ABSTRACT
Malaria vector surveillance tools often incorporate features of hosts that are attractive to blood-seeking females. The recently developed host decoy trap (HDT) combines visual, thermal, and olfactory stimuli associated with human hosts and has shown great efficacy in terms of collecting malaria vectors. Synthetic odors and yeast-produced carbon dioxide (CO2) could prove useful by mimicking the human odors currently used in HDTs and provide standardized and easy-to-use olfactory attractants. The objective of this study was to test the attractiveness of various olfactory attractant cues in HDTs to capture malaria vectors. We compared 4 different odor treatments in outdoor field settings in southern Benin and western Burkina Faso: the standard HDT using a human, HDT with yeast-produced CO2, HDT with an artificial odor blend, and HDT with yeast-produced CO2 plus artificial odor blend. In both experimental sites, the standard HDT that incorporated a real human produced the greatest catch of Anopheles gambiae s.l (Diptera: Culicidae). The alternatives tested were still effective at collecting target vector species, although the most effective included CO2, either alone (Benin) or in combination with synthetic odor (Burkina Faso). The trap using synthetic human odor alone caught the fewest An. gambiae s.l. compared to the other baited traps. Both Anopheles coluzzii and Anopheles gambiae were caught by each trap, with a predominance of An. coluzzii. Synthetic baits could, therefore, represent a more standardized and easier-to-deploy approach than using real human odor baits for a robust vector monitoring strategy.
Subject(s)
Anopheles , Mosquito Control , Mosquito Vectors , Odorants , Animals , Anopheles/physiology , Burkina Faso , Mosquito Vectors/physiology , Mosquito Control/methods , Female , Humans , Benin , Malaria/transmission , Malaria/prevention & control , Carbon DioxideABSTRACT
Approaching disease elimination, it is crucial to be able to assess progress towards key objectives using quantitative tools. For Gambian human African trypanosomiasis (HAT), the ultimate goal is to stop transmission by 2030, while intermediary targets include elimination as a public health problem - defined as <1 new case per 10,000 inhabitants in 90% of foci, and <2000 reported cases by 2020. Using two independent mathematical models, this study assessed the achievability of these goals in the former Equateur province of the Democratic Republic of Congo, which historically had endemic levels of disease. The two deterministic models used different assumptions on disease progression, risk of infection and non-participation in screening, reflecting biological uncertainty. To validate the models a censor-fit-uncensor procedure was used to fit to health-zone level data from 2000 to 2012; initially the last six years were censored, then three and the final step utilised all data. The different model projections were used to evaluate the expected transmission and reporting for each health zone within each province under six intervention strategies using currently available tools. In 2012 there were 197 reported HAT cases in former Equateur reduced from 6828 in 2000, however this reflects lower active testing for HAT (1.3% of the population compared to 7.2%). Modelling results indicate that there are likely to be <300 reported cases in former Equateur in 2020 if screening continues at the mean level for 2000-2012 (6.2%), and <120 cases if vector control is introduced. Some health zones may fail to achieve <1 new case per 10,000 by 2020 without vector control, although most appear on track for this target using medical interventions alone. The full elimination goal will be harder to reach; between 39 and 54% of health zones analysed may have to improve their current medical-only strategy to stop transmission completely by 2030.
