Abatacept increases T cell exhaustion in early RA individuals who carry HLA risk alleles

Exhausted CD8 T cells (TEX) are associated with worse outcome in cancer yet better outcome in autoimmunity. Building on our past findings of increased TIGIT+KLRG1+ TEX with teplizumab therapy in type 1 diabetes (T1D), in the absence of treatment we found that the frequency of TIGIT+KLRG1+ TEX is stable within an individual but differs across individuals in both T1D and healthy control (HC) cohorts. This TIGIT+KLRG1+ CD8 TEX population shares an exhaustion-associated EOMES gene signature in HC, T1D, rheumatoid arthritis (RA), and cancer subjects, expresses multiple inhibitory receptors, and is hyporesponsive in vitro, together suggesting co-expression of TIGIT and KLRG1 may broadly define human peripheral exhausted cells. In HC and RA subjects, lower levels of EOMES transcriptional modules and frequency of TIGIT+KLRG1+ TEX were associated with RA HLA risk alleles (DR0401, 0404, 0405, 0408, 1001) even when considering disease status and cytomegalovirus (CMV) seropositivity. Moreover, the frequency of TIGIT+KLRG1+ TEX was significantly increased in RA HLA risk but not non-risk subjects treated with abatacept (CTLA4Ig). The DR4 association and selective modulation with abatacept suggests that therapeutic modulation of TEX may be more effective in DR4 subjects and TEX may be indirectly influenced by cellular interactions that are blocked by abatacept.

CD8 T cell exhaustion is reduced in subjects with autoimmune-associated DR4 risk alleles

Exhausted CD8 T cells (TEX) are associated with worse outcome in cancer and better outcome in autoimmunity. However, factors contributing to reduced TEX in the context of autoimmunity are not well understood. Here, we identify co-expression of TIGIT and KLRG1 as a broad identifier of human TEX: TIGIT+KLRG1+ CD8 memory T cells share EOMES signature genes in healthy controls (HC), T1D and Rheumatoid Arthritis (RA) subjects, are increased with age and in chronic viral-specific cells, and are hyporesponsive (reduced proliferation and cytokine production) in vitro. We applied this inclusive, sample sparing and high throughput measure of TEX to larger longitudinal and autoimmune cohorts. Consistent with a genetic determinant, TEX are stable within HC and T1D individuals (Interclass correlation coefficient=92.0 and 83.7%, respectively), but display high interindividual variation (range 0.37–28.47 of CD8). In a large cohort of HC and RA subjects (n>100/cohort), lower levels of EOMES modules and TEX were associated with the HLA Class II DR4 autoimmune risk allele, regardless of disease status. While the DR4 locus is complex, these findings suggest that TEX may be indirectly influenced by APC or CD4 T cell help. Moreover, therapeutic modulation of TEX may differ in DR4 risk and non risk subjects, with implications for precision medicine.

Supported by grants from the NIH (R01 AI141952, R21 5R21AR073508-02) and JDRF.

Cows as Bioreactors for the Production of Nutritionally and Biomedically Significant Proteins

Dairy and beef cattle make a vital contribution to global nutrition, and since their domestication, they have been continuously exposed to natural and artificial selection to improve production characteristics. The technologies of transgenesis and gene editing used in cattle are responsible for generating news characteristics in bovine breeding, such as alteration of nutritional components of milk and meat enhancing human health benefits, disease resistance decreasing production costs and offering safe products for human food, as well as the recombinant protein production of biomedical significance. Different methodologies have been used to generate transgenic cattle as bioreactors. These methods include the microinjection of vectors in pronuclear, oocyte or zygote, sperm-mediate transgenesis, and somatic cell nuclear transfer. Gene editing has been applied to eliminate unwanted genes related to human and animal health, such as allergy, infection, or disease, and to insert transgenes into specific sites in the host genome. Methodologies for the generation of genetically modified cattle are laborious and not very efficient. However, in the last 30 years, transgenic animals were produced using many biotechnological tools. The result of these modifications includes (1) the change of nutritional components, including proteins, amino acids and lipids for human nutrition; (2) the removal allergic proteins milk; (3) the production of cows resistant to disease; or (4) the production of essential proteins used in biomedicine (biomedical proteins) in milk and blood plasma. The genetic modification of cattle is a powerful tool for biotechnology. It allows for the generation of new or modified products and functionality that are not currently available in this species.

The many faces of islet antigen-specific CD8 T cells: clues to clinical outcome in type 1 diabetes

Immune monitoring enables a better understanding of disease processes and response to therapy, but has been challenging in the setting of chronic autoimmunity because of unknown etiology, variable and protracted kinetics of the disease process, heterogeneity across patients and the complexity of immune interactions. To begin to parse this complexity, we focus here on type 1 diabetes (T1D) and CD8 T cells as a cell type that has features that are associated with different stages of disease, rates of progression and response to therapy. Specifically, we discuss the current understanding of the role of autoreactive CD8 T cells in disease outcome, which implicates particular CD8 functional subsets, rather than unique antigens or total number of autoreactive T cells. Next, we discuss how autoreactive CD8 T‐cell features can be reflected in measures of global CD8 T cells, and then pull these concepts together by highlighting immune therapies recently shown to modulate both CD8 T cells and disease progression. We end by discussing outstanding questions about the role of specific subsets of autoreactive CD8 T cells in disease progression and how they may be optimally modulated to treat and prevent T1D.

