N-substituted pyrrole carboxylic acid derivatives from 3,4-dihydroxyketons

Since the chemical industry is largely dependent on petrol-based feedstocks, new sources are required for a sustainable industry. Conversion of biomass to high-value compounds provides an environmentally friendly and sustainable approach, which might be a potential solution to reduce petrol-based starting materials. This also applies for N-heterocycles, which are a common structural motif in natural products, pharmaceuticals and functional polymers. The synthesis of pyrroles is a well-studied and established process. Nevertheless, most routes described are not in line with the principles of green and sustainable chemistry and employ harsh reaction conditions and harmful solvents. In this study, 3,4-dihydroxyketons are used as excellent platform chemicals for the production of N-substituted pyrrole-2-carboxylic- and pyrrole-2,5-dicarboxylic acids, as they can be prepared from glucose through the intermediate d-glucarate and converted into pyrrolic acid derivatives under mild conditions in water. The scope of this so far unknown reaction was examined using a variety of primary amines and aqueous ammonium chloride leading to pyrrolic acid derivatives with N-substituents like alkane-, alkene-, phenyl- and alcohol-groups with yields up to 20 %. The combination of both, enzymatic conversion and chemical reaction opens up new possibilities for further process development. Therefore, a continuous chemo-enzymatic system was set up by first employing an immobilized enzyme to catalyze the conversion of d-glucarate to the 3,4-dihydroxyketone, which is further converted to the pyrrolic acid derivatives by a chemical step in continuous flow.

Development of a Highly Selective NAD+ -Dependent Glyceraldehyde Dehydrogenase and its Application in Minimal Cell-Free Enzyme Cascades

Anthropogenic climate change has been caused by over-exploitation of fossil fuels and CO2 emissions. To counteract this, the chemical industry has shifted its focus to sustainable chemical production and the valorization of renewable resources. However, the biggest challenges in biomanufacturing are technical efficiency and profitability. In our minimal cell-free enzyme cascade generating pyruvate as the central intermediate, the NAD+ -dependent, selective oxidation of D-glyceraldehyde was identified as a key reaction step to improve the overall cascade flux. Successive genome mining identified one candidate enzyme with 24-fold enhanced activity and another whose stability is unaffected in 10 % (v/v) ethanol, the final product of our model cascade. Semi-rational engineering improved the substrate selectivity of the enzyme up to 21-fold, thus minimizing side reactions in the one-pot enzyme cascade. The final biotransformation of D-glucose showed a continuous linear production of ethanol (via pyruvate) to a final titer of 4.9 % (v/v) with a molar product yield of 98.7 %. Due to the central role of pyruvate in diverse biotransformations, the optimized production module has great potential for broad biomanufacturing applications.

Integrating Carbohydrate and C1 Utilization for Chemicals Production

In the face of increasing mobility and energy demand, as well as the mitigation of climate change, the development of sustainable and environmentally friendly alternatives to fossil fuels will be one of the most important tasks facing humankind in the coming years. In order to initiate the transition from a petroleum-based economy to a new, greener future, biofuels and synthetic fuels have great potential as they can be adapted to already common processes. Thereby, especially synthetic fuels from CO₂ and renewable energies are seen as the next big step for a sustainable and ecological life. In our study, we directly address the sustainable production of the most common biofuel, ethanol, and the highly interesting next-generation biofuel, isobutanol, from methanol and xylose, which are directly derivable from CO₂ and lignocellulosic waste streams, respectively, such integrating synthetic fuel and biofuel production. After enzyme and reaction optimization, we succeeded in producing either 3 g L^-1 ethanol or 2 g L^-1 isobutanol from 7.5 g L^-1 xylose and 1.6 g L^-1 methanol. In our cell-free enzyme system, C1-compounds are efficiently combined and fixed by the key enzyme transketolase and converted to the intermediate pyruvate. This opens the way for a hybrid production of biofuels, platform chemicals and fine chemicals from CO₂ and lignocellulosic waste streams as alternative to conventional routes depending solely either on CO₂ or sugars.

Substrate scope of a dehydrogenase from Sphingomonas species A1 and its potential application in the synthesis of rare sugars and sugar derivatives

Rare sugars and sugar derivatives that can be obtained from abundant sugars are of great interest to biochemical and pharmaceutical research. Here, we describe the substrate scope of a short‐chain dehydrogenase/reductase from Sphingomonas species A1 (SpsADH) in the oxidation of aldonates and polyols. The resulting products are rare uronic acids and rare sugars respectively. We provide insight into the substrate recognition of SpsADH using kinetic analyses, which show that the configuration of the hydroxyl groups adjacent to the oxidized carbon is crucial for substrate recognition. Furthermore, the specificity is demonstrated by the oxidation of d‐sorbitol leading to l‐gulose as sole product instead of a mixture of d‐glucose and l‐gulose. Finally, we applied the enzyme to the synthesis of l‐gulose from d‐sorbitol in an in vitro system using a NADH oxidase for cofactor recycling. This study shows the usefulness of exploring the substrate scope of enzymes to find new enzymatic reaction pathways from renewable resources to value‐added compounds.

Thermostabilization of the uronate dehydrogenase from Agrobacterium tumefaciens by semi-rational design

Aldaric acids represent biobased 'top value-added chemicals' that have the potential to substitute petroleum-derived chemicals. Until today they are mostly produced from corresponding aldoses using strong chemical oxidizing agents. An environmentally friendly and more selective process could be achieved by using natural resources such as seaweed or pectin as raw material. These contain large amounts of uronic acids as major constituents such as glucuronic acid and galacturonic acid which can be converted into the corresponding aldaric acids via an enzyme-based oxidation using uronate dehydrogenase (Udh). The Udh from Agrobacterium tumefaciens (UdhAt) features the highest catalytic efficiency of all characterized Udhs using glucuronic acid as substrate (829 s-1 mM-1). Unfortunately, it suffers from poor thermostability. To overcome this limitation, we created more thermostable variants using semi-rational design. The amino acids for substitution were chosen according to the B factor in combination with four additional knowledge-based criteria. The triple variant A41P/H101Y/H236K showed higher kinetic and thermodynamic stability with a T 5015 value of 62.2 °C (3.2 °C improvement) and a ∆∆GU of 2.3 kJ/mol compared to wild type. Interestingly, it was only obtained when including a neutral mutation in the combination.

Can we use gonadotropin plasma concentration as surrogate marker for BMI-related incomplete estrogen suppression in breast cancer patients receiving anastrozole?