Subject(s)
Disease Eradication , Models, Theoretical , Trypanosomiasis, African/epidemiology , Trypanosomiasis, African/prevention & control , Congo/epidemiology , Humans , Reproducibility of Results , Trypanosomiasis, African/transmissionSubject(s)
Nuchal Translucency Measurement , Pregnancy, Twin/genetics , Twins, Monozygotic/genetics , Adult , Chorionic Villi Sampling , Chromosome Deletion , Chromosomes, Human, Pair 7 , Crown-Rump Length , Female , Fetal Heart/abnormalities , Fetal Heart/diagnostic imaging , Fetofetal Transfusion , Humans , Karyotyping , Pregnancy , Pregnancy Reduction, MultifetalABSTRACT
The leishmaniases comprise a complex of diseases characterized by clinical outcomes that range from self-limiting to chronic, and disfiguring and stigmatizing to life threatening. Diagnostic methods, treatments, and vector and reservoir control options exist, but deciding the most effective interventions requires a quantitative understanding of the population level infection and disease dynamics. The effectiveness of any set of interventions has to be determined within the context of operational conditions, including economic and political commitment. Mathematical models are the best available tools for studying quantitative systems crossing disciplinary spheres (biology, medicine, economics) within environmental and societal constraints. In 2005, the World Health Assembly and government health ministers of India, Nepal, and Bangladesh signed a Memorandum of Understanding to eliminate the life threatening form of leishmaniasis, visceral leishmaniasis (VL), on the Indian subcontinent by 2015 through a combination of early case detection, improved treatments, and vector control. The elimination target is <1 case/10,000 population at the district or subdistrict level compared to the current 20/10,000 in the regions of highest transmission. Towards this goal, this chapter focuses on mathematical models of VL, and the biology driving those models, to enable realistic predictions of the best combination of interventions. Several key issues will be discussed which have affected previous modelling of VL and the direction future modelling may take. Current understanding of the natural history of disease, immunity (and loss of immunity), and stages of infection and their durations are considered particularly for humans, and also for dogs. Asymptomatic and clinical infection are discussed in the context of their relative roles in Leishmania transmission, as well as key components of the parasite-sandfly-vector interaction and intervention strategies including diagnosis, treatment and vector control. Gaps in current biological knowledge and potential avenues to improve model structures and mathematical predictions are identified. Underpinning the marriage between biology and mathematical modelling, the content of this chapter represents the first step towards developing the next generation of models for VL.
Subject(s)
Dog Diseases/transmission , Insect Vectors/parasitology , Leishmania donovani/physiology , Leishmaniasis, Visceral/transmission , Models, Theoretical , Psychodidae/parasitology , Animals , Dog Diseases/parasitology , Dog Diseases/prevention & control , Dogs , Humans , Leishmaniasis, Visceral/parasitology , Leishmaniasis, Visceral/prevention & control , Neglected DiseasesABSTRACT
The biology and behaviour of biting insects is a vitally important aspect in the spread of vector-borne diseases. This paper aims to determine, through the use of mathematical models, what effect incorporating vector senescence and realistic feeding patterns has on disease. A novel model is developed to enable the effects of age- and bite-structure to be examined in detail. This original PDE framework extends previous age-structured models into a further dimension to give a new insight into the role of vector biting and its interaction with vector mortality and spread of disease. Through the PDE model, the roles of the vector death and bite rates are examined in a way which is impossible under the traditional ODE formulation. It is demonstrated that incorporating more realistic functions for vector biting and mortality in a model may give rise to different dynamics than those seen under a more simple ODE formulation. The numerical results indicate that the efficacy of control methods that increase vector mortality may not be as great as predicted under a standard host-vector model, whereas other controls including treatment of humans may be more effective than previously thought.
Subject(s)
Insect Vectors/physiology , Models, Biological , Age Factors , Animals , Bites and Stings , Feeding Behavior/physiology , Humans , Longevity , Models, TheoreticalABSTRACT
Hyaluronan (HA) is responsive to pro-atherosclerotic growth factors and cytokines and is thought to contribute to neointimal hyperplasia and atherosclerosis. However, the specific function of the pericellular HA matrix is likely depend on the respective stimuli. Adenosine plays an important role in the phenotypic regulation of vascular smooth muscle cells (VSMC) and is thought to inhibit inflammatory responses during atherosclerosis. The aim of this study was to examine the regulation and function of HA matrix in response to adenosine in human coronary artery SMC (HCASMC). The adenosine receptor agonist NECA (10 µM) caused a strong induction of HA synthase (HAS)1 at 6 h and a weaker induction again after 24 h. Use of selective adenosine receptor antagonists revealed that adenosine A2(B) receptors (A2(B)R) mediate the early HAS1 induction, whereas late HAS1 induction was mediated via A2(A)R and A3R. The strong response after 6 h was mediated in part via phosphoinositide-3 kinase- and mitogen-activated protein kinase pathways and was inhibited by Epac. Functionally, NECA increased cell migration, which was abolished by shRNA-mediated knock down of HAS1. In addition to HA secretion, NECA also stimulated the formation of pronounced pericellular HA matrix in HCASMC and increased the adhesion of monocytes. The adenosine-induced monocyte adhesion was sensitive to hyaluronidase. In conclusion, the current data suggest that adenosine via adenosine A2(B)R and A2(A)R/A3R induces HAS1. In turn a HA-rich matrix is formed by HCASMC which likely supports the migratory HCASMC phenotype and traps monocytes/macrophages in the interstitial matrix.
