Early events following murine gammaherpesvirus (MHV-68) infection

Murine gammaherpesvirus (MHV-68) was isolated from a bank vole. It has pathobiological and genetic similarities to other gammaherpesviruses including Herpesvirus saimiri, Epstein-Barr virus (EBV) and Kaposi's sarcoma-associated herpesvirus (KSHV). It infects laboratory mice and forms plaques on cell monolayers in tissue culture. The pathogenesis and immunology have been widely studied in the mouse system and it has been identified as a useful "small animal model".Mice were infected with 4xl0⁵ PFU MHV-68 intranasally. The virus infects alveolar epithelial cells and causes interstitial pneumonia. In the lungs the virus undergoes lytic replication which is cleared by day 10. Subsequently the virus is found latent in B cells that have been found to be important in the establishment of latency and in the transmission of virus from the lungs to the spleen. The spleen and the lymph nodes at this stage exhibit splenomegaly and lymphadenopathy respectively. In B cell deficient (μMT) mice, latently infected cells are not detected in the spleen and splenomegaly is not observed.In this study, the early events following MHV-68 infection in vivo were examined. The work focused on the mediastinal lymph node (MEN) that drains the lungs. Events occurring in the MLNs from the wild type C57BL/6 mice were compared to those of the pMT mice. The results demonstrated the absence of lymphadenopathy in pMT mice and indicated that lymphadenopathy in wild type C57BL/6 mice was brought about especially by the accumulation of B cells. Depletion of CD4+ T cells in wild type C57BL/6 mice demonstrated that the absence of CD4+ T cells only partially affected the accumulation of B cells and enlargement of the MLN. The pMT mouse showed the presence of latent virus in the MLN even in the absence of B cells. However by day 10 these cells were below levels of detection and there was no evidence of systemic transfer of virus

Managing mood disorders in patients attending pulmonary rehabilitation clinics

Background: There is good evidence for the positive benefits of pulmonary rehabilitation (PR) in the prevention of hospital admissions, lower mortality, and improved health-related quality of life. There is also increasing evidence about the impact of PR on mental health and, in particular, mood disorders. We aimed to identify how depression in chronic obstructive pulmonary disease (COPD) patients in Victoria, Australia, is being managed in PR, to identify the prevalence of depressive symptoms among COPD patients who attend PR, and to determine whether patients with depressive symptoms or anxiety symptoms dropped out of PR early. Method: Of 61 PR clinics, 44 were invited and 22 agreed to participate. Telephone interviews were conducted to see how depression and anxiety in COPD patients were being recognized and managed in these clinics. A total of 294 questionnaires were distributed to patients by clinic coordinators to determine the prevalence of anxiety/depression, as measured by the Hospital Anxiety and Depression Scale. Coordinators were contacted to provide information on whether respondents dropped out of rehabilitation early or continued with their treatment at 2–4 months post program. Results: Seven clinics were not aware of local guidelines on assessment/treatment/management of mood. Four clinics did not use any screening tools or other aids in the recognition and management of depression and/or anxiety. Overall, eight clinics participating in this study requested advice on suitable screening tools. The patient survey indicated that the mean depression score on the Hospital Anxiety and Depression Scale was 5.0 (standard deviation 3.0, range 1–13). The mean anxiety score was 5.5 (standard deviation 3.4, range 0–18). There was no evidence of a link between failure to complete rehabilitation and depression or anxiety scores, as only three of 105 patients failed to complete their rehabilitation. Discussion: Awareness of management guidelines for depression and anxiety in COPD patients was variable across the clinics recruited into our study. We found no link between compliance with rehabilitation and depression, but our sample had limitations. Conclusion: Future research needs to investigate how best to encourage more use of available guidelines regarding integrating psychological and psychosocial support to supplement the exercise and education that are currently offered routinely by all PR clinics studied in Victoria, Australia

Development and Evaluation of an Enzyme-Linked Immunosorbent Assay for Dengue Capsid

The astonishing speed with which Dengue has spread across the world and the severity of its infection make Dengue a prime threat to human life worldwide. Unfortunately, to date there are no effective vaccines or treatments against Dengue. Since only a few assays permit rapid and sensitive detection of Dengue, we developed a specific antigen capture enzyme-linked immunosorbent assay (ELISA) for the abundant structural Dengue-2 capsid protein. We showed that the ELISA allows rapid and sensitive detection of Dengue-2 replication in various cell lines including human and mosquito cells. Using anti-capsid antibodies, we demonstrated that the capsid ELISA is as accurate as other well-characterized Dengue assays such as intracellular FACS staining (IFSA) and fluorescent focus (FFA) assays. The capsid ELISA not only represents a useful tool for in vitro basic research, but it may also represent a valuable diagnostic tool for Dengue infection in patients

A Neutralizing Monoclonal Antibody Targeting the Acid-Sensitive Region in Chikungunya Virus E2 Protects from Disease.

The mosquito-borne alphavirus, chikungunya virus (CHIKV), has recently reemerged, producing the largest epidemic ever recorded for this virus, with up to 6.5 million cases of acute and chronic rheumatic disease. There are currently no licensed vaccines for CHIKV and current anti-inflammatory drug treatment is often inadequate. Here we describe the isolation and characterization of two human monoclonal antibodies, C9 and E8, from CHIKV infected and recovered individuals. C9 was determined to be a potent virus neutralizing antibody and a biosensor antibody binding study demonstrated it recognized residues on intact CHIKV VLPs. Shotgun mutagenesis alanine scanning of 98 percent of the residues in the E1 and E2 glycoproteins of CHIKV envelope showed that the epitope bound by C9 included amino-acid 162 in the acid-sensitive region (ASR) of the CHIKV E2 glycoprotein. The ASR is critical for the rearrangement of CHIKV E2 during fusion and viral entry into host cells, and we predict that C9 prevents these events from occurring. When used prophylactically in a CHIKV mouse model, C9 completely protected against CHIKV viremia and arthritis. We also observed that when administered therapeutically at 8 or 18 hours post-CHIKV challenge, C9 gave 100% protection in a pathogenic mouse model. Given that targeting this novel neutralizing epitope in E2 can potently protect both in vitro and in vivo, it is likely to be an important region both for future antibody and vaccine-based interventions against CHIKV

The relationship between apathy and participation in therapeutic activities in nursing home residents with dementia: Evidence for an association and directions for further research

Apathy is one of the most frequent and early symptoms of dementia. Because apathy is characterised by lