Immunotherapy has emerged as a current and future paradigm of cancer treatment, which utilizes the body’s immune system to eradicate cancer. Natural Killer (NK) cells as part of the innate immune system have immense potential in their anti-tumor cytotoxic activities and host cell surveillance properties. NK cells comprise approximately five to fifteen percent of peripheral blood lymphocytes and can be proliferated in vitro using recently developed methods with co-cultures with feeder cells (derived from engineered tumor cells) or plasma membrane (PM) particles, produced from the fore mentioned feeder cells, in combination with soluble cytokines. For efficient growth and maintenance of these NK cells, Interleukin-2 (IL-2) is utilized. IL-2 in solution, through receptor mediated signaling, stimulates proliferation of T-cells and NK cells. NK cells have lower responsiveness to IL-2 and consequently require a larger systemic dose to stimulate them as opposed to competing cell populations that have higher expression of receptors for IL-2, such as T-cells, which can have the effect of lower effective stimulation of NK cell growth. Such difference in the stimulatory capability of IL-2 toward NK cells and the short circulation lifetime of soluble IL-2 require higher dosages of soluble IL-2 for effective in vivo NK cell proliferation for therapeutic application against cancer, but is toxic. Therefore establishing another form of IL-2 delivery that improves its specific targeting to NK cells would be beneficial and may be crucial for novel therapeutic improvement. The Copik Laboratory has made an IL-2 fusion protein construct having a membrane anchor for expression of membrane-bound IL-2 on K562-41bbl-21 cells (K562-IL21). K562-IL21 cells are selectively recognized by NK cells and stimulate their proliferation and cytotoxicity. Hence, a K562-IL21 membrane–bound IL-2 form should be targeted to NK cells with IL-2 delivery. K562-IL21-2 cells were then used to prepare PM21-2 particles which have the potential to provide NK cell targeted, long-lived form of IL-2 for use as an injectable drug for in vivo adjuvant stimulation of NK cells. The presence of IL-2 on the in the PM21-2 particle product was verified by Western blot, and ELISA. Particle preparations from the modified K562 cells should possess characteristics that allow them to possibly replace soluble IL-2 and more specifically increase the numbers or anti-tumor activity of NK cell populations. The effect of PM21-2 particles was studied in in vitro culture based experiments, which tested the effectiveness the PM21-2 particles to induce selective NK cells expansion as compared to PM21 particles in the presence or absence of soluble IL-2.

Circulating angiogenic cells (CACs) are early predictors of cardiovascular health and are inversely proportional to related outcomes. Increased number and function of CACs is seen in healthy individuals compared with individuals with cardiovascular disease (CVD). Exercise increases CAC number and function in CVD populations, through a nitric oxide-mediated mechanism. Inactivity is a growing concern in industrialized nations; it is an independent risk factor for CVD and is linked to increased mortality. The purpose of this study was to understand the effect of reduced physical activity (rPA) on two CAC populations (CFU-Hill and CD34+) in highly active individuals. We examined the mechanisms underlying changes in CAC function as a result of rPA with maintained energy balance. The two sub-populations of CACs responded differently to rPA. CFU-Hill CACs, decreased in number and amount of intracellular nitric oxide while CD34+ cells, did not change. Gene expression analyses indicated that oxidative stress- related genes did not change in CFU-Hill cells with rPA. However, correlations between CFU-Hill cell numbers, intracellular nitric oxide, and genes that are related to nitric oxide were observed. We concluded that rPA caused the observed decrease in CFU-Hill number and intracellular nitric oxide through a decrease in nitric oxide cellular availability, not oxidative stress.

