Muscle-specific, liver-detargeted adeno-associated virus gene therapy rescues Pompe phenotype in adult and neonate Gaa-/- mice

Pompe disease (PD) is a neuromuscular disorder caused by acid α-glucosidase (GAA) deficiency. Reduced GAA activity leads to pathological glycogen accumulation in cardiac and skeletal muscles responsible for severe heart impairment, respiratory defects, and muscle weakness. Enzyme replacement therapy with recombinant human GAA (rhGAA) is the standard-of-care treatment for PD, however, its efficacy is limited due to poor uptake in muscle and the development of an immune response. Multiple clinical trials are ongoing in PD with adeno-associated virus (AAV) vectors based on liver- and muscle-targeting. Current gene therapy approaches are limited by liver proliferation, poor muscle targeting, and the potential immune response to the hGAA transgene. To generate a treatment tailored to infantile-onset PD, we took advantage of a novel AAV capsid able to increase skeletal muscle targeting compared to AAV9 while reducing liver overload. When combined with a liver-muscle tandem promoter (LiMP), and despite the extensive liver-detargeting, this vector had a limited immune response to the hGAA transgene. This combination of capsid and promoter with improved muscle expression and specificity allowed for glycogen clearance in cardiac and skeletal muscles of Gaa-/- adult mice. In neonate Gaa-/- , complete rescue of glycogen content and muscle strength was observed 6 months after AAV vector injection. Our work highlights the importance of residual liver expression to control the immune response toward a potentially immunogenic transgene expressed in muscle. In conclusion, the demonstration of the efficacy of a muscle-specific AAV capsid-promoter combination for the full rescue of PD manifestation in both neonate and adult Gaa-/- provides a potential therapeutic avenue for the infantile-onset form of this devastating disease.

Accelerating Colorectal Cancer Screening and Follow-up through Implementation Science (ACCSIS) in Appalachia: protocol for a group randomized, delayed intervention trial

Appalachian regions of Kentucky and Ohio are hotspots for colorectal cancer (CRC) mortality in the USA. Screening reduces CRC incidence and mortality; however, screening uptake is needed, especially in these underserved geographic areas. Implementation science offers strategies to address this challenge. The aim of the current study was to conduct multi-site, transdisciplinary research to evaluate and improve CRC screening processes using implementation science strategies. The study consists of two phases (Planning and Implementation). In the Planning Phase, a multilevel assessment of 12 health centers (HC) (one HC from each of the 12 Appalachian counties) was conducted by interviewing key informants, creating community profiles, identifying HC and community champions, and performing HC data inventories. Two designated pilot HCs chose CRC evidence-based interventions to adapt and implement at each level (i.e., patient, provider, HC, and community) with evaluation relative to two matched control HCs. During the Implementation Phase, study staff will repeat the rollout process in HC and community settings in a randomized, staggered fashion in the remaining eight counties/HCs. Evaluation will include analyses of electronic health record data and provider and county surveys. Rural HCs have been reluctant to participate in research because of concerns about capacity; however, this project should demonstrate that research does not need to be burdensome and can adapt to local needs and HC abilities. If effective, this approach could be disseminated to HC and community partners throughout Appalachia to encourage the uptake of effective interventions to reduce the burden of CRC.

Deficiency of lncRNA SNHG12 impairs ischemic limb neovascularization by altering an endothelial cell cycle pathway