Subject(s)
Adenosine/pharmacology , Atherosclerosis/metabolism , Coronary Vessels/drug effects , Hyaluronic Acid/metabolism , Muscle, Smooth, Vascular/drug effects , Adenosine-5'-(N-ethylcarboxamide)/pharmacology , Cell Adhesion , Cell Movement , Cell Proliferation , Cells, Cultured , Coronary Vessels/metabolism , DNA Primers/chemistry , Gene Expression Regulation , Glucuronosyltransferase/genetics , Glucuronosyltransferase/metabolism , Humans , Hyaluronan Synthases , Monocytes/metabolism , Muscle, Smooth, Vascular/metabolism , RNA, Messenger/drug effects , RNA, Messenger/metabolism , Real-Time Polymerase Chain Reaction , Receptor, Adenosine A3/metabolism , Receptors, Adenosine A2/metabolism , Receptors, Purinergic/metabolism , Signal Transduction/physiology , Vasodilator Agents/pharmacologyABSTRACT
OBJECTIVE: Glioblastoma multiforme (GBM) accounts for up to 60% of all malignant primary brain tumours in adults, occurring in 2-3 cases per 100,000 in Europe and North America. In 2005, a Phase III clinical trial demonstrated a significant improvement in survival over 2, and subsequently 5, years with the addition of concurrent and adjuvant temozolomide (TMZ) to radical radiotherapy (RT). The aim of this study was to investigate if the demonstrated improved survival in the literature translated to clinical practice. METHODS: This was a retrospective study including all patients with histologically proven GBM diagnosed from 1999 to 2008 and treated with adjuvant RT at our institution. A total of 273 patients were identified. Statistical analysis was carried out using SPSS® v.18 (SPSS, Chicago, IL). RESULTS: The median survival for the whole group (n=273) over the 10-year period was 7.6 months (95% confidence interval 6.7-8.4 months). Overall, the cumulative probability of survival at 1 and 2 years was 31.5% and 9.4%, respectively. In total, 146 patients received radical RT. 103 patients were treated with radical RT and TMZ and 43 patients received radical RT alone. The median survival for patients receiving radical RT with TMZ was 13.4 months (95% CI 10.9-15.8 months) vs 8.8 months for radical RT alone (95% CI 6.9-10.7 months, p=0.006). 2-year survival figures were 21.2% vs 4.7%, respectively. On multivariate analysis, independent predictors of survival included Karnofsky Performance Status, RT dose, TMZ and extent of surgery. The strongest predictors of poorer outcome based on the hazard ratio were palliative RT, followed by not receiving TMZ chemotherapy, then KPS <90 and a biopsy only surgical approach. CONCLUSION: This paper demonstrates improved survival outcomes consistent with those published in the literature for the addition of concurrent and adjuvant TMZ to radical RT for the treatment of GBM. Although 63% of patients seen in the clinic were suitable for a combined modality approach, the prognosis for the lower Radiation Therapy Oncology Group classes still remains poor.
