Effects of rIL2/anti-IL2 antibody complex on chikungunya virus-induced chronic arthritis in a mouse model.

Chikungunya virus (CHIKV) is characterized by disabling joint pain that can cause persistent arthritis in approximately one-fourth of patients. Currently, no standard treatments are available for chronic CHIKV arthritis. Our preliminary data suggest that decreases in interleukin-2 (IL2) levels and regulatory T cell (Treg) function may play a role in CHIKV arthritis pathogenesis. Low-dose IL2-based therapies for autoimmune diseases have been shown to up-regulate Tregs, and complexing IL2 with anti-IL2 antibodies can prolong the half-life of IL2. A mouse model for post-CHIKV arthritis was used to test the effects of recombinant IL2 (rIL2), an anti-IL2 monoclonal antibody (mAb), and the complex on tarsal joint inflammation, peripheral IL2 levels, Tregs, CD4 + effector T cells (Teff), and histological disease scoring. The complex treatment resulted in the highest levels of IL2 and Tregs, but also increased Teffs, and therefore did not significantly reduce inflammation or disease scores. However, the antibody group, which had moderately increased levels of IL2 and activated Tregs, resulted in a decreased average disease score. These results suggest the rIL2/anti-IL2 complex stimulates both Tregs and Teffs in post-CHIKV arthritis, while the anti-IL2 mAb increases IL2 availability enough to shift the immune environment towards a tolerogenic one.

Effects of IL2/anti-IL2 antibody complex on chikungunya virus-induced arthritis in a mouse model.

Chikungunya virus (CHIKV) is characterized by disabling joint pain that can cause persistent arthritis in approximately one-fourth of patients. Currently, no standard treatments are available for chronic CHIKV arthritis. Our preliminary data suggest that decreases in interleukin-2 (IL2) levels and regulatory T cell (Treg) function may play a role in CHIKV arthritis pathogenesis. Low-dose IL2-based therapies for autoimmune diseases have been shown to up-regulate Tregs, and complexing IL2 with anti-IL2 antibodies can prolong the half-life of IL2. A mouse model for post-CHIKV arthritis was used to test the effects of IL-2, an anti-IL2 monoclonal antibody (mAb), and the complex on tarsal joint inflammation, peripheral IL2 levels, Tregs, effector (Teff) T cells, and histological disease scoring. The complex treatment resulted in the highest levels of IL2 and Tregs, but also increased Teffs, and therefore did not significantly reduce inflammation or disease scores. However, the antibody group, which had moderately increased levels of IL2 and activated Tregs, resulted in a decreased average disease score. These results suggest the IL2/anti-IL2 complex stimulates both Tregs and Teffs in post-CHIKV arthritis, while the anti-IL2 mAb increases IL2 availability enough to shift the immune environment towards a tolerogenic one.

A Mouse Model for Studying Post-Acute Arthritis of Chikungunya.

Chikungunya virus (CHIKV) was introduced to the Americas in 2013, causing two million infections across over thirty countries. CHIKV causes a chronic debilitating arthritis in one fourth of infected individuals and currently evidence-based targeted therapies for the treatment of CHIKV arthritis are lacking. Multiple mouse models of chikungunya have been developed to study acute CHIKV infection. In humans, post-CHIKV arthritis may persist for months to years after viremia from a CHIKV infection has resolved. Therefore, the development of a mouse model of post-acute arthritis of chikungunya may facilitate the study of potential novel therapeutics for this arthritis. In this article we describe the development of a wild-type immunocompetent C57BL/6 mouse model for post-acute arthritis of chikungunya, including a histologic inflammation scoring system, as well as suggestions for how this mouse model may be used to examine the efficacy of novel therapies for CHIKV arthritis.

Phenotypic Characterization and Brain Structure Analysis of Calcium Channel Subunit α2δ-2 Mutant (Ducky) and α2δ Double Knockout Mice.