Huntington’s disease is an incurable, progressive neurological disorder characterized by loss of motor control, psychiatric dysfunction, and eventual dystonia leading to death. Despite the fact that this disorder is caused by a mutation in one single gene, there is no cure. The mutant Huntingtin (mHtt) protein is expressed ubiquitously throughout the brain but frank cell death is limited to the striatum. Recent work has suggested that Rhes, Ras homolog enriched in striatum, which is selectively expressed in the striatum, may play a role in Huntington’s disease neuropathology. In vitro studies have shown Rhes to be an E3 ligase for the post-translational modification protein SUMO. Rhes increases binding of SUMO to mHtt which competes for the same binding site as Ubiquitin. SUMOylation of mHtt leads to disaggregation and cellular death, whereas ubiquitination leads to aggregation and cellular protection. In a previous study we showed that deletion of Rhes caused a decrease in the Huntington’s disease phenotype in mice. We hypothesized that mice lacking Rhes would also show increased aggregation in the striatum and this increased aggregation would correlate in a rescue of behavioral symptoms. Despite the prior in vitro and in vivo evidence, deletion of Rhes in vivo did not alter the aggregation of mHtt in the striatum of mice however deletion of Rhes still showed a rescue from the diseased phenotype. This result would indicate that deletion of Rhes alters the neurobehavioral phenotype of Huntington’s disease through a different pathway than promoting aggregation in striatal cells.

A proteína miostatina, é um regulador negativo do crescimento muscular e a modulação de sua expressão pode consistir em tratamento para distrofias musculares. Nós estudamos expressão endógena da miostatina no músculos gastrocnêmio e diafragma de 4 modelos murinos de degeneração muscular: os camundongos Dmdmdx, SJL/J, Largemyd e Lama2dy-2J/J. Observamos que a miostatina é menos expressa no músculo gastrocnêmio do que diafragma normal, refletindo um músculo mais sujeito a lesão. Nas quatro linhagens distróficas a miostatina é menos expressa do que em camundongos normais, tanto no músculo gastrocnêmio como diafragma, sem diferença entre os dois. A analise comparativa da degeneração e regeneração muscular mostrou maior correlação da inibição da miostatina com o padrão de degeneração. Nossos resultados sugerem que o processo de degeneração, quando iniciado, e independentemente de seu grau, causa molecular primária, ou músculo afetado, parece atuar de forma similar na inibição da expressão da miostatina, possivelmente como estimulo a regeneração do dano. / Myostatin is a negative regulator of muscle growth, and its inhibition has been considered a therapeutic strategy for muscular dystrophies. We evaluated the endogenous expression of myostatin in the gastrocnemius and diaphragm muscles from 4 mouse dystrophic models including Dmdmdx, SJL/J>, Largemyd and Lama2dy2J/J. In normal mice, we observed that myostatin is less expressed in the gastrocnemius than in the diaphragm, reflecting a muscle most prone to lesions. In the 4 dystrophic models, myostatin expression was reduced, in both gastrocnemius and diaphragm muscles. The comparative analysis of the histopathology of the muscles with the expression of myostatin showed a stronger correlation with the pattern of degeneration then regeneration. Our results suggest that, when started, the process of degeneration of the muscle, independently of the primary molecular defect, or degree, seems to act in a similar pathway leading to the inhibition of the expression of myostatin in the affected muscles, possibly as a stimulus to regeneration of damage.

