Aspergillus nomius, an important aflatoxin producer in Brazil nuts?

The relationship between aflatoxin B1 and G1 was examined in samples from 199 aflatoxin contaminated lots of inshell Brazil nuts imported to Europe. In most of the samples, the relationship between B1 and G1 were approximately 50/50 indicating that the major responsible aflatoxin producing fungi cannot be Aspergillus flavus, which produces solely B aflatoxins. Fungal strains were isolated from two batches of Brazil nuts and isolates of both A. nomius and A. flavus could be identified. The A. nomius isolates were good producers of both B and G aflatoxins, while the A. flavus strains only produced B aflatoxins. In conclusion, this study suggests that A. nomius is an important producer of aflatoxins in Brazil nuts and that its occurrence, and possibly other B and G aflatoxin producers, should be further examined since this may influence strategies for prevention and control of aflatoxins in Brazil nuts.

Growth of aflatoxigenic moulds and aflatoxin formation in Brazil nuts

The present study aimed at gaining more knowledge of the growth of aflatoxigenic moulds and aflatoxin production in Brazil nuts in relation to humidity conditions and storage time. For this purpose, the growth of aflatoxigenic moulds and the increase in aflatoxin levels in Brazil nuts was studied in the laboratory at temperature and humidity conditions that are relevant for the Amazon region. Fresh unprocessed Brazil nuts in shell were inoculated with an aflatoxin producing strain of Aspergillus nomius previously isolated from Brazil nuts. The nuts were stored at 27 °C in combination with 97, 90 or 80% surrounding relative humidity in a respirometer for up to 3 months. The General Linear Model (GLM) was used for evaluation of the effect of water activity and time on aflatoxigenic mould levels and on aflatoxin levels, as well as the relationship between mould and aflatoxin levels. During storage at the highest relative humidity (97%) aflatoxin formation occurred rapidly, whereas storage at 90% relative humidity resulted in slower aflatoxin formation. At the lowest relative humidity (80%), aflatoxin formation occurred sporadically during storage. The increase in mould and aflatoxin levels along the production chain is also described, using field data collected in the state of Para, Brazil. The growth of aflatoxigenic moulds and aflatoxin formation increased rapidly between 40-90 days following collection of the nuts, before the nuts reached the final drying stage at the processing plant. In addition, a logistic regression model predicting the probability that the European legislative limit of 4 µg/kg for aflatoxins in nuts will be exceeded in relation to colony counts of either one selected aflatoxigenic mould strain (laboratory experiments) or of a mixture of aflatoxigenic strains (field data) was developed. The probability that total aflatoxin levels will exceed the European legislative limit of 4 µg/kg increased rapidly from approx. 30% to above 80% for both experimental and field samples at mould levels between 2 and 3 log cfu/g.

Tuberculosis-HIV co-infection: policy and epidemiology in 25 countries in the WHO European region

OBJECTIVES

The aims of this study were to collect and review tuberculosis (TB)-HIV data for Europe and to provide an overview of current health policies addressing co-infection.

METHODS

We collected reported cases of TB-HIV from the 25 most affected member states of the World Health Organization (WHO) European region. Countries were also asked whether they had implemented health policies covering collaborative TB-HIV activities and what their main achievements, obstacles and needs were in addressing TB-HIV.

RESULTS

Twenty countries reported registering a total of 6925 TB-HIV cases in 2005. Among TB patients tested, 3.3% were found to be HIV-positive, up from 2.1% in 2004. The male-to-female ratio was 2.7:1. The largest percentage of co-infections were reported in people aged 25-34 years (47.8%). Recommended TB-HIV policies have been implemented in many of the countries.

CONCLUSIONS

Case-finding has improved in many countries and the reported incidence of TB-HIV is increasing in the European region, particularly among young adults, although it remains low compared to other parts of the world. Strengthened coordination of existing TB and HIV services is still needed.