BACKGROUND

BMI has been suggested to impact on estrogenic activity in patients receiving anastrozole resulting in a reduced treatment efficacy in obese women. Current evidence in this regard is controversially discussed. Since estradiol is inversely correlated with gonadotropins it can be assumed that an impact of BMI is also reflected by gonadotropin plasma concentrations. We aim at investigating the impact of BMI on the hormonal state of breast cancer (BC) patients receiving anastrozole indicated by LH, FSH and SHBG as well as estradiol.

METHODS

We determined gonadotropin-, estradiol- and anastrozole- serum concentrations from postmenopausal, early stage breast cancer patients receiving upfront anastrozole within routine after care. Gonadotropin plasma concentrations were derived from the routine laboratory examination report. A liquid chromatography tandem mass spectrometry method was used for the measurement of anastrozole serum concentrations. BMI was assessed within the routine after-care check-up.

RESULTS

The overall sample comprised 135 BC patients with a mean age of 65.3 years. BMI was significantly correlated with LH, FSH and SHBG. This association was neither influenced by age nor by anastrozole serum concentrations according to the regression model. Despite aromatase inhibition 12% of patients had detectable estrogen levels in routine quantification.

CONCLUSION

Obese women have an altered hormonal situation compared to normally weight women under the same dose of anastrozole. Our study findings are a further indicator for the relevance of BMI in regard of anastrozole metabolism and possible estrogenic activity indicated by gonadotropin plasma level.

Identification and characterization of two new 5-keto-4-deoxy-D-Glucarate Dehydratases/Decarboxylases

Background

Hexuronic acids such as D-galacturonic acid and D-glucuronic acid can be utilized via different pathways within the metabolism of microorganisms. One representative, the oxidative pathway, generates α-keto-glutarate as the direct link entering towards the citric acid cycle. The penultimate enzyme, keto-deoxy glucarate dehydratase/decarboxylase, catalyses the dehydration and decarboxylation of keto-deoxy glucarate to α-keto-glutarate semialdehyde. This enzymatic reaction can be tracked continuously by applying a pH-shift assay.

Results

Two new keto-deoxy glucarate dehydratases/decarboxylases (EC 4.2.1.41) from Comamonas testosteroni KF-1 and Polaromonas naphthalenivorans CJ2 were identified and expressed in an active form using Escherichia coli ArcticExpress(DE3). Subsequent characterization concerning K_m, k_cat and thermal stability was conducted in comparison with the known keto-deoxy glucarate dehydratase/decarboxylase from Acinetobacter baylyi ADP1. The kinetic constants determined for A. baylyi were K_m 1.0 mM, k_cat 4.5 s⁻¹, for C. testosteroni K_m 1.1 mM, k_cat 3.1 s⁻¹, and for P. naphthalenivorans K_m 1.1 mM, k_cat 1.7 s⁻¹. The two new enzymes had a slightly lower catalytic activity (increased K_m and a decreased k_cat) but showed a higher thermal stability than that of A. baylyi. The developed pH-shift assay, using potassium phosphate and bromothymol blue as the pH indicator, enables a direct measurement. The use of crude extracts did not interfere with the assay and was tested for wild-type landscapes for all three enzymes.

Conclusions

By establishing a pH-shift assay, an easy measurement method for keto-deoxy glucarate dehydratase/decarboxylase could be developed. It can be used for measurements of the purified enzymes or using crude extracts. Therefore, it is especially suitable as the method of choice within an engineering approach for further optimization of these enzymes.

Electronic supplementary material

The online version of this article (doi:10.1186/s12896-016-0308-3) contains supplementary material, which is available to authorized users.

Abstract P1-11-02: Psychological morbidity in breast cancer survivors: Prevalence rates and determinants

Background: The number of breast cancer survivors (BCS) is steadily increasing due to improved treatment options, early detection and younger age at diagnosis. Thus, it is increasingly important to determine and better understand the psychological outcome following a cancer diagnosis and treatment in long-term. This might contribute to meeting the long-term health care demands of cancer survivors. We aimed at investigating levels and determinants of anxiety and depression (AD) in BCS.

Patients and Methods: We included BCS with a non-metastatic disease in the stage of after-care. AD was determined as part of a cross-sectional, comprehensive patient reported outcome (PRO) assessment (incl. Functional Assessment of Cancer Therapy-G/+B/+ES, Eating Disorder Examination-Questionnaire, Sexual Activity Questionnaire and Body Image Scale) using the Hospital Anxiety and Depression Scale (HADS). Prevalence rates of AD and sample characteristics are presented descriptively using percentages, means and standard deviations. Predictors of anxiety and depression are identified by means of regression analysis.

Results: A final sample of 743 breast cancer survivors who were on average 2.9 years post diagnosis (range: 0.1-11.3 years) participated in the study. Mean patient age was 56.4a (SD 11.5a), 2/3 of patients were postmenopausal. 22.5% of patients reported clinically relevant levels of anxiety and 11.2% of depression. Older age (β=0.012, t=2.53, p<0.05), higher endocrine symptoms (β=-0.037, t=-8.89, p<0.01) and reduced functional well-being (β=-0.034, t=-7.73, p<0.01) were predictive for anxiety and depression in the regression model. The model explained 39.3% of the variance of anxiety and depression.

Conclusion: A distinct proportion of BCS report clinically relevant, long-term psychological morbidity. Especially older BCS, experiencing higher levels of endocrine symptoms and reduced functional well-being, seem to be at risk for psychological morbidity. A routine PRO-screening for psychological morbidity including the assessment of associated risk factors in this patient population might contribute to the identification of those women in need for psychological/ psychiatric treatment and in conjunction, improve cancer care.

Citation Format: Hubalek M, Sztankay M, Oberguggenberger A, Meraner V, Egle D, Mangweth-Matzek B, Beer B, Huber N, Sperner-Unterweger B. Psychological morbidity in breast cancer survivors: Prevalence rates and determinants. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P1-11-02.

