The ETS Family Transcription Factors Etv5 and PU.1 Function in Parallel To Promote Th9 Cell Development

The IL-9-secreting Th9 subset of CD4 Th cells develop in response to an environment containing IL-4 and TGF-β, promoting allergic disease, autoimmunity, and resistance to pathogens. We previously identified a requirement for the ETS family transcription factor PU.1 in Th9 development. In this report, we demonstrate that the ETS transcription factor ETS variant 5 (ETV5) promotes IL-9 production in Th9 cells by binding and recruiting histone acetyltransferases to the Il9 locus at sites distinct from PU.1. In cells that are deficient in both PU.1 and ETV5 there is lower IL-9 production than in cells lacking either factor alone. In vivo loss of PU.1 and ETV5 in T cells results in distinct effects on allergic inflammation in the lung, suggesting that these factors function in parallel. Together, these data define a role for ETV5 in Th9 development and extend the paradigm of related transcription factors having complementary functions during differentiation.

Ethnomedicinal uses of plants in the treatment of paediatric geohelminth infections in Kalat district of Northern Balochistan, Pakistan

ETHNOPHARMACOLOGICAL RELEVANCE

Infection by intestinal parasitic worms (soil-transmitted helminths or geohelminths) is prevalent in many parts of the world, and poses a particular health risk to children. This paper presents findings from a preliminary study with the primary aim to document indigenous knowledge about the use of herbal medicines in the treatment of intestinal worm infections in children among the local communities of Kalat district of northern Balochistan, Pakistan.

MATERIALS AND METHODS

Ethnomedicinal data were collected through a triangulation approach, that included participant-observation and rapid appraisal methods. Prior-informed consent (PIC) was obtained from participants before conducting structured and semi-structured interviews and delivering an open ended questionnaire. A total of 94 participants, including 28 men (of whom 7 were traditional healers), and 66 women of four different age groups were interviewed. Results were analyzed using quantitative indices of Use Value citations (UVC) and Disease-Consensus Index (DCI).

RESULTS

Fewer men than women agreed to be interviewed, thus overall women in the area appeared to have more ethnomedicinal knowledge. The majority of study participants belonged to the older age group (>55 years). A total of 49 plant species, belonging to 47 genera, distributed in 30 families were reported. The families Asteraceae and Lamiaceae were most frequently represented, with four species each. Trees were the most common life form, with seeds the most frequently cited plant part used (29%). Nearly a third (31%) of plant-based remedies reported in the treatment of intestinal worms were administered as a decoction. The highest UVC and DCI was reported for the species Ferula assa-foetida sL. (UVC 0.51, DCI 0.46).

CONCLUSIONS

This study provides previously unreported data on the use of medicinal plants in the treatment of geohelminth infections in children of Kalat. Eight species, Acacia modesta Wall., Asparagus capitatus Baker, Microcephala lamellata (Bunge) Pobed., Nepeta praetervisa Rech.f., Plantago ciliata Desf., Pistacia atlantica Desf., Seriphidium quettense (Podlech) Y.R.Ling and Thymus linearis Benth. are reported here as anthelmintics for the first time. Detailed studies on the anthelmintic activity of chemical constituents of these species are lacking from existing literature. Further phytochemical, pharmacological and toxicity studies are required in order to evaluate the efficacy and safety of these newly reported anthelmintic species. These plants may provide a source of novel anthelmintic drug leads, which are urgently required due to the problem of global anthelmintic resistance.

The endemic medicinal plants of Northern Balochistan, Pakistan and their uses in traditional medicine

ETHNOPHARMACOLOGICAL RELEVANCE

The highlands of Northern Balochistan are the hot spots of medicinal and endemic plant in Pakistan. These plants are still commonly used for medicinal purposes by local people in their daily lives. This study first documented the information about the medicinal uses of endemic species of Balochistan-province Pakistan.

MATERIALS AND METHODS

A survey was performed using open ended questionnaires, free listening and personal observations with 152 informants (54% female, 46% male). In addition, the use value (MUV), use report (UR), fidelity level (FL), frequency citation (FC), relative frequency citation (RFC), family importance value (FIV) of species were determined and the informant consensus factor (ICF) was calculated for the medicinal plants included in the study.

RESULTS

A total of 24 endemic plants belonging to 19 genera and 14 families were used by the local inhabitants to treat 12 categories of various diseases. The most common families of endemic plant species as depicted by its number of species (6 species) and FIV (9.9) was Fabaceae as the dominant family. The endemic plant species comprised perennial herbs (30%), annual herbs (25%), shrubs (29%) and under shrubs (16% each), no endemic tree species was reported in the study area. The highest number of species were used in the treatment of gastrointestinal diseases (12 species). The main route of administration is oral injection (62%) while the most frequently used form of external administration of herbal medicine was paste (5.4%) and the most commonly applied methods of preparation are powder (48.2%). Highest use report were calculated for Allium baluchistanicum and Viola makranica, (8 UR each), and least use report were calculated for two species Heliotropium remotiflorum and Tetracme stocksii (1 UR for each). Use values of the recorded plant species have been calculated which showed a highest use value of (0.73) for A. baluchistanicum and (0.56) for Berberis baluchistanica while the lowest UVs were attained for T. stocksii (0.13). Highest RFC value were calculated for Achillea millefolium (0.19) and least RFC were calculated for Blepharis sindica (0.02). The endemic species with 100% fidelity level was calculated for two plant species i.e. Seriphidium quettense and B. baluchistanica.