SNHG12, a long noncoding RNA (lncRNA) dysregulated in atherosclerosis, is known to be a key regulator of vascular senescence in endothelial cells (ECs). However, its role in angiogenesis and peripheral artery disease has not been elucidated. Hind-limb ischemia studies using femoral artery ligation (FAL) in mice showed that SNHG12 expression falls readily in the acute phase of the response to limb ischemia in gastrocnemius muscle and recovers to normal when blood flow recovery is restored to ischemic muscle, indicating that it likely plays a role in the angiogenic response to ischemia. Gain- and loss-of-function studies demonstrated that SNHG12 regulated angiogenesis — SNHG12 deficiency reduced cell proliferation, migration, and endothelial sprouting, whereas overexpression promoted these angiogenic functions. We identified SNHG12 binding partners by proteomics that may contribute to its role in angiogenesis, including IGF-2 mRNA–binding protein 3 (IGF2BP3, also known as IMP3). RNA-Seq profiling of SNHG12-deficient ECs showed effects on angiogenesis pathways and identified a strong effect on cell cycle regulation, which may be modulated by IMP3. Knockdown of SNHG12 in mice undergoing FAL using injected gapmeRs) decreased angiogenesis, an effect that was more pronounced in a model of insulin-resistant db/db mice. RNA-Seq profiling of the EC and non-EC compartments in these mice revealed a likely role of SNHG12 knockdown on Wnt, Notch, and angiopoietin signaling pathways. Together, these findings indicate that SNHG12 plays an important role in the angiogenic EC response to ischemia.

Hepatic expression of GAA results in enhanced enzyme bioavailability in mice and non-human primates

Pompe disease (PD) is a severe neuromuscular disorder caused by deficiency of the lysosomal enzyme acid alpha-glucosidase (GAA). PD is currently treated with enzyme replacement therapy (ERT) with intravenous infusions of recombinant human GAA (rhGAA). Although the introduction of ERT represents a breakthrough in the management of PD, the approach suffers from several shortcomings. Here, we developed a mouse model of PD to compare the efficacy of hepatic gene transfer with adeno-associated virus (AAV) vectors expressing secretable GAA with long-term ERT. Liver expression of GAA results in enhanced pharmacokinetics and uptake of the enzyme in peripheral tissues compared to ERT. Combination of gene transfer with pharmacological chaperones boosts GAA bioavailability, resulting in improved rescue of the PD phenotype. Scale-up of hepatic gene transfer to non-human primates also successfully results in enzyme secretion in blood and uptake in key target tissues, supporting the ongoing clinical translation of the approach.

Novel Lesional Transcriptional Signature Separates Atherosclerosis With and Without Diabetes in Yorkshire Swine and Humans

[Figure: see text].

Provider Practice and Perceptions of Pediatric Obesity in Appalachian Kentucky

OBJECTIVES

This study assessed providers' present practices and perceived needs in Appalachian Kentucky to identify the standard of care and implementation of expert recommendations for managing pediatric obesity.

METHODS

Questionnaire data were gathered from 28 providers at a pediatric obesity continuing medical education workshop in eastern Kentucky. We assessed current practices, perceived barriers to treatment, and needed resources for managing pediatric obesity.

RESULTS

Respondents reported mixed adherence to expert recommendations, with providers less frequently addressing family-reported barriers to change and assessing a family's readiness to change behaviors related to pediatric obesity. Respondents also reported service barriers related to patient motivation, lack of time with patients, and a lack of referral options. Finally, providers reported needing multiple community resources to better address pediatric obesity, including improved physical education programs, access to community recreation centers, additional referral resources for multidisciplinary care, and additional training in motivational techniques.

CONCLUSIONS

There remains a significant need for education and guidance regarding the implementation of expert recommendations for addressing pediatric obesity in Appalachian Kentucky. Providers reported needing multiple community resources, including improved physical education programs, access to community recreation centers, additional referral resources for multidisciplinary care, and additional training in motivational techniques. We discuss the implications for disseminating and implementing expert recommendations in rural eastern Kentucky, with an emphasis on the roles of behavioral health experts.

Dual muscle-liver transduction imposes immune tolerance for muscle transgene engraftment despite preexisting immunity

Immune responses to therapeutic transgenes are a potential hurdle to treat monogenic muscle disorders. These responses result from the neutralizing activity of transgene-specific B cells and cytotoxic T cells recruited upon gene transfer. We explored here how dual muscle-liver expression of a foreign transgene allows muscle transgene engraftment after adenoassociated viral vector delivery. We found in particular that induction of transgene-specific tolerance is imposed by concurrent muscle and liver targeting, resulting in the absence of CD8+ T cell responses to the transgene. This tolerance can be temporally decoupled, because transgene engraftment can be achieved in muscle weeks after liver transduction. Importantly, transgene-specific CD8+ T cell tolerance can be established despite preexisting immunity to the transgene. Whenever preexisting, transgene-specific CD4+ and CD8+ memory T cell responses are present, dual muscle-liver transduction turns polyclonal, transgene-specific CD8+ T cells into typically exhausted T cells with high programmed cell death 1 (PD-1) expression and lack of IFN-γ production. Our results demonstrate that successful transduction of muscle tissue can be achieved through liver-mediated control of humoral and cytotoxic T cell responses, even in the presence of preexisting immunity to the muscle-associated transgene.