Levels in neurotransmitter precursor amino acids correlate with mental health in patients with breast cancer

Breast cancer is the most common cancer among females. Approximately 30% of cancer patients develop depression or depressive adaptation disorder within 5 years post diagnosis. Low grade inflammation and subsequent changes in neurotransmitter levels could be the pathophysiological link. In the current study we investigated the association of neurotransmitter precursor amino acids with a diagnosis of depression or state anxiety in 154 subjects suffering from breast cancer (BCA(+)), depression (DPR(+)), both or neither. Sociodemographic parameters, severity of depressive symptoms, and state anxiety (ANX) were recorded. Neopterin, kynurenine/tryptophan and phenylalanine/tyrosine were analysed by HPLC or ELISA. Significantly higher serum neopterin values were found in DPR(+) patients (p = 0.034) and in ANX(+) subjects (p = 0.008), as a marker of Th1-related inflammation. The phenylalanine/tyrosine ratio (index of the catecholamine pathway) was associated with the factors "breast cancer" and "depression" and their interaction (all p < 0.001); it was highest in the DPR(+)BCA(+) group. The kynurenine/tryptophan ratio (index of the serotonin pathway) was significantly associated with the factors "breast cancer" and "state anxiety" and their interaction (p < 0.001, p = 0.026, p = 0.02, respectively); it was highest in the ANX(+)BCA(+) group. In BCA(+) patients kynurenine/tryptophan ratios correlated with severity of state anxiety (r = 0.226, p = 0.048, uncorrected) and phenylalanine/tyrosine ratios with severity of depressive symptoms (r = 0.376, p < 0.05, corrected). In conclusion, levels of neurotransmitter precursor amino acids correlate with mental health, an effect which was much more pronounced in BCA(+) patients than in BCA(-) subjects. Aside from identifying underlying pathophysiological mechanisms, these results could be the basis for future treatment studies: in BCA(+) patients with depression the use of serotonin-noradrenaline reuptake inhibitors might be recommended while in those with predominant anxiety selective serotonin reuptake inhibitors might be the treatment of choice.

A water-forming NADH oxidase from Lactobacillus pentosus suitable for the regeneration of synthetic biomimetic cofactors

The cell-free biocatalytic production of fine chemicals by oxidoreductases has continuously grown over the past years. Since especially dehydrogenases depend on the stoichiometric use of nicotinamide pyridine cofactors, an integrated efficient recycling system is crucial to allow process operation under economic conditions. Lately, the variety of cofactors for biocatalysis was broadened by the utilization of totally synthetic and cheap biomimetics. Though, to date the regeneration has been limited to chemical or electrochemical methods. Here, we report an enzymatic recycling by the flavoprotein NADH-oxidase from Lactobacillus pentosus (LpNox). Since this enzyme has not been described before, we first characterized it in regard to its optimal reaction parameters. We found that the heterologously overexpressed enzyme only contained 13% FAD. In vitro loading of the enzyme with FAD, resulted in a higher specific activity towards its natural cofactor NADH as well as different nicotinamide derived biomimetics. Apart from the enzymatic recycling, which gives water as a by-product by transferring four electrons onto oxygen, unbound FAD can also catalyze the oxidation of biomimetic cofactors. Here a two electron process takes place yielding H2O2 instead. The enzymatic and chemical recycling was compared in regard to reaction kinetics for the natural and biomimetic cofactors. With LpNox and FAD, two recycling strategies for biomimetic cofactors are described with either water or hydrogen peroxide as by-product.

A comprehensive analysis of the geranylgeranylglyceryl phosphate synthase enzyme family identifies novel members and reveals mechanisms of substrate specificity and quaternary structure organization

Geranylgeranylglyceryl phosphate synthase (GGGPS) family enzymes catalyse the formation of an ether bond between glycerol-1-phosphate and polyprenyl diphosphates. They are essential for the biosynthesis of archaeal membrane lipids, but also occur in bacterial species, albeit with unknown physiological function. It has been known that there exist two phylogenetic groups (I and II) of GGGPS family enzymes, but a comprehensive study has been missing. We therefore visualized the variability within the family by applying a sequence similarity network, and biochemically characterized 17 representative GGGPS family enzymes regarding their catalytic activities and substrate specificities. Moreover, we present the first crystal structures of group II archaeal and bacterial enzymes. Our analysis revealed that the previously uncharacterized bacterial enzymes from group II have GGGPS activity like the archaeal enzymes and differ from the bacterial group I enzymes that are heptaprenylglyceryl phosphate synthases. The length of the isoprenoid substrate is determined in group II GGGPS enzymes by 'limiter residues' that are different from those in group I enzymes, as shown by site-directed mutagenesis. Most of the group II enzymes form hexamers. We could disrupt these hexamers to stable and catalytically active dimers by mutating a single amino acid that acts as an 'aromatic anchor'.

Abstract P4-02-04: Impact of CYP2D6 Genotype and Side-Effects on Adherence Rates to Tamoxifen in Premenopausal Breast Cancer Patients

Background: Only few studies have investigated the issue of breast cancer patients’ adherence to tamoxifen therapy and factors influencing adherence behavior. Especially in the context of different CYP2D6 genotypes adherence to tamoxifen has not been extensively studied yet. Variations in the CYP2D6 genotype, as well as patients taking inhibitors of CYP2D6 (e.g. antidepressants) contribute to different side effects and adherence rates to adjuvant tamoxifen.

Materials and Methods: 106 premenopausal breast cancer patients who met inclusion criteria were consecutively included in the study at the outpatient unit of the Department of Gynecology, Innsbruck Medical University. Within their routine after care appointment patients completed a comprehensive PRO assessment including the FACT-B/ES, the HADS and a self-report questionnaire on adherence behavior (SMAQ). The multi-method approach comprised the Simplified Medication Adherence Questionnaire, a semi-structured interview, physicians’ ratings and blood levels for tamoxifen metabolites. Additionally, the CYP2D6 genotype was determined in all patients participating in this part of the study.

Results: 19% patients were poor metabolizer (PM), 51% intermediate metabolizer (IM), 29% extensive metabolizer (EM) and 7% ultra-rapid metabolizer (UM). Significant group differences with regard to tamoxifen and endoxifen serum concentrations were found between the metabolization groups (p=0.044). UMs had the lowest tamoxifen and highest endoxifen concentrations. Only 3.2% of the patients analyzed had no measurable tamoxifen concentrations in their serum. All non-compilant patients were from the extensive metabolizer group. However, during follow-up 25% (2/6) of patients with UM genotype, 13% (4/30) with EM genotype, 1% (1/50) with IM genotype and 0% (0/19) with the PM genotype discontinued their tamoxifen therapy due to therapy related side effects. In addition anti-depressants were more frequently prescribed in the extensive metabolizer group leading to lower levels of the active metabolite endoxifen. Conclusion: A trend towards higher hot flashes was observed in the EM and UM group. We did not find significant differences in QOL between

CYP2D6 metabolizing groups. Trend level significance was found for global QOL (on a descriptive level) physical well-being and emotional well-being. Non-adherence to tamoxifen therapy is more frequent in patients with CYP2D6 EM and UM genotype. These preliminary data may explain part of the current controversy over CYP2D6 genotype predicting response to tamoxifen and suggest that patients most likely to benefit from tamoxifen are paradoxically most likely to stop their tamoxifen therapy prematurely.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P4-02-04.