Auxiliary α2δ subunits of voltage-gated calcium channels modulate channel trafficking, current properties, and synapse formation. Three of the four isoforms (α2δ-1, α2δ-2, and α2δ-3) are abundantly expressed in the brain; however, of the available knockout models, only α2δ-2 knockout or mutant mice display an obvious abnormal neurological phenotype. Thus, we hypothesize that the neuronal α2δ isoforms may have partially specific as well as redundant functions. To address this, we generated three distinct α2δ double knockout mouse models by crossbreeding single knockout (α2δ-1 and -3) or mutant (α2δ-2/ducky) mice. Here, we provide a first phenotypic description and brain structure analysis. We found that genotypic distribution of neonatal litters in distinct α2δ-1/-2, α2δ-1/-3, and α2δ-2/-3 breeding combinations did not conform to Mendel's law, suggesting premature lethality of single and double knockout mice. Notably, high occurrences of infant mortality correlated with the absence of specific α2δ isoforms (α2Δ-2 > α2δ-1 > α2δ-3), and was particularly observed in cages with behaviorally abnormal parenting animals of α2δ-2/-3 cross-breedings. Juvenile α2δ-1/-2 and α2δ-2/-3 double knockout mice displayed a waddling gate similar to ducky mice. However, in contrast to ducky and α2δ-1/-3 double knockout animals, α2δ-1/-2 and α2δ-2/-3 double knockout mice showed a more severe disease progression and highly impaired development. The observed phenotypes within the individual mouse lines may be linked to differences in the volume of specific brain regions. Reduced cortical volume in ducky mice, for example, was associated with a progressively decreased space between neurons, suggesting a reduction of total synaptic connections. Taken together, our findings show that α2δ subunits differentially regulate premature survival, postnatal growth, brain development, and behavior, suggesting specific neuronal functions in health and disease.

The Association Between Race, Obesity, and Sperm Quality Among Men Attending a University Physician Practice in Washington, DC.

A decades-long decline in sperm counts in Western countries has coincided with an increase in obesity rates, prompting study into their association. Few of these studies have incorporated men of color, the sperm health of whom is relatively unknown. The present exploratory study evaluated the association between body mass index (BMI), race, ethnicity, and sperm parameters among a diverse sample of U.S. men attending a Washington, DC physician practice. Semen samples were collected and processed at a single laboratory and sperm concentration, motility, morphology, and count were evaluated according to World Health Organization (WHO) 5th edition criteria. Multivariate models accounted for covariates related to sperm health. The study population (n = 128) was largely obese (45.3%) or overweight (34.4%), and 36.0% were black or Hispanic. Black men had lower adjusted sperm concentration compared to white men (75.0 million/mL to 107.4 million/mL, p = .01) and were more likely to have oligozoospermia (p = .01), asthenozoospermia (p = .004), and low sperm count (p < .0001). Hispanic men had higher adjusted sperm concentration compared to non-Hispanic men (124.5 million/mL to 62.1 million/mL, p = .007) and were less likely to have teratozoospermia (p = .001). Obesity and BMI were associated with lower sperm motility and count in crude models only. Given the study's sample size its findings should be interpreted with caution but align with the limited epidemiological literature to date that has evaluated racial and ethnic differences in semen quality. Heightened clinical research attention is needed to ensure men of color are included in representative numbers in studies of urologic and andrologic health.

Creating prognostic systems for cancer patients: A demonstration using breast cancer.

Integrating additional prognostic factors into the tumor, lymph node, metastasis staging system improves the relative stratification of cancer patients and enhances the accuracy in planning their treatment options and predicting clinical outcomes. We describe a novel approach to build prognostic systems for cancer patients that can admit any number of prognostic factors. In the approach, an unsupervised learning algorithm was used to create dendrograms and the C-index was used to cut dendrograms to generate prognostic groups. Breast cancer data from the Surveillance, Epidemiology, and End Results Program of the National Cancer Institute were used for demonstration. Two relative prognostic systems were created for breast cancer. One system (7 prognostic groups with C-index = 0.7295) was based on tumor size, regional lymph nodes, and no distant metastasis. The other system (7 prognostic groups with C-index = 0.7458) was based on tumor size, regional lymph nodes, no distant metastasis, grade, estrogen receptor, progesterone receptor, and age. The dendrograms showed a relationship between survival and prognostic factors. The proposed approach is able to create prognostic systems that have a good accuracy in survival prediction and provide a manageable number of prognostic groups. The prognostic systems have the potential to permit a thorough database analysis of all information relevant to decision-making in patient management and prognosis.

The anatomy of the TNM for colon cancer.