Widespread Outbreak of Cucurbit yellow stunting disorder virus in Melon, Squash, and Watermelon Crops in the Sonoran Desert of Arizona and Sonora, Mexico

Bright yellow, interveinal chlorosis was observed for the first time on leaves of the older and mid-growth of cucurbit plants in southern Arizona and Sonora (Mexico) during September and October of 2006. Some cultivars exhibited substantial yield losses of 30 to 80%. In Arizona, symptoms were in Cucumis melo (muskmelon and honeydew melon) fields in the Yuma Valley and Hyder. In Sonora, honeydew and muskmelon, Cucurbita pepo (acorn, spaghetti, and summer [yellow and zucchini] squash), and Citrullus lanatus (watermelon) were symptomatic in Hermosillo, whereas, in Caborca, honeydew and cantaloupe developed similar symptoms. Interveinal chlorosis was observed in 60 to 100% of the plants in each field. Crops planted mid-to-late season were 100% infected, whereas, the early-season fields experienced approximately 60 to 80% incidence. All symptomatic fields in the Sonoran Desert and vicinity were infested by the whitefly Bemisia tabaci (Genn.), which was identified as the 'B biotype' on the basis of mitochondria COI sequence analysis (data not shown). Whitefly population levels were variable and ranged from 5 to 200 per plant. Total RNA was isolated from leaf samples collected from symptomatic plants using Tri Reagent (Molecular Research Center, Cincinnati, OH). Purified RNA was used in reverse transcriptase-PCR with primers specific to the Cucurbit yellow stunting disorder virus (CYSDV) coat protein (CP) gene (RNA2-deoxyribonucleotide coordinates 4927-4950 and 5657-5679) for the suspected whitefly-transmitted bipartite CYSDV (4). PCR yielded the CYSDV CP fragment, at 753 bp (GenBank Accession Nos. EF21058 and EF21059), which was cloned into pGEM T-Easy and sequenced in both directions using universal primers. The CYSDV CP nucleotide sequences (n = 16) obtained from acorn squash, honeydew melon, muskmelon, yellow squash, and watermelon had 99 to 100% identity. The Arizona (AZ) and Sonora (SON) CYSDV CP sequences shared 99 to 100% identity with previously described CYSDV isolates from the Eastern Hemisphere (GenBank Accession Nos. DQ903105 and DQ903108) and also with two isolates of CYSDV collected during 2004 from Zacapa Valley, Guatemala (GenBank Accession Nos. EF21060 and EF21061) (J. K. Brown, unpublished data). CYSDV is a member of the genus Crinivirus, family Closteroviridae. CYSDV was first identified in cucumber and melon crops in the Middle East approximately 15 years ago and 10 years ago in Spain (1). Most recently, this virus was introduced into Texas (2), Guatemala (J. K. Brown, unpublished data), and Arizona and California (3). CYSDV has therefore emerged as an important and potentially worldwide threat to the production of cultivated cucurbits (3). The threat appears to be significant in light of the introduction or establishment of the exotic B. tabaci biotypes B and Q vectors, which also originated in the Middle Eastern-North African-Mediterranean region. To our knowledge, this is the first report of CYSDV infecting field-grown C. pepo (four types) and watermelon, reported previously only as experimental laboratory hosts, and of CYSDV in two types of melon (C. melo) in Mexico. References: (1) A. Celix et al. Phytopathology 86:1370, 1996. (2) J. Kao et al. Plant Dis. 84:101, 2000. (3) Y.-W. Kuo et al. Plant Dis. 91:330, 2007. (4) L. Rubio et al. J. Gen. Virol. 82:929, 2001.

Selecting and deselecting imatinib-resistant clones: observations made by longitudinal, quantitative monitoring of mutated BCR-ABL

Resistance to imatinib during the treatment of chronic myeloid leukaemia (CML) is frequently associated with point mutations in the ABL gene encoding the ATP binding region likely to cause disease relapse. Early diagnosis and monitoring of these mutations may be important in order to prevent rapid expansion of resistant clones. We describe a quantitative mutation-specific PCR assay based on the readily available Taqman platform. Selectivity for the mutated target is conferred by mutation-specific primers destabilised by additional mismatches. The assay can be carried out in parallel to standard BCR-ABL quantification and is therefore more quickly compared to standard sequencing procedures. The sensitivity of the assay reaches 0.1%. It also allows for quantitative assessment of mutated clones. By analysing sequential samples of resistant subjects, we show how mutated clones were selected, maintained or deselected depending on the individual treatment setting. The high sensitivity and practical merits of this method makes it a good candidate for prospective molecular surveillance of patients at high risk for imatinib resistance.