Induction of tumor-specific CTL responses using the C-terminal fragment of Viral protein R as cell penetrating peptide

The discovery of tumor-associated antigens recognized by T lymphocytes opens the possibility of vaccinating cancer patients with defined antigens. However, one of the major limitation of peptide-based vaccines is the low immunogenicity of antigenic peptides. Interestingly, if these epitopes are directly delivered into the cytoplasm of antigen presenting cells, they can be efficiently presented via the direct MHC class I presentation pathway. To improve antigen entry, one promising approach is the use of cell penetrating peptides (CPPs). However, most studies use a covalent binding of the CPP with the antigen. In the present study, we focused on the C-terminal domain of Vpr which was previously demonstrated to efficiently deliver plasmid DNA into cells. We provide evidence that the peptides Vpr55-91 and Vpr55-82 possess the capacity of delivering proteins and epitopes into cell lines as well as into human primary dendritic cells, without the necessicity for a chemical linkage. Moreover, immunization of HLA-A2 transgenic mice with Vpr55-91 as the sole adjuvant is able to induce antigen-specific cytotoxic T lymphocytes against multiple tumor epitopes.

Cytosolic lipid droplets: from mechanisms of fat storage to disease

The lipid droplet (LD) is a phylogenetically conserved organelle. In eukaryotes, it is born from the endoplasmic reticulum, but unlike its parent organelle, LDs are the only known cytosolic organelles that are micellar in structure. LDs are implicated in numerous physiological and pathophysiological functions. Many aspects of the LD has captured the attention of diverse scientists alike and has recently led to an explosion in information on the LD biogenesis, expansion and fusion, identification of LD proteomes and diseases associated with LD biology. This review will provide a brief history of this fascinating organelle and provide some contemporary views of unanswered questions in LD biogenesis.

SCS3 and YFT2 link transcription of phospholipid biosynthetic genes to ER stress and the UPR

The ability to store nutrients in lipid droplets (LDs) is an ancient function that provides the primary source of metabolic energy during periods of nutrient insufficiency and between meals. The Fat storage-Inducing Transmembrane (FIT) proteins are conserved ER–resident proteins that facilitate fat storage by partitioning energy-rich triglycerides into LDs. FIT2, the ancient ortholog of the FIT gene family first identified in mammals has two homologs in Saccharomyces cerevisiae (SCS3 and YFT2) and other fungi of the Saccharomycotina lineage. Despite the coevolution of these genes for more than 170 million years and their divergence from higher eukaryotes, SCS3, YFT2, and the human FIT2 gene retain some common functions: expression of the yeast genes in a human embryonic kidney cell line promotes LD formation, and expression of human FIT2 in yeast rescues the inositol auxotrophy and chemical and genetic phenotypes of strains lacking SCS3. To better understand the function of SCS3 and YFT2, we investigated the chemical sensitivities of strains deleted for either or both genes and identified synthetic genetic interactions against the viable yeast gene-deletion collection. We show that SCS3 and YFT2 have shared and unique functions that connect major biosynthetic processes critical for cell growth. These include lipid metabolism, vesicular trafficking, transcription of phospholipid biosynthetic genes, and protein synthesis. The genetic data indicate that optimal strain fitness requires a balance between phospholipid synthesis and protein synthesis and that deletion of SCS3 and YFT2 impacts a regulatory mechanism that coordinates these processes. Part of this mechanism involves a role for SCS3 in communicating changes in the ER (e.g. due to low inositol) to Opi1-regulated transcription of phospholipid biosynthetic genes. We conclude that SCS3 and YFT2 are required for normal ER membrane biosynthesis in response to perturbations in lipid metabolism and ER stress.