Australian action to reduce health risks from radon

In Australia, worker exposure to radon in underground uranium mines has been a focus of policy makers and regulators, and has been well controlled in the industry sector. That cannot be said for public exposure to radon. Radon exposure studies in the late 1980s and early 1990s demonstrated that the levels of radon in Australian homes were some of the lowest in the world. The International Basic Safety Standards, published by the International Atomic Energy Agency, requires the government to establish and implement an action plan for controlling public exposure due to radon indoors. When considering different policy options, it is important to develop radon prevention and mitigation programmes reflecting elements that are unique to the region or country. The Australian Radon Action Plan is being considered at a national level, and presents a long-range strategy designed to reduce radon-induced lung cancer in Australia, as well as the individual risk for people living with high concentrations of radon. In Australia, workers who are not currently designated as occupationally exposed are also considered as members of the public. In the Australian context, there are only a limited set of scenarios that might give rise to sufficiently high radon concentrations that warrant mitigation. These include highly energy efficient buildings in areas of high radon potential, underground workplaces, workplaces with elevated radon concentrations (e.g. spas using natural spring waters), and enclosed workspaces with limited ventilation. The key elements for a successful plan will rely on collaboration between government sectors and other health promotion programmes, cooperative efforts involving technical and communication experts, and partnering with building professionals and other stakeholders involved in the implementation of radon prevention and mitigation.

Natural Killer Cell Re-Modeling of the Extra-Cellular Matrix by the Degradation of Hyaluronan: Potential Role in Type 1 Diabetes

Natural Killer (NK) cells have been shown to contribute to early insulitis during development of Type 1 Diabetes (T1D). We previously identified increased Hyaluronan (HA) deposition within inflamed pancreatic islets, indicative of remodeling of the extra cellular matrix (ECM) of which HA is a component. NK cells express CD44, a ligand for HA, and granzymes known to facilitate extravasation through the ECM. Thus, we asked whether NK cells may directly interact with the ECM, potentially contributing to HA modification in pancreatic islets. Isolated NK cells activated with IL-12, IL-15, and IL-18 up-regulated Has3, CD44, and Hyal1: genes related ECM re-modeling suggesting that NK cells may act upon the ECM. To test NK-ECM interactions, we used a co-culture system of stimulated NK cells and HA producing fibroblasts. We found down-regulation of Hyaluronidases Hyal1 and Hyal2 and up-regulation of HA Synthases Has1 and Has2. These results are consistent with NK cell modulation of ECM, that was also indicated by depletion of the fibroblast cell layer. Comparatively, CD4 and CD8 T cells did not show depletion of the cell layer and differed in the degree and composition of ECM related transcripts. Together, these data suggest that NK cells play a critical role in ECM re-modeling; this NK-ECM interaction may contribute to pancreatic inflammation in the setting of T1D.

Extensive characterization of islet-reactive CD8 T cells in type 1 diabetes by mass cytometry (CyTOF)

In type 1 diabetes (T1D), insulin-secreting beta cells of the pancreatic islets are targets of autoimmune destruction by T lymphocytes, resulting in insulin deficiency and dysregulation of glucose metabolism. CD8 T cells reactive to islet antigens have been implicated in this process, and phenotypic changes in CD8 T cells have been observed in the transition to clinical diabetes. While efforts have led to identification of peptide antigens targeted by autoreactive CD8 T cells, less has been done to characterize the phenotype and function of this population. We developed a 25+ marker mass cytometry (CyTOF) panel to identify and extensively characterize CD8 T cells reactive to pooled class I (HLA-A2) tetramer loaded with peptides of viral or islet antigens in the same sample. Results were confirmed with several smaller flow panels. In PBMCs of three healthy controls and four T1D patients, we found virus-specific CD8 T cells had a more memory- and exhausted-like phenotype compared to total CD8 T cells, including increased T effector memory (CD45RO+CCR7−), KLRG1, CD57, TIGIT, and PD1, and decreased naïve T cells (CD45RO−CCR7+). In contrast, islet-specific CD8 T cells (detectable in three T1D patients) did not vary significantly from total CD8 T cells. Given the differences in phenotype between viral and total CD8 T cells, we successfully used unsupervised clustering analysis software to reveal a distinct virus-specific CD8 T cell population. This approach of using pooled tetramer for detection of total viral and autoreactive CD8 T cells in the same sample, in combination with extensive phenotyping by mass cytometry will be useful in monitoring important phenotypic changes in this population during disease progression and in response to therapy.

Immune regulatory receptors expressed on NK cells in type 1 diabetes

Auto-reactive T cells specific to islet antigens contribute to the onset of type 1 diabetes (T1D), yet NK cells may also play a role in disease onset and progression. Mouse models suggest a dual role for NK cells in disease onset and progression while human studies have found deficiencies in NK number and function. However, human studies are confounded by variability in cohorts (pre-T1D, recent onset, long-standing T1D) and more phenotypic and functional analysis as has been performed in murine studies. In our initial studies, we characterized activation and inhibitory markers on NK cells of longstanding T1D (n=5) as compared to healthy controls (n=6). NK cells from the same sample were then compared to known T cell phenotypes. PBMC were analyzed by flow cytometry for markers of T and NK cells (CD45RA, CCR7, CD56, CD4 and CD8), immune regulation (PD1, KLRG1, TIGIT and CD57) and activation (CD69 and CD25). Results showed that there was a significant elevation of T cells but a decrease of NK subsets (CD56dim and bright) in T1D compared to healthy controls. Both CD57+ and CD57+TIGIT+ NK cells were significantly reduced in T1D, implying a more immature and less regulatory phenotype or more activated phenotype. In the same subjects, both CD4 and CD8 memory T cell populations expressing PD1 were significantly lower in T1D than in healthy controls. Moreover, the CD8 EMRA (CCR7− CD45RA+) T cells exhibited decreased KLRG1, TIGIT and CD57 expression. Taken together, these findings revealed a skewing of NK cell subsets in T1D. Further functional characterization of both NK and T cells in the same sample may lead to identification of biomarkers for T1D.