Requisite role for complement C5 and the C5a receptor in granulomatous response to mycobacterial glycolipid trehalose 6,6'-dimycolate

The development of pulmonary granulomatous lesions during mycobacterial infection is a complex phenomenon, in part caused by responses elicited towards the surface glycolipid trehalose 6,6'-dimycolate (TDM; cord factor). The molecular mechanisms underlying granuloma formation following challenge with TDM are not yet completely understood. The present study defines pathologic differences in acute response to Mycobacterium tuberculosis TDM in C57BL/6 mice and mice lacking the C5a receptor (C5aR-/-). Mice were intravenously injected with TDM prepared in water-in-oil-in-water emulsion and examined for histologic response and changes in proinflammatory cytokines and chemokines in lung tissue. Control C5a receptor-sufficient mice demonstrated a granulomatous response that peaked between days 4 and 7. Increased production of macrophage inflammatory protein-1 alpha (MIP-1alpha), interleukin-1beta (IL-1beta) and CXC chemokine KC (CXCL1) correlated with development of granulomas, along with modest change in tumor necrosis factor-alpha (TNF-alpha). In contrast, the C5aR-/- mice revealed markedly exacerbated inflammatory response. The receptor-deficient mice also demonstrated a lack of coherent granulomatous response, with severe oedema present and instances of lymphocytic cuffing around pulmonary vessels. Lung weight index was increased in the C5aR-/- mice, correlating with increased MIP-1alpha, KC, IL-1beta and TNF-alpha over that identified in the congenic C5aR-sufficient controls. Correlate experiments performed in C5-deficient (B10.D2-H2d H2-T18c Hco/oSnJ) mice revealed similar results, leading to the conclusion that C5 plays a significant role in mediation of chemotactic and activation events that are the basis for maturation of granulomatous responses to TDM.

Consumers' ability to discriminate aflatoxin-contaminated Brazil nuts

The objectives of the study were to investigate the extent to which consumers can separate nuts with a high content of aflatoxin from sound nuts, and whether sorting results can be improved by information or whether they are affected by certain factors. A test panel consisting of 100 subjects was asked to crack 300 g Brazil nuts and to sort the nuts into those they considered edible and inedible. The test showed that consumers can, on current behaviour, discriminate aflatoxin-contaminated Brazil nuts to a significant extent. The median and the 95th percentile of the total concentrations of aflatoxins (B1, B2, G1, G2) in the samples before sorting were 1.4 and 557 microg kg(-1), respectively, and in the edible fractions after sorting 0.4 and 56 microg kg(-1), respectively. Given that levels of aflatoxins before sorting exceed either 2 microg aflatoxin B1 kg(-1) or totally 4 microg aflatoxins kg(-1), there was no effect of aflatoxin concentrations before sorting on the probability of exceeding these thresholds in the edible fraction. This means that similar sorting results were obtained for samples with aflatoxin levels exceeding either of the two thresholds, irrespective of if the thresholds were exceeded with a few microg kg(-1) or up to more than 1000 microg kg(-1). None of the tested factors (such as sex, age, level of education, ethnic background or knowledge of mycotoxins) had any effects on the probability of exceeding either of the two aflatoxin thresholds.

Predicting noncompliant levels of ochratoxin A in cereal grain from Penicillium verrucosum counts

AIMS

To model the probability of exceeding the European legislative limit of 5 microg ochratoxin A (OTA) per kilogram grain in relation to Penicillium verrucosum levels and storage conditions, and to evaluate the possibilities of using P. verrucosum colony counts for predicting noncompliant OTA levels.

METHODS AND RESULTS

Cereal samples were inoculated with P. verrucosum spores and stored for up to 9 months at temperatures and water activities ranging from 10-25 degrees C and aw 0.77-0.95. A logistic regression analysis showed that the probability of exceeding 5 microg OTA kg(-1) grain was related to colony counts of P. verrucosum and water activity. The sensitivity and specificity of various P. verrucosum count thresholds for predicting noncompliant OTA levels were estimated, using data from the storage trial and natural cereal samples.

CONCLUSION

The risk of exceeding 5 microg OTA kg(-1) grain increased with increasing levels of P. verrucosum, and with increasing water activities. A threshold of 1000 CFU P. verrucosum per gram grain is suggested to predict whether or not the legislative limit is exceeded.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study has provided a tool to evaluate the levels of P. verrucosum in grain in relation to OTA levels. Hence, mycological analyses can be used to identify cereal samples with high risk of containing OTA levels above the legislative limit.