The ability to form lipid droplets is a conserved property of eukaryotic cells that allows the storage of excess metabolic energy in a form that can be readily accessed. In adipose tissue, the storage of excess calories in lipid droplets normally protects other tissues from lipotoxicity and insulin resistance, but this protection is lost with chronic over-nutrition. The FAT storage-inducing transmembrane (FIT) proteins were recently identified as a conserved family of proteins that reside in the lipid bilayer of the endoplasmic reticulum and are implicated in lipid droplet formation. In this work we show that specific functions of the FIT proteins are conserved between yeast and humans and that SCS3 and YFT2, the yeast homologs of mammalian FIT2, are part of a large genetic interaction network connecting lipid metabolism, vesicle trafficking, transcription, and protein synthesis. From these interactions we determined that yeast strains lacking SCS3 and YFT2 are defective in their response to chronic ER stress and cannot induce the unfolded protein response pathway or transcription of phospholipid biosynthetic genes in low inositol. Our findings suggest that the mammalian FIT genes may play an important role in ER stress pathways, which are linked to obesity and type 2 diabetes.

Mining for future health care providers in Appalachian Kentucky

Recent studies project a significant shortage of U.S. health care providers within the next decade. To address southeastern Kentucky's persistent undersupply of medical professionals, a multi-county Health Career Enrichment Camp for rising 9th and 10th grade students was implemented in 2008. This report describes the annual camp's development and preliminary outcomes.

Re-patterning of skeletal muscle energy metabolism by fat storage-inducing transmembrane protein 2

Triacylglyceride stored in cytosolic lipid droplets (LDs) constitutes a major energy reservoir in most eukaryotes. The regulated turnover of triacylglyceride in LDs provides fatty acids for mitochondrial β-oxidation and ATP generation in physiological states of high demand for energy. The mechanisms for the formation of LDs in conditions of energy excess are not entirely understood. Fat storage-inducing transmembrane protein 2 (FIT2/FITM2) is the anciently conserved member of the fat storage-inducing transmembrane family of proteins implicated to be important in the formation of LDs, but its role in energy metabolism has not been tested. Here, we report that expression of FIT2 in mouse skeletal muscle had profound effects on muscle energy metabolism. Mice with skeletal muscle-specific overexpression of FIT2 (CKF2) had significantly increased intramyocellular triacylglyceride and complete protection from high fat diet-induced weight gain due to increased energy expenditure. Mass spectrometry-based metabolite profiling suggested that CKF2 skeletal muscle had increased oxidation of branched chain amino acids but decreased oxidation of fatty acids. Glucose was primarily utilized in CKF2 muscle for synthesis of the glycerol backbone of triacylglyceride and not for glycogen production. CKF2 muscle was ATP-deficient and had activated AMP kinase. Together, these studies indicate that FIT2 expression in skeletal muscle plays an unexpected function in regulating muscle energy metabolism and indicates an important role for lipid droplet formation in this process.

Structural insights into triglyceride storage mediated by fat storage-inducing transmembrane (FIT) protein 2

Fat storage-Inducing Transmembrane proteins 1 & 2 (FIT1/FITM1 and FIT2/FITM2) belong to a unique family of evolutionarily conserved proteins localized to the endoplasmic reticulum that are involved in triglyceride lipid droplet formation. FIT proteins have been shown to mediate the partitioning of cellular triglyceride into lipid droplets, but not triglyceride biosynthesis. FIT proteins do not share primary sequence homology with known proteins and no structural information is available to inform on the mechanism by which FIT proteins function. Here, we present the experimentally-solved topological models for FIT1 and FIT2 using N-glycosylation site mapping and indirect immunofluorescence techniques. These methods indicate that both proteins have six-transmembrane-domains with both N- and C-termini localized to the cytosol. Utilizing this model for structure-function analysis, we identified and characterized a gain-of-function mutant of FIT2 (FLL(157-9)AAA) in transmembrane domain 4 that markedly augmented the total number and mean size of lipid droplets. Using limited-trypsin proteolysis we determined that the FLL(157-9)AAA mutant has enhanced trypsin cleavage at K86 relative to wild-type FIT2, indicating a conformational change. Taken together, these studies indicate that FIT2 is a 6 transmembrane domain-containing protein whose conformation likely regulates its activity in mediating lipid droplet formation.