CONCLUSIONS

The Balochistan is rich in endemic and other medicinal plants, still needs more exploration and study. Thus, it is important to document and reconstitute the remainders of the ancient medical practices which exist in Balochistan and other areas of the world, and preserve this knowledge for future generations. The endemic species which are used in traditional medicine in the region lacks phototherapeutic evidence. It is necessary to perform phytochemical or pharmacological studies to explore the potential of plants used for medicinal purposes. Overgrazing, urbanization and unsustainable harvesting of such rare and endemic medicinal plants in this region is facing severe threats of extinction. It is thus recommended that cultivation techniques be formulated, especially for the most important endemic plant medicinal species of the region.

PU.1 Expression in T Follicular Helper Cells Limits CD40L-Dependent Germinal Center B Cell Development

PU.1 is an ETS family transcription factor that is important for the development of multiple hematopoietic cell lineages. Previous work demonstrated a critical role for PU.1 in promoting Th9 development and in limiting Th2 cytokine production. Whether PU.1 has functions in other Th lineages is not clear. In this study, we examined the effects of ectopic expression of PU.1 in CD4(+) T cells and observed decreased expression of genes involved with the function of T follicular helper (Tfh) cells, including Il21 and Tnfsf5 (encoding CD40L). T cells from conditional mutant mice that lack expression of PU.1 in T cells (Sfpi1(lck-/-)) demonstrated increased production of CD40L and IL-21 in vitro. Following adjuvant-dependent or adjuvant-independent immunization, we observed that Sfpi1(lck-/-) mice had increased numbers of Tfh cells, increased germinal center B cells (GCB cells), and increased Ab production in vivo. This correlated with increased expression of IL-21 and CD40L in Tfh cells from Sfpi1(lck-/-) mice compared with control mice. Finally, although blockade of IL-21 did not affect GCB cells in Sfpi1(lck-/-) mice, anti-CD40L treatment of immunized Sfpi1(lck-/-) mice decreased GCB cell numbers and Ag-specific Ig concentrations. Together, these data indicate an inhibitory role for PU.1 in the function of Tfh cells, germinal centers, and Tfh-dependent humoral immunity.

STAT4 deficiency reduces the development of atherosclerosis in mice

Atherosclerosis is a chronic inflammatory process that leads to plaque formation in large and medium sized vessels. T helper 1 (Th1) cells constitute the majority of plaque infiltrating pro-atherogenic T cells and are induced via IFNγ-dependent activation of T-box (Tbet) and/or IL-12-dependent activation of signal transducer and activator of transcription 4 (STAT4). We thus aimed to define a role for STAT4 in atherosclerosis. STAT4-deficiency resulted in a ∼71% reduction (p < 0.001) in plaque burden in Stat4(-/-)Apoe(-/-) vs Apoe(-/-) mice fed chow diet and significantly attenuated atherosclerosis (∼31%, p < 0.01) in western diet fed Stat4(-/-)Apoe(-/-) mice. Surprisingly, reduced atherogenesis in Stat4(-/-)Apoe(-/-) mice was not due to attenuated IFNγ production in vivo by Th1 cells, suggesting an at least partially IFNγ-independent pro-atherogenic role of STAT4. STAT4 is expressed in T cells, but also detected in macrophages (MΦs). Stat4(-/-)Apoe(-/-)in vitro differentiated M1 or M2 MΦs had reduced cytokine production compare to Apoe(-/-) M1 and M2 MΦs that was accompanied by reduced induction of CD69, I-A(b), and CD86 in response to LPS stimulation. Stat4(-/-)Apoe(-/-) MΦs expressed attenuated levels of CCR2 and demonstrated reduced migration toward CCL2 in a transwell assay. Importantly, the percentage of aortic CD11b(+)F4/80(+)Ly6C(hi) MΦs was reduced in Stat4(-/-)Apoe(-/-) vs Apoe(-/-) mice. Thus, this study identifies for the first time a pro-atherogenic role of STAT4 that is at least partially independent of Th1 cell-derived IFNγ, and primarily involving the modulation of MΦ responses.

Ethnobotany of medicinal plants in district Mastung of Balochistan province-Pakistan

ETHNOPHARMACOLOGICAL RELEVANCE

The aim of this study was to document the medicinal uses of plants in district Mastung of Balochistan province, Pakistan. The ethnobotanical results contain quantitative information on medicinal plants diversity documented for the first time in the area.

MATERIALS AND METHODS

The information was collected through semi-structured interviews, rapid appraisal approach, open ended questionnaire and personal observations. Results were analyzed using quantitative indices of information consent factor (ICF), fidelity level (FL), use value (UV), frequency citation (FC) and relative frequency citation (RFC).