Association of common polymorphisms in the IL2RA gene with type 1 diabetes: evidence of 32,646 individuals from 10 independent studies

Single nucleotide polymorphisms (SNPs) in the interleukin 2 receptor alpha (IL2RA) gene have been suggested to be associated with type 1 diabetes (T1D) susceptibility. However, the results from individual studies are inconsistent. To explore the association of IL2RA polymorphisms with T1D, including rs11594656, rs2104286, rs3118470, rs41295061 and rs706778, a meta-analysis involving 10 independent studies with 19 outcomes was conducted: five studies with a total of 10,572 cases and 12,956 controls were analysed for rs11594656 with T1D risk, three studies with 7300 cases and 8331 controls for rs2104286, three studies with 3880 cases and 5409 controls for rs3118470, five studies with 11,253 cases and 13,834 controls for rs41295061 and three studies with 1896 cases and 1709 controls for rs706778 respectively. Using minor allelic comparison, the five investigated SNPs were all observed to have a significant association with T1D: For rs11594656, fixed effect model (FEM) odds ratio (OR) 0.87, 95% confidence interval (CI) 0.83, 0.91; rs2104286, FEM OR 0.81, 95% CI 0.77, 0.85; rs3118470, FEM OR 1.23, 95% CI 1.16, 1.31; rs41295061, random effect model (REM) OR 0.67, 95% CI 0.60, 0.76 and rs706778 FEM OR 1.20, 95% CI 1.08, 1.33. Similar results were obtained when all the included studies were calculated by a REM. Our meta-analysis suggests that all five SNPs in the IL2RA gene are risk factors for T1D risk, and rs11594656, rs2104286 and rs41295061 are the most associated SNPs in the populations investigated. This conclusion warrants confirmation by further studies.

Invasion of Wolbachia at the residential block level is associated with local abundance of Stegomyia aegypti, yellow fever mosquito, populations and property attributes

Wolbachia can suppress dengue and control mosquito populations and this depends on the successful invasion of Wolbachia-infected mosquitoes into local populations. Ovitrap data collected during the recent invasion of wMel-infected Stegomyia aegypti (Diptera: Culicidae) (Linnaeus) into Gordonvale near Cairns, Australia, were used to identify variables that help predict the success of localized invasion. Based on the variance in Wolbachia frequencies across Gordonvale as well as at another release site at Yorkeys Knob in comparison to simulations, it was estimated that on average 2-4 females contributed eggs to an ovitrap. By collating ovitrap data from two collection periods at the start of the release from residential blocks, it was found that uninfected mosquitoes had a patchy distribution across the release site. Residential blocks with relatively high uninfected mosquito numbers were less easily invaded by Wolbachia than blocks with low numbers. The numbers of uninfected mosquitoes in ovitraps were negatively correlated with the proportion of brick houses in a residential block, whereas local Wolbachia frequencies were correlated positively with this variable as well as negatively with the amount of shading in a yard and availability of breeding sites. These findings point to proxy measures for predicting the ease of localized invasion of Wolbachia.

In active relapsing-remitting multiple sclerosis, effector T cell resistance to adaptive T(regs) involves IL-6-mediated signaling

Patients with multiple sclerosis (MS) manifest demyelination and neurodegeneration mediated in part by CD4(+) T cells that have escaped regulation. Resistance of pathogenic effector T cells (T(effs)) to suppression by regulatory T cells (T(regs)) has been demonstrated in several autoimmune diseases. Although impairment in T(reg) number and function has been observed in relapsing-remitting MS (RRMS), T(eff) resistance has not been well studied in this disease. To determine whether T(eff) resistance contributes to failed tolerance in RRMS, we performed T(reg) suppression assays with T(effs) from either RRMS patients not on immunomodulatory therapy or healthy individuals. T(eff) resistance was present in the T(effs) of RRMS patients with active disease but not from patients with inactive disease. Interleukin-6 (IL-6) and phosphorylation of signal transducer and activator of transcription 3 (pSTAT3) promote T(eff) resistance to T(regs), and we found an increase in IL-6 receptor α (IL-6Rα) expression and elevated IL-6 signaling as measured by pSTAT3 in our RRMS subjects. Further, the impaired suppression in RRMS subjects correlated with an increase in IL-6Rα surface expression on CD4(+) T cells and an increase in pSTAT3 in response to IL-6. To address whether the enhanced pSTAT3 contributed to T(eff) resistance in active RRMS patients, we blocked STAT3 phosphorylation and found that impaired suppression was reversed. Therefore, enhanced IL-6R signaling through pSTAT3, in some cases through increased IL-6Rα expression, contributed to T(eff) resistance in active RRMS. These markers may aid in determining disease activity and responsiveness to immunomodulatory therapies in RRMS.