Subject(s)
Brain Neoplasms/mortality , Brain Neoplasms/therapy , Chemoradiotherapy, Adjuvant/mortality , Dacarbazine/analogs & derivatives , Glioblastoma/mortality , Glioblastoma/therapy , Radiotherapy, Conformal/mortality , Adult , Aged , Antineoplastic Agents, Alkylating/therapeutic use , Dacarbazine/therapeutic use , Female , Humans , Ireland/epidemiology , Male , Middle Aged , Prevalence , Survival Analysis , Survival Rate , Temozolomide , Treatment Outcome , Young AdultABSTRACT
The objective of this study was to evaluate if transrectal optical tomography implemented at three wavelength bands for spectral detection could monitor changes of the hemoglobin oxygen saturation (StO2) in addition to those of the total hemoglobin concentration ([HbT]) in lesions of a canine prostate, including an induced tumor modeling canine prostate cancer. Near-infrared (NIR) optical tomography was integrated with ultrasound (US) for transrectal imaging. Multi-spectral detection at 705_nm, 785_nm and 808_nm rendered measurements of [HbT] and StO2. Canine transmissible venereal tumor (TVT) cells were injected into the right lobe of a dog's prostate gland, which had a pre-existing cyst in the left lobe. Longitudinal assessments of the prostate were performed weekly over a 63-day duration by NIR imaging concurrent with grey-scale and Doppler US. Ultrasonography revealed a bi-lobular tumor-mass regressing from day-49 to day-63. At day-49 this tumor-mass developed a hypoxic core that became larger and more intense by day-56 and expanded further by day-63. The tumor-mass presented a strong hyper-[HbT] feature on day-56 that was inconsistent with US-visualized blood flow. Histology confirmed two necrotic TVT foci within this tumor-mass. The cyst appeared to have a large anoxic-like interior that was greater in size than its ultrasonographically delineated lesion, and a weak lesional elevation of [HbT]. On day-56, the cyst presented a strong hyper-[HbT] feature consistent with US-resolved blood flow. Histology revealed acute and chronic hemorrhage in the periphery of the cyst. The NIR imaging features of two other TVT nodules and a metastatic lymph node were evaluated retrospectively. Transrectal US-integrated spectral optical tomography seems to enable longitudinal monitoring of intra-lesional oxygenation dynamics in addition to the hemoglobin content of lesions in the canine prostate.
Subject(s)
Hypoxia , Prostate/diagnostic imaging , Prostatic Neoplasms/diagnostic imaging , Tomography, Optical/instrumentation , Tomography, Optical/methods , Venereal Tumors, Veterinary/diagnostic imaging , Venereal Tumors, Veterinary/pathology , Algorithms , Animals , Computer Simulation , Dogs , Male , Mice , Mice, Inbred NOD , Mice, SCID , Spectroscopy, Near-Infrared , UltrasonographyABSTRACT
Photoaged skin is clinically characterized by wrinkling, laxity and a leather-like appearance. These symptoms of actinic aging are causally connected to histological and ultrastructural changes of the connective tissue of the dermis. Changes include both enzymatic degradation and reduced de novo synthesis of collagen which cause premature wrinkling of the skin. Changes in the hyaluronan and proteoglycan matrix lead to reduced water content and thereby increased laxity of the skin. Furthermore, the UV-induced remodeling of the extracellular matrix strongly affects the cellular phenotypes such as the regenerative capacity of dermal fibroblasts. In recent years considerable progress has been made towards the understanding of molecular and cellular mechanisms underlying the UV-induced changes of the extracellular matrix. Current findings in this field reveal interesting insights in the dermal aging and provide new targets and strategies for the treatment of photoaging.
Subject(s)
Extracellular Matrix/physiology , Extracellular Matrix/radiation effects , Skin Aging/physiology , Skin Aging/radiation effects , Sunlight/adverse effects , Ultraviolet Rays/adverse effects , Animals , Collagen/metabolism , Elastin/metabolism , Fibroblasts/physiology , Fibroblasts/radiation effects , Humans , Hyaluronic Acid/metabolism , Proteoglycans/metabolism , Regeneration/physiology , Regeneration/radiation effectsABSTRACT
BACKGROUND AND PURPOSE: Cyclooxygenase-2 (COX2) and hyaluronic acid (HA) are common in tumours and both independently promote tumour progression. Furthermore, COX2-dependent synthesis of prostaglandins (PGs) stimulates HA synthase-1 (HAS1) and HAS2 mRNA expression, together with HA synthesis via the cAMP/protein kinase A pathway in vascular smooth muscle cells. Therefore, the aim of the present study was to elucidate whether COX2-mediated PGs induce transcription of HAS isoforms in cancer cells as well. EXPERIMENTAL APPROACH: Human oesophageal squamous cell (OSC) carcinoma specimens were characterized with respect to HA, COX2 and CD44 expression by immunohistochemistry. OSC cell lines (OSC1, OSC2) and HeLa cell lines (D98, H21) were exposed to exogenous PG analoques (100 nmol.L(-1)), etoricoxib (10 micromol.L(-1)) and forskolin (10 micromol.L(-1)). Subsequently, cAMP levels, HA secretion and HAS isoform expression were determined by elisa and real-time RT-PCR (reverse transcriptase polymerase chain reaction) respectively. KEY RESULTS: COX2, HA and CD44 were detected immunohistochemically in >90% of human oesophageal tumour samples. Under basal conditions, OSC1 and OSC2 cells express HAS2 and HAS3, COX2 and Galpha(s)-coupled EP(2) and EP(4) PG receptors. Neither stimulation with the PGI(2) analogue, iloprost, addition of exogenous PGE(2) nor forskolin induced HAS1 or HAS2 mRNA expression in OSC1 and OSC2 cells. Furthermore, in HeLa cells after induction of COX2 by tumour necrosis factor alpha and subsequent PGE(2) release, inhibition of COX2 by etoricoxib did not affect HAS expression or HA secretion. CONCLUSIONS AND IMPLICATIONS: We conclude that in oesophageal and HeLa cancer cells, HAS1/2 expression was not responsive to the PG/cAMP pathway.
Subject(s)
Carcinoma, Squamous Cell/metabolism , Cyclic AMP/metabolism , Esophageal Neoplasms/metabolism , Hyaluronic Acid/biosynthesis , Prostaglandins/metabolism , Base Sequence , Carcinoma, Squamous Cell/enzymology , Carcinoma, Squamous Cell/pathology , Cell Line, Tumor , Cyclooxygenase 2/metabolism , DNA Primers , Esophageal Neoplasms/enzymology , Esophageal Neoplasms/pathology , Humans , Immunohistochemistry , Reverse Transcriptase Polymerase Chain ReactionABSTRACT
AIM: To test whether alpha-methylacyl-CoA racemase (AMACR) is a sensitive and specific marker of prostate cancer. METHODS AND RESULTS: The expression levels of AMACR mRNA were measured by real-time polymerase chain reaction. A total of 807 prostatic specimens were further examined by immunohistochemistry specific for AMACR. Quantitative immunostaining analyses were carried out by using the ChromaVision Automated Cellular Imaging System and the Ariol SL-50 Imaging System, respectively. AMACR mRNA levels measured in prostatic adenocarcinoma were 55 times higher than those in benign prostate tissue. Of 454 cases of prostatic adenocarcinoma, 441 were positive for AMACR, while 254 of 277 cases of benign prostate were negative for AMACR. The sensitivity and specificity of AMACR immunodetection of prostatic adenocarcinomas were 97% and 92%, respectively. Both positive and negative predictive values were 95%. By automatic imaging analyses, the AMACR immunostaining intensity and percentage in prostatic adenocarcinomas were also significantly higher than those in benign prostatic tissue (105.9 versus 16.1 for intensity, 45.7% versus 0.02% and 35.03% versus 4.64% for percentage, respectively). CONCLUSIONS: We have demonstrated the promising features of AMACR as a biomarker for prostate cancer in this large series and the potential to develop automated quantitative diagnostic tests.