RESULTS

In total of 102 plant species belonging to 47 families were reported for the medicinal purposes. Asteraceae was found to be dominant family in terms of species in the area with 11 species. The whole plant and leaves were noted as most frequently used parts (24%). Decoction (31% with 40 species) was the most commonly used preparation method. Highest ICF value (1) was recorded for antidote category. 100% fidelity level was found for four plant species i.e. Achillea welhemsii, Caralluma tuberculata, Citrullus colocynthis, and Seripidium quettense. The highest use value was reported for the Acroptilon repens (0.5) while highest RFC value was calculated for Berberis balochistanica and Citrullus colocynthis (0.18). Highest use report was calculated for Caralluma tuberculata, Citrullus colocynthis, Malva neglecta and Mentha longifolia with five use reports for each.

CONCLUSIONS

The area is rich in medicinal plants and these plants are still commonly used for medicinal purposes among the people in their daily lives. However, there is a gradual loss of traditional knowledge about these plants in new generation. This study provides basis for the conservation of the local flora, its use as food and medicine. It also provides various socio-economic dimensions associated with the common people.

Chiral Aryl Sulfonyl Hydantoins as Hypoglycemic Agents

Some novel chiral sulfonyl hydantoin derivatives 2a-e and 3 a-e have been prepared. p-Toluenesulfonyl chloride on treatment with L-amino acids in presence of K2CO3/H2O yielded N-(p-toluensulfonyl-)amino acids 1a - e which were cyclized in presence of NH4-SCN Ac2O to afford 1-(p-toluenesulfonyl)-5-substituted-2-thiohydantoins 2a-e. These compounds were oxidized with HNO3 to yield 1-(p-toluenesulfonyl)-5-substituted hydantoins 3a-e. The enantiomeric ratios of 3a-e were determined by 1H NMR spectroscopy using Eu(hfc)3. The antidiabetic activity of 3a-d has been determined.

BATF dependency of Th9-associated genes (HYP7P.290)

Th9 cells are a recently described T helper subset that develops in the presence of TGF-β and IL-4. Th9 cells promote allergic inflammation, anti-tumor immunity, and may contribute to the regulation of auto inflammatory disease. Th9 cells are specialized for IL-9 production and this requires transcription factors including STAT6, PU.1 and IRF4. We have recently described that BATF promotes Th9 development in both mouse and human cells and BATF is required for T cells to promote the development of allergic inflammation. BATF-transduced Th9 cells demonstrated a potent ability to promote allergic inflammation in vivo compared to control transduced Th9 cells. To begin to define the transcriptional network controlling genes in Th9 cells, we characterized the dependence of Th9-enriched genes on each transcription factor, including BATF. Multiple genes including transcription factors, cytokines, and cytokine receptors were BATF-dependent. Unique functional properties of Th9 cells are suggested by the Th9-enriched expression of IL-33R, IL-25R, granzyme A, ephrin A5, and the salt-sensitive serum glucocorticoid kinase. BATF is required for 14/19 genes studied in detail thus far, suggesting that it is a major controller of the Th9 genetic program. Further defining of the module of BATF-dependent genes will aid in integrating the circuitry of Th9 development and function.

T helper 9 (Th9) cellular proliferation and cytokine production is regulated by cAMP responsive element modulator (Crem) (HYP7P.289)

Th9 cells, a CD4+ T cell subset characterized by their robust production of interleukin (IL)-9, can promote allergic inflammation in mice and are associated with atopic disease in humans. Because it might provide targets for therapeutic intervention, it is important to understand the molecular controls governing overall Th9 development and their subsequent effector function. To understand the Th9 transcriptional profile, we recently performed microarray analysis to highlight gene expression enriched in Th9 cells compared to other Th subsets. Crem, which expresses a basic leucine zip domain protein with roles in activating and repressing genes, was among a number of genes with increased expression in Th9 cells. Analysis of mRNA and protein expression among in vitro differentiated Th subsets confirmed Crem was enriched in Th9 cells compared to other subsets. Interestingly, ectopic expression of Crem in Th9 cells repressed their capacity to produce IL-9 upon CD3 re-stimulation while promoting overall cellular proliferation. Crem ectopic expression also promoted cellular expansion in other cultured Th subsets. Conversely, acute siRNA knockdown of Crem mRNA in Th9 differentiated cells resulted in reduced cellular proliferation and enhanced IL-9 production upon CD3 restimulation. Therefore, Crem potentially serves a role in modifying Th9 effector activities upon T cell receptor signaling during allergic disease.

Th9 cell development requires a BATF-regulated transcriptional network

T helper 9 (Th9) cells are specialized for the production of IL-9, promote allergic inflammation in mice, and are associated with allergic disease in humans. It has not been determined whether Th9 cells express a characteristic transcriptional signature. In this study, we performed microarray analysis to identify genes enriched in Th9 cells compared with other Th subsets. This analysis defined a transcriptional regulatory network required for the expression of a subset of Th9-enriched genes. The activator protein 1 (AP1) family transcription factor BATF (B cell, activating transcription factor–like) was among the genes enriched in Th9 cells and was required for the expression of IL-9 and other Th9-associated genes in both human and mouse T cells. The expression of BATF was increased in Th9 cultures derived from atopic infants compared with Th9 cultures from control infants. T cells deficient in BATF expression had a diminished capacity to promote allergic inflammation compared with wild-type controls. Moreover, mouse Th9 cells ectopically expressing BATF were more efficient at promoting allergic inflammation than control transduced cells. These data indicate that BATF is a central regulator of the Th9 phenotype and contributes to the development of allergic inflammation.