BACKGROUND: To visualize the anatomy as revealed by dendrograms of the tumor, lymph node, and metastasis (TNM) staging system for colon cancer and compare it with the Dukes' system. METHODS: A hierarchical clustering algorithm generated tree-structured dendrograms that stratified patients according to survival only. The dendrograms were constructed with the same prognostic variables used for the TNM. Because combinations of prognostic factors were stratified only on survival, additional factors of any number and type could be integrated into the TNM without changing the TNM categories. RESULTS: The algorithm provided a step-by-step visualization of the TNM and the Dukes' system for colon cancer. Dendrograms and associated 5-year survival rates were generated for the T category only, the N category only, the T, N combination, and combinations of the T, N, and M, and the T, N, M with histological grade. Dendrograms revealed visual differences between the structure of TNM and the Dukes' system of staging. Dendrograms also revealed how variations in prognostic factors changed survival. By cutting dendrograms along their dissimilarity axis, multiple prognostic subgroups could be created for colon cancer that may reflect outcomes that are more accurate to estimate. CONCLUSIONS: Dendrograms provide a new way to view cancer patient staging. They reveal a visual step-by-step hierarchical relationship between survival rates and combinations of prognostic variables. The dendrograms also revealed fundamental differences between the TNM and the Dukes system of staging. By stratifying on survival only, additional factors including molecular factors can be added to the TNM, because it classifies patients according to survival rates only and not according to pre-set rules of prognostic factors and stage groups. The clinical implications of stratifying only survival are discussed.

Gouty Tenosynovitis of the Distal Biceps Tendon Insertion Complicated by Partial Rupture: First Case and Review of the Literature.

Background: Given the appreciable prevalence of gout, gout-induced tendon ruptures in the upper extremity are extremely rare. Although these events have been reported only 5 times in the literature, all in patients with a risk factor for or history of gout, they have conspicuously never been diagnosed in the shoulder or elbow. Methods: A 45-year-old, right-hand-dominant man with a history of gout presented with pain in his right anterior elbow and weakness in his forearm after a trivial injury. Results: Here, we report the first case of gouty tenosynovitis of the distal biceps tendon insertion complicated by partial rupture, a composite diagnosis supported by both intraoperative and histological observations. Conclusions: In patients who are clinically diagnosed with biceps tendon rupture and have a history of gout, it is important to consider the possibility of a gout-related pathological manifestation causing or simulating tendon rupture.

Loss of α2δ-1 Calcium Channel Subunit Function Increases the Susceptibility for Diabetes.

Reduced pancreatic ß-cell function or mass is the critical problem in developing diabetes. Insulin release from ß-cells depends on Ca2+ influx through high voltage-gated Ca2+ channels (HVCCs). Ca2+ influx also regulates insulin synthesis and insulin granule priming and contributes to ß-cell electrical activity. The HVCCs are multisubunit protein complexes composed of a pore-forming α1 and auxiliary ß and α2δ subunits. α2δ is a key regulator of membrane incorporation and function of HVCCs. Here we show that genetic deletion of α2δ-1, the dominant α2δ subunit in pancreatic islets, results in glucose intolerance and diabetes without affecting insulin sensitivity. Lack of the α2δ-1 subunit reduces the Ca2+ currents through all HVCC isoforms expressed in ß-cells equally in male and female mice. The reduced Ca2+ influx alters the kinetics and amplitude of the global Ca2+ response to glucose in pancreatic islets and significantly reduces insulin release in both sexes. The progression of diabetes in males is aggravated by a selective loss of ß-cell mass, while a stronger basal insulin release alleviates the diabetes symptoms in most α2δ-1-/- female mice. Together, these findings demonstrate that the loss of the Ca2+ channel α2δ-1 subunit function increases the susceptibility for developing diabetes in a sex-dependent manner.

Tetrodotoxin-sensitive Ca2+ Currents, but No T-type Currents in Normal, Hypertrophied, and Failing Mouse Cardiomyocytes.