Subject(s)
Biomarkers, Tumor/genetics , Prostatic Neoplasms/pathology , Racemases and Epimerases/genetics , Adenocarcinoma/enzymology , Adenocarcinoma/genetics , Adenocarcinoma/pathology , Biomarkers, Tumor/analysis , Humans , Immunohistochemistry , Male , Prostatic Neoplasms/enzymology , Prostatic Neoplasms/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism , Racemases and Epimerases/analysis , Reverse Transcriptase Polymerase Chain ReactionSubject(s)
Acetates/therapeutic use , Amines , Analgesics/therapeutic use , Cyclohexanecarboxylic Acids , Diabetic Neuropathies/complications , Pain/drug therapy , Pain/etiology , gamma-Aminobutyric Acid , Acetates/economics , Acetates/pharmacology , Analgesics/economics , Analgesics/pharmacology , Dose-Response Relationship, Drug , Drug Costs , Gabapentin , Humans , Pain/diagnosis , Pain Measurement , Patient Selection , Treatment OutcomeABSTRACT
The ability to diagnose prostate carcinoma would be improved by the detection of a tumor-associated antigen. P504S, a cytoplasmic protein, was recently identified by cDNA library subtraction in conjunction with high throughput microarray screening from prostate carcinoma. The aim of this study was to establish the pattern of expression of P504S in prostate carcinoma and benign prostatic tissue. A total of 207 cases, including 137 cases of prostate carcinoma and 70 cases of benign prostate, from prostatectomies (n = 77), prostate needle biopsies (n = 112), and transurethral prostate resections (n = 18) were examined by immunocytochemistry for P504S. P504S showed strong cytoplasmic granular staining in 100% of prostate carcinomas regardless of Gleason scores and diffuse (>75% of tumor) staining in 92% of cases. In contrast, 171 of 194 (88%) of benign prostates, including 56 of 67 (84%) benign prostate cases and 115 of 127 (91%) cases of benign glands adjacent to cancers were negative for P504S. The remainders of benign prostates were focally and weakly positive for P504S. The staining pattern of these normal glands was different and easily distinguishable from that observed in prostate carcinoma. Expression of P504S was not found in basal cell hyperplasia, urothelial cells/metaplasia and small atrophic glands that may mimic prostate carcinoma. Our findings indicate that P504S is a highly sensitive and specific positive marker for prostate carcinoma.
Subject(s)
Biomarkers, Tumor , Carcinoma/diagnosis , Prostatic Neoplasms/diagnosis , Racemases and Epimerases , Antibodies, Monoclonal , Blotting, Western , Carcinoma/enzymology , Carcinoma/surgery , Humans , Immunoenzyme Techniques , Keratins/metabolism , Male , Molecular Weight , Prostate/enzymology , Prostate/pathology , Prostate/surgery , Prostatic Neoplasms/enzymology , Prostatic Neoplasms/surgery , Racemases and Epimerases/metabolismABSTRACT
Nearly all peptides generated by proteasomes during protein degradation are digested rapidly to amino acids, but a few proteasomal products escape this fate and are presented to the immune system on cell surface major histocompatibility complex class I molecules. To test whether these antigenic peptides may be inherently resistant to cytosolic peptidases, six different antigenic peptides were incubated with HeLa cell extracts. All six were degraded rapidly by a process involving o-phenanthroline-sensitive metallopeptidases. One antigenic peptide, FAPGNYPAL, was rapidly destroyed in the extracts by a bestatin-sensitive exopeptidase, apparently by the puromycin-sensitive aminopeptidase. The disappearance of the other five was reduced 30-90% by a specific inhibitor of the cytosolic endopeptidase, thimet oligopeptidase (TOP) (EC ), whose physiological function(s) have been unclear and controversial. All these peptides were sensitive to pure recombinant TOP. Furthermore, upon fractionation of the extracts, the major peptidase peak that degraded the ovalbumin-derived epitope, SIINFEKL, co-purified with TOP. In the extracts, TOP also catalyzed rapid degradation of N-extended variants of SIINFEKL and of other antigenic peptides, which in vivo can serve as precursors of these major histocompatibility complex-presented epitopes. This enzyme (unlike cell proteins that promote production of antigenic peptides) is not regulated by interferon-gamma. TOP seems to be primarily responsible for the rapid breakdown of antigenic peptides in cytosolic extracts, and our related studies (A. X. Y. Mo, K. Lemerise, W. Zeng, Y. Shen, C. R. Abraham, A. L. Goldberg, and K. L. Rock, submitted for publication) indicate that TOP by destroying such peptides limits antigen presentation in vivo.