A transcription factor network in Th9 cells (P1229)

Th9 cells are the most recent addition to the spectrum of T helper cell subsets that differentiate in the presence of TGF-β and IL-4. Th9 cells promote allergic inflammation, anti-tumor immunity, and may contribute to the regulation of auto inflammatory disease. Whether Th9 cells express a characteristic transcriptional signature has not been determined. To define the identity of Th9 cells, we performed a microarray analysis and identified 629 genes enriched in Th9 cells compared to Th2 and Treg cells. Of these genes, we chose a panel of 14 genes based on potential relatedness to Th9 function, and confirmed Th9-enriched expression in a larger panel of T helper subsets using quantitative PCR. The Th9 enriched genes encoded transcription factors including Erg, Maf, Ahr and Crem, and surface receptors including Il17rb, Ccr4 and Ccr8. Using mice deficient for the transcription factors that promote Th9 development including STAT6, IRF4 and PU.1, we distinguished the impact of each factor on this subset of genes. Thus our data indicates that Th9 cells have an identifiable transcriptional signature, and we have defined a transcription factor network that regulates Th9 gene expression.

Th9 cells secrete BAFF (P1447)

The B-cell activating factor (BAFF) is essential for proper B-cell development. Cells of the innate immune system including macrophages and dendritic cells are the primary source of BAFF. The BAFF protein has two forms, soluble and membrane bound. The membrane bound form of BAFF can become soluble following furin convertase-mediated digestion.. Through microarray analysis comparing the gene profile of Th9, Th2 and T-regulatory cells we found that expression of the gene encoding BAFF (Tnfsf13b) was enriched within the Th9 subset. Using qPCR, intracellular staining, and ELISA, we have confirmed that Th9 cells express BAFF both at the mRNA and protein level. Although Tnfsf13b is expressed at the greatest level in Th9 cells, Th2 cells also express detectable mRNA. Yet, BAFF secretion is only detected in supernatants from Th9 cells. We hypothesized that the absence of soluble BAFF in Th2 supernatants could be due to a difference in the level of Furin expressed by Th9 and Th2 cells. Indeed Th9 cells express a higher level of Furin compared to Th2 cells. Moreover, blocking Furin activity diminishes BAFF secretion from Th9 cells. Together, these data suggest that BAFF production from Th9 cells results from the coordinated expression of both the gene encoding BAFF, and the enzyme required to generate soluble BAFF. Furthermore, Th9 cells may be an important source of BAFF during the development of humoral immunity.

Interleukin-9 is required for allergic airway inflammation mediated by the cytokine TSLP

Thymic stromal lymphopoietin (TSLP) is an epithelial cell-derived cytokine important for the initiation and development of T helper (Th2) cell-mediated allergic inflammation. In this study, we identified a positive association between interleukin-9 (IL-9) and TSLP concentration in the serum of infants with atopic dermatitis. In primary cell cultures, the addition of TSLP led to an increase in IL-9 production from human and mouse Th9 cells, and induced an increase in signal transducer and activator of transcription 5 (STAT5) activation and binding to the Il9 promoter. In vivo, use of an adoptive transfer model demonstrated that TSLP promoted IL-9-dependent, Th9 cell-induced allergic inflammation by acting directly on T cells. Moreover, transgenic expression of TSLP in the lung stimulated IL-9 production in vivo, and anti-IL-9 treatment attenuated TSLP-induced airway inflammation. Together, our results demonstrate that TSLP promotes Th9 cell differentiation and function and define a requirement for IL-9 in TSLP-induced allergic inflammation.

STAT4 isoforms are biomarkers in patients with inflammatory bowel disease (51.2)

Crohn’s disease (CD) and ulcerative colitis (UC), the major forms of inflammatory bowel disease (IBD) in humans are characterized by chronic relapsing inflammation of the gastrointestinal tract (GI). Th1 and Th17 cells have been implicated as important mediators of IBD. Signal transducer and activator of transcription (STAT4) is critical for the development of Th1 cells and promotes IL-17 production from Th17 cells. STAT4 is expressed as two isoforms, a full-length STAT4α, and STAT4β that lacks the C-terminal transactivation domain. In a previous study we found that although both isoforms mediate inflammation in a mouse model of colitis, STAT4β seems more potent in generating tissue inflammation. With this we hypothesized that if STAT4β is more pro-inflammatory, ratios of the isoforms might change in disease. Compared to healthy controls, we observed increased STAT4β/STAT4α ratios in the peripheral blood mononuclear cells of UC and CD patients, correlating with the disease and ratios were normalized after patient treatment. Increased STAT4β/STAT4α ratios in GI biopsies of CD patients further confirmed that ratios correlate with the location and grade of inflammation. In contrast, we did not observe changes in STAT4β/STAT4α ratios in biopsy specimens from eosinophilic esophagitis (EE) patients. Collectively, these data indicate that STAT4 isoforms could be an important non-invasive biomarker in the diagnosis and treatment of IBD, and potentially other inflammatory diseases.