Variation in the classification of polyneuropathies among European physicians

OBJECTIVE

Considerable debate still exists regarding the classification of polyneuropathies (PNPs) into predominantly demyelinating, predominantly axonal loss, mixed or unclassified. This study was designed to determine the variation among physicians in the classification of PNPs by using the European Standardized Telematic tool to Evaluate Electromyography knowledge-based systems and Methods (ESTEEM) multicenter database.

METHODS

Seven physicians from 6 laboratories in Europe sent a total of 156 prospectively collected cases of PNP with electromyography (EMG) data including diagnosis (examination diagnosis) to the database. Each physician interpreted the electrophysiological data from all cases (interpretation diagnosis) and a final diagnosis was given at the consensus meetings of the group (consensus diagnosis).

RESULTS

Comparison of each physician's examination diagnosis with his/her interpretation diagnosis, i.e. intra-physician variation, showed a change towards less classified PNPs (P < 0.05). Interpretation diagnoses showed large inter-physician variation in the classification of PNPs. The consensus group was more cautious than individual physicians in classifying PNPs as mixed and axonal. The probability of the consensus diagnosis increased with increasing number of abnormal motor and sensory segments tested.

CONCLUSIONS

Recognition of variation in classification of PNP as shown in this study and suggesting standards of good clinical practice developed by a consensus group may increase the quality of EMG practice.

Dysregulated response to mycobacterial cord factor trehalose-6,6'-dimycolate in CD1D-/- mice

The biologic effects of the mycobacterial glycolipid trehalose-6,6'-dimycolate (TDM) include granuloma formation and macrophage activation and are dependent on physical conformation. In mice, the group II CD1 surface molecule CD1d has been implicated in glycolipid presentation. The importance of CD1d interactions in pathology has yet to be established. We hypothesized that mice lacking CD1d (CD1D(-/-)) would demonstrate dysregulated granulomatous response to TDM, compared with CD1D(+/-) heterozygous controls. Mice were intravenously injected with TDM-coated polystyrene-divinylbenzene beads and examined for histologic response and for changes in inflammatory cytokine and chemokine mRNA. Control CD1D heterozygous mice demonstrated a granulomatous response, which peaked at day 5. Increased mRNA for tumor necrosis factor-alpha (TNF-alpha) and macrophage inflammatory protein-1alpha (MIP-1alpha) correlated with development of granulomas, with very little change in interleukin-1beta (IL-1beta) and monocyte chemoattractant protein-1 (MCP-1). In contrast, the CD1D(-/-) mice revealed markedly different responses. Five days after administration, severe pulmonary hemorrhage was induced. The relative size of inflammation surrounding coated bead in the CD1D(-/-) mice was nearly double that induced in the CD1D(+/-) mice. CD1D(-/-) mice also demonstrated elevated mRNA for both inflammatory cytokines and chemokines by day 1 after administration, significantly earlier than responses seen in the heterozygous controls.

Levels of ochratoxin A in blood from Norwegian and Swedish blood donors and their possible correlation with food consumption

Blood levels of ochratoxin A were determined in 406 Scandinavian blood donors (206 from Oslo, Norway, and 200 from Visby on the island of Gotland, Sweden), using an HPLC method. In connection with the blood collection, the subjects were asked to fill in a food questionnaire to obtain individual dietary information relevant to ochratoxin A exposure. The mean plasma level of ochratoxin A was 0.18 ng/ml in Oslo and slightly higher, 0.21 ng/ml (P=0.046) in Visby. There was no correlation between plasma levels of ochratoxin A and the estimated total dietary intake of ochratoxin A based on consumption data and levels in food (retrieved from the literature), neither was the plasma level of ochratoxin A correlated with the total amount of food consumed. However, consumption of several foods, including cereal products, wine, beer and pork, were to some minor degree related to high plasma levels of ochratoxin A. The strongest correlations (correlation coefficient r>0.4; P<0.001) were observed for women in relation to the consumption of beer or medium brown bread. Correlation analysis of combinations of two or more food categories did not result in any statistically significant correlation.

