversial.

OBJECTIVE

Does long-term therapy with Iscador show any effect on survival, tumor progression and psychosomatic self-regulation of patients with breast cancer?

PATIENTS AND METHODS

Prospective recruitment and long-term follow-up of two controlled cohort studies: (1) Randomized matched-pair study (38 pairs): breast cancer patients without any recurrences or metastases and no mistletoe therapy were matched for prognostic factors. By pairwise random allocation, one of the patients was suggested mistletoe therapy to be applied by the attending physician. (2) Non-randomized matched-pair study (84 pairs): breast cancer patients without recurrences or metastases that already received mistletoe therapy were matched to control patients without Iscador therapy.

RESULTS

For overall survival, the nonrandomized study shows significant effects in favor of Iscador therapy: hazard ratio HR estimate and 95% confidence interval CI: 0.43 (0.27-0.68). The effect of long-term Iscador therapy on tumor progression as measured by the time to local recurrences, lymphatic or distant metastases in breast cancer patients without any such events at first diagnosis, is in most cases significant in favor of the Iscador group, in the randomized as well as in the non-randomized study. Psychosomatic self-regulation in the Iscador group improves significantly within 12 months compared with the control group in the randomized as well as in the non-randomized study: estimate of the median difference and 95% CI: 0.35 (0.05-0.60), respectively 0.20 (0-0.35).

CONCLUSION

Iscador shows a clinically relevant effect on breast tumor progression as measured by overall survival as well as by the time to recurrences, lymphatic or distant metastases. In the short term, psychosomatic self-regulation increases more markedly under complementary Iscador therapy than under conventional therapy alone.

PS80 interferes with the antiallergic effect of Cry-consensus peptide, a novel recombinant peptide for immunotherapy of Japanese cedar pollinosis, at very low concentration through modulation of Th1/Th2 balance

Polysorbate 80 (PS80 or Tween-80) is often used as an additive to promote the rapid solubilization of pharmaceuticals in aqueous solutions. We investigated whether coinjection of a minimal amount of PS80 had a modulatory effect on the immunotherapeutic effects of Cry (Cryptomeria)-consensus peptide, a novel peptide developed for the therapeutic management of Japanese cedar pollinosis, using a Cry j 1-sensitized mouse model with experimental allergic rhinitis. Subcutaneous challenge with Cry-consensus peptide plus 50 microg/ml of PS80 did not affect the antigen-specific proliferation of splenocytes, but decreased the potency of Cry-consensus peptide to inhibit antigen-specific interleukin (IL)-5 production by the cells significantly in comparison with challenge with Cry-consensus peptide alone. However, there was no significant difference between the effect of Cry-consensus peptide administration on interferon (IFN)-gamma production in the presence and absence of PS80, indicating that PS80 interfered with the T helper 1 (Th1)-dominant T helper balance induced by Cry-consensus peptide challenge. Moreover, the increase in the level of antigen-specific immunoglobulin G2a (IgG2a) induced by Cry-consensus peptide challenge was inhibited slightly but unambiguously by PS80 coinjection. These in vitro experiments indicated that PS80 induces Th2-type differentiation of T helper cells through preferential inhibition of IFN-gamma expression relative to IL-5 expression in splenocytes in a concentration-dependent manner. In naïve mice, sensitization by Cry-consensus peptide with PS80 induced antigen-specific IL-5 production more potently than sensitization by Cry-consensus peptide alone, and when PS80 was added to bone marrow-derived dendritic cells, the endocytosis of fluorescence-labelled Cry-consensus peptide was dramatically inhibited in a concentration-dependent manner. Therefore, we conclude that PS80 has an immunomodulatory effect on the antigen-specific response resulting in a shift towards Th2 predominance with respect to the antigen recognition stage. Taken together, our findings suggest that PS80 might decrease the efficacy of Cry-consensus peptide through modulation of the efficiency of antigen endocytosis and/or of the direction of successive T helper cell differentiation.

Ribosome-inactivating proteins: progress and problems

Ribosome-inactivating proteins (RIPs), mostly from plants, are enzymes which depurinate rRNA, thus inhibiting protein synthesis. They also depurinate other polynucleotide substrates. The biological activity of RIPs is not completely clarified, and sometimes independent of the inhibition of protein synthesis. There are differences in the cytotoxicity of RIPs and, consequently, in their toxicity to animals. Some RIPs are potent toxins, the best known being ricin, a potential biological weapon. New toxins have recently been identified. RIPs cause apoptotic and necrotic lesions, and induce production of cytokines causing inflammation. RIPs are potentially useful in agriculture and medicine because (i) they have antiviral activity and (ii) they are used for the preparation of conjugates with antibodies ('immunotoxins') or other carriers, rendering them specifically toxic to the cell target of the carrier, which may be helpful in therapy. The distribution, mechanism of action and role in nature of RIPs are not completely understood, and we can expect several future developments in their practical application.

