Monobody adapter for functional antibody display on nanoparticles for adaptable targeted delivery applications

Vascular endothelial cells (ECs) play a central role in the pathophysiology of many diseases. The use of targeted nanoparticles (NPs) to deliver therapeutics to ECs could dramatically improve efficacy by providing elevated and sustained intracellular drug levels. However, achieving sufficient levels of NP targeting in human settings remains elusive. Here, we overcome this barrier by engineering a monobody adapter that presents antibodies on the NP surface in a manner that fully preserves their antigen-binding function. This system improves targeting efficacy in cultured ECs under flow by >1000-fold over conventional antibody immobilization using amine coupling and enables robust delivery of NPs to the ECs of human kidneys undergoing ex vivo perfusion, a clinical setting used for organ transplant. Our monobody adapter also enables a simple plug-and-play capacity that facilitates the evaluation of a diverse array of targeted NPs. This technology has the potential to simplify and possibly accelerate both the development and clinical translation of EC-targeted nanomedicines.

Investigating changes in anger and aggression in offenders with high levels of psychopathic traits attending the Chromis violence reduction programme

BACKGROUND

Chromis was accredited by the Correction Services Accreditation Panel in 2005 as an intervention designed to reduce violence in offenders whose level or combination of psychopathic traits disrupts their ability to engage in treatment and change. It runs as part of the regime in the dangerous and severe personality disorder unit in HM Prison Frankland (Westgate). A multiple case study investigation into changes over time in participants is currently underway, part of which is reported here.

AIMS

This paper reports on information relating to changes in anger and aggression in Chromis completers.

METHODS

Change in psychometrics and observed incidents of verbal and physical aggression are considered for five case study participants who have completed Chromis and progressed from Westgate to a different location.

RESULTS

Findings suggest that cases experienced a reduction in self-reported anger, and expected incidents of physical aggression but had higher than expected levels of verbal aggression after leaving Westgate.

CONCLUSIONS

These findings offer cautious optimism for the effectiveness of Chromis, although methodological limitations must also be considered. Findings may be seen as positive indicators of Chromis, or at least the approach to working with these offenders across Westgate, in reducing violence.

IMPLICATIONS FOR PRACTICE

Findings support the continued delivery and evaluation of Chromis. There may be benefit in exploring ways to further understand and address verbal aggression in participants.

Immunohistochemistry in the evaluation of neovascularization in tumor xenografts

Angiogenesis, or neovascularization, is known to play an important role in the neoplastic progression leading to metastasis. CD31 or Factor VIII-related antigen (F VIII RAg) immunohistochemistry is widely used in experimental studies for quantifying tumor neovascularization in immunocompromised animal models implanted with transformed human cell lines. Quantification, however, can be affected by variations in the methodology used to measure vascularization including antibody selection, antigen retrieval (AR) pretreatment, and evaluation techniques. To examine this further, we investigated the microvessel density (MVD) and the intensity of microvascular staining among five different human tumor xenografts and a mouse syngeneic tumor using anti-CD31 and F VIII RAg immunohistochemical staining. Different AR methods also were evaluated. Maximal retrieval of CD31 was achieved using 0.5 M Tris (pH 10) buffer, while maximum retrieval of F VIII RAg was achieved using 0.05% pepsin treatment of tissue sections. For each optimized retrieval condition, anti-CD31 highlighted small vessels better than F VIII RAg. Furthermore, the MVD of CD31 was significantly greater than that of F VIII RAg decorated vessels (p<0.001). The choice of antibody and AR method has a significant affect on immunohistochemical findings when studying angiogenesis. One also must use caution when comparing studies in the literature that use different techniques and reagents.

A comparison of survival models for assessing risk of racehorse fatality

Survival analysis was used to assess risk factors for fatal injuries on UK race courses. This allowed assessment of variation due to temporal horse-level effects, including previous racing intensity and historical distribution of race types, as well as race-level factors. Comparisons were made between measuring survival time as number of days and as number of races to injury from the first race. Two related models were presented for time as number of races to injury: a Cox regression model fitted using partial likelihood, with the Efron approximation to handling ties, and a discrete-time logit model fitted using maximum likelihood. The latter approach had the advantages of being computationally more efficient and enabling the testing of different functional forms for the dependence of hazard on time. Retrospective data were available from all race starts on the 59 courses in Britain from 1990 to the end of 1999, as analysed by . The analysis was conducted on the data for the 47,424 horses that had started racing in the UK: 538,895 starts with 1,228 fatal injuries. Horses starting racing abroad were excluded, but some included horses would have raced abroad at some stage during their racing career. The results for the selected models were broadly consistent with each other and with previously published studies. Steeplechase and hurdle races had a higher risk of fatal injury than flat races (relative hazards 1.5 and 1.7, respectively). Risk increased with the firmness of surface, age and race distance (reaching a plateau at 20 furlongs) and decreased with previous racing intensity (reaching a plateau after seven races run in the last 12 months). Horses running their first race of a new type were also found to be at higher risk (relative hazard 1.5). The main difference between the models for time as number of days and number of races concerned the role of age: age at race was identified as the more important factor in the latter model, whereas, age at first race was more significant in the former model.