The symphony of the ninth: the development and function of Th9 cells

CD4+ T helper cells are obligate regulators of inflammatory disease. An expanding cadre of T helper (Th) subsets, specialized for promoting particular types of inflammation, function through the secretion of a restricted set of cytokines. The latest addition to the list of subsets is the Th9 cell that secretes IL-9 as a signature cytokine and contributes to several classes of inflammatory disease. In this review we focus on recent advances in understanding the development of Th9 cells, and how Th9 cells contribute to the orchestration of disease.

STAT6-dependent regulation of Th9 development

Th cell effector subsets develop in response to specific cytokine environments. The development of a particular cytokine-secreting pattern requires an integration of signals that may promote the development of opposing pathways. A recent example of this paradigm is the IL-9-secreting Th9 cell that develops in response to TGF-β and IL-4, cytokines that, in isolation, promote the development of inducible regulatory T cells and Th2 cells, respectively. To determine how the balance of these factors results in priming for IL-9 secretion, we examined the effects of each pathway on transcription factors that regulate Th cell differentiation. We demonstrated that TGF-β induces the PU.1-encoding Sfpi1 locus and that this is independent of IL-4-induced STAT6 activation. IL-4-activated STAT6 is required for repressing the expression of T-bet and Foxp3 in Th9 cells, transcription factors that inhibit IL-9 production, and STAT6 is required for the induction of IRF4, which promotes Th9 development. These data established a transcription factor network that regulates IL-9 and demonstrated how combinations of cytokine signals generate cytokine-secreting potential by altering the expression of a panel of transcription factors.

Expanded γδ T cell populations in absence of transcription factor PU.1 (36.49)

T cell development is characterized by a succession of developmental stages that lead to the generation of mature αβ and γδ T cells. γδ T cells are considered innate cells that critically contribute to host defense. PU.1, an Ets family transcription factor, also identified as the spleen focus forming virus proviral integration site-1 (Sfpi-1) is essential for early stages of T cell development and is down regulated during the pro T-cell stage. PU.1 is expressed in Th2 cells but not Th1 cells. Expression of PU.1 in other T cell subsets has not been studied extensively. In this study, we show that PU.1 is expressed in γδ T cells, and in mice that specifically lack PU.1 in T cells using an lck-Cre transgene with a conditional Sfpi1 allele (Sfpilck-/-) there are increased numbers of γδ T cells in spleen, thymus and in the intestine when compared to wild type mice. The increase in γδ T cell numbers in PU.1 deficient mice is reflected in several subsets examined (Vγ2T, Vγ3T and Vδ4T). In mice where PU.1 was deleted using a CD4-Cre transgene, the expansion of γδ T cell numbers was restricted to the intestinal population. PU.1-deficient γδ T cells secrete higher levels of IL-17 than wild type cells, but similar levels of IFN-γ. Thus, our data show that PU.1 is expressed in γδ T cells and that deletion of PU.1 results in γδ T cell expansion. This suggests that PU.1 has a negative influence on γδ T cell development or expansion.

Teratogenic effects of lead acetate on kidney

BACKGROUND

Lead remains a considerable occupational and public health problem, which is known to cause a number of adverse effects in both men and women. Conflicting reports have appeared on lead induced nephrotoxicity in experimental studies in the past. There is hardly any work on its teratogenic effects on kidney. Present study was therefore designed to investigate the effects of lead acetate on developing kidney.

METHODS

Twelve mice were used as experimental model and were divided into two groups of six animals each; group A served as control group and B was used as an experimental group. Lead acetate (10 mg/kg) dissolved in 0.02 ml of distilled water was administered as a single daily dose orally to group B whereas weight related amount of distilled water was given to group A for the entire period of experiment. On 18th day of gestation foetuses were dissected free of uterine wall under the dissecting microscope and were sacrificed; kidneys were removed and fixed in 10% formalin, dehydrated in ascending grades of alcohol, cleared in xylene and infiltrated with filtered paraffin. The paraffin blocks were made and five micron thin sections were obtained using a rotary microtome. The sections were stained with Hematoxylin and eosin and, PAS; these were examined under light microscope.

RESULTS

Significant decrease in cortical thickness was observed which varied from 578.61 +/- 1.4 microm in group A to 515.6 +/- 5 microm in group B (p < 0.001). Diameter of renal corpuscles varied from 57.7 +/- 0.07 microm in group A to 50.5 +/- 0.07 microm in group B (p < 0.001). Moderate cortical tubular atrophy showing thickening of endothelial basement membrane in glomeruli, desquamated epithelium with degenerated nuclei in proximal and distal tubules were observed in group B in contrast to group A.

CONCLUSION

The results of the investigation indicated that lead acetate administration to the dams produced deleterious effects on the developing kidney in mice.