Sublinhagens de camundongos AIRmax e AIRmin homozigotas para os alelos R ou S do gene Slc11a1 apresentam distinta capacidade regenerativa à perfuração de suas orelhas. Animais AIRmaxSS exibiram regeneração tecidual precoce em comparação aos animais AIRmaxRR, sugerindo que o alelo S favorece a regeneração nestes animais. Camundongos das sublinhagens AIRmin não apresentaram regeneração após perfuração de suas orelhas. Em resposta ao estímulo, animais AIRmaxSS exibiram inflamação local mais intensa e tardia do que animais AIRmaxRR, demonstrando elevados níveis de MPO e edema, e influxo celular predominantemente de neutrófilos. Ensaios de expressão gênica global demonstraram genes diferencialmente expressos entre as sublinhagens, evidenciando genes sobre-representados no tema biológico proliferação celular em ambas sublinhagens, enquanto somente nos animais AIRmaxSS ocorreu sobre-representação para resposta inflamatória nos genes ativados e para contração muscular nos genes reprimidos. Os resultados de microarray foram validados por qPCR. / Homozygous AIRmax and AIRmin sublines for Slc11a1 R and S alleles present distinct regenerative capacity to the ear hole. AIRmaxSS mice exhibited early tissue regeneration compared to AIRmaxRR animals, suggesting that the Slc11a1 S allele promotes regeneration in these animals. AIRmin sublines didnt show regeneration after ear punch. In response to the stimulus, AIRmaxSS animals exhibited more intense and later local inflammation than AIRmaxRR animals, presenting elevated levels of MPO, edema and cellular influx predominantly of neutrophils. Global gene expression analysis showed differentially-expressed genes between the sublines, in which over-represented biological theme is cell proliferation in both sublines. AIRmaxSS animals displayed over-representation of inflammatory response in up-regulated genes and of muscle contraction in down-regulated genes. Microarray results were validated by using quantitative PCR.

Chlamydia trachomatis is the most prevalent agent of bacterial sexually transmitted infections in the world. However, a profuse number of cases are unreported, as the infection is often asymptomatic. Sequelae such as pelvic inflammatory disease, an increased risk of cervical cancer, premature birth, and perinatal infections in pregnant women can occur. Inflammation occurs in the body in response to infection or injury. Although inflammation can lead to some unwanted secondary effects, such as pain, it serves to return the body to homeostasis by restoring injured tissues and eliminating pathogens. One recently identified connection between the central nervous system and the immune system that regulates inflammation is the cholinergic anti-inflammatory pathway (CAP). In the CAP, pathogen-associated molecular patterns stimulate the vagus nerve to activate the pathway, which ultimately results in acetylcholine (ACh) release, which down regulates inflammation. We hypothesized that genital chlamydial infection would increase the expression of choline acetyltransferase (ChAT), the enzyme that synthesizes ACh, in the female murine genital tract, therefore down regulating inflammation and promoting chlamydial infection. Transgenic female mice carrying a ChAT-promoter driven GFP reporter gene were vaginally infected with C. muridarum. Mice were sacrificed on days 3, 9, 15, and 21 post infection; cervical, uterine horn, and ovarian tissues were removed and embedded in paraffin. Small sections of each tissue were cut and mounted onto slides. The tissue sections were then stained for the expression of ChAT using immunohistochemical techniques. Finally, tissue sections were viewed under a microscope for positive staining and the data was analyzed. The results indicated that there is a significant increase in the number of cells that express ChAT in genital tract of chlamydia-infected mice versus non-infected mice.

Clinical radiotherapy is used to treat a variety of brain tumors within the central nervous system. While effective, it can result in progressive and debilitating cognitive impairment that can diminish quality of life. These impairments have been linked to hippocampal dysfunction and corresponding deficits in spatial learning and memory. Mossy cells are a major population of excitatory neurons located within the dentate hilus and highly involved in hippocampal circuitry. They play critical roles in spatial navigation, neurogenesis, memory, and are particularly vulnerable to a variety of neurotoxic insults. However, their sensitivity to ionizing radiation has yet to be investigated in detail. I hypothesize that mossy cells are critical targets for ionizing radiation, whereby damage to these targets contributes to the mechanisms associated with radiation-induced hippocampal dysfunction. To test this idea, wild-type mice were exposed to clinically relevant doses of cranial x-ray irradiation and their hippocampi were examined 1 month and 3 months post treatment. A significant decline in both the number of mossy cells and their activity were observed. In addition, dentate granular cells demonstrated reduced levels of activity, as well as reduced proliferation within the subgranular zone. A second cohort of mice was introduced to a novel environment in order to induce the expression of immediate early genes. Analysis of c-Fos mRNA yielded a significant increase in control but not irradiated animals, suggesting that radiotherapy impaired immediate early gene expression and resultant functional behavioral outcomes. These findings support the proposition that radiation-induced damage to mossy cells contributes to hippocampal deficiencies which result in cognitive dysfunction.