Evaluation of in vivo T cell kinetics: use of heavy isotope labelling in type 1 diabetes

CD4(+) memory cell development is dependent upon T cell receptor (TCR) signal strength, antigen dose and the cytokine milieu, all of which are altered in type 1 diabetes (T1D). We hypothesized that CD4(+) T cell turnover would be greater in type 1 diabetes subjects compared to controls. In vitro studies of T cell function are unable to evaluate dynamic aspects of immune cell homoeostasis. Therefore, we used deuterium oxide ((2) H(2)O) to assess in vivo turnover of CD4(+) T cell subsets in T1D (n = 10) and control subjects (n = 10). Serial samples of naive, memory and regulatory (T(reg)) CD4(+) T cell subsets were collected and enrichment of deoxyribose was determined by gas chromatography-mass spectrometry (GC-MS). Quantification of T cell turnover was performed using mathematical models to estimate fractional enrichment (f, n = 20), turnover rate (k, n = 20), proliferation (p, n = 10) and disappearance (d*, n = 10). Although turnover of T(regs) was greater than memory and naive cells in both controls and T1D subjects, no differences were seen between T1D and controls in T(reg) or naive kinetics. However, turnover of CD4(+) memory T cells was faster in those with T1D compared to control subjects. Measurement and modelling of incorporated deuterium is useful for evaluating the in vivo kinetics of immune cells in T1D and could be incorporated into studies of the natural history of disease or clinical trials designed to alter the disease course. The enhanced CD4(+) memory T cell turnover in T1D may be important in understanding the pathophysiology and potential treatments of autoimmune diabetes.

An autoimmune-associated variant in PTPN2 reveals an impairment of IL-2R signaling in CD4(+) T cells

The IL-2/IL-2R signaling pathway has an important role in autoimmunity. Several genes identified in genome-wide association (GWA) studies encode proteins in the IL-2/IL-2R signaling cascade that are associated with autoimmune diseases. One of these, PTPN2, encodes a protein tyrosine phosphatase that is highly expressed in T cells and regulates cytokine signaling. An intronic risk allele in PTPN2, rs1893217(C), correlated with decreased IL-2R signaling in CD4(+) T cells as measured by phosphorylation of STAT5 (phosphorylated STAT5 (pSTAT5)). We modeled an additive single nucleotide polymorphism (SNP) genotype, in which each copy of the risk allele conferred a decrease in IL-2R signaling (P=4.4 × 10(-8)). Decreased pSTAT5 impacted IL-2Rβ chain signaling resulting in reduced FOXP3 expression in activated cells. This phenotype was not due to overt differences in expression of the IL-2R, molecules in the IL-2R signaling cascade or defects in STAT5. However, the rs1893217(C) risk variant did correlate with decreased PTPN2 expression in CD4(+)CD45RO T cells (P=0.0002). Thus, the PTPN2rs1893217(C) risk allele associated with reduced pSTAT5 in response to IL-2 and reduced PTPN2 expression. Together, these data suggest that decreased expression of PTPN2 may indirectly modulate IL-2 responsiveness. These findings, identified through genotype/phenotype relationships, may lead to identification of novel mechanisms underlying dysregulation of cytokine signaling in autoimmunity.

A lethal ovitrap-based mass trapping scheme for dengue control in Australia: II. Impact on populations of the mosquito Aedes aegypti

In Cairns, Australia, the impacts on Aedes aegypti L. (Diptera: Culicidae) populations of two types of 'lure & kill' (L&K) lethal ovitraps (LOs), the standard lethal ovitrap (SLO) and the biodegradable lethal ovitrap (BLO) were measured during three mass-trapping interventions. To assess the efficacy of the SLO, two interventions (one dry season and one wet season) were conducted in three discrete areas, each lasting 4 weeks, with the following treatments: (i) SLOs (>200 traps, approximately 4/premise), BG-sentinel traps (BGSs; approximately 15, 1/premise) and larval control (container reduction and methoprene treatment) and (ii) larval control alone, and (iii) untreated control. Female Ae. aegypti populations were monitored for 4 weeks pre- and post-treatment in all three areas using BGSs and sticky ovitraps (SOs) or non-lethal regular ovitraps (ROs). In the dry season, 206 SLOs and 15 BGSs set at 54 and 15 houses, respectively, caught and killed an estimated 419 and 73 female Ae. aegypti, respectively. No significant decrease in collection size of female Ae. aegypti could be attributed to the treatments. In the wet season, 243 SLOs and 15 BGSs killed approximately 993 and 119 female Ae. aegypti, respectively. The mean number of female Ae. aegypti collected after 4 weeks with SOs and BGSs was significantly less than the control (LSD post-hoc test). The third mass-trapping intervention was conducted using the BLO during the wet season in Cairns. For this trial, three treatment areas were each provided with BLOs (>500, approximately 4/premise) plus larval control, and an untreated control area was designated. Adult female Ae. aegypti were collected for 4 weeks pre- and post-treatment using 15 BGSs and 20 SOs. During this period, 53.2% of BLOs contained a total of 6654 Ae. aegypti eggs. Over the intervention period, collections of Ae. aegypti in the treatment areas were significantly less than in the control area for BGSs but not SOs. An influx of relatively large numbers of young females may have confounded the measurement of changes in populations of older females in these studies. This is an important issue, with implications for assessing delayed action control measures, such as LOs and parasites/pathogens that aim to change mosquito age structure. Finally, the high public acceptability of SLOs and BLOs, coupled with significant impacts on female Ae. aegypti populations in two of the three interventions reported here, suggest that mass trapping with SLOs and BLOs can be an effective component of a dengue control strategy.