Targeted anticancer immunotoxins and cytotoxic agents with direct killing moieties

Despite the progress of the bioinformatics approach to characterize cell-surface antigens and receptors on tumor cells, it remains difficult to generate novel cancer vaccines or neutralizing monoclonal antibody therapeutics. Among targeted cancer therapeutics, biologicals with targetable antibodies or ligands conjugated or fused to toxins or chemicals for direct cell-killing ability have been developed over the last 2 decades. These conjugated or fused chimeric proteins are termed immunotoxins or cytotoxic agents. Two agents, DAB389IL-2 (ONTAKTM) targeting the interleukin-2 receptor and CD33-calicheamicin (Mylotarg), have been approved by the FDA for cutaneous T-cell lymphoma (CTCL) and relapsed acute myeloid leukemia (AML), respectively. Such targetable agents, including RFB4(dsFv)-PE38 (BL22), IL13-PE38QQR, and Tf-CRM107, are being tested in clinical trials. Several agents using unique technology such as a cleavable adapter or immunoliposomes with antibodies are also in the preclinical stage. This review summarizes the generation, mechanism, and development of these agents. In addition, possible future directions of this therapeutic approach are discussed.

Five-year follow-up on the PAT study: specific immunotherapy and long-term prevention of asthma in children

BACKGROUND

A 3-year course of specific immunotherapy (SIT) in children with hay fever to grass and/or birch pollen significantly reduced the risk of developing asthma. To investigate the long-term preventive effect, we performed a follow up--2 years after termination of immunotherapy.

METHODS

A total of 183 children, aged 6-14 years with grass and/or birch pollen allergy could be investigated 2 years after discontinuation of SIT or no treatment. Conjunctival provocation tests (CPTs) and methacholine bronchial provocation tests were carried out during the season and winter after 5 years. The development of asthma was assessed by clinical evaluation.

RESULTS

The significant improvement in hay fever and CPT results observed after 3 years of SIT persisted at the 5-year follow-up. No difference in bronchial responsiveness to methacholine was found after 5 years because of spontaneous improvement during the follow-up period in the control patients. The immunotherapy-treated children had significantly less asthma after 5 years as evaluated by clinical symptoms [odds ratio 2.68 (1.3-5.7)] in favor of SIT for prevention of development of asthma and significantly less patients reported an increase in asthma scores (P < 0.01).

CONCLUSION

Immunotherapy for 3 years with standardized allergen extracts of grass and/or birch shows long-term clinical effect and preventive effect on development of asthma in children with seasonal rhinoconjunctivitis.

Slow acting protein extract from fruit pulp of Momordica charantia with insulin secretagogue and insulinomimetic activities

The protein from Thai bitter gourd (Momordica charantia) fruit pulp was extracted and studied for its hypoglycemic effect. Subcutaneous administration of the protein extract (5, 10 mg/kg) significantly and markedly decreased plasma glucose concentrations in both normal and streptozotocin-induced diabetic rats in a dose-dependent manner. The onset of the protein extract-induced antihyperglycemia/hypoglycemia was observed at 4 and 6 h in diabetic and normal rats, respectively. This protein extract also raised plasma insulin concentrations by 2 fold 4 h following subcutaneous administration. In perfused rat pancreas, the protein extract (10 microg/ml) increased insulin secretion, but not glucagon secretion. The increase in insulin secretion was apparent within 5 min of administration and was persistent during 30 min of administration. Furthermore, the protein extract enhanced glucose uptake into C2C12 myocytes and 3T3-L1 adipocytes. Time course experiments performed in rat adipocytes revealed that M. charantia protein extract significantly increased glucose uptake after 4 and 6 h of incubation. Thus, the M. charantia protein extract, a slow acting chemical, exerted both insulin secretagogue and insulinomimetic activities to lower blood glucose concentrations in vivo.

Lupin protein attenuates the development of hypertension and normalises the vascular function of NaCl-loaded Goto-Kakizaki rats

The beneficial cardiovascular effects of soy protein have been studied intensively in recent years. Another protein-rich legume is lupin, which has been shown to have similar effects to those of soy in lowering serum cholesterol levels. In this study we compared the effects of lupin and soy protein on hypertension and vascular functions in spontaneously diabetic Goto-Kakizaki (GK) rat, which develop hypertension when fed a high-salt diet. The rats were fed with a 6% NaCl diet containing either lupin or soy protein isolate (20% weight/weight) for two weeks. In the end of the study the SBP was 18.6 mmHg lower (p<0.001) in the lupin group, and 12.0 mmHg lower (p<0.01) in the soy group than in the control group. Lupin and soy treatments normalised the decreased vasocontraction observed in the NaCl-fed control group, but only lupin treatment improved the impaired endothelium-dependent vasorelaxation. The attenuation of hypertension is likely to be mediated by the corrected vascular dysfunction, whose precise mechanism and the possible clinical relevance remains to be studied further.

p27(SJ), a novel protein in St John's Wort, that suppresses expression of HIV-1 genome