PU.1 regulates TCR expression by modulating GATA-3 activity

The Ets transcription factor PU.1 is a master regulator for the development of multiple lineages during hematopoiesis. The expression pattern of PU.1 is dynamically regulated during early T lineage development in the thymus. We previously revealed that PU.1 delineates heterogeneity of effector Th2 populations. In this study, we further define the function of PU.1 on the Th2 phenotype using mice that specifically lack PU.1 in T cells using an lck-Cre transgene with a conditional Sfpi1 allele (Sfpi1(lck-/-)). Although deletion of PU.1 by the lck-Cre transgene does not affect T cell development, Sfpi1(lck-/-) T cells have a lower activation threshold than wild-type T cells. When TCR engagement is limiting, Sfpi1(lck-/-) T cells cultured in Th2 polarizing conditions secrete higher levels of Th2 cytokines and have greater cytokine homogeneity than wild-type cells. We show that PU.1 modulates the levels of TCR expression in CD4(+) T cells by regulating the DNA-binding activity of GATA-3 and limiting GATA-3 regulation of TCR gene expression. GATA-3-dependent regulation of TCR expression is also observed in Th1 and Th2 cells. In CD4(+) T cells, PU.1 expression segregates into subpopulations of cells that have lower levels of surface TCR, suggesting that PU.1 contributes to the heterogeneity of TCR expression. Thus, we have identified a mechanism whereby increased GATA-3 function in the absence of the antagonizing activity of PU.1 leads to increased TCR expression, a reduced activation threshold, and increased homogeneity in Th2 populations.

Prophylactic Role of Immunomodulators in Treatment of Systemic Candidiasis in Leukopenic Mice

In the present study, we have evaluated prophylactic role of various immunomodulators viz. lipopolysachharide, protein A and tuftsin to impart protection against experimental candidiasis in leukopenic mice. Both free as well as liposomised form of nystatin was not effective enough in offering complete cure against less susceptible isolate of Candida albicans (JNMCR) infection in immunodebilitant mice. Interestingly, the pretreatment of leukopenic mice with immunomodulators before challenging them with C. albicans increased therapeutic efficacy of the nystatin against systemic candidiasis. Efficacy of the treatment was evaluated on the basis of survival of the animals as well as fungal load in systemic circulation and various organs viz. liver, kidney, spleen and lungs of the treated animals.

Inactivation and modification of superoxide dismutase by glyoxal: Prevention by antibodies

Glyoxal is an endogenous compound, the levels of which are increased in various pathologies associated with hyperglycaemia and other related disorders. It has been reported to inactivate critical cellular enzymes by promoting their cross-linking and perpetuates advanced glycation end-product (AGE) formation. In this study, we used superoxide dismutase (SOD) as a model to investigate the ability of specific anti-enzyme antibodies and monomer Fab fragments to protect against glyoxal-induced deactivation and aggregate formation. We found that glyoxal deactivated SOD, in a concentration and time-dependent fashion. The enzymatic activity was monitored spectrophotometrically and it was found that enzyme lost approximately 95% of its original activity, when exposed to 10 mM glyoxal for 120 h. SDS-polyacrylamide gel electrophoresis demonstrated the formation of high molecular weight aggregates in SOD samples exposed to glyoxal. Surface-enhanced laser desorption/ionization time of flight mass spectrometry (SELDI-TOF-MS) showed increase in relative molecular mass (M(r)), upon exposure to glyoxal. Specific anti-enzyme antibodies and monomer Fab fragments markedly inhibited SOD deactivation caused by glyoxal and decreased the extent of cross-linking or formation of aggregates. This protection by the antibodies or Fab fragments was specific since, other non-specific antibodies were not able to protect SOD. Previously, antibodies have been used to prevent aggregation of beta-amyloid peptides in Alzheimer and prion-protein disease. Our findings provide a new perspective, for use of antibodies to prevent the biomolecules against glycation-induced deactivation and alteration.

Capillary electrophoresis and the clinical laboratory

Over the past 15 years, CE as an analytical tool has shown great promise in replacing many conventional clinical laboratory methods, such as electrophoresis and HPLC. CE's appeal was that it was fast, used very small amounts of sample and reagents, was extremely versatile, and was able to separate large and small analytes, whether neutral or charged. Because of this versatility, numerous methods have been developed for analytes that are of clinical interest. Other than molecular diagnostic and forensic laboratories CE has not been able to make a major impact in the United States. In contrast, in Europe and Japan an increasing number of clinical laboratories are using CE. Now that automated multicapillary instruments are commercially available along with cost-effective test kits, CE may yet be accepted as an instrument that will be routinely used in the clinical laboratories. This review will focus on areas where CE has the potential to have the greatest impact on the clinical laboratory. These include analyses of proteins found in serum and urine, hemoglobin (A1c and variants), carbohydrate-deficient transferrin, forensic and therapeutic drug screening, and molecular diagnostics.

Antibodies and Fab fragments protect Cu,Zn-SOD against methylglyoxal-induced inactivation

Methyl glyoxal (MG) is a highly reactive alpha-oxoaldehyde that plays an important role in non-enzymatic glycosylation reactions, formation of Advanced Glycation End products (AGEs) and other complications associated with hyperglycemia and related disorders. Unlike sugars, glycation by MG is predominantly arginine directed, which is particularly more damaging since arginine residues have a high-frequency occurrence in ligand and substrate recognition sites in receptor and enzyme active sites. Using bovine erythrocyte Cu,Zn-superoxide dismutase (SOD) as model enzyme, the potential of anti-enzyme antibodies in imparting protection against MG-induced inactivation was investigated. A concentration- and time-dependent inactivation of SOD was observed when the enzyme was incubated with MG. The enzyme lost over 80% activity on incubation with 5 mM MG for 5 days. More marked inactivation was observed in 24 h when the MG concentration was raised up to 30 mM. The SOD inactivation was accompanied by the formation of high molecular weight aggregates as revealed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and surface enhanced laser desorption/ionization time of flight mass spectrometry (SELDI/TOF mass spectrometry). Inclusion of specific anti-SOD antibodies raised in rabbits or monomeric Fab fragments derived thereof offered remarkable protection against MG-induced loss in enzyme activity. The protection, however, decreased with increase in the concentration of MG. SELDI/TOF mass spectrometry also revealed that the antibodies restricted the formation of high molecular weight aggregates. The results emphasize the potential of antibody based therapy in combating glycation and related complications.

