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Type 1 diabetes (T1D) has a strong genetic component and the major locus lies in the HLA DQB1 region. We found earlier an increased apoptosis with decreased viability and function of the CD4+CD25+high T-cell subset (Treg) in human subjects with recent-onset T1D and in multiple autoantibody-positive, high at-risk individuals. Tregs normally inhibit or delay onset of T1D in animal models and increased Treg apoptosis could bring on or accelerate disease from effector T-cell-mediated destruction of insulin-producing beta cells. In this study, we test the hypothesis that HLA DQB1 genotypes are associated with increased CD4+CD25+high T-cell apoptosis. HLA DQ-based genetic risk status was significantly associated with CD4+CD25+high T-cell apoptosis, after adjustment for age, gender and phenotypic status (n=83, F=4.04 (d.f.=3), P=0.01). Unaffected, autoantibody-negative high risk HLA DQB1 control subjects showed increased CD4+CD25+high apoptosis levels compared with low risk HLA DQB1 control subjects (n=26, P=0.002), confirming that the association precedes disease. The association of specific HLA DQB1 genotypes with Treg apoptosis was also tested, showing significance for HLA DQB1*0302, DQB1*0201 and HLA DQB1*0602 alleles. Our study shows an association of HLA DQB1 genotypes with CD4+CD25+high T-cell apoptosis, which implicates CD4+CD25+high T-cell apoptosis as a new intermediate trait for T1D.Genes and Immunity (2009) 10, 334–340; doi:10.1038/gene.2009.14; published online 19 March 2009 [ABSTRACT FROM AUTHOR]

Because type 1 diabetes (T1D) is a chronic, autoimmune, T cell-mediated disease, interventions affecting T cells are expected to modulate the immune cascade and lead to disease remission. We propose that increased CD4+ CD25+high T cell apoptosis, a trait we discovered in recent-onset T1D subjects, reflects T1D partial remission within the first 6 months after diagnosis. Apoptosis of forkhead box P3 (FoxP3)+ CD4+ CD25+high T cells, in addition to total daily doses of insulin (TDD), blood glucose, HbA1c and age, were measured in 45 subjects with T1D at various times after diagnosis. Sixteen healthy control subjects were also recruited to the study. Higher CD4+ CD25+high T cell apoptosis levels were detected within the first 6 months of diagnosis (odds ratio = 1·39, P = 0·009), after adjustment for age, TDD and HbA1c. A proportional hazards model confirmed that the decline of apoptosis after diagnosis of T1D was related significantly to survival time (hazards ratio = 1·08, P = 0·014), with TDD and age also contributing to survival. During this time there was an inverse relationship between CD4+ CD25+high T cell apoptosis with TDD ( r = −0·39, P = 0·008). The CD4+ CD25+high T cell apoptosis levels decline significantly after the first 6 months from diagnosis of T1D and may help in the close monitoring of autoimmunity. In parallel, there is an increase in TDD during this time. We also propose that CD4+ CD25+high T cell apoptosis assay can be used to gauge the efficacy of the several immune tolerance induction protocols, now under way. [ABSTRACT FROM AUTHOR]

Human interleukin 12 and interleukin 23 (IL12/23) influence susceptibility or resistance to multiple diseases. However, the reasons underlying individual differences in IL12/23 sensitivity remain poorly understood. Here we report that in human peripheral blood mononuclear cells (PBMCs) and inflamed lungs, the majority of interleukin-12 receptor β1 (IL12RB1) mRNAs contain a number of RNA-DNA differences (RDDs) that concentrate in sequences essential to IL12Rβ1's binding of IL12p40, the protein subunit common to both IL-12 and IL-23. IL12RB1 RDDs comprise multiple RDD types and are detectable by next-generation sequencing and classic Sanger sequencing. As a consequence of these RDDs, the resulting IL12Rβ1 proteins have an altered amino acid sequence that could not be predicted on the basis of genomic DNA sequencing alone. Importantly, the introduction of RDDs into IL12RB1 mRNAs negatively regulates IL12Rβ1's binding of IL12p40 and is sensitive to activation. Collectively, these results suggest that the introduction of RDDs into an individual's IL12RB1 mRNA repertoire is a novel determinant of IL12/23 sensitivity.