Abstract P5-11-09: A Validated Analytical Method for Monitoring the Plasma Levels of Tamoxifen, Anastrozole and Letrozole in Patients Undergoing Endocrine Therapy

Background: Clinical data have repeatedly shown that tamoxifen as well as anastrazole and letrozole significantly increase the overall survival among breast cancer patients. However, in several cases the use of these drugs is limited by side effects, whose appearance are described to impair the adherence of a patient to endocrine treatment. Frequently, adherence is rated based on patient self-reports. One competent approach to obtain impartial information about patient adherence and its clinical relevance is based on the determination of plasma drug concentrations. The individual steady state plasma level represents an objective measure that may serve as an important comparator to check the patient-reported adherence status in clinical studies. In addition, it may also reveal useful information for the treating physician regarding concentration dependent side effects or therapeutic failure. We have developed and validated a liquid chromatography-tandem mass spectrometry (LC/MS/MS) method for the simultaneous analysis of tamoxifen, anastrazole and letrozole in human plasma. The method was applied in the PRO-BETh study to monitor 320 breast cancer patients undergoing endocrine therapy.

Material and methods: Blood plasma samples were collected from 320 patients undergoing endocrine breast cancer therapy and stored at -20° C. To prepare a sample for LC/MS/MS analysis, 1 ml plasma was treated with a solid phase extraction procedure using a cation mixed-mode polymeric sorbent phase (Strata-X-C cartridges, Phenomenex, CA). Chromatographic separation was accomplished on a reversed-phase column (200 mm x 0.5 mm, Eurosphere-C18, 5 μm, Knauer, Berlin) by using a gradient of acetone in an aqueous hexafluorobutyric acid solution. Mass spectrometric detection was performed on a quadrupole-quadrupole-linear ion trap instrument (Q Trap 3200, Applied Biosystems, Foster City, CA). Results: We have developed a fully validated method for the simultaneous quantitative analysis of tamoxifen, anastrozole and letrozole in human plasma. Validation was accomplished for a concentration range of 25-500 ng/ml for tamoxifen, 10-200 ng/ml for endoxifen, 5-200 ng/ml for anastrozol and 10-300 ng/ml for letrozole. The applicability of the method was demonstrated in the context of the PRO-BETh study, by analyzing plasma samples of 320 patients undergoing endocrine breast cancer therapy. The observed plasma levels showed a high inter-patient variability with measured values between 26-307 ng/ml (mean 125 ng/ml) regarding tamoxifen, 17-301 ng/ml (mean 107 ng/ml) regarding letrozole and 6-102 ng/ml (mean 37 ng/ml) regarding anastrozole. Eight samples did not contain a quantifiable amount of drug, indicating longer abstinence of the corresponding patients regarding endocrine therapy. Conclusions: The developed method represents a reliable and convenient tool for the quantitative analysis of tamoxifen, anastrozol and letrozole in human plasma. The method is dedicated to drug monitoring which is an important part of adherence rating. As exemplified in the context of the PRO-BETh study, the measured steady state plasma levels represent objective measures that serve as important comparators to check the patient-reported adherence status.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P5-11-09.

Abstract P5-11-10: Gonadotropins Plasma Levels Are Significantly Influenced by Body Mass Index in Postmenopausal Breast Cancer Patients Undergoing Endocrine Therapy with Aromatase Inhibitors: Is This a Surrogate Marker for Serum Estrogen Bioactivity?

Background: Estrogens play a crucial role in breast carcinogenesis and progression. The third-generation aromatase inhibitors (AIs) have therefore become the first choice endocrine drugs for post-menopausal women with breast cancer, since they present greater efficacy when compared with tamoxifen. However, mode of action, side effects and tolerability are distinct compared to tamoxifen. In this study, we evaluated clinical side-effects, levels of gonadotropin, prolactin, progesterone and estradiol in postmenopausal women undergoing endocrine treatment with aromatase inhibitors.

Materials and Methods: 128 postmenopausal patients undergoing endocrine therapy with aromatase inhibitors were included in the study. They completed the assessment at their regular 3-month check up. For the assessment of side-effects and symptom burden we used the FACT-B/+ES and the HADS. Blood samples were collected within the routine blood collection and measurement of follicle stimulation hormone (FSH), luteinizing hormone (LH), progesterone, estradiol and prolactin plasma levels were performed by Immunoassay. Data were analyzed using Spearman rank correlation.

Results: We found a significant negative correlation of LH and FSH with body mass index (BMI) of postmenopausal breast cancer patients (LH r=- 0.281, p=0.014; FSH r=-0.250, p=0.029) receiving aromatase inhibitors. Analyses revealed a significant positive correlation for LH and FSH levels with subjectively experienced weight gain (LH r=0.499, p=0.008; FSH r=0.550, p=0.003), dyspareunia and vaginal dryness. Moreover, patients with a BMI ≥25 had significantly more gynaecological symptoms (dyspareunia p=0.008 and vaginal dryness p=0.026) than patients witha lower BMI. Progesterone was significantly associated with subjective weight gain (r=0.248, p=0.014). Prolactin significantly correlated with loss of sex drive (r=0.256, p=0.050), mood swings (r=0.239, p=0.050) and irritability (r=0.244, p=0.046).

Conclusion: Our results reveal distinct endocrine changes among postmenopausal breast cancer patients undergoing endocrine treatment with AIs. These results confirm the central role of estrogens in the evolution of adverse events to aromatase inhibitors. The main observation in this study, however, was the correlation of BMI and levels of hormone influenced by estrogenic activity. LH and FSH which are under control of various estrogen metabolites, were significantly associated with the BMI and might therefore serve as surrogate marker of estrogenic activity in serum of breast cancer patients. Direct measurement of estradiol (E2) showed no correlation with BMI indicating the influence of various other estrogen metabolites on the secretion of gonadotropins. Analysis of serum estrogen receptor bioactivity in these patients is currently underway.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P5-11-10.

Abstract P4-02-17: Polymerase Chain Reaction-Liquid Chromatography-Mass Spectrometry — A Convenient and Cost-Effective Strategy for CYP2D6 Genotyping

Background: Genetic polymorphisms in the drug metabolizing enzyme Cyotchrome P450 2D6 (CYP2D6) gene can significantly influence a person's ability to mediate CYP2D6 dependent metabolism. For example, a notable influence of the CYP2D6 genotype has been described regarding the conversion of tamoxifen to its pharmacologically active metabolites. Thus, the genetic determination of the CYP2D6 metabolizer status has the potential to represent a valuable therapeutic supplement in breast cancer therapy. However, the clinical relevance of the CYP2D6 genotype regarding the treatment of breast cancer with tamoxifen still remains to be elucidated. Due to the high number of relevant polymorphisms to be screened, pharmacogenetic CYP2D6 testing is considered to be time-consuming and laborious and is therefore limited to a few clinical studies only. To enable a more widespread use, we present polymerase chain reaction (PCR) - ion-pair reversed-phase high-performance liquid chromatography — electrospray ionization time of flight mass spectrometry (ICEMS) as fast, convenient and cost-effective strategy for CYP2D6 genotyping.