Effects of N-glycosylation on the activity and localization of GlcNAc-6-sulfotransferase 1

N-Acetylglucosamine-6-sulfotransferase-1 (GlcNAc6ST-1) is a Golgi-resident glycoprotein that is responsible for sulfation of the l-selectin ligand on endothelial cells. Here, we report the sites at which GlcNAc6ST-1 is modified with N-linked glycans and the effects that each glycan has on enzyme activity, specificity, and localization. We determined that glycans are added at three of four potential N-linked glycosylation sites: N196, N410, and N428. The N428 glycan is required for the production of sulfated cell surface glycans: cells expressing a mutant enzyme lacking this glycan were unable to sulfate the sialyl Lewis X tetrasaccharide or a putative extended core 1 O-linked glycan. The N196 and N410 glycans differentially affect sulfation of two different substrates: cells that express an enzyme lacking the N410 glycan are able to sulfate the sialyl Lewis X substrate, but produce reduced levels of a sulfated peripheral lymph node addressin epitope and cells that express an enzyme lacking the N196 glycan are able to produce a sulfated peripheral lymph node addressin epitope, but are impaired in their ability to sulfate sialyl Lewis X. The glycans' effects on enzyme activity may be mediated, in part, by changes in enzyme localization. While most mutants that lacked glycans localized normally within the Golgi, the N428A mutant and a mutant lacking all glycans were also found to localize ectopically. Altered trafficking of mutants may be associated with the mechanisms by which misglycosylated enzyme is degraded.

CD8 T Cell Responses to Myelin Oligodendrocyte Glycoprotein-Derived Peptides in Humanized HLA-A*0201-Transgenic Mice

Multiple sclerosis (MS) is a demyelinating inflammatory disease of the CNS. Though originally believed to be CD4-mediated, additional immune effector mechanisms, including myelin-specific CD8(+) T cells, are now proposed to participate in the pathophysiology of MS. To study the immunologic and encephalitogenic behavior of HLA-A*0201-binding myelin-derived epitopes in vivo, we used a humanized HLA-A*0201-transgenic mouse model. Eight HLA-A*0201-binding peptides derived from myelin oligodendrocyte glycoprotein (MOG), an immunodominant myelin self-Ag, were identified in silico. After establishing their relative affinity for HLA-A*0201 and their capacity to form stable complexes with HLA-A*0201 in vitro, their immunological characteristics were studied in HLA-A*0201-transgenic mice. Five MOG peptides, which bound stably to HLA-A*0201 exhibited strong immunogenicity by inducing a sizeable MOG-specific HLA-A*0201-restricted CD8(+) T cell response in vivo. Of these five candidate epitopes, four were processed by MOG-transfected RMA target cells and two peptides proved immunodominant in vivo in response to a plasmid-encoding native full-length MOG. One of the immunodominant MOG peptides (MOG(181)) generated a cytotoxic CD8(+) T cell response able to aggravate CD4(+)-mediated EAE. Therefore, this detailed in vivo characterization provides a hierarchy of candidate epitopes for MOG-specific CD8(+) T cell responses in HLA-A*0201 MS patients identifying the encephalitogenic MOG(181) epitope as a primary candidate.

Kentucky Homeplace Defeat Diabetes Screening Test: an analysis of rural Kentucky's challenge to overcome the growing diabetes epidemic