A lethal ovitrap-based mass trapping scheme for dengue control in Australia: I. Public acceptability and performance of lethal ovitraps

We report on the first field evaluation of the public acceptability and performance of two types of lethal ovitrap (LO) in three separate trials in Cairns, Australia. Health workers were able to set standard lethal ovitraps (SLOs) in 75 and 71% of premise yards in the wet and dry season, respectively, and biodegradable lethal ovitraps (BLOs) in 93% of yards. Public acceptance, measured as retention of traps by residents, was high for both trap types, with <9% of traps missing after 4 weeks. Traps retaining water after 4 weeks were 78 and 34% for the two SLO trials and 58% for the BLOs. The 'failure rate' in the 535 BLOs set in the field for 4 weeks was 47%, of which 19% were lost, 51% had holes from probable insect chewing, 23% were knocked over, 7% had dried by evaporation and 1% were split. There was no significant difference in the failure rate of BLOs set on porous (grass, soil and mulch) versus solid (tiles, concrete, wood and stone) substrates. The SLOs and the BLOs were readily acceptable to ovipositing Aedes aegypti L. (Diptera: Culicidae); the mean number of eggs/trap was 6 and 15, for the dry season and wet season SLO trial, respectively, and 15 for the BLO wet season trial. Indeed, 84-94% of premise yards had egg positive SLOs or BLOs. A high percentage of both wet and dry season SLOs (29 and 70%, respectively) and BLOs (62%) that were dry after 4 weeks were egg positive, indicating the traps had functioned. Lethal strips from SLOs and BLOs that had been exposed for 4 weeks killed 83 and 74%, respectively, of gravid Ae. aegypti in laboratory assays. These results indicate that mass trapping schemes using SLOs and BLOs are not rejected by the public and effectively target gravid Ae. aegypti. The impact of the interventions on mosquito populations is described in a companion paper.

Persistence of FOXP3 expression is impaired in RR-MS Tregs (99.3)

Impaired Treg function may contribute to the development of Multiple Sclerosis (MS). FOXP3 is required for Treg function and its expression is maintained by the common γ-chain cytokines through phosphorylation of STAT5 (pSTAT5). We examined the pSTAT5 levels of CD4+CD25+Treg from relapsing remitting MS and control subjects in response to low-dose IL-2. We found that, despite equivalent levels of CD25, pSTAT5 was lower in RR-MS subjects (p= 0.0013), indicating a mechanism by which FOXP3 expression and Treg function may be lost in MS. To further examine the expression and persistence of FOXP3 in these subjects we generated adaptive Tregs and followed FOXP3 expression in these cells over time. We found that the initial induction of FOXP3 was similar to that of controls, but by day 10 of culture FOXP3 expression in CD4+CD25+ T cells was significantly lower (p&lt;0.0001). FOXP3 expression could not be rescued by IL-2, IL-7 or IL-2/IL-7 in combination. In addition, cell surface expression of CD122 and CD132 is significantly decreased on RR-MS CD4+ CD25+ T cells. Taken together we conclude that the impaired persistence of FOXP3 expression in aTreg may impact the number and function of Tregs in individuals with RR-MS. This loss of FOXP3 may be due to decreased pSTAT5 in response to IL-2 and IL-7 which may be due to decreased levels of the IL-2R and IL-7R complexes. This work was supported by grants from the JDRF33-2008-398 and DFG108312-1.

Diminished IL-2 responsiveness and FOXP3 expression in T1D subjects is revealed by a disease-associated variant of PTPN2 (49.1)

Impairment in the IL-2/IL-2R pathway results in a loss of regulatory T cells (Treg) and the development of autoimmunity in animal models. Recent genome-wide association studies (GWAS) have identified several genes associated with Type 1 Diabetes (T1D) which may influence IL-2R signaling including the protein tyrosine phosphatase, PTPN2. We demonstrate that CD4+ T cells of healthy subjects that carry the T1D associated variant of PTPN2rs1893217 exhibit impaired signaling in response to IL-2. This is characterized by decreased phosphorylation of STAT5 and diminished FOXP3 expression in response to IL-2. In T1D subjects, a similar defect in IL-2R signaling is seen, however, in T1D subjects this phenotype is present irrespective of PTPN2 genotype. In comparison to controls, the CD4+ T cells of T1D subjects displayed decreased STAT5 phosphorylation upon exposure to IL-2 and IL-15, decreased FOXP3 expression upon activation in the presence of IL-2 and a loss of FOXP3 persistence in nTreg cultured in IL-2. Together these findings indicate that the PTPN2rs1893217 genotype reveals a phenotype common to T1D subjects. This impairment of IL-2 responsiveness may contribute to the development of T1D through diminished number and function of Treg in the inflamed islet.

Optimization of Human T-Cell Expansion Ex Vivo Using Magnetic Beads Conjugated with Anti-CD3 and Anti-CD28 Antibodies

T-cell receptor engagement and accompanying costimulatory signals control the level of activation and functional potential of individual T cells. The authors previously developed a novel technology in which human T cells are activated and expanded in culture ex vivo using anti-CD3 and anti-CD28 monoclonal antibodies covalently linked to superparamagnetic beads (Xcyte Dynabeads). In this study the addition of N-acetyl L-cysteine (NAC) to the cultures markedly increased the expansion of T cells from human peripheral blood mononuclear cells without diminishing cell function. NAC increased the rate of T-cell division, reduced apoptosis, and increased the percentage of antigen-specific memory T cells in the cultures. The effect of varying the ratio of beads to T cells (1:10-10:1) at culture initiation was also evaluated. Polyclonal T cells were expanded at all bead-to-T cell ratios tested (range 1:10-10:1). While high bead-to-T cell ratios (5:1 and 10:1) deleted, low ratios (1:10 and 1:5) preserved memory T cells directed against cytomegalovirus, Epstein-Barr virus, and influenza virus antigens. Adding more anti-CD3/anti-CD28 beads during the culture led to further expansion of T cells. Experiments also revealed that reducing the amount of anti-CD3 antibodies relative to the amount of anti-CD28 antibodies on the beads favored the proliferation of antigen-specific T cells. In summary, these data indicate that T cell-stimulating effects of anti-CD3/anti-CD28 beads can be further manipulated to control the expansion of antigen-specific memory T cells and can be used to rapidly expand antigen-specific T cells ex vivo for potential clinical applications.