Material and Methods: After DNA extraction from saliva swabs, the CYP2D6 gene was amplified by a long range PCR. Subsequently, polymorphism-specific short amplicons were generated in a multiplexed PCR. The amplicons were directly analysed by ICEMS. The information necessary to determine the allelic state of a PCR-amplified polymorphic locus were obtained from the measured molecular masses. Gene duplications or deletions were analysed by a long range PCR protocol and subsequent agarose gel detection.

Results: The developed CYP2D6 genotyping approach enables the reliable determination of the most frequent CYP2D6 alleles in Europe (*1, *2, *3, *4, *6, *7, *8, *9, *10, *11, *12, *17, *41) including whole gene duplications and deletions (*5). The assay involves the following steps: (1) collecting biological material in form of non-invasive saliva swabs; (2) DNA extraction; (3) long range PCR for a specific CYP2D6 amplification; (3) multiplexed PCR for the generation of polymorphism-specific short amplicons; (4) direct analysis of the reaction mixture with ICEMS; (4) determination of the allelic state with the measured molecular masses; (5) analysis of gene duplications or deletions by a long range PCR protocol and subsequent agarose gel detection. Genotyping of a single sample costs about 5-10 USD and can be accomplished within 2-3 days. Parallelization increases the sample throughput and reduces costs. For proof of principle, we have applied the developed method in the context of the PRO-BETh study to determine the CYP2D6 status of 106 breast cancer patients treated with tamoxifen. According to the classification of Gaedik A. et al [1], 19% of the typed breast cancer patients turned out to be “Poor Metabolizers", 51% were “Intermediate Metabolizers", 29% were “Extensive Metabolizers” and 7% turned out to be “Ultrarapid Metabolizers”.

Conclusion: PCR-ICEMS represents a cost-effective and convenient tool for pharmacogenetic testing, which enables the determination of the CYP2D6 status using DNA obtained from a non-invasive saliva swab as template.

[1] Gaedigk A. et al, J. Clin Pharmacol Ther. 2007 Jun;81(6):817-20.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P4-02-17.

Abstract P5-11-04: Phenotype-Genotype Correlations in Breast Cancer Patients Treated with Tamoxifen

Background: Personalized medicine strategies are especially relevant for drugs which show a high inter-individual variability regarding their pharmacokinetic and -dynamic properties. Considerable inter-patient variations have been described regarding the plasma concentrations of tamoxifen and its metabolites. Due to the observation that tamoxifen metabolites can show a high pharmacological activity, tamoxifen metabolism has received considerable attention. The metabolism of tamoxifen is complex resulting in a huge number of different products. Important metabolic transformation reactions include demethylation catalyzed by Cytochrome P450 3A4 and hydroxylation mainly catalyzed by Cytochrome P450 2D6 (CYP2D6). The impact of the CYP2D6 activity, which can be predicted from genetic information, on plasma levels and the related pharmacological effects has controversially been discussed. To get a better understanding of the inter-individual differences of the plasma levels of tamoxifen and some of its metabolites we have used liquid chromatography-tandem mass spectrometry (LC/MS/MS) to screen the plasma samples of 106 breast cancer patients. This method enabled the quantification of tamoxifen as well as a relative quantification of demethyltamoxifen and hydroxylated tamoxifen metabolites. To study the impact of enzyme activity on plasma levels, CYP2D6 genotypes were determined as well.

Material and methods: For metabolic profiling 1 ml plasma was treated with a solid phase extraction procedure. Chromatographic separation was accomplished on a reversed-phase column. Analytes were detected by mass spectrometry. For genotyping, the CYP2D6 gene was amplified by a long range PCR followed by a multiplexed PCR to generate specific short amplicons. The amplicons were directly analysed by LC/MS. The information necessary to determine the allelic state were obtained from the measured molecular masses.

Results: We determined the CYP2D6 genotype of 106 breast cancer patients treated with tamoxifen. We found 19% “Poor Metabolizers", 51% “Intermediate Metabolizers", 29% “Extensive Metabolizers” and 7% “Ultrarapid Metabolizers”. The observed plasma concentrations of tamoxifen and its metabolites showed a high inter-patient variability For instance, plasma concentrations between 26-307 ng/ml (mean 125 ng/ml) were observed for tamoxifen. We did not find a significant impact of the CYP2D6 status on tamoxifen plasma levels. However, the demethyltamoxifen/tamoxifen as well as the hydroxytamoxifen/tamoxifen ratios appear to be influenced by the CYP2D6 status: the higher the metabolic activity, the higher the hydroxytamoxifen content and the lower the demethyltamoxifen content.

Conclusions: We have developed analytical tools, which allow the determination of the content of tamoxifen and its major metabolites in human plasma and the genotyping of the CYP2D6 gene. Phenotypic and genotypic data of 106 patients were acquired. Correlation of the data revealed that the genotype had no significant impact on tamoxifen plasma levels. Nevertheless, patients with a predicted higher CYP2D6 activity showed lower demethyltamoxifen/tamoxifen ratios as well as higher hydroxytamoxifen/tamoxifen ratios.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P5-11-04.

Abstract PD08-02: The Impact of Patient Reported Outcomes (PRO) on the Evaluation of Therapy Related Side-Effects and the Improvement of Adherence to Endocrine Treatment in Breast Cancer Patients

Background: Long term treatment regimen with significant side effects may diminish a patient's quality of life (QOL) and consequently undermine adherence. Endocrine treatment for breast cancer causes various side effects, which can lead to early discontinuation of this effective therapy. Current knowledge on patients’ quality of life (QOL) impairments caused by endocrine therapy originates from clinicians’ impressions and expert ratings. This runs the risk of underestimating the effects of endocrine therapy on patients’ quality of life. Patient reported outcome (PRO) may provide higher accuracy and may therefore essentially contribute to medication evaluation and clinical decision making. In this study, we report on the patient reported outcome (PRO) related to endocrine therapy in early breast cancer.