Subject(s)
Antigens/chemistry , Genes, MHC Class I , Major Histocompatibility Complex , Metalloendopeptidases/chemistry , Peptides/chemistry , Amino Acids/chemistry , Antigen Presentation , Catalysis , Chromatography, High Pressure Liquid , HeLa Cells , Humans , Immunoblotting , Interferon-gamma/chemistry , Leucine/analogs & derivatives , Leucine/pharmacology , Protease Inhibitors/pharmacology , Protein Structure, Tertiary , Protein Synthesis Inhibitors/pharmacology , Puromycin/pharmacology , Recombinant Proteins/chemistry , Recombinant Proteins/metabolism , Time FactorsABSTRACT
Protein degradation by proteasomes is the source of most antigenic peptides presented on MHC class I molecules. To determine whether proteasomes generate these peptides directly or longer precursors, we developed new methods to measure the efficiency with which 26S and 20S particles, during degradation of a protein, generate the presented epitope or potential precursors. Breakdown of ovalbumin by the 26S and 20S proteasomes yielded the immunodominant peptide SIINFEKL, but produced primarily variants containing 1-7 additional N-terminal residues. Only 6-8% of the times that ovalbumin molecules were digested was a SIINFEKL or an N-extended version produced. Surprisingly, immunoproteasomes which contain the interferon-gamma-induced beta-subunits and are more efficient in antigen presentation, produced no more SIINFEKL than proteasomes. However, the immunoproteasomes released 2-4 times more of certain N-extended versions. These observations show that the changes in cleavage specificity of immunoproteasomes influence not only the C-terminus, but also the N-terminus of potential antigenic peptides, and suggest that most MHC-presented peptides result from N-terminal trimming of larger proteasome products by aminopeptidases (e.g. the interferon-gamma-induced enzyme leucine aminopeptidase).
Subject(s)
Antigens/biosynthesis , Egg Proteins/biosynthesis , Epitopes, B-Lymphocyte/biosynthesis , Immunodominant Epitopes/biosynthesis , Ovalbumin/biosynthesis , Peptide Biosynthesis , Peptide Hydrolases/metabolism , Proteasome Endopeptidase Complex , Animals , Antigens/immunology , Egg Proteins/immunology , Epitopes, B-Lymphocyte/immunology , Hybridomas , Immunodominant Epitopes/immunology , Mice , Ovalbumin/immunology , Peptide Fragments , Peptides/immunologyABSTRACT
The finding that MHC class I molecules are physically associated with the TAP transporter has suggested that peptides may be directly transported into the binding groove of the class I molecules rather than into the lumen of the endoplasmic reticulum (ER) where they subsequently would encounter class I molecules by diffusion. Such a mechanism would protect peptides from peptidases in the ER and/or escaping back into the cytoplasm. However, we find that an anti-peptide Ab that is cotranslationally transported into the ER prevents TAP-transported peptides from being presented on class I molecules. The Ab only blocks the binding of its cognate peptide (SIINFEKL) but not other peptides (KVVRFKDL, ASNENMETM, and FAPGNYPAL). Therefore, most TAP-transported peptides must diffuse through the lumen of the ER before binding stably to MHC class I molecules.
Subject(s)
Antibodies, Blocking/pharmacology , Antibodies, Monoclonal/pharmacology , Endoplasmic Reticulum/immunology , Endoplasmic Reticulum/metabolism , H-2 Antigens/metabolism , Peptide Fragments/immunology , Peptide Fragments/metabolism , ATP-Binding Cassette Transporters/metabolism , Animals , Antibodies, Blocking/biosynthesis , Antibodies, Blocking/metabolism , Antibodies, Monoclonal/biosynthesis , Antibodies, Monoclonal/metabolism , Antigen Presentation , B-Lymphocytes/immunology , B-Lymphocytes/metabolism , Binding Sites, Antibody , Binding, Competitive/immunology , Cell Line , Diffusion , Egg Proteins/immunology , Egg Proteins/metabolism , Female , Hybridomas , Mice , Mice, Inbred C57BL , Ovalbumin/immunology , Ovalbumin/metabolism , Tumor Cells, CulturedABSTRACT
No-glove, leather-glove, nitrile-glove, and vinyl-glove conditions were evaluated to determine their effects on grip strength and three-point pinch. Forty-one adult volunteers from a local university and local hospital participated in the two-day study. The order of testing was randomly assigned. A hydraulic hand dynamometer and a hydraulic pinch gauge were used to evaluate grip strength and three-point pinch with no glove and with each glove type. Grip strength and three-point pinch were tested on separate days. Grip strength test results showed statistically significant differences (p < 0.05) for no glove vs. leather glove, no glove vs. nitrile glove, no glove vs. vinyl glove, leather glove vs. nitrile glove, and leather glove vs. vinyl glove, but no statistically significant difference for nitrile glove vs. vinyl glove. Three-point pinch test results also showed statistically significant differences (p < 0.05) for no glove vs. leather glove, leather glove vs. nitrile glove, and leather glove vs. vinyl glove, but no statistically significant differences for no glove vs. nitrile glove, no glove vs. vinyl glove, and nitrile glove vs. vinyl glove. The results indicate that glove type may have clinical applications for occupational and physical therapists whose patients use gloves in the workplace.