This collaborative, community-engaged project developed and tested a Culturally-Tailored Treatment (CTT) for American Indian/Alaska Native (AI/AN) smokers in the Menominee tribal community. One hundred three adult AI/AN smokers were randomized to receive either Standard Treatment ( n = 53) or CTT ( n = 50) for smoking cessation. Both treatment conditions included 12 weeks of varenicline and four individual counseling sessions but differed in terms of cultural tailoring of the counseling. The primary outcome was 7-day biochemically-confirmed point-prevalence abstinence (PPA) at the 6-month end-of-study visit. Both intention-to-treat (ITT) and responder-only analyses were conducted. There were no statistically significant group differences in 7-day PPA. The overall ITT abstinence rate at 6 months was 20%; the responder-only rate was 42%. The current study represents the first randomized smoking cessation clinical trial testing a culturally-tailored smoking cessation intervention designed for a specific AI/AN tribal community that combined FDA-approved cessation medication (varenicline) and innovative cultural intervention components.

Introduction: Cancer incidence and mortality rates for American Indians in the Northern Plains region of the United States are among the highest in the nation. Reliable cancer surveillance data are essential to help reduce this burden; however, racial data in state cancer registries are often misclassified, and cases are often underreported., Methods: We used a community-based participatory research approach to conduct a retrospective ascertainment of cancer cases in clinic medical records over a 9-year period (1995-2003) and compared the results with the state cancer registry to evaluate missing or racially misclassified cases. Six tribal and/or urban Indian clinics participated in the study. The project team consisted of participating clinics, a state cancer registry, a comprehensive cancer center, an American Indian/Alaska Native Leadership Initiative on Cancer, and a set of diverse organizational partners. Clinic personnel were trained by project staff to accurately identify cancer cases in clinic records. These records were then matched with the state cancer registry to assess misclassification and underreporting., Results: Forty American Indian cases were identified that were either missing or misclassified in the state registry. Adding these cases to the registry increased the number of American Indian cases by 21.3% during the study period (P = .05)., Conclusions: Our results indicate that direct reporting of cancer cases by tribal and urban Indian health clinics to a state cancer registry improved the quality of the data available for cancer surveillance. Higher-quality data can advance the efforts of cancer prevention and control stakeholders to address disparities in Native communities.

The Menominee Indian Tribe of Wisconsin has the highest smoking rate in the state. To address the resultant health disparities, the tribe conducted a qualitative pilot project to examine tobacco use. The findings indicated mainstream models of addiction did not capture the tribe's context well; the Indigenist Stress-Coping Model was most applicable. Participants suggested that Menominee-centric ways of knowing related to commercial and sacred tobacco use should be included in all levels of prevention as a key strategy. Recommendations include primary prevention targeted specifically to youth, pregnant women, and adults who care for children, as well as access to commercial tobacco products.

IL12RB1 is essential for human resistance to multiple intracellular pathogens, including Mycobacterium tuberculosis. In its absence, the proinflammatory effects of the extracellular cytokines IL-12 and IL-23 fail to occur, and intracellular bacterial growth goes unchecked. Given the recent observation that mouse leukocytes express more than one isoform from il12rb1, we examined whether primary human leukocytes similarly express more than one isoform from IL12RB1. We observed that human leukocytes express as many as 13 distinct isoforms, the relative levels of each being driven by inflammatory stimuli both in vitro and in vivo. Surprisingly, the most abundant isoform present before stimulation is a heretofore uncharacterized intracellular form of the IL-12R (termed "isoform 2") that presumably has limited contact with extracellular cytokine. After stimulation, primary PBMCs, including the CD4(+), CD8(+), and CD56(+) lineages contained therein, alter the splicing of IL12RB1 RNA to increase the relative abundance of isoform 1, which confers IL-12/IL-23 responsiveness. These data demonstrate both a posttranscriptional mechanism by which cells regulate their IL-12/IL-23 responsiveness, and that leukocytes primarily express IL12RB1 in an intracellular form located away from extracellular cytokine.

Regulatory T cells (Tregs) are critical mediators of immune tolerance to self-antigens. In addition, they are crucial regulators of the immune response following an infection. Despite efforts to identify unique surface marker on Tregs, the only unique feature is their ability to suppress the proliferation and function of effector T cells. While it is clear that only in vitro assays can be used in assessing human Treg function, this becomes problematic when assessing the results from cross-sectional studies where healthy cells and cells isolated from subjects with autoimmune diseases (like Type 1 Diabetes-T1D) need to be compared. There is a great variability among laboratories in the number and type of responder T cells, nature and strength of stimulation, Treg:responder ratios and the number and type of antigen-presenting cells (APC) used in human in vitro suppression assays. This variability makes comparison between studies measuring Treg function difficult. The Treg field needs a standardized suppression assay that will work well with both healthy subjects and those with autoimmune diseases. We have developed an in vitro suppression assay that shows very little intra-assay variability in the stimulation of T cells isolated from healthy volunteers compared to subjects with underlying autoimmune destruction of pancreatic β-cells. The main goal of this piece is to describe an in vitro human suppression assay that allows comparison between different subject groups. Additionally, this assay has the potential to delineate a small loss in nTreg function and anticipate further loss in the future, thus identifying subjects who could benefit from preventive immunomodulatory therapy. Below, we provide thorough description of the steps involved in this procedure. We hope to contribute to the standardization of the in vitro suppression assay used to measure Treg function. In addition, we offer this assay as a tool to recognize an early state of immune imbalance and a potential functional biomarker for T1D.