Performance of mycological media in enumerating desiccated food spoilage yeasts: an interlaboratory study

Dichloran 18% glycerol agar (DG18) was originally formulated to enumerate nonfastidious xerophilic moulds in foods containing rapidly growing Eurotium species. Some laboratories are now using DG18 as a general purpose medium for enumerating yeasts and moulds, although its performance in recovering yeasts from dry foods has not been evaluated. An interlaboratory study compared DG18 with dichloran rose bengal chloramphenicol agar (DRBC), plate count agar supplemented with chloramphenicol (PCAC), tryptone glucose yeast extract chloramphenicol agar (TGYC), acidified potato dextrose agar (APDA), and orange serum agar (OSA) for their suitability to enumerate 14 species of lyophilized yeasts. The coefficient of variation for among-laboratories repeatability within yeast was 1.39% and reproducibility of counts among laboratories was 7.1%. The order of performance of media for recovering yeasts was TGYC > PCAC = OSA > APDA > DRBC > DG 18. A second study was done to determine the combined effects of storage time and temperature on viability of yeasts and suitability of media for recovery. Higher viability was retained at -18 degrees C than at 5 degrees C or 25 degrees C for up to 42 weeks, although the difference in mean counts of yeasts stored at -18 degrees C and 25 degrees C was only 0.78 log10 cfu/ml of rehydrated suspension. TGYC was equal to PCAC and superior to the other four media in recovering yeasts stored at -18 degrees C, 5 degrees C, or 25 degrees C for up to 42 weeks. Results from both the interlaboratory study and the storage study support the use of TGYC for enumerating desiccated yeasts. DG18 is not recommended as a general purpose medium for recovering yeasts from a desiccated condition.

Dietary intake of some important mycotoxins by the Swedish population

To estimate the intake of some mycotoxins from food in Sweden, approximately 600 samples were collected and analysed for aflatoxins, ochratoxin A, patulin and trichothecenes. Intakes were calculated for average and high consumers among adults and children and compared with the tolerable daily intake (TDI) of the respective toxin. Mycotoxin levels in the food samples were generally below the European/national maximum limits. However, high levels of aflatoxins were found in some samples of Brazil nuts and pistachios. The intake of ochratoxin A, patulin and trichothecenes was found to be below the temporary, TDI values (tTDI) proposed for these toxins by international expert groups, although the intake of trichothecenes (expressed as T-2 toxin equivalents) in children with a high consumption of cereals was close to the tTDI for T-2 toxin. Since there is to date no established numerical tTDI for aflatoxins, such a value was estimated for use within the project. The calculated intake of aflatoxins in high consumers exceeded this tTDI by a factor of two. In conclusion, the exposure to mycotoxins in Sweden did not generally, give rise to any major health concerns in the present study. However, the high levels of aflatoxins in certain commodities emphasize the need for preventive measures and improved control of toxin levels in these food items. Furthermore, the need for regulatory levels for trichothecenes in cereal products should be evaluated.

The Fab fragment of anti-digoxin antibody (digibind) binds digitoxin-like immunoreactive components of Chinese medicine Chan Su: monitoring the effect by measuring free digitoxin

Chan Su, a Chinese medicine prepared from the skin glands of Chinese toads, is used in the treatment of cardiovascular diseases. Severe toxicity and even death has been reported from overdose with Chan Su. The cardiotonic effect of Chan Su is attributed to bufadienolides, which also have apparent digitoxin activity. We demonstrated that these components of Chan Su could be neutralized by digibind, both in vitro and in vivo. For in vitro experiments, we supplemented drug-free serum pools with aqueous extract of Chan Su. Then, to aliquots of serum pool containing Chan Su, various amounts of digibind (10, 25 or 50 microg/ml of serum) were added. After incubation, total and free digitoxin concentrations (in the protein-free ultrafiltrate) were measured using the fluorescence polarization immunoassay (FPIA) and a FLX/TDx analyzer. For in vivo experiments, mice were fed with Chan Su by gavage. After 45 min, 200 microg of digibind was administered by injection. Fifteen minutes after injection, blood was collected for analysis of total and free apparent digitoxin activities. We observed complete removal of apparent digitoxin activity from protein-free ultrafiltrate both in vitro and in vivo by digibind, indicating that digibind successfully binds Chan Su. We conclude that digibind neutralizes Chan Su, and measuring the free digitoxin concentrations can monitor such an effect.

Significantly improved oral uptake of amikacin in FVB mice in the presence of CRL-1605 copolymer

Amikacin is an aminoglycoside which is used in the treatment of infection from gram negative bacteria. Amikacin is also used synergistically with penicillin against gram positive cocci. Amikacin cannot be delivered orally probably due to efflux of drug by P-glycoprotein pump in the brush border of intestine. We studied the possibility of delivering amikacin orally in mice using a copolymer (CRL-1605) as a vehicle. This copolymer inhibits P-glycoprotein pump. Two different doses of amikacin were used (500 mg/kg and 100 mg/kg). The concentration of polymer used was 132 mg/kg. The liquid formulation was fed to mice by gavage and serum amikacin concentrations were estimated after one hour and two hours using fluorescence polarization immunoassay. We observed a two fold increase in serum amikacin concentration when amikacin was orally delivered in the presence of CRL-1605 compared to controls (amikacin alone). We conclude that gastrointestinal absorption of amikacin is significantly increased in the presence of CRL-1605 in mice.