Subject(s)
Gloves, Protective , Gloves, Surgical , Hand Strength , Adolescent , Adult , Analysis of Variance , Female , Humans , Male , Middle Aged , Reference ValuesABSTRACT
General immunostimulants (adjuvants) are essential for generating immunity to many antigens. In bacterial infections, adjuvants are provided by components of the microorganism, e.g., lipopolysaccharide. However, it is unclear what provides the adjuvant effect for immune responses that are generated to tumors and many viruses. Here we show that cell injury and death of tumor or even normal cells provide a potent adjuvant effect for the stimulation of cytotoxic T lymphocyte responses. This adjuvant activity is constitutively present in the cytoplasm of cells and is increased in the cytoplasm of cells dying by apoptosis. The release of these components stimulates immune responses both locally and at a distance, and provides a simple mechanism to alert the immune system to potential danger in almost all pathological situations.
Subject(s)
Adjuvants, Immunologic , T-Lymphocytes, Cytotoxic/immunology , 3T3 Cells , Animals , Cell Line , Cytosol/immunology , Drosophila , HIV Envelope Protein gp120/immunology , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Ovalbumin/immunologyABSTRACT
Bone marrow (BM)-derived professional antigen-presenting cells (pAPCs) are required for the generation of cytotoxic T lymphocyte (CTL) responses to vaccinia virus and poliovirus. Furthermore, these BM-derived pAPCs require a functional transporter associated with antigen presentation (TAP). In this report we analyze the requirements for BM-derived pAPCs and TAP in the initiation of CTL responses to lymphocytic choriomeningitis virus (LCMV) and influenza virus (Flu). Our results indicate a requirement for BM-derived pAPCs for the CTL responses to these viruses. However, we found that the generation of CTLs to one LCMV epitope (LCMV nucleoprotein 396-404) was dependent on BM-derived pAPCs but, surprisingly, TAP independent. The study of the CTL response to Flu confirmed the existence of this BM-derived pAPC-dependent/TAP-independent CTL response and indicated that the TAP-independent pathway is approximately 10-300-fold less efficient than the TAP-dependent pathway.
Subject(s)
Antigen-Presenting Cells/immunology , Bone Marrow Cells/immunology , Bone Transplantation/immunology , Lymphocytic choriomeningitis virus/immunology , Poliovirus/immunology , T-Lymphocytes, Cytotoxic/immunology , Transplantation Chimera , Vaccinia virus/immunology , Animals , Antigen-Presenting Cells/cytology , Bone Marrow Cells/cytology , Crosses, Genetic , Cytotoxicity, Immunologic , Mice , Mice, Inbred C57BL , Mice, Inbred DBA , T-Lymphocytes, Cytotoxic/virology , Tumor Cells, CulturedABSTRACT
We evaluated the capacity of the secretory pathway or of different endocytic compartments in B cell lines to generate MHC class II-presented peptides from the antigen ovalbumin (OVA). Sorting signals from the transferrin receptor (TFR), targeted a chimeric OVA fusion protein to early endosomes and led to the generation of 8 of 12 presented peptides. Sorting signals from the lysosome-associated membrane protein 1 (LAMP-1), targeted an OVA fusion protein to lysosomes, and led to the generation of 9 of 12 peptides. In contrast, OVA with only a signal sequence led to the generation of only 2 presented peptides. There were both qualitative and quantitative differences in the generation of peptides from the different fusion proteins, suggesting that multiple distinct compartments are involved in generating different epitopes. One peptide was presented better from the TFR fusion protein, while all others were presented better from the LAMP-1 construct. Twelve peptides were generated from exogenously supplied OVA, including 3 peptides that were not generated from any of the fusion proteins. Since most endogenously synthesized foreign antigens are rarely presented on class II molecules, these studies further suggest a strategy whereby antigens in DNA-based vaccines could be targeted to endocytic compartments to enhance immunogenicity.