The University of Kentucky Center for Rural Health original research note, "Kentucky Homeplace Defeat Diabetes Screening Test: An Analysis of Rural Kentucky's Challenge to Overcome the Growing Diabetes Epidemic," provides the results of a yearlong diabetes risk survey that included more than 3,000 participants in rural Kentucky. It is well known that diabetes poses serious health threats across our country. For various reasons, that is especially true in Kentucky, with rural Kentucky having the highest prevalence for the disease. From September 2002 through August 2003, lay health workers with the nationally recognized Kentucky Homeplace program distributed and processed 3,092 diabetes self-test surveys to their clients across five regions of the state to get a better picture of the diabetes epidemic. The screening test was developed as an educational and public awareness tool by the Defeat Diabetes Foundation Inc, a nonprofit organization based in Madeira Beach, FL. It was distributed to various health agencies across the country. Each survey contained 16 questions, ranging from determining participants' urinary frequency and family medical history to their age and weight. Zero, five, or 10 points were allotted depending on respondents' degree of incidence for each question. A score of 0-15 points suggested a low risk for having diabetes, 20-25 points suggested that a respondent was at medium risk and should be tested for the disease, and a score of 30 points or higher suggested that he/she was at very high risk and "should seek (a) medical evaluation right away." Several months of analysis of the data collected indicated that 74.6% of the Kentucky Homeplace clients who participated in the survey were at moderate to significant risk of having or developing diabetes, a much higher rate than the approximately 50% of Kentucky adults in the general population that previous studies indicated were at risk. While findings from the survey of more than 3,000 Kentucky Homeplace clients cannot be generalized to Kentucky's population as a whole, they further confirm other evidence indicating that diabetes will continue to be one of the most serious health threats facing the state's rural populations. The research note further offered some recommendations for curbing rural Kentucky's diabetes epidemic, including increasing the number of certified diabetes educators serving rural Kentucky, expanding lay health worker programs within the rural portions of the Commonwealth, and studying the method and effectiveness of diabetes education between physicians and patients.

HLA-A*0201-restricted cytolytic responses to the rtTA transactivator dominant and cryptic epitopes compromise transgene expression induced by the tetracycline on system

The tetracycline-controlled transcription system (Tet-on) is widely used to regulate gene expression in mammalian cells. In gene therapy applications, immune responses to Tet-on proteins such as the rtTA transcription factor have been reported, raising concerns about their occurrence in humans. To monitor the HLA class I cytolytic responses against Tet-on regulators, we characterized the immunogenic CD8+ epitopes within rtTA and tTS regulators using HLA-A*0201 class I transgenic mice. Epitope prediction programs, HLA-A*0201 binding assays, and peptide immunization were used to select a set of immunogenic peptides within rtTA and tTS sequences. To identify further the rejection epitopes, we expressed Tet-on protein components in vivo and found a single dominant rtTA186 CTL epitope in the rtTA tetracycline repressor domain. Target cells expressing rtTA were susceptible to CTL lysis, and rtTA expression compromised muscle transgene engraftment. To reduce the occurrence of immune responses to rtTA protein, we mutated the dominant rtTA186 epitope and found that this leads to the appearance of subdominant epitopes. As a result, we think that an epitope modification strategy is not applicable to blunt the immune response in this model. Moreover, the identification of HLA-A*0201 rtTA epitopes allowed us to demonstrate here that the delivery of the Tet-on system with weakly immunogenic rAAV vectors does not trigger primary CTL responses in mice, in contrast to DNA transfer. Altogether, the existence of HLA-A*0201 rtTA epitopes may lead to the occurrence of immune responses depending on vectors and local inflammation in gene therapy applications involving rtTA-based regulatory systems.

[Anchoring cytokines to cancer cells using diphtheria toxin: better than immunotherapy by gene transfer?]

Many cytokines are able to stimulate the antitumor immune response. However, in order to avoid the toxic effects due to systemic injection, it is necessary to concentrate the cytokines in the tumor microenvironment. Current methods, based on the transfer of cytokine genes into tumor cells, still suffer drawbacks. We describe an alternative approach using recombinant cytokines genetically conjugated to a membrane anchor derived from diphtheria toxin. Interleukin-2 anchored to lymphoma and melanoma cells remained displayed on their surface and were not internalized. Injection of these cell preparations to mice led to an immune response able to prevent or slow tumor growth following tumor challenge.