Methods: Pre-and postmenopausal breast cancer outpatients treated with aromatase inhibitors (AIS) or tamoxifen were approached at their routine control appointment with the treating physician. We conducted a comprehensive PRO assessment comprising the following scales: FACT-B/+ES and HADS (high scores indicate high symptoms). In a short, semi-structured interview data on patients’ general medication intake behavior were collected focusing on the intake of complementary and alternative medicine (CAM)

Results: We analyzed PRO data of 240 patients undergoing endocrine treatment. 66.6% received AI therapy, 71.9% were postmenopausal. We found high levels of symptom burden in this study group: 55.9% had moderate to severe bone pain, 47.8% menopausal symptoms and 49.1% loss of sex drive. Postmenopausal women in the AI group had significantly more symptoms on the endocrine subscale (mean 24.25 vs. 16.42, p=0.045), significantly more anxiety (mean 8.8 vs. 5.11, p=0.036) and depression (mean 8.75 vs. 3.86, p=0.011). In the tamoxifen group premenopausal patients scored significantly higher on all scales. Moreover, patients who used complementary substances had a significant lower physical well-being (22.70 vs. 24.39, p=0.007) and more endocrine symptoms (22.63 vs. 16.30, p=0.004).

Conclusion:The results of our study show a significantly higher assessment of physical side-effects and psychosocial burden on part of the patients than implied by clinicians’ reports and expert ratings. PRO data may therefore provide a more accurate measure for symptom burden and contribute to individualized clinical decision making. It is an important tool to detect and effectively treat therapy related side effect to ultimately preserve adherence to endocrine treatment. According to our findings, it appears mandatory to incorporate PRO data in individualized clinical decision making to arrive at a more accurate assessment of symptom burden.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr PD08-02.

Selective anxiolysis produced by ocinaplon, a GABA(A) receptor modulator

Benzodiazepines remain widely used for the treatment of anxiety disorders despite prominent, often limiting side effects including sedation, muscle relaxation, and ataxia. A compound producing a robust anxiolytic action comparable to benzodiazepines, but lacking these limiting side effects at therapeutic doses (an anxioselective agent), would represent an important advance in the treatment of generalized anxiety disorder, and perhaps other anxiety disorders. Here we report that the pyrazolo[1,5-a]-pyrimidine, ocinaplon, exhibits an anxioselective profile in both preclinical procedures and in patients with generalized anxiety disorder, the most common of the anxiety disorders. In rats, ocinaplon produces significant muscle relaxation, ataxia, and sedation only at doses >25-fold higher than the minimum effective dose (3.1 mg/kg) in the Vogel "conflict" test. This anticonflict effect is blocked by flumazenil (Ro 15-1788), indicating that like benzodiazepines, ocinaplon produces an anxiolytic action through allosteric modulation of GABA(A) receptors. Nonetheless, in eight recombinant GABA(A) receptor isoforms expressed in Xenopus oocytes, the potency and efficacy of ocinaplon to potentiate GABA responses varied with subunit composition not only in an absolute sense, but also relative to the prototypical benzodiazepine, diazepam. In a double blind, placebo controlled clinical trial, a 2-week regimen of ocinaplon (total daily dose of 180-240 mg) produced statistically significant reductions in the Hamilton rating scale for anxiety scores. In this study, the incidence of benzodiazepine-like side effects (e.g., sedation, dizziness) in ocinaplon-treated patients did not differ from placebo. These findings indicate that ocinaplon represents a unique approach both for the treatment and understanding of anxiety disorders.

Fabrication of highly porous scaffold materials based on functionalized oligolactides and preliminary results on their use in bone tissue engineering

Tissue engineering offers a promising new approach to repair bone defects. Its practical realisation is connected with the development of suitable scaffold materials. In the present work, functionalized oligolactides have been prepared and used as macromers for the scaffold fabrication The developed fabrication process leads to highly porous scaffolds, available in various shapes and sizes, with an open inter-connective pore structure and porosities up to 90%. Degradable or even osteoconductive components as well as biocompatible co-monomers can be used as additives to modulate the scaffold properties. Under in vitro conditions, the scaffolds exhibit a continuous degradation with varying degradation rates depending on their material composition. In vitro studies on the cultivation of osteoblasts on the scaffolds were performed and revealed their excellent biocompatibility. Cell growth on the scaffold surfaces and inside the scaffolds, formation of extracellular matrix and starting mineralization were detected by microscopical and histological analyses. Based on these results the developed materials are well-suited candidates for the design of tailor-made matrices in bone tissue engineering

Analysis of SIV-specific CTL in the rhesus macaque model of AIDS: the use of simian fibroblasts as an alternative source of target cells for chromium release assays

The simian immunodeficiency virus (SIV) model of AIDS is widely used for the development of human immunodeficiency virus (HIV) vaccine strategies, particularly for the analysis of correlates of protective immunity. As it is not always possible to establish autologous B-lymphoblastoid cell lines (B-LCL) for use as targets in the analysis of cytotoxic T cell (CTL) activity, we have compared B-LCL with primary simian skin cells. Using a well-defined SIV gag-encoded CTL epitope restricted by Mamu A*01 major histocompatibility complex (MHC) class I, we have shown that peripheral blood mononuclear cells (PBMC) from vaccinated and infected macaques can kill MHC class I-matched skin fibroblasts presenting the cognate epitope but that skin fibroblasts are a less sensitive target than B-LCL for the detection of CTL.

Chemoattractant factors and the control of human immunodeficiency virus replication

Factors secreted by CD8(+) T cells have been described to suppress immunodeficiency virus replication. The research efforts to identify these factors led to the proposal of some candidate proteins as being responsible for the antiviral effects. Chemokines and IL-16 are secreted by CD8(+) T cells and inhibit HIV replication through different mechanisms. However, their antiviral properties cannot fully explain the inhibitory activities found in cell culture supernatants from CD8(+) T cells.

Treatment of feline leukemia virus (FeLV) infection

FeLV infection is still considered to account for most disease-related deaths in pet cats. Different treatment attempts with various drugs were performed in the past but none resulted in healing or complete virus elimination. Therefore, it caused a sensation when Horber and Mayr [Horber, D., Mayr, B., 1991. Prax. 19, 311-314; Horber, D., Schnabl, W., Mayr, B., 1992. Tierarztl. Umschau 47, 556-560; Mayr, B., Horber, D., 1992. Kleintierprax. 37, 515-518] published that they were able to cure 80 to 100% FeLV-infected cats from viremia by using an immunomodulating compound. Articles in cat breeder and cat owner journals appeared assuming that obviously there is a rescue for FeLV-infected cats suffering from this deadly infection. The immunomodulator [Buttner, M., 1993. Comp. Immun. Microbiol. Infect. Dis. 18, 1-10] used in those studies was the so-called 'paramunity inducer' PIND-ORF (Baypamun, Bayer, Leverkusen, Germany) consisting of inactivated parapox ovis virus. Since that time, Baypamun is the most commonly used drug for treatment of FeLV infection in Germany and other European countries. Four placebo-controlled double-blind trials were performed to determine the therapeutic efficacy of Baypamun and other compounds in naturally FeLV-infected cats under controlled conditions.