Background: In type 1 diabetes (T1D), a prototypic autoimmune disease, effector T cells destroy beta cells. Normally, CD4(+)CD25(+high), or natural regulatory T cells (Tregs), counter this assault. In autoimmunity, the failure to suppress CD4(+)CD25(low) T cells is important for disease development. However, both Treg dysfunction and hyperactive responder T-cell proliferation contribute to disease., Methods/principal Findings: We investigated human CD4(+)CD25(low) T cells and compared them to CD4(+)CD25(-) T cells in otherwise equivalent in vitro proliferative conditions. We then asked whether these differences in suppression are exacerbated in T1D. In both single and co-culture with Tregs, the CD4(+)CD25(low) T cells divided more rapidly than CD4(+)CD25(-) T cells, which manifests as increased proliferation/reduced suppression. Time-course experiments showed that this difference could be explained by higher IL-2 production from CD4+CD25(low) compared to CD4+CD25- T cells. There was also a significant increase in CD4+CD25(low) T-cell proliferation compared to CD4+CD25- T cells during suppression assays from RO T1D and at-risk subjects (n = 28, p = 0.015 and p = 0.024 respectively)., Conclusions/significance: The in vitro dual suppression assays proposed here could highlight the impaired sensitivity of certain responder T cells to the suppressive effect of Tregs in human autoimmune diseases.

CD4+CD25+(high) regulatory T cells (Tregs) play a pivotal role in the control of the immune response. A growing body of evidence suggests the reduced function of these cells in autoimmune diseases, including type 1 diabetes (T1D). Restoration of their function can potentially delay further disease development. In the present study, we have converted conventional effector T cells into induced Tregs (iTregs) in recent-onset (RO) T1D (n=9) and compared them with the same cells generated in controls (n=12) and in long-standing (LS) T1D subjects (n=9). The functional potential of in-vitro-generated Tregs was measured by using an in vitro proliferation assay. We noted that the suppressive potential of iTregs exceeded that of natural regulatory T cells (nTregs) only in the RO T1D subjects. We showed that iTregs from RO T1D subjects had increased expression of Foxp3, E3 ubiquitin ligase (ITCH) and TGF-beta-inducible early gene 1 (TIEG1) compared with control and LS T1D subjects. We also expanded natural, thymically derived Tregs (nTregs) and compared the functional ability of these cells between subject groups. Expanded cells from all three subject groups were suppressive. RO T1D subjects were the only group in which both iTregs and expanded Tregs were functional, suggesting that the inflammatory milieu impacts in vitro Treg generation. Future longitudinal studies should delineate the actual contribution of the stage of disease to the quality of in-vitro-generated Tregs.

The transcription factor Foxp3 is essential for the development of functional, natural Treg (nTreg), which plays a prominent role in self-tolerance. Suppressive Foxp3(+) Treg cells can be generated from naïve T cells ex vivo, following TCR and TGF-beta1 stimulations. However, the molecular contributions from the different arms of these pathways leading to Foxp3 expression are not fully understood. TGF-beta1-activated Smad3 plays a major role in the expression of Foxp3, since TGF-beta1-induced-Treg generation from Smad3(-/-) mice is markedly reduced and abolished by inactivating Smad2. In the TCR pathway, deletion of Bcl10, which activates NF-kappaB, markedly reduces both IL-2 and Foxp3 production. However, partial rescue of Foxp3 expression occurs on addition of exogenous IL-2. TGF-beta1 significantly attenuates NF-kappaB binding to the Foxp3 promoter, while inducing Foxp3 expression. Furthermore, deletion of p50, a NF-kappaB subunit, results in increased Foxp3 expression despite a decline in the IL-2 production. We posit several TCR-NF-kappaB pathways, some increasing (Bcl10-IL-2-Foxp3) while others decreasing (p50-Foxp3) Foxp3 expression, with the former predominating. A better understanding of Foxp3 regulation could be useful in dissecting the cause of Treg dysfunction in several autoimmune diseases and for generating more potent TGF-beta1-induced-Treg cells for therapeutic purposes.