Digitoxin-like immunoreactivity in sera of mice after feeding with chinese medicine Chan Su: study of protein binding of Chan Su in normal sera, uremic sera and sera from patients with liver disease

Traditional Chinese medicines are readily available without prescription from herbal drug stores. One such Chinese medicine, Chan Su, which is prepared from the skin gland of toads, has cardiotonic effect due to bufadienolides. Here we report rapid detection of the presence of Chan Su in blood using the fluorescence polarization immunoassay for digitoxin. In our study mice were fed with a dose of 75 mg/kg of Chan Su and blood was drawn before, and 1 and 2 h after feeding. We observed significant digitoxin-like immunoreactivity in the sera. For example in one mouse the digitoxin-like immunoreactivity was undetectable before feeding with Chan Su, but was 19.7 ng/ml 1 h and 8.8 ng/ml 2 h afterwards. The apparent half-life of Chan Su is approximately 1 h in mice. In another experiment, we studied protein binding of Chan Su by measuring total and free Chan Su concentrations (ultrafiltrate prepared by using Centrifree Micropartition Filter, molecular weight cutoff: 30000 Da). Chan Su was strongly bound to serum proteins. We observed higher free fraction in uremic sera and sera from patients with liver disease. We identified albumin as one of the proteins that bind Chan Su in serum.

Characterizing the production of a wild-type and benomyl-resistant Fusarium lateritium for biocontrol of Eutypa lata on grapevine

Benomyl-resistant (BR) and wild-type (WT) strains of Fusarium lateritium were examined for their tolerance to benomyl on potato dextrose agar (PDA) containing benomyl and control of the Eutypa lata in grapevine bioassays. The WT strain grew on PDA containing 1 microg/ml benomyl at 13, 26 and 29 degrees C. The BR strain grew on PDA containing 10 microg/ml benomyl at 4 degrees C, on PDA containing 100 microg/ml benomyl at 29 degrees C, and on PDA containing 1,000 microg/ml benomyl at 13 degrees C and 26 degrees C. The BR strain was also able to colonize grapevine segments and control E. lata in the presence of 1,000 microg/ml benomyl. Both strains were amenable to production via liquid fermentation and both achieved 100% control of E. lata in grapevine bioassays. Neither the duration of fermentation nor incubation temperature during grapevine bioassays influenced the efficacy of either strain against E. lata. The results suggest that application of BR F. lateritium alone or in combination with benomyl may provide good control of E. lata.

Cytokine message and protein expression during lung granuloma formation and resolution induced by the mycobacterial cord factor trehalose-6,6'-dimycolate

Trehalose-6,6'-dimycolate (TDM), or cord factor, is a mycobacterial cell wall component that induces granuloma formation and proinflammatory cytokine production in vivo and in vitro. The purpose of this work was to better understand the mechanisms by which TDM promotes lung granuloma formation. This was accomplished by characterizing cytokine mRNA expression during TDM-induced alveolitis culminating in cohesive granuloma development. A single intravenous injection of TDM given to C57BL/6 mice produced lung granulomas that peaked in number 5 days after challenge and were nearly resolved by 14 days. mRNA in whole lung preparations was quantitated by bioluminescent RT-PCR. Tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and IL-6 were significantly elevated during granuloma development and decreased during granuloma resolution. There were no detectable changes in mRNA for interferon-y (IFN-y), IL-2, IL-4, IL-5, IL-10, and IL-12(p40). The level of TNF-alpha protein extracted from lung minces highly correlated with morphologic indices of granulomatous inflammation, indicating that it may be an important modulator of the inflammatory intensity induced by TDM. TDM may interact specifically with macrophages in vivo, as evidenced by induction of TNF-alpha, IL-1beta, and IL-6, but not IFN-gamma, protein in bone marrow-derived macrophages from C57BL/6 mice. TDM may therefore play an important role early in macrophage activation during the host granulomatous response to mycobacteria.