Transcription of the HIV-1 genome is controlled by the cooperation of viral regulatory proteins and several host factors which bind to specific DNA sequences within the viral promoter spanning the long terminal repeat, (LTR). Here, we describe the identification of a novel protein, p27(SJ), present in a laboratory callus culture of Hypericum perforatum (St John's Wort) that suppresses transcription of the HIV-1 genome in several human cell types including primary culture of microglia and astrocytes. p27(SJ) associates with C/EBPbeta, a transcription factor that regulates expression of the HIV-1 genome in macrophages and monocytic cells, and the viral transactivator, Tat. The association of p27(SJ) with C/EBPbeta and Tat alters their subcellular localization, causing their accumulation in the perinuclear cytoplasmic compartment of the cells. Fusion of a nuclear localization signal to p27(SJ) forces its entry into the nucleus and diminishes the capacity of p27(SJ) to suppress Tat activity, but does not alter its ability to suppress C/EBPbeta activation of the LTR. Results from binding assays showed the inhibitory effect of p27(SJ) on C/EBPbeta interaction with DNA. Finally, our results demonstrate that expression of p27(SJ) decreases the level of viral replication in HIV-1-infected cells. These observations suggest the potential for the development of a therapeutic advance based on p27(SJ) protein to control HIV-1 transcription and replication in cells associated with HIV-1 infection in the brain.

Suppression of growth of tumour cell lines in vitro and tumours in vivo by mistletoe lectins

A variety of studies have shown that incubation of different tumour cell lines with mistletoe lectins (MLs) in vitro has a marked cytotoxic effect. In the concentration range of low cytotoxicity cell death induced by ML-I is quantitatively due to apoptotic processes. The first events observed being membrane perforation and protusions. Simultaneous treatment of certain tumour cells with MLs rendered them more sensitive to induction of apoptosis by TNFalpha. The immunomodulatory activity of ML-I was investigated by measuring cytokine release and the results confirmed that cytokine induction by the lectin is regulated at the transcriptional level. ML-I has been shown to potentiate the effect of chemotherapeutic drugs. In addition to an in vitro effect a number of workers have demonstrated that MLs suppress tumour growth in vivo. Mistletoe lectins have been administered to animals locally to the tumour, systemic, subcutaneously or by the oral route via the diet. In many cases apoptosis was observed in the tumour and instances where complete tumour ablation has occurred have been reported. It has been hypothesized that the anticancer efficacy of tumour necrosis factor-alpha (TNFalpha) is potentiated by MLs isolated from both European and Korean mistletoe. There is accumulating evidence that both types of MLs are able to induce an anti-angiogenic response in the host suggesting that the anti-metastatic effect observed on a series of tumour cell lines in mice is in part due to an inhibition of tumour-induced angiogenesis and in part due to an induction of apoptosis.

Protective Effect of a 43 kD Protein from the Leaves of the Herb, Cajanus indicus L on Chloroform Induced Hepatic-disorder

Cajanus indicus is a herb with medicinal properties and is traditionally used to treat various forms of liver disorders. Present study aimed to evaluate the effect of a 43 kD protein isolated from the leaves of this herb against chloroform induced hepatotoxicity. Male albino mice were intraperitoneally treated with 2 mg/kg body weight of the protein for 5 days followed by oral application of chloroform (0.75 ml/kg body weight) for 2 days. Different biochemical parameters related to physiology and pathophysiology of liver, such as, serum glutamate pyruvate transaminase and alkaline phosphatase were determined in the murine sera under various experimental conditions. Direct antioxidant role of the protein was also determined from its reaction with Diphenyl picryl hydroxyl radical, superoxide radical and hydrogen peroxide. To find out the mode of action of this protein against chloroform induced liver damage, levels of antioxidant enzymes catalase, superoxide dismutase and glutathione-S-transferase were measured from liver homogenates. Peroxidation of membrane lipids both in vivo and in vitro were also measured as malonaldialdehyde. Finally, histopathological analyses were done from liver sections of control, toxin treated and protein pre- and post-treated (along with the toxin) mice. Levels of serum glutamate pyruvate transaminase and alkaline phosphatase, which showed an elevation in chloroform induced hepatic damage, were brought down near to the normal levels with the protein pretreatment. On the contrary, the levels of antioxidant enzymes such as catalase, superoxide dismutase and glutathione-S-transferase that had gone down in mice orally fed with chloroform were significantly elevated in protein pretreated ones. Besides, chloroform induced lipid peroxidation was effectively reduced by protein treatment both in vivo and in vitro. In cell free system the protein effectively quenched diphenyl picryl hydroxyl radical and superoxide radical, though it could not catalyse the breakdown of hydrogen peroxide. Post treatment with the protein for 3 days after 2 days of chloroform administration showed similar results. Histopathological studies indicated that chloroform induced extensive tissue damage was less severe in the mice livers treated with the 43 kD protein prior and post to the toxin administration. Results from all these data suggest that the protein possesses both preventive and curative role against chloroform induced hepatotoxicity and probably acts by an anti-oxidative defense mechanism.