Why are the natural hosts of SIV resistant to AIDS?

An increasing number of African primate species have been shown to be infected in the wild with their own distinct variants of simian immunodeficiency virus. The most striking feature of these natural host systems is the lack of AIDS-like disease despite long-term infection. In the African green monkey (AGM)/SIVagm system there is no evidence that a vigorous antiviral immune response, a lack of variability or a low virus load accounts for this lack of pathogenicity. New-born AGMs appear to be even more resistant to the virus than adults, despite their immature immune system and higher pool of target cells. The fact that AGMs, unlike HIV-infected humans, lack a humoral immune response to non-denatured Gag protein and do not show trapping of virus in the lymph nodes suggested that tolerance to Gag might prevent the formation of immune complexes which would normally be filtered out by the lymphoid tissues with detrimental results. This apparent tolerance to Gag is a common feature of many, if not all, of the natural host systems and might explain why the lymph nodes and immune system in general remain intact in these primates in the face of continuous, high level virus replication.

Characteristics of Filoviridae: Marburg and Ebola viruses

Filoviruses are enveloped, nonsegmented negative-stranded RNA viruses. The two species, Marburg and Ebola virus, are serologically, biochemically, and genetically distinct. Marburg virus was first isolated during an outbreak in Europe in 1967, and Ebola virus emerged in 1976 as the causative agent of two simultaneous outbreaks in southern Sudan and northern Zaire. Although the main route of infection is known to be person-to-person transmission by intimate contact, the natural reservoir for filoviruses still remains a mystery.

SIVmac vaccine studies using whole inactivated virus antigen sequentially depleted of viral proteins

Groups of four rhesus monkeys were immunised at 0, 1, 2, and 13 months with whole inactivated SIVmac32H, SIVmac depleted of the outer envelope glycoprotein gp130, virus cores depleted of the lipid membrane (and hence transmembrane glycoproteins), or purified gag protein. These macaques plus controls were challenged with either the homologous SIVmac251-32H grown in human cells or the same virus passed once through monkey cells. None of those challenged with monkey-grown virus were protected, whereas all in the whole and gp130-depleted virus groups, and one in the core group resisted challenge with human-grown virus. As the only difference between the challenge viruses was a single in vitro passage in monkey cells it can be concluded that protection was solely due to human cell components. Finally, passive transfer of high titer IgG from monkeys infected with the homologous challenge virus failed to protect monkeys from infection despite the presence of circulating neutralising antibodies.

Simian immunodeficiency virus of African green monkeys is apathogenic in the newborn natural host

Several studies have demonstrated that newborn animals are more susceptible to disease development following infection with retroviruses than adults. Adult African green monkeys (AGMs) infected with SIVagm do not develop AIDS-like disease and the objective of the study was to determine whether experimental infection of newborn AGMs with SIVagm would result in pathogenesis. Neonatal AGMs were found to have a higher percentage of circulating CD4+ lymphocytes than adults (62% versus 14%) and therefore a higher potential pool of target cells for SIVagm infection. However, no differences in the in vitro replication kinetics of SIVagm in peripheral blood mononuclear cells of adult or neonatal AGMs could be observed. In vivo, the neonatal AGMs became viremic at the earliest two months after inoculation whereas the adult AGMs had evidence of virus replication already 2 to 6 weeks after infection. None of the animals developed AIDS-like symptoms upon infection. In the heterologous cynomolgus macaque host, a newborn infected with SIVagm developed early high virus loads and died two months after birth with AIDS-like histopathologic features. It would therefore appear that in contrast to the situation with many other retroviruses, newborn AGMs are no more permissive to SIVagm infection than are adults.

The U3 promoter and the nef gene of simian immunodeficiency virus (SIV) smmPBj1.9 do not confer acute pathogenicity upon SIVagm

Two chimeric proviruses comprising the U3 promoter and the nef gene of simian immunodeficiency virus (SIV) smmPBj1.9 in addition to other genomic regions of SIVagm3mc from African green monkeys (Cercopithecus aethiops) were constructed. The derived chimeric viruses (SIVagm3mc/SIVsmmPBj1.9) were both able to replicate in nonstimulated peripheral blood leukocytes from pig-tailed macaques (Macaca nemestrina), a biological property often correlated with acute pathogenicity. However, only one of the chimeric viruses was acutely pathogenic, inducing a rapid depletion of the peripheral CD4+ T cells in two infected pig-tailed macaques within 10 days after infection in a manner similar to infection with SIVsmmPBj1.9 itself. The other chimeric virus actively replicated during the first 8 weeks after experimental infection of two pig-tailed macaques but induced neither acute disease nor CD4+ T-cell depletion for 113 weeks after infection. Thus, the U3 promoter and the nef gene of SIVsmmPBj1.9 alone appear to be insufficient to confer acute pathogenicity to SIVagm3mc.

Vaccine effect using a live attenuated nef-deficient simian immunodeficiency virus of African green monkeys in the absence of detectable vaccine virus replication in vivo

Immunization of adult macaques with live attenuated simian immunodeficiency viruses (SIVs) lacking the nef genes has been shown to protect against challenge with full-length pathogenic SIV. To test live attenuated virus vaccines for the first time in a natural host we have constructed a mutant SIV from African green monkeys (SIVagm) with a deletion of 125 bp in the nef gene (SIVagm3 delta nef). This mutant showed moderately delayed in vitro replication in the T cell line MOLT-4/8 and in primary peripheral blood mononuclear cells from African green monkeys (Cercopithecus aetiops) and pig-tailed macaques (Macaca nemestrina) compared with cloned wild-type SIVagm3. In contrast, in vivo replication of SIVagm3 delta nef in African green monkeys was severely impaired or undetectable and did not induce seroconversion. After challenge with wild-type SIVagm3 the SIVagm3 delta nef preinoculated African green monkeys showed a memory antibody response that declined after week 2. In three of four African green monkeys the cell-associated virus load and in two of four African green monkeys the plasma virus load was dramatically decreased after the challenge compared with naive control animals. The remaining animal showed no evidence of productive challenge virus replication. This study demonstrates that a strong vaccine effect or protection in the SIVagm/African green monkey system is possible using a live attenuated vaccine in the absence of a productive infection and corresponding humoral immune response.