Background: Type 1 diabetes (T1D) is a T-cell mediated autoimmune disease targeting the insulin-producing pancreatic beta cells. Naturally occurring FOXP3(+)CD4(+)CD25(high) regulatory T cells (T(regs)) play an important role in dominant tolerance, suppressing autoreactive CD4(+) effector T cell activity. Previously, in both recent-onset T1D patients and beta cell antibody-positive at-risk individuals, we observed increased apoptosis and decreased function of polyclonal T(regs) in the periphery. Our objective here was to elucidate the genes and signaling pathways triggering apoptosis in T(regs) from T1D subjects., Principal Findings: Gene expression profiles of unstimulated T(regs) from recent-onset T1D (n = 12) and healthy control subjects (n = 15) were generated. Statistical analysis was performed using a Bayesian approach that is highly efficient in determining differentially expressed genes with low number of replicate samples in each of the two phenotypic groups. Microarray analysis showed that several cytokine/chemokine receptor genes, HLA genes, GIMAP family genes and cell adhesion genes were downregulated in T(regs) from T1D subjects, relative to control subjects. Several downstream target genes of the AKT and p53 pathways were also upregulated in T1D subjects, relative to controls. Further, expression signatures and increased apoptosis in T(regs) from T1D subjects partially mirrored the response of healthy T(regs) under conditions of IL-2 deprivation. CD4(+) effector T-cells from T1D subjects showed a marked reduction in IL-2 secretion. This could indicate that prior to and during the onset of disease, T(regs) in T1D may be caught up in a relatively deficient cytokine milieu., Conclusions: In summary, expression signatures in T(regs) from T1D subjects reflect a cellular response that leads to increased sensitivity to apoptosis, partially due to cytokine deprivation. Further characterization of these signaling cascades should enable the detection of genes that can be targeted for restoring T(reg) function in subjects predisposed to T1D.

Background: American Indian and Alaska Native cancer incidence data are limited by underreporting and misclassification. These populations also suffer from a history of research abuse., Objectives: The project's goal was to use community-based participatory research (CBPR) to assess the local burden of cancer in the American Indian communities in Wisconsin and assess the accuracy of Wisconsin American Indian cancer data., Methods: Thirteen organizations partnered to conduct a retrospective review of American Indian clinics cancer cases. A match of the clinic identified cases with Wisconsin Cancer Reporting System records was then conducted., Lessons Learned: Relationship building, mutual education, and local engagement in data interpretation were significant factors in this project achieving its objectives and laying a foundation for future research partnerships., Conclusions: This project demonstrates the successful application of CBPR in a complex multisite project with multiple partners using collective resources to address cancer health disparities.

Because type 1 diabetes (T1D) is a chronic, autoimmune, T cell-mediated disease, interventions affecting T cells are expected to modulate the immune cascade and lead to disease remission. We propose that increased CD4(+) CD25(+high) T cell apoptosis, a trait we discovered in recent-onset T1D subjects, reflects T1D partial remission within the first 6 months after diagnosis. Apoptosis of forkhead box P3 (FoxP3)(+) CD4(+) CD25(+high) T cells, in addition to total daily doses of insulin (TDD), blood glucose, HbA1c and age, were measured in 45 subjects with T1D at various times after diagnosis. Sixteen healthy control subjects were also recruited to the study. Higher CD4(+) CD25(+high) T cell apoptosis levels were detected within the first 6 months of diagnosis (odds ratio = 1.39, P = 0.009), after adjustment for age, TDD and HbA1c. A proportional hazards model confirmed that the decline of apoptosis after diagnosis of T1D was related significantly to survival time (hazards ratio = 1.08, P = 0.014), with TDD and age also contributing to survival. During this time there was an inverse relationship between CD4(+) CD25(+high) T cell apoptosis with TDD (r = -0.39, P = 0.008). The CD4(+) CD25(+high) T cell apoptosis levels decline significantly after the first 6 months from diagnosis of T1D and may help in the close monitoring of autoimmunity. In parallel, there is an increase in TDD during this time. We also propose that CD4(+) CD25(+high) T cell apoptosis assay can be used to gauge the efficacy of the several immune tolerance induction protocols, now under way.