Distribution of energy in polymers due to incident electrons and protons

The recoil spectrum of nuclei in polymers for incident protons below 10 MeV in energy is calculated by using the Rutherford cross-section with screening corrections. Employing the work of McKinley and Feshbach on the Coulomb scattering of relativistic electrons by nuclei, the recoil spectrum of the nuclei is also calculated for electron energies varying from threshold to 10 MeV. The partitioning of energy between electronic excitation and ionization and nuclear recoil is then studied to search for possible difference in polymer radiation response as a function of radiation energy and type.

Immunoreactivity of organic mimeotopes of the E2 component of pyruvate dehydrogenase: connecting xenobiotics with primary biliary cirrhosis

In primary biliary cirrhosis (PBC), the major autoepitope recognized by both T and B cells is the inner lipoyl domain of the E2 component of pyruvate dehydrogenase. To address the hypothesis that PBC is induced by xenobiotic exposure, we took advantage of ab initio quantum chemistry and synthesized the inner lipoyl domain of E2 component of pyruvate dehydrogenase, replacing the lipoic acid moiety with synthetic structures designed to mimic a xenobiotically modified lipoyl hapten, and we quantitated the reactivity of these structures with sera from PBC patients. Interestingly, antimitochondrial Abs from all seropositive patients with PBC, but no controls, reacted against 3 of the 18 organic modified autoepitopes significantly better than to the native domain. By structural analysis, the features that correlated with autoantibody binding included synthetic domain peptides with a halide or methyl halide in the meta or para position containing no strong hydrogen bond accepting groups on the phenyl ring of the lysine substituents, and synthetic domain peptides with a relatively low rotation barrier about the linkage bond. Many chemicals including pharmaceuticals and household detergents have the potential to form such halogenated derivatives as metabolites. These data reflect the first time that an organic compound has been shown to serve as a mimeotope for an autoantigen and further provide evidence for a potential mechanism by which environmental organic compounds may cause PBC.

Potent and selective nonpeptide inhibitors of caspases 3 and 7

5-Dialkylaminosulfonylisatins have been identified as potent, nonpeptide inhibitors of caspases 3 and 7. The most active compound within this series (34) inhibited caspases 3 and 7 in the 2-6 nM range and exhibited approximately 1000-fold selectivity for caspases 3 and 7 versus a panel of five other caspases (1, 2, 4, 6, and 8) and was at least 20-fold more selective versus caspase 9. Sequence alignments of the active site residues of the caspases strongly suggest that the basis of this selectivity is due to binding in the S2 subsite comprised of residues Tyr204, Trp206, and Phe256 which are unique to caspases 3 and 7. These compounds inhibit apoptosis in three cell-based models: human Jurkat T cells, human chondrocytes, and mouse bone marrow neutrophils.

Efficacy of an aerosol surface spray against container-breeding Aedes

The effectiveness of a residual insect surface spray against container-breeding mosquitoes was tested in Cairns, Australia. A formulation containing imiprothrin and cypermethrin (Mortein Plus Cockroach Lure 'n' Kill High Performance Surface Spray) was selected based on the label claim to "kill continuously for up to 6 months." A 1-sec spray was applied to the water and interior surface of partially flooded tires and terra-cotta pots. Treatments were paired with a control and replicated at 2 sites within 3 residential properties for a total of 6 replicates. All mosquito larvae were removed and counted weekly, and a representative sample was identified in the laboratory. Complete control of Aedes species was achieved for 4 and 5 months in all tires and pots, respectively.

Potent and selective nonpeptide inhibitors of caspases 3 and 7 inhibit apoptosis and maintain cell functionality

Caspases have been strongly implicated to play an essential role in apoptosis. A critical question regarding the role(s) of these proteases is whether selective inhibition of an effector caspase(s) will prevent cell death. We have identified potent and selective non-peptide inhibitors of the effector caspases 3 and 7. The inhibition of apoptosis and maintenance of cell functionality with a caspase 3/7-selective inhibitor is demonstrated for the first time, and suggests that targeting these two caspases alone is sufficient for blocking apoptosis. Furthermore, an x-ray co-crystal structure of the complex between recombinant human caspase 3 and an isatin sulfonamide inhibitor has been solved to 2.8-A resolution. In contrast to previously reported peptide-based caspase inhibitors, the isatin sulfonamides derive their selectivity for caspases 3 and 7 by interacting primarily with the S(2) subsite, and do not bind in the caspase primary aspartic acid binding pocket (S(1)). These inhibitors blocked apoptosis in murine bone marrow neutrophils and human chondrocytes. Furthermore, in camptothecin-induced chondrocyte apoptosis, cell functionality as measured by type II collagen promoter activity is maintained, an activity considered essential for cartilage homeostasis. These data suggest that inhibiting chondrocyte cell death with a caspase 3/7-selective inhibitor may provide a novel therapeutic approach for the prevention and treatment of osteoarthritis, or other disease states characterized by excessive apoptosis.

Incorporating veterinary preventive dental instruction into a traditional dental hygiene program

A traditional dental hygiene program at the University of Texas Health Science Center, San Antonio, (UTHSCSA) incorporates veterinary preventive dental instruction into its community dentistry course. Students in the Certificate in Dental Hygiene Program attend two hours of didactic instruction on veterinary dentistry during the fall semester of their final year. The following spring semester students may choose a rotation in a veterinary clinic as one of their optional alternative practice sites. In addition, students are given the opportunity to participate in community service activities that are structured around veterinary dental care.