AIMS: To obtain functional evidence that ICa,T is involved in the pathogenesis of cardiac hypertrophy and heart failure. We unexpectedly identified ICa(TTX) rather than ICa,T, therefore, we adjusted our aim to encompass these findings. METHODS AND RESULTS: We investigated (1) Cav3.1 (α1G) transgenic (Tg) mice compared with nontransgenic (tTA-Ntg); (2) Cav3.1-deficient mice (Cav3.1) compared with wild type (Wt) after chemically and surgically induced cardiac remodeling; and (3) spontaneous hypertensive rats and thoracic aortic constriction (TAC) rats. Whole-cell patch-clamp technique was used to measure ICa in ventricular myocytes. Cav3.1-Tg expressed ICa,T (-18.35 ± 1.02 pA/pF at -40 mV) without signs of compromised cardiac function. While we failed to detect ICa,T after hypertrophic stimuli, instead we demonstrated that both Wt and Cav3.1 mouse exhibit ICa(TTX). Using TAC rats, only 2 of 24 VMs showed ICa,T under our experimental conditions. Without TTX, ICa(TTX) occurred in VMs from Wt, spontaneous hypertensive rats, and TAC rats also. CONCLUSIONS: These findings demonstrate for the first time that mouse VMs express ICa(TTX). We suggest that future studies should take into consideration the measuring conditions when interpreting ICa,T reappearance in ventricular myocytes in response to hypertrophic stress. Contamination with ICa(TTX) could possibly confuse the relevance of the data.

Beta protein 1 homeoprotein induces cell growth and estrogen-independent tumorigenesis by binding to the estrogen receptor in breast cancer.

Expression of Beta Protein 1 (BP1), a homeotic transcription factor, increases during breast cancer progression and may be associated with tumor aggressiveness. In our present work, we investigate the influence of BP1 on breast tumor formation and size in vitro and in vivo. Cells overexpressing BP1 showed higher viability when grown in the absence of serum (p < 0.05), greater invasive potential (p < 0.05) and formed larger colonies (p < 0.004) compared with the controls. To determine the influence of BP1 overexpression on tumor characteristics, MCF-7 cells transfected with either empty vector (V1) or overexpressor plasmids (O2 and O4) were injected into the fat pads of athymic nude mice. Tumors grew larger in mice receiving O2 or O4 cells than in mice receiving V1 cells. Moreover, BP1 mRNA expression levels were positively correlated with tumor size in patients (p = 0.01). Interestingly, 20% of mice injected with O2 or O4 cells developed tumors in the absence of estrogen, while no mice receiving V1 cells developed tumors. Several mechanisms of estrogen independent tumor formation related to BP1 were established. These data are consistent with the fact that expression of breast cancer anti-estrogen resistance 1 (BCAR1) was increased in O2 compared to V1 cells (p < 0.01). Importantly, O2 cells exhibited increased proliferation when treated with tamoxifen, while V1 cells showed growth inhibition. Overall, BP1 overexpresssion in MCF-7 breast cancer cells leads to increased cell growth, estrogen-independent tumor formation, and increased proliferation. These findings suggest that BP1 may be an important biomarker and therapeutic target in ER positive breast cancer.

Effect of knockout of α2δ-1 on action potentials in mouse sensory neurons.

Gene deletion of the voltage-gated calcium channel auxiliary subunit α2δ-1 has been shown previously to have a cardiovascular phenotype, and a reduction in mechano- and cold sensitivity, coupled with delayed development of neuropathic allodynia. We have also previously shown that dorsal root ganglion (DRG) neuron calcium channel currents were significantly reduced in α2δ-1 knockout mice. To extend our findings in these sensory neurons, we have examined here the properties of action potentials (APs) in DRG neurons from α2δ-1 knockout mice in comparison to their wild-type (WT) littermates, in order to dissect how the calcium channels that are affected by α2δ-1 knockout are involved in setting the duration of individual APs and their firing frequency. Our main findings are that there is reduced Ca(2+) entry on single AP stimulation, particularly in the axon proximal segment, reduced AP duration and reduced firing frequency to a 400 ms stimulation in α2δ-1 knockout neurons, consistent with the expected role of voltage-gated calcium channels in these events. Furthermore, lower intracellular Ca(2+) buffering also resulted in reduced AP duration, and a lower frequency of AP firing in WT neurons, mimicking the effect of α2δ-1 knockout. By contrast, we did not obtain any consistent evidence for the involvement of Ca(2+)-activation of large conductance calcium-activated potassium (BK) and small conductance calcium-activated potassium (SK) channels in these events. In conclusion, the reduced Ca(2+) elevation as a result of single AP stimulation is likely to result from the reduced duration of the AP in α2δ-1 knockout sensory neurons.This article is part of the themed issue 'Evolution brings Ca(2+) and ATP together to control life and death'.

An Algorithm for Creating Prognostic Systems for Cancer.