Second messengers regulate RGS2 expression which is targeted to the nucleus

Regulators of G-protein Signaling (RGS) proteins attenuate signaling activities of G proteins, and modulation of expression appears to be a primary mechanism for regulating RGS proteins. In human astrocytoma 1321N1 cells RGS2 expression was increased by activation of muscarinic receptors coupled to phosphoinositide signaling with carbachol, or by increased cyclic AMP production, demonstrating that both signaling systems can increase the expression of a RGS family member in a single cell type. Carbachol-stimulated increases in endogenous RGS2 protein levels appeared by immunocytochemical analysis to be largely confined to the nucleus, and this localization was confirmed by Western blot analysis which showed increased nuclear, but not cytosolic, RGS2 after carbachol treatment. Additionally, transiently expressed green fluorescent protein (GFP)-tagged, 6xHis-tagged, or unmodified RGS2 resulted in a predominant nuclear localization, as well as a distinct accumulation of RGS2 along the plasma membrane. The intranuclear localization of GFP-RGS2 was confirmed with confocal microscopy. Thus, RGS2 expression is rapidly and transiently increased by phosphoinositide signaling and by cyclic AMP, and endogenous and transfected RGS2 is largely, although not entirely, localized in the nucleus.

Oxidative stress and heat shock stimulate RGS2 expression in 1321N1 astrocytoma cells

RGS2, a regulators of G-protein signaling family member, regulates G-protein signaling and is itself controlled in part by regulated expression. We tested if cell stress regulates RGS2 expression in human astrocytoma 1321N1 cells. Treatment with H2O2 increased RGS2 mRNA levels time- and concentration-dependently, with 200 microM H2O2 causing an approximately eightfold increase after 2 h. Peroxynitrite and heat shock also increased RGS2 mRNA levels. H2O2-induced RGS2 expression was negatively regulated by phosphoinositide-3-kinase and extracellular signal-regulated kinases. H2O2 also concentration-dependently increased RGS2 protein levels, and the RGS2 appeared to be predominantly in the nucleus. These results demonstrate that RGS2 expression is up-regulated by cell stress.

HuR, a RNA stability factor, is expressed in malignant brain tumors and binds to adenine- and uridine-rich elements within the 3' untranslated regions of cytokine and angiogenic factor mRNAs

Tumors of the central nervous system (CNS) often have sustained expression of labile genes, including angiogenic growth factors and immunosuppressive cytokines, which promote tumor progression. Stabilization of the RNA transcripts for these genes, such as vascular endothelial growth factor (VEGF), is an important molecular pathway for this up-regulation. HuR, a member of the Elav family of RNA-binding proteins, has been implicated in this pathway through its binding to adenine and uridine (AU)-rich stability elements (ARE) located in the 3' untranslated regions (3'-UTRs) of the mRNA. Whereas three of the Elav family members (Hel-N1, HuC, and HuD) are restricted to young and mature neurons, HuR is more broadly expressed, including proliferating cells of the developing CNS. Because RNA stabilization of labile genes may promote tumor growth, we analyzed and compared the expression pattern of HuR in 35 freshly resected and cultured CNS tumors to determine whether there was any correlation with tumor grade or histological type. We found that HuR mRNA was consistently expressed in all of the tumors, regardless of cell origin or degree of malignancy. Using a novel HuR-specific polyclonal antibody, we found that strong HuR protein expression was limited to high-grade malignancies (glioblastoma multiforme and medulloblastoma). Within the glioblastoma multiforme, prominent HuR expression was also detected in perinecrotic areas in which angiogenic growth factors are up-regulated. To further define its role as a potential RNA stabilizer, we analyzed whether HuR could bind to the stability motifs within the 3'-UTRs of cytokines and growth factors linked to brain tumor progression. We used a novel ELISA-based RNA binding assay and focused on the 3'-UTRs of angiogenic factors VEGF, COX-2, and (interleukin) IL-8 as well as the immunomodulating factors IL-6, transforming growth factor (TGF)-beta and tumor necrosis factor (TNF)-alpha as potential RNA ligands. Our results indicated overall a very high binding affinity to these RNA targets. A comparison of these ligands revealed a hierarchy of binding affinities with the angiogenic factors, and TGF-beta showing the highest (Kd of 1.8-3.4 nM), and TNF-alpha the lowest (Kd of 18.3 nM). The expression pattern of HuR, coupled with the RNA binding data, strongly suggests a role for this protein in the posttranscriptional regulation of these genes in CNS tumors.