The use of antioxidant nutrients to prevent and treat cancers of the aerodigestive tract

Detection and prevention of oral cancer is an integral part of dental hygiene practice. Currently, much is known about the etiology and prevention of cancers of the aerodigestive tract. Poor nutrition is responsible for one-third of all cases. Antioxidant nutrients are assuming more importance in cancer research, including those of the aerodigestive tract. This review article will provide current information on antioxidant nutrients and their possible role as a chemopreventive agent in the development and treatment of oral cancer. In addition, recommendations will be made for incorporating nutrition education into dental hygiene practice.

Bovine insulin and porcine or human insulin prime distinct CD4(+) T cell subsets in C57BL/6 mice

H-2(b) mice produce insulin-specific antibody when injected with bovine but not porcine or human insulin. Nevertheless, CD4(+) T cells have been cloned from C57BL/6 mice primed with porcine, human, and bovine insulin. Here we tested the hypothesis that CD4(+) T cells from C57BL/6 mice primed with porcine or human insulin are functionally distinct from those primed with bovine insulin. Our results show that variants of insulin that stimulate antibody responses induced Th2 clones, whereas variants of insulin that fail to stimulate antibody induced Th0 clones. Th0 clones triggered delayed-type hypersensitivity (DTH) in adoptive recipients, whereas Th2 clones did not. Insulin variants that primed Th0 clones also directly primed for DTH responses, while variants that activated Th2 clones did not. Thus, induction of Th2 clones correlated with the ability of mice to make antibody responses to insulin while development of Th0 clones correlated with DTH responses and the failure to produce antibody.

Relationship between quality of life and depression in patients with head and neck cancer

OBJECTIVE

This study describes the relationship between health-related quality of life (HRQOL) and depression in patients following major surgery for head and neck cancer.

DESIGN

Cross-sectional study using medical chart review, patient interview, and test administration.

METHOD

Fifty patients were evaluated 6 months to 6 years following surgery using one global HRQOL measure (The Functional Assessment of Cancer Therapy-General [FACT-G]); three disease-specific measures of HRQOL (the HN module of the FACT [FACT-HNS], The University of Washington Quality of Life Scale [UWQOL], and The Performance Status Scale for Head and Neck Cancer); and one measure of depression (The Beck Depression Inventory [BDI]).

RESULTS

The study population showed a high occurrence of depressive symptoms (22%). A negative correlation existed between the BDI and HRQOL as measured by the FACT-G (r = -0.49, P < .001) and the UWQOL (r = -0.44, P = .003). When somatic symptoms of depression were removed, the BDI remained correlated with HRQOL and was most highly correlated with the Emotional Well-Being (EWB) subscale of the FACT-G (r = -0.42, P = .003). There was no correlation between clinician judgments of EWB and any patient-rated measures of HRQOL or depression.

CONCLUSIONS

Results demonstrate an inverse relationship between patient-reported HRQOL and depression. The lack of correlation between physician and patient ratings of HRQOL and EWB stresses the importance of obtaining patient ratings in addition to traditional clinician ratings when assessing outcomes. Finally, the multidimensional construction of the FACT with its specific subscales may make it a useful clinical tool for assessing patient status and augmenting patient interviews.

Effects of platelet activating factor on vascular permeability of the middle ear mucosa

Platelet activating factor (PAF), a potent inflammatory mediator, seems to play a significant role in the pathogenesis of otitis media with effusion (OME), along with other inflammatory mediators such as leukotrienes and prostaglandins. The purpose of this study was to investigate the effect of PAF on the vascular permeability of middle ear mucosa, in an experimental OME model using chinchillas. We injected PAF in doses of 1, 4, 8, and 16 micrograms and normal saline as a control into the bullae of chinchillas. Vascular permeability was measured by the Evans blue vital dye technique. All the PAF-injected animals showed a significant increase in middle ear vascular permeability compared to the control group. This study demonstrated that PAF in the middle ear cavity contributes significantly to the development of OME by increasing the vascular permeability of the middle ear mucosa.

Domoic acid: neurobehavioral and neurohistological effects of low-dose exposure in adult rats

Adult rats treated IP with domoic acid at 0, 0.22, 0.65, or 1.32 mg/kg were tested for passive avoidance (PA), auditory startle (AS), or conditioned avoidance (CAR) behaviors. Clinical signs were observed only at the 1.32 mg/kg dose level. Within 24 h of dosing, rats surviving a dose of 1.32 mg/kg exhibited transient decreased body weight and exaggerated AS responding. Startle latency and habituation, PA, and CAR were not affected. Examination of brains from six rats per group revealed a subset (2/6) of animals receiving 1.32 mg/kg domoic acid with degenerating neurons in the hippocampal CA1/CA3 subregions and gliosis. The decreased body weight and increased startle suggest a hyperreactivity syndrome possibly related to neuronal degeneration in the hippocampus. In a separate experiment, domoic acid at an IP dose of 0.93 mg/kg was found to produce hypomotility in addition to a decrease in body weight. Both effects were reduced by pretreatment with scopolamine (2 mg/kg), but not with caffeine (30 mg/kg), indicating a possible cholinergic involvement in domoate's toxicity.