Identification of HER-2/neu immunogenic epitopes presented by renal cell carcinoma and other human epithelial tumors

HER-2/neu is a tumor-associated antigen overexpressed in a large variety of human tumors. Eight HER-2/neu peptides displaying HLA-A*0201 anchoring motifs were selected and tested for their binding affinity to HLA-A*0201 and their capacity to elicit cytotoxic T lymphocyte (CTL) responses in both HLA-A*0201 transgenic mice and in HLA-A*0201(+) healthy donors. Two high-affinity (p5 and p48) and one intermediate-affinity (p1023) peptides triggered CTL responses in both transgenic mice and humans, comparable to those observed for the well-known HER2/neu dominant peptide p369. CTL induced in transgenic mice lysed HLA-A*0201(+) RMA cells infected with recombinant HER-2/neu but not cells infected with wild-type vaccinia virus. Human CTL lysed HLA-A*0201(+) HER-2/neu(+) tumor cells of different origins (breast, colon, lung and renal cancer) irrespective of the expression levels of HER-2/neu. Importantly, primed CTL specific for these epitopes were detected in freshly isolated tumor-infiltrating lymphocytes from three renal cell carcinoma patients. Therefore, the HER-2/neu peptides p5, p48 and p1023 may be good candidates for immunotherapy of a broad spectrum of tumors, including renal cell carcinoma.

A skin surgery fable

A fable is presented to inform the reader of the existence of a valuable, but under-utilized educational resource that might be utilized in the teaching of dermatologic surgery.

A general strategy to enhance immunogenicity of low-affinity HLA-A2. 1-associated peptides: implication in the identification of cryptic tumor epitopes

Low-affinity MHC class I-associated cryptic epitopes derived from self proteins overexpressed in a wide variety of human tumors or derived from antigens of viruses exhibiting a high mutation rate, could be interesting candidates for tumor and virus immunotherapy, respectively. However, identification of low-affinity MHC-associated epitopes comes up against their poor immunogenicity. Here we describe an approach that enhances immunogenicity of nonimmunogenic low-affinity HLA-A2.1-binding peptides. It consists of modifying their sequence by introducing a tyrosine in the first position (P1Y). P1Y substitution enhances affinity of HLA-A2.1-associated peptides without altering their antigenic specificity. In fact, P1Y variants of ten nonimmunogenic low-affinity peptides exhibited a 2.3- to 55-fold higher binding affinity and/or stabilized the HLA-A2.1 for at least 2 h more than the corresponding native peptides. More importantly, P1Y variants efficiently triggered in vivo native peptide-specific CTL which also recognized the corresponding naturally processed epitope. The possibility for generating CTL against any low-affinity HLA-A2.1-associated peptide provides us with the necessary tool for the identification of cryptic tumor and virus epitopes which could be used for peptide-based immunotherapy.

Clinical and genetic heterogeneity in familial focal segmental glomerulosclerosis. International Collaborative Group for the Study of Familial Focal Segmental Glomerulosclerosis

BACKGROUND

Familial forms of focal segmental glomerulosclerosis (FFSGS) that exhibit autosomal dominant or recessive patterns of inheritance have been described. The genetic basis of these hereditary forms of FSGS is unknown. One recent study of a kindred from Oklahoma with an autosomal dominant form of FSGS linked this disease to a region of chromosome 19q. In addition, polymorphisms in a gene in this region on chromosome 19q13 have been linked to congenital nephrotic syndrome of the Finnish type. We have ascertained and characterized a large family with autosomal dominant FFSGS (Duke 6530).

METHODS

Families were compared for clinical and genetic heterogeneity. To test for linkage of our family to this portion of chromosome 19, genomic DNA was isolated from 102 family members, and polymerase chain reaction was performed using eight microsatellite markers that spanned the area of interest on chromosome 19. Data were evaluated using two-point linkage analysis, multipoint analysis, and an admixture test.

RESULTS

Linkage was excluded at a distance of +/- 5 to 10 CM for all markers tested with two-point log10 of the odds of linkage (LOD) scores and from an approximate 60 CM interval in this area of chromosome 19q via multipoint analysis.