HIV+ patients have increased lymphocyte infiltrates in CIN lesions

OBJECTIVE

The objective of our study was to analyze immunocyte infiltrates in CIN lesions from HIV+ patients to assess whether local immunosuppression, defined as a decrease in T cell infiltrates, could explain the aggressive nature of CIN in HIV-infected patients.

MATERIALS AND METHODS

Cervical tissue was obtained from 6 HIV+ CIN patients, 6 HIV- CIN patients, who underwent LLETZ (large loop excision of the transformation zone) for CIN, and 17 normal patients who underwent hysterectomy for benign indications. The following cell surface markers were analyzed: CD20 (B cells), CD4 (T helper cells), and CD8 (T suppressor/cytotoxic cells). Each tissue section was visualized with a Leica microscope at 400x and the image was captured for analysis by Harmony Group image analysis software.

RESULTS

A significantly higher number of lymphocytes (both B and T cells) was detected in the stroma of HIV+/CIN tissue compared to either HIV-/CIN or normal tissue. There was also a significant increase in CD8+ cells in the HIV+/CIN group compared to HIV-/CIN or normal tissue. There was a trend toward a decreased CD4+/CD8+ ratio in the HIV+/CIN compared to the other two groups; however, this did not reach statistical significance.

CONCLUSIONS

This study indicates that HIV+/CIN cervical tissue has a greater number of tissue lymphocytes recruited to the neoplastic site compared to HIV- individuals. In addition, HIV+ patients may have a decreased CD4/CD8 ratio in locally infiltrating immunocytes in CIN lesions. The local immunomodulatory effects of HIV may be detectable early in infection and therefore may explain the aggressive nature of CIN in the HIV+ patient.

Are women more ready to consult than men? Gender differences in family practitioner consultation for common chronic conditions

BACKGROUND

When consultations for all reasons are combined, women are seen to consult their general practitioners more than men through most of adult life. It is, therefore, often assumed that women are more likely to consult for every condition.

OBJECTIVES

To examine whether women report being more likely to consult a general practitioner than men when taking account of the underlying condition and various aspects of the experience of the condition consulted for.

METHODS

Home-based nurse-interviews with 852 people in early middle age (39 years) and 858 in late middle age (58 years) sampled from the general population in the West of Scotland. Detailed information about current chronic conditions included general practitioner consultation and reported experience of pain frequency, pain severity, limitation to normal activities and restricted activity in the previous four weeks.

RESULTS

Women were no more likely than men to consult a general practitioner in the previous year when experiencing the five most common groups of conditions; in addition, women were no more likely than men to consult at a given level of severity for a given condition type, except in the case of one aspect of reported experience of mental health problems.

CONCLUSIONS

The results argue against the most widely accepted explanation for gender differences in consulting, namely, that women are simply more likely to consult a general practitioner than men irrespective of underlying morbidity. Reasons for the higher rates of women consulting observed in general practice-based studies are discussed in relation to these data.

Loss of bcl-2 expression in ductal carcinoma in situ of the breast relates to poor histological differentiation and to expression of p53 and c-erbB-2 proteins

AIM

This study (1) investigates the incidence of bcl-2 protein expression in a series of 108 cases of ductal carcinoma in situ (DCIS), including 25 with early invasive carcinoma, and (2) evaluates the relationship of bcl-2 expression to the histological grade of DCIS and to the expression of oestrogen receptor (ER), c-erbB-2 and p53 proteins.

METHODS AND RESULTS

The expression of bcl-2, oestrogen receptor (ER), c-erbB-2 and p53 proteins was determined immunohistochemically. Cases were regarded as positive for individual antibodies when at least 10% of the DCIS cells showed positive staining. DCIS was graded histologically as well (n = 9), intermediately (n = 24), or poorly differentiated (n = 75). bcl-2 expression was documented in 57 cases (53%) and was strongly associated with the histological grade of DCIS (P < 0.0001). All cases of well-differentiated DCIS were bcl-2 positive and loss of bcl-2 expression was almost exclusively confined to poorly differentiated DCIS lesions. bcl-2 expression was also closely associated with positive ER status (P < 0.0001). Forty-seven of 57 (82%) bcl-2 positive cases were ER positive while 49/51 (96%) bcl-2 negative cases were ER negative. There was a significant inverse correlation between bcl-2 expression and both p53 protein expression (P = 0.0004) and c-erbB-2 expression (P < 0.0001). Nineteen of 24 (79%) p53 positive cases and 38/45 (84%) c-erbB-2 positive cases showed loss of bcl-2.

CONCLUSIONS

Loss of bcl-2 expression occurs in poorly differentiated DCIS and is related to negative ER status and to positive p53 and c-erbB-2 status. This pattern of bcl-2 expression and its association with other biological markers in DCIS is similar to that reported in invasive breast carcinoma.