A stochastic-delay differential equation (SDDE) model of a small neural network with recurrent inhibition is presented and analyzed. The model exhibits unexpected transient behavior: oscillations that occur at the boundary of the basins of attraction when the system is bistable. These are known as delay-induced transitory oscillations (DITOs). This behavior is analyzed in the context of stochastic resonance, an unintuitive, though widely researched phenomenon in physical bistable systems where noise can play in constructive role in strengthening an input signal. A method for modeling the dynamics using a probabilistic three-state model is proposed, and supported with numerical evidence. The potential implications of this dynamical phenomenon to nocturnal frontal lobe epilepsy (NFLE) are also discussed.

The effects of mechanical forces on endothelial cell function and behavior are well documented, but have not been fully characterized. Specifically, fluid pressure has been shown to elicit physical and chemical responses known to be involved in the initiation and progression of endothelial cell-mediated vascularization. Central to the process of vascularization is the formation of tube-like structures. This process—tubulogenesis—is essential to both the physiological and pathological growth of tissues. Given the known effects of pressure on endothelial cells and its ubiquitous presence in the vasculature, we investigated pressure as a magnitude-dependent parameter for the regulation of endothelial tubulogenic activity. To accomplish this, we exposed two- and three-dimensional bovine aortic endothelial cell (BAEC) cultures to static pressures of 0, 20, and 40 mmHg for 3 and 4 days. The most significant findings were: (1) cells in two-dimensional culture exposed to 20, but not 40, mmHg exhibited significantly (p < 0.05) increased expression of both VEGF-C and VEGFR-3, and (2) cells in three-dimensional culture exposed to 20, but not 40, mmHg exhibited significant (p > 0.05) increases in endothelial sprouting. These findings evidence the utility of pressure as a selective modulator of tissue microvascularization in vitro and implicates pressure as factor in pathological tubulogenesis in vivo.

Sublinhagens de camundongos AIRmax e AIRmin homozigotas para os alelos R ou S do gene Slc11a1 apresentam distinta capacidade regenerativa à perfuração de suas orelhas. Animais AIRmaxSS exibiram regeneração tecidual precoce em comparação aos animais AIRmaxRR, sugerindo que o alelo S favorece a regeneração nestes animais. Camundongos das sublinhagens AIRmin não apresentaram regeneração após perfuração de suas orelhas. Em resposta ao estímulo, animais AIRmaxSS exibiram inflamação local mais intensa e tardia do que animais AIRmaxRR, demonstrando elevados níveis de MPO e edema, e influxo celular predominantemente de neutrófilos. Ensaios de expressão gênica global demonstraram genes diferencialmente expressos entre as sublinhagens, evidenciando genes sobre-representados no tema biológico proliferação celular em ambas sublinhagens, enquanto somente nos animais AIRmaxSS ocorreu sobre-representação para resposta inflamatória nos genes ativados e para contração muscular nos genes reprimidos. Os resultados de microarray foram validados por qPCR. / Homozygous AIRmax and AIRmin sublines for Slc11a1 R and S alleles present distinct regenerative capacity to the ear hole. AIRmaxSS mice exhibited early tissue regeneration compared to AIRmaxRR animals, suggesting that the Slc11a1 S allele promotes regeneration in these animals. AIRmin sublines didnt show regeneration after ear punch. In response to the stimulus, AIRmaxSS animals exhibited more intense and later local inflammation than AIRmaxRR animals, presenting elevated levels of MPO, edema and cellular influx predominantly of neutrophils. Global gene expression analysis showed differentially-expressed genes between the sublines, in which over-represented biological theme is cell proliferation in both sublines. AIRmaxSS animals displayed over-representation of inflammatory response in up-regulated genes and of muscle contraction in down-regulated genes. Microarray results were validated by using quantitative PCR.