CONCLUSIONS

FSGS has been called the "final common pathway" of glomerular injury, as it is a frequent pathological manifestation with diverse etiologies. This diversity likely correlates with the genetic heterogeneity that we have established. Thus, our data demonstrate that there are at least two genes responsible for this disease, and there is genetic as well as clinical heterogeneity in autosomal dominant FSGS.

Patient satisfaction with time spent with their physician

BACKGROUND

We examined the variables related to patient satisfaction with the time spent with their family physician during the office visit.

METHODS

Research nurses directly observed consecutive patient visits to 138 family physicians in 84 practices. Analyses examined sequential models of the association of patient and physician characteristics, visit type and length, and time use during visits, with patients' satisfaction with the amount of time spent with their physician.

RESULTS

Among 2315 visit by adult patients returning questionnaires, patient satisfaction with the time spent with their physician was high and strongly linked to longer visits (P < 001). After controlling for visit duration, greater patient satisfaction with time spent was associated with older patient age, white race, better perceived health status, visits for well care, and visits with a greater proportion of the visit spent chatting. The physician's discussion of test results or findings from the physical examination was associated with greater satisfaction with time spent for visits longer than 15 minutes, but with less satisfaction with time spent for shorter visits.

CONCLUSIONS

Physicians can enhance patient satisfaction with the amount of time spent during an office visit by spending a small proportion of time chatting about nonmedical topics, and by allowing sufficient time for exchange with the patient is feedback is necessary.

Gonadal steroidogenesis in vitro from juvenile alligators obtained from contaminated or control lakes

The ubiquitous distribution of many contaminants and the nonlethal, multigenerational effects of such contaminants on reproductive, endocrine, and immune systems have led to concerns that wildlife worldwide are affected. Although the causal agents and effects are known for some species, the underlying physiological mechanisms associated with contaminant-induced reproductive modifications are still poorly understood and require extensive research. We describe a study examining the steroidogenic activity of gonads removed from juvenile alligators (Alligator mississippiensis) obtained from contaminated or control lakes in central Florida. Synthesis of estradiol-17 beta (E2) was significantly different when ovaries from the contaminated and control lakes were compared in vitro. Additionally, testes from males obtained from the contaminated lake. Lake Apopka, synthesized significantly higher concentrations of E2 when compared to testes obtained from control males. In contrast, testosterone (T) synthesis from all testes examined in this study displayed a normal pattern and produced concentrations greater than that observed from ovaries obtained from either lake. Interestingly, the pattern of gonadal steroidogenesis differs from previously reported plasma concentrations of these hormones obtained from the same individuals. We suggest that the differences between the in vivo and in vitro patterns are due to modifications in the hepatic degradation of plasma sex steroid hormones.

The vertical wedge biopsy

A biopsy technique is described that has been used in my clinical practice thousands of times. This very simple, cost-effective technique employs only one surgical tool, the scalpel blade, and permits a biopsy to be taken with sufficient tissue for histologic analysis. In that there is no disruption of a tumor margin, it permits the physician to make a diagnosis and not limit his or her choice of therapeutic modalities. Again, I wish to stress that appropriate selection of lesions is a critical point of this technique. It is unacceptable for lesions suspected to be malignant melanoma or for dermatoses that may have a deep component.

Cooperative frozen section surgery

Utilization of the office setting for frozen section evaluation of tumor removal in the treatment of skin cancer is of considerable value. The impact of such surgery includes (1) enhanced quality of surgery by reducing the possibility of incomplete removal of tumor, (2) decreased financial cost to the patient when compared to hospital treatment, (3) better utilization of the doctor's time and facilities, (4) decreased disruption in the life of the patient and his family in terms of time off from work, surgery schedule flexibility, and a decrease in patient anxiety.

On history-taking before surgery

History-taking is discussed with particular reference to cutaneous surgery. Systematic questioning with regard to general health, established and potential allergies, medicaments currently being taken, and miscellaneous relevant matters is important to the planning, execution, and outcome of surgical procedures.

Medical origins of psychiatric emergencies: the systems approach

Nowhere else in the discipline of Psychiatry is the use of medical model differential diagnosis more relevant than in the evaluation of the psychiatric emergency. This article discusses the psycho-physiological states that present clinically as psychiatric emergencies.