Background: In experimental models, Type 1 diabetes T1D can be prevented by adoptive transfer of CD4+CD25+ (FoxP3+) suppressor or regulatory T cells. Recent studies have found a suppression defect of CD4+CD25+(high) T cells in human disease. In this study we measure apoptosis of CD4+CD25+(high) T cells to see if it could contribute to reduced suppressive activity of these cells., Methods and Findings: T-cell apoptosis was evaluated in children and adolescent 35 females/40 males subjects comprising recent-onset and long-standing T1D subjects and their first-degree relatives, who are at variable risk to develop T1D. YOPRO1/7AAD and intracellular staining of the active form of caspase 3 were used to evaluate apoptosis. Isolated CD4+CD25+(high) and CD4+CD25- T cells were co-cultured in a suppression assay to assess the function of the former cells. We found that recent-onset T1D subjects show increased apoptosis of CD4+CD25+(high) T cells when compared to both control and long-standing T1D subjects p<0.0001 for both groups. Subjects at high risk for developing T1D 2-3Ab+ve show a similar trend p<0.02 and p<0.01, respectively. On the contrary, in long-standing T1D and T2D subjects, CD4+CD25+(high) T cell apoptosis is at the same level as in control subjects p = NS. Simultaneous intracellular staining of the active form of caspase 3 and FoxP3 confirmed recent-onset FoxP3+ve CD4+CD25+(high) T cells committed to apoptosis at a higher percentage 15.3+/-2.2 compared to FoxP3+ve CD4+CD25+(high) T cells in control subjects 6.1+/-1.7 p<0.002. Compared to control subjects, both recent-onset T1D and high at-risk subjects had significantly decreased function of CD4+CD25+(high) T cells p = 0.0007 and p = 0.007, respectively., Conclusions: There is a higher level of ongoing apoptosis in CD4+CD25+(high) T cells in recent-onset T1D subjects and in subjects at high risk for the disease. This high level of CD4+CD25+(high) T-cell apoptosis could be a contributing factor to markedly decreased suppressive potential of these cells in recent-onset T1D subjects.

We have created an immunology-related microarray chip containing primarily known genes with well-studied functional properties. By looking at known genes rather than expressed sequence tags, we hope to gain a better understanding of immunological pathways and how they work. The immunology gene chip contains genes from the following functional categories: T cell genes; B cell genes; dendritic cell genes; chemokine and cytokine genes; apoptosis genes; cell cycle genes; cell interaction genes; general hematology and immunology genes; and adhesion genes. We have also developed a novel three-color cDNA array platform in which arrays are directly visualized before hybridization, which allows us to select only high-quality chips for our experiments. In an effort to provide quantitative quality control for each array element as well as the entire chip, we have developed Matarray, a software package for image processing and data acquisition. With Matarray, we have built a quantitative data filtering and normalization scheme that has proved to be more efficient than the existing methods. The list of immunology chip genes is available from the authors.

To determine whether N-terminal sequences are involved in the transmembrane signaling mechanism of EnvZ, the nucleotide sequences of envZ genes from several enteric bacteria were determined. Comparative analysis revealed that the amino acid sequence between Pro41 and Glu53 was highly conserved. To further analyze the role of the conserved sequence, envZ of Escherichia coli was subjected to random PCR mutagenesis and mutant alleles that produced a high-osmolarity phenotype, in which ompF was repressed, were isolated. The mutations identified clustered within, as well as adjacent to, the Pro41-to-Glu53 sequence. These findings suggest that the conserved Pro41-to-Glu53 sequence is involved in the signal transduction mechanism of EnvZ.

The function and novel regulation of OpnP of the symbiotic/pathogenic bacterium, Xenorhabdus nematophilus was studied. In vitro pore-function analysis of purified OpnP indicated that the single-channel-conductance values were similar to that measured for the porin protein, OmpF, of Esherichia coli. Nucleotide sequence analysis revealed that the mature OpnP protein contained 348 amino acid residues and shared 55% amino acid sequence identity with OmpF. Similar to ompF, opnP mapped between asnS and aspC. The 16 transmembrane beta-sheet structures and the internal loop 3 were highly conserved, while the remaining external loop domains were more divergent. Primer extension analysis identified the start site of transcription of opnP. A sigma 70-type promoter, a perfect 20 bp OmpR-binding site, and a binding site for the antisense molecule, micF RNA, were found in the upstream region of opnP. While the overall sequence identity of the asn-opnP-aspC region was high, the intergenic region between asnS and opnP had diverged markedly. The asnS-opnP region was 313 bp shorter than the intergenic region between asnS and ompF and lacked the OmpR-binding site that is required for ompF repression by high osmolarity in E. coli. Results from osmolarity-shift experiments indicated that OpnP was not repressed by high osmolarity. It was also found that OpnP was thermally regulated.