Factors related to quality of life and functional status in 50 patients with head and neck cancer

Quality of life (QOL) and functional status (FS) have become important outcome measures in cancer therapy. Valid and reliable instruments recently have been developed for examining QOL and FS in patients with head and neck (HN) cancer. The present study evaluated the relationships of QOL and FS to physical and psychological variables assumed to affect QOL and FS. Fifty patients were evaluated up to 6 years after HN cancer surgery using one general QOL instrument and three HN-specific instruments. Analysis of variance showed physical variables such as tumor site to be related to HN-specific scores, while psychosocial variables such as marital status were related to general QOL scores (P < or = .05). Several relationships were seen between physical or psychosocial variables and FS or QOL measures; however the relationships were not as strong or direct as expected.

Quality of life and functional status measures in patients with head and neck cancer

OBJECTIVE

To assess the relationship among three validated head and neck-specific measures of functional status and a general measure of quality of life in patients with head and neck cancer.

DESIGNS

Cross-sectional study using medical chart review, patient interview, and test administration.

SETTING

Academic tertiary referral center.

PARTICIPANTS

Fifty adults patients 3 months to 6 years after major surgery for head and neck cancer.

MAIN OUTCOME MEASURE

Scores from a general measure of quality of life (the Functional Assessment of Cancer Therapy), a subscale specific to head and neck cancer, the University of Washington Quality of Life Questionnaire, and the Performance Status Scale for Head and Neck Cancer Patients.

RESULTS

The disease-specific measures of functional status correlate well with one another. However, there were low correlations between the Functional Assessment of Cancer Therapy and the disease-specific measures, indicating that general and disease-specific instruments contribute unique information about quality of life.

CONCLUSION

A general measure of quality of life augments information obtained by disease-specific instruments by interpreting functional status in the broader scope of the patient's life.

Acoustic neuroma volume: MRI-based calculations and clinical implications

This study developed a technique for magnetic resonance imaging (MRI)-based volume calculation and defined the specific volume-diameter relationship in acoustic neuromas (AN). Computer-assisted measurement calculated the area of tumor in each MRI slice. Volume was determined by multiplying area by slice interval. The technique was validated by imaging known volumes of gadolinium. The precision was greater than 95%. Our volume calculations revealed a specific volume-diameter relationship in ANs. The following conclusions can be drawn: 1. our technique can accurately determine AN tumor volume; 2. the AN volume-diameter relationship is a specific function and cannot be predicted by assumptions of tumor shape; 3. the volume-diameter relationship should be combined with clinical data to determine the "break point" at which small increments of diameter produce significant clinical sequelae.

Immature trichoepithelioma: report of six cases

We report 6 cases of an immature variant of trichoepithelioma which histologically appears to show differentiation toward the primitive hair germ. The lesions presented in mature adults (mean age 44 years). Four occurred in men and 2 in women. Four lesions occurred on extremities, an unusual location for trichoepitheliomas. Histologically, the lesions were characterized by well-circumscribed, but unencapsulated, dermal collections of small tumor lobules composed of basaloid cells with invaginations resembling primitive dermal hair papillae. There was no adenoidal growth pattern or horn cyst formation. The separation of the immature lesions from those of classical trichoepithelioma and basal cell carcinoma can be made if multiple morphological features are considered; no one particular finding is diagnostic. The major differential features between the immature trichoepithelioma and basal cell carcinoma are circumscription, tumor lobule uniformity, occasional immature hair germs, and lack of retraction artifact of the tumor lobules from the stroma. The differential features between the immature and classical trichoepithelioma are less conspicuous. The immature form typically exhibits no horn cysts, displays fewer primitive hair structures, and lacks the adenoidal growth patterns of the tumor lobules which are usually present in the classical trichoepitheliomas.

Determining intraocular lens power within the eye

A method is described for determining the power of an intraocular lens (IOL) within the eye by measuring the horizontal dimension of the corneal reflected image (Purkinje-Sanson I) and the anterior IOL reflected image (Purkinje-Sanson III) as seen through a standard slitlamp with a target positioned 68 mm anterior to the focal plane of the biomicroscope. The horizontal K-reading (at 180 degrees) and the anterior chamber depth are the two other parameters necessary to calculate the exact power of the IOL. Seven tables that use these four measurements have been provided, eliminating the need for complex calculations. To determine the accuracy of this technique, ten implanted IOLs ranging from 9 diopters (D) to 27 D were chosen and their powers calculated; these calculated values were then compared to the actual IOL powers. The largest error was 0.5 D and the average error was 0.17 D.

The composition of the ceramides from human stratum corneum and from comedones

Human epidermal surface lipids were collected by an ethanol wash and the ceramides were quantified by thin-layer chromatography-photodensitometry. Six ceramide fractions were isolated and the structural components of each were analyzed in detail. The most unusual of the epidermal ceramides contained a sphingosine base with amide-linked 30- and 32-carbon omega-hydroxyacids and an ester-linked nonhydroxyacid, 41% of which was linoleic acid. The proportion of linoleic acid in the analogous ceramide from comedones was 6%. This supports the hypothesis that a localized insufficiency of linoleic acid in the follicular epithelium is an etiologic factor in comedogenesis.

Human stratum corneum polar lipids and desquamation

The ceramides and steryl-sulfate components from desquamated and cohesive human stratum corneum were examined using a combination of chemical and chromatographic means. Six structurally distinct series of ceramides were identified, and the relative amounts of these species, as measured by quantitative thin-layer chromatography, did not differ in cohesive and desquamated stratum corneum. In contrast, the level of cholesteryl sulfate was significantly reduced in the desquamated material. The results are in accord with the hypothesis that cholesteryl sulfate serves in cell-to-cell cohesion within the stratum corneum, and its hydrolysis may be necessary to permit shedding of cells from the surface.