Polyclonal antibodies inhibit the glycation-induced inactivation of bovine Cu,Zn-superoxide dismutase

In vitro incubation of bovine Cu,Zn-SOD (Cu,Zn-superoxide dismutase) with glucose, ribose or fructose results in a remarkable inactivation of the enzyme. There was a progressive decrease in enzyme activity on incubation with glucose and, at the end of 7 days, only 26% of the initial activity remained. The inactivation was accompanied by a parallel decrease in the amount of protein detectable on gels after SDS/PAGE. Reaction of the sugars with SOD was ascertained using an immunoblot assay in which sugar-incubated SOD was derivatized with 2,4-dinitrophenylhydrazine and allowed to react with the dinitrophenol-specific antibody. Affinity purified antibodies from the sera of rabbits immunized with bovine SOD were highly effective in restricting the inactivation of the enzyme induced by glucose, ribose or fructose.

Analytical evaluation of HgbA1c, microalbumin, CRP, and RF on Architect ci8200 integrated system and workflow performance evaluation using computer simulation

BACKGROUND

Recently, hemoglobin A1c (HgbA1c), microalbumin (MA), C-reactive protein (CRP) and rheumatoid factor (RF) have been introduced on high throughput general chemistry system. We evaluated analytical performance of these assays on an integrated clinical chemistry and immunoassay analyzer and studied the impact of testing these assays on these systems on the overall efficiency of the analyzer, via computer simulation.

METHODS

The analytical performance was measured by determining precision, linearity and correlation of patient sample results with in-house testing methodology. MedModel simulation software is used to develop simulation model and process efficiency is determined by measuring turnaround times and resource utilization.

RESULTS

Between-days CVs ranged from 8.59% for MA to 3.22% for HgbA1c level 1 controls. Less than 2% carryover for all 4 methods was observed on the integrated analyzer. For HgbA1c on HPLC analyzer, the minimum and maximum TAT for a batch of 50 samples was 3.78 and 160 min, respectively, while for the integrated system it was 28.2 and 35.1 min, respectively. Labor utilization for the 2 processes ranged from 3.21% to 3.75%.

CONCLUSION

Chemistry module on an integrated system can be used to determine the HgbA1c and other serum proteins.

Prophylactic role of liposomized chloroquine against murine cryptococcosis less susceptible to fluconazole

PURPOSE

The prophylactic role of liposomized chloroquine (lip-CQ) has been assessed against less susceptible Cryptococcus neoformans infection in murine model.

METHODS

In the current study, we investigated the antifungal activity of lip-CQ against C. neoformans in macrophages cell line (J 774) and murine model. Mice were pretreated with free as well as liposomized formulations of CQ at various doses. The anticryptococcal activity of fluconazole was compared in mice with or without CQ pretreatment. The efficacy of CQ prophylaxis was assessed by survival as well as colony forming units (cfu) in brain and lungs of treated mice.

RESULTS

Fluconazole alone was not found significantly effective against C. neoformans in both in vitro and in vivo studies. However, the antifungal activity of fluconazole increases in chloroquine-pretreated mice. Lip-CQ was found to be more effective in comparison to the same dose of free chloroquine in reducing fungal burden from macrophages in vitro and lungs and brain of C. neoformans infected mice.

CONCLUSIONS

The enhanced prophylactic activity of lip-CQ seems due to rapid uptake of drug-containing liposomes by macrophages. The liposome-mediated accumulation of CQ in macrophages makes the environment unfavorable (alkaline) for the intracellular multiplication of C. neoformans. Moreover, the increased incidence of multi-drug resistance and diversity of pathogenic microorganisms inhibited or killed by CQ makes it the drug of choice for prophylactic therapy.

Enhanced anticryptococcal activity of chloroquine in phosphatidylserine-containing liposomes in a murine model

OBJECTIVES

The anticryptococcal activity of chloroquine was assessed after incorporation in phosphatidylserine (PS)-containing negatively charged liposomes in a murine model.

METHODS

In the present study, we investigated the antifungal activity of chloroquine entrapped in PS liposomes against Cryptococcus neoformans in the macrophage cell line J 774 and in a murine model. Mice were treated with free as well as liposomal formulations of chloroquine before and after challenging with C. neoformans infection. The anticryptococcal activity of chloroquine was also evaluated in combination with fluconazole in the treatment of systemic murine cryptococcosis. The efficacy of chloroquine treatment was assessed by continued survival as well as by colony forming units (cfu) in liver and brain of treated mice.

RESULTS

Chloroquine entrapped in PS liposomes shows increased activity against C. neoformans infection both in in vitro and in vivo studies. Moreover, the antifungal activity of fluconazole increases when used in combination with liposomal chloroquine. Chloroquine in PS liposomes was found to be more effective in comparison with the same dose of free chloroquine or chloroquine entrapped in neutral liposomes.