Comparison of T-cell subpopulations in cats naturally infected with feline leukaemia virus or feline immunodeficiency virus

T-cell subsets were studied by flow cytometry in 58 feline leukaemia virus (FeLV)-positive cats with naturally acquired FeLV infection to determine whether the changes in CD4+ or CD8+ T cell populations differed from those observed in 55 feline immunodeficiency virus (FIV)-positive cats with naturally acquired FIV infection. The sole criterion for inclusion into the study was seropositivity. Mean (SD) CD4+ T cell values of FeLV positive cats were decreased to 31.1 (8.0) per cent and their CD8+ T cell values were increased to 22.8 (6.3) per cent in comparison with uninfected control cats (37.9 [9.5] per cent CD4+; 15.2 [6.3] per cent CD8+). The CD4+/CD8+ ratio was reduced to 1.5 (0.7), compared with 3.0 (1.5) in 39 FeLV-and FIV-negative control cats. Differences from control values were significant, but there was no significant difference between CD4+ and CD8+ lymphocytes of FeLV-versus FIV-infected cats. These findings indicate that FeLV and FIV have similar effects on T lymphocyte subsets. Both retrovirus infections can induce immunodeficiency, both viruses infect a broad range of lymphohaemopoietic cells, despite having different primary target cells, and can induce the killing of lymphocytic cells in vitro. It is concluded that a decreased CD4+/CD8+ ratio is not restricted to FIV infections but may also occur in FeLV infection.

Lack of dichotomy between virus load of peripheral blood and lymph nodes during long-term simian immunodeficiency virus infection of African green monkeys

During the asymptomatic phase of human immunodeficiency virus 1 (HIV-1) infection the lymphatic tissues seem to function as a major reservoir of HIV. We have examined the viral load in peripheral blood mononuclear cells (PBMC) and lymph node mononuclear cells (LNMC) of 12 naturally and 4 experimentally long-term simian Immunodeficiency virus (SIV)-infected African green monkeys (AGM) to help explain the apathogenicity of the AGM isolates of SIV (SIVagm) in their natural host. The mean number of SIVagm producing cells determined by limiting dilution assay was found to be 1.7 +/- 2.2 and 2.1 +/- 3.3 per 10(5) PBMC or LNMC, respectively. Similarly, polymerase chain reaction analysis of serially diluted cells showed the mean provirus carrying cell number to be 2.8 +/- 3.7 per 10(5) PBMC and 4.0 +/- 5.5 per 10(5) LNMC. When normalized for CD4+ cells the provirus and infectious virus loads in the LNMC and PBMC were also similar. No trapping of virus particles could be detected by in situ hybridization or immunohistochemistry. The data demonstrate that in contrast to HIV-1-infected humans, the viral burden in the lymph nodes of long-term SIV(agm)-infected AGMs is comparable to that in the PBMC.

Protection from pathogenic SIVmac challenge following short-term infection with a nef-deficient attenuated virus

Infection of rhesus macaques with attenuated SIVmac is, at present, the only strategy which confers significant protection from challenge with wild-type SIVmac grown in monkey PBMC. However, initial results suggest that the protective mechanism does not develop until late after "vaccination" (approx 10 months). As part of a European study using the C8 variant of SIVmac251-32H (containing an in-frame 12-bp deletion in the nef gene), we wished to determine (a) if protection could be achieved against challenge with a "swarm" of SIVmac251-32H produced in monkey cells and (b) if protection could be demonstrated after a short period of infection with the attenuated virus. Eight Indian rhesus macaques were infected with C8 and four were challenged after 10 weeks with 50 MID50 of an uncloned stock of SIVmac251-32H grown in rhesus cells, and the other four were challenged after 20 weeks. Four animals served as naive controls. Three of the four monkeys challenged at 10 weeks and three of those challenged at 20 weeks were protected from productive superinfection. From one monkey in each group it was, however, possible to demonstrate the presence of the wild-type provirus in monkey PBMC by diagnostic PCR and anamnestic immune response. There was no apparent correlation between the levels of binding or neutralizing antibodies on the day of challenge and subsequent protection. Approximately 1 year after infection with the attenuated virus all monkeys were rechallenged with the heterologous SIVsm strain, first with 10-20 MID50 and then with 1000 MID50. Although not all of the SIVsm-inoculated naive controls became productively infected, PCR analysis failed to reveal any evidence for infection of the "immunized" monkeys.

Determination of gamma/delta and other T-lymphocyte subsets in bronchoalveolar lavage fluid and peripheral blood from patients with sarcoidosis and idiopathic fibrosis of the lung

We measured five different lymphocyte subpopulations, including gamma/delta-T cells, in peripheral blood and bronchoalveolar lavage (BAL) fluid from 48 consecutive patients undergoing diagnostic BAL (patients with sarcoidosis (n = 19), patients with idiopathic pulmonary fibrosis (IPF; n = 11) and patients with other diseases of the lung). Quantitative analysis of CD3+, CD4+, CD8+, CD16/56+ cells and gamma/delta-T cells was done by flow cytometry. The proportion of CD3+ and CD4+ cells in the peripheral blood of patients with sarcoidosis and IPF was significantly diminished, while CD8+ lymphocytes and NK cells were significantly elevated compared to healthy controls. There was no significant difference for the gamma/delta-T cell subpopulation between patients with sarcoidosis, IPF and control group. The proportion of CD3+ and CD4+ cells in BAL fluid was significantly elevated in sarcoidosis compared to IPF, while CD8+ cells were significantly diminished. Natural killer cells, defined as CD16/56+ CD3- cells, showed comparable low numbers in sarcoidosis and IPF. For gamma/delta-T cells no significant difference was found between patients with sarcoidosis and IPF.

Rapid screening for Mamu-A1-positive rhesus macaques using a SIVmac Gag peptide-specific cytotoxic T-lymphocyte assay

As part of an ongoing vaccine study using peptide immunogens designed to stimulate simian immunodeficiency virus (SIV)mac-specific cytotoxic T lymphocytes (CTL) it was necessary to identify rhesus macaques within our colony bearing the Mamu-A1 major histocompatibility complex (MHC) class I haplotype. Peripheral blood mononuclear cells (PBMC) from individual monkeys were analysed by immunoelectrofocusing for the presence of a band corresponding to the Mamu-A1 molecule. In addition, PBMC were pulsed with the SIVmac Gag peptide 11 (against which CTL are Mamu-A1 restricted) and analysed for susceptibility to lysis by peptide 11-specific CTL. PBMC from all of the rhesus macaques shown to be Mamu-A1 positive by immunoelectrofocusing were highly sensitive to lysis by the peptide 11-specific CTL. A total of 46% (16 from 35) of the rhesus macaques originating from India were found to be Mamu-A1 positive, whereas none of the Chinese rhesus (0 from 37) macaques possessed this haplotype. Once a peptide-specific CTL is established, screening by CTL assay offers a faster, reliable and more relevant alternative to immunoelectrofocusing for selecting monkeys for use in vaccination trials.