The TNM staging system is universally used for classification of cancer. This system is limited since it uses only three factors (tumor size, extent of spread to lymph nodes, and status of distant metastasis) to generate stage groups. To provide a more accurate description of cancer and thus better patient care, additional factors or variables should be used to classify cancer. In this paper we propose a hierarchical clustering algorithm to develop prognostic systems that classify cancer according to multiple prognostic factors. This algorithm has many potential applications in augmenting the data currently obtained in a staging system by allowing more prognostic factors to be incorporated. The algorithm clusters combinations of prognostic factors that are formed using categories of factors. The dissimilarity between two combinations is determined by the area between two corresponding survival curves. Groups from cutting the dendrogram and survival curves of the individual groups define our prognostic systems that classify patients using survival outcomes. A demonstration of the proposed algorithm is given for patients with breast cancer from the Surveillance, Epidemiology, and End Results (SEER) Program of the National Cancer Institute.

An algorithm for expanding the TNM staging system.

AIM: We describe a new method to expand the tumor, lymph node, metastasis (TNM) staging system using a clustering algorithm. Cases of breast cancer were used for demonstration. MATERIALS & METHODS: An unsupervised ensemble-learning algorithm was used to create dendrograms. Cutting the dendrograms produced prognostic systems. RESULTS: Prognostic systems contained groups of patients with similar outcomes. The prognostic systems based on tumor size and lymph node status recapitulated the general structure of the TNM for breast cancer. The prognostic systems based on tumor size, lymph node status, histologic grade and estrogen receptor status revealed a more detailed stratification of patients when grade and estrogen receptor status were added. CONCLUSION: Prognostic systems from cutting the dendrogram have the potential to improve and expand the TNM.

The role of PET scan in monitoring the progression of fibrosing mediastinitis.

We present the case of a 31-year-old man who presented with acute chest pain. Computed tomography scan showed a mediastinal mass engulfing right main-stem bronchus and another mass surrounding descending aorta. Positron emission tomography (PET) scan showed high mass metabolic activity. Histopathological evaluation revealed fibroinflammatory scarring. He was diagnosed with idiopathic fibrosing mediastinitis, started on prednisone and tamoxifen treatment, and monitored with serial PET scans. Nine months after treatment initiation, paraaortic abnormality had resolved and mediastinal mass had regressed.

Medullary thyroid carcinoma presenting as a supraglottic mass.

We report a rare case of medullary thyroid carcinoma that presented as a metastasis to the supraglottic larynx. A 92-year-old man with a 3-month history of voice change and airway obstruction was diagnosed with medullary thyroid carcinoma metastatic to the supraglottis. Excision of the mass, total thyroidectomy, and elective neck dissection were recommended, but the patient declined because of his advanced age. Medullary carcinoma of the thyroid gland is a rare neuroendocrine tumor with a poor prognosis when associated with a distant metastasis. To the best of our knowledge, this is the first case of a medullary carcinoma of the thyroid presenting as a supraglottic mass. Total thyroidectomy, neck dissection, and surgical excision of the entire tumor comprise the treatment of choice.

Histologic grade remains a prognostic factor for breast cancer regardless of the number of positive lymph nodes and tumor size: a study of 161 708 cases of breast cancer from the SEER Program.

CONTEXT: The appropriate staging of breast cancers includes an evaluation of tumor size and nodal status. Histologic grade in breast cancer, though important and assessed for all tumors, is not integrated within tumor staging. OBJECTIVE: To determine whether the histologic grade remains a prognostic factor for breast cancer regardless of tumor size and the number of involved axillary lymph nodes. DESIGN: By using a new clustering algorithm, the 10-year survival for every combination of T, N, and the histologic grade was determined for cases of breast cancer obtained from the Surveillance, Epidemiology, and End Results Program of the National Cancer Institute. There were 36 combinations of TN, defined according to the American Joint Committee on Cancer, and grade. RESULTS: For each combination of T and N, a categorical increase in the histologic grade was associated with a progressive decrease in 10-year survival regardless of the number of involved axillary lymph nodes or size of the primary tumor. Absolute survival differences between high and low grade persisted despite larger tumor sizes and greater nodal involvement, though trends were apparent with increasing breast cancer stage. Statistical significance depended on the number of cases for each combination. CONCLUSIONS: Histologic grade continues to be of prognostic importance for overall survival despite tumor size and nodal status. Furthermore, these results seem to indicate that the assignment of the histologic grade has been consistent among pathologists when evaluated in a large data set of patients with breast cancer. The incorporation of histologic grade in TNM staging for breast cancer provides important prognostic information.