CONCLUSIONS

The enhanced anticryptococcal activity of chloroquine in PS liposomes seems to be due to uptake of drug-containing PS liposomes by macrophages. It can be assumed that liposome-mediated delivery of chloroquine to macrophages results in an unfavourable (alkaline) environment for the growth of C. neoformans inside macrophages.

Egrets as monitors of trace-metal contamination in wetlands of Pakistan

Environments in Pakistan are subject to increasing pollution, but previous studies were very scanty. During 1999 and 2000, we assessed trace element contamination at three wetlands, Karachi Harbour (with presumed industrial-urban pollution), Taunsa Barrage (agricultural pollution), and Haleji Lake (relatively unpolluted), using as indicators the eggs and the feathers of colonial waterbirds, particularly Little Egrets, their prey, and the sediments collected within their foraging areas. The concentrations of As, Cd, Cr, Pb, Hg, Mn, Se, and Zn were generally within the normal background level, and mostly below the threshold that may affect bird survival or reproduction. However, somewhat high concentrations were found in fish from Karachi, for Pb that was at levels that may harm fish reproduction, and for Hg that was at limit concentration for human consumption. Alarming concentrations were found for Cr and Se in sediments from Karachi, that were above the critical levels for contaminated soil, and Se in eggs, that may affect egret reproduction. The differences among the three wetlands were less marked than hypothesized. The egret species within the same area differed in the concentration of certain elements in their eggs, possibly because females may have foraged in different habitats before breeding, whereas no interspecies difference was found in chick feathers, presumably because their food had been collected in similar habitats around the colony. High bioaccumulation from sediments to organic samples occurred for Hg, while Cd, Se, and Zn exhibited low accumulation; for all these elements, feathers of predatory birds such as the egrets are the best indicators of environmental contamination. On the other hand, As and Cr did not bioaccumulate, and the sediments, or the organisms low in the food chain, like fish or crustaceans, are better indicators of their presence in the environment than predatory birds.

Persistent organic pollutants in little egret eggs from selected wetlands in Pakistan

The main goal of the present work has been to study the use of egret eggs to assess environmental pollution by POPs (HCB, HCHs, cyclodienes, DDTs and PCBs) in three Pakistani wetlands that are presumed to be affected by different types of pollution. Taunsa Barrage, affected mainly by agricultural pollutants; Karachi Harbor because of the supposed exposure to industrial activity-related POPs; and Haleji Lake as a relatively pristine area because of its location in a stony desert. Taunsa Barrage and Haleji Lake are wetlands of international importance according to the Ramsar Convention, while the Karachi Harbor is of interest because of the large human population living there. Eggs of the white ( Egretta garzetta garzetta) and dark ( Egretta garzetta gularis) morphs of Little Egrets were used as monitoring tools. Concentrations were also determined in several prey in this species' diet and in the sediments collected in their foraging areas. Differences in egg pollutant content among the three localities were significant for all the compounds. Overall, the eggs from Haleji Lake and Karachi showed, respectively, the lowest and highest percentages of detection and organochlorine concentrations. Biomagnification from sediments to prey and then to eggs has been documented in the three areas studied and is accompanied by higher percentages of detection of different compounds through the compartments. Differences in the biomagnification factor among the areas were small, even when differences in pollutant concentrations were high, suggesting that eggs are reliable indicators of POPs in the environment. The values found were generally lower than those reported for the eggs of large herons from North America or the Mediterranean basin, and are about the same order of magnitude that those of other medium-sized egrets from other parts of the world.

Role of dexamethasone in acute bacterial meningitis in adults

OBJECTIVE

To evaluate the role of dexamethasone as adjunctive therapy in adult acute bacterial meningitis (ABM) in two groups of patients treated with antibiotics alone or a combination of antibiotics and dexamethasone.

DESIGN

Systematic sampling interventional open cohort study.

SETTING

Department of Medicine (Medical Unit II), Jinnah Postgraduate Medical Centre, Karachi.

PATIENTS

Sixty eight patients aged 12-85 years admitted in Medical Unit II and diagnosed to have ABM. Patients were divided into two groups. Group A received anti-microbial therapy for 14 days (a combination of benzyl penicillin 6 million units I/V 6 hourly and chloramphenicol 1 gm I/V 6 hourly) and group B received the same antimicrobial therapy with dexamethasone 0.6 mg/kg/day in 3 divided doses for 4 days.

MAIN OUTCOME MEASURES

Differences in mortality and morbidity in the two groups and differences in the CSF inflammatory parameters between the two groups of patients.

RESULTS

There was early resolution of fever, headache and altered consciousness in group B as compared to group A. Cranial nerves involvement was lower in group B. There was no difference in the occurrence of other focal neurological deficits between the two groups. CSF inflammatory parameters (glucose, protein and WBC count) were significantly better in group B by day 5. No complications attributable to dexamethasone were seen in group B.

CONCLUSION

There was early resolution of symptoms and CSF inflammatory parameters in the group that received dexamethasone as adjuvant therapy. Mortality was lower in the group treated with dexamethasone but the difference was not statistically significant. Dexamethasone should be administered to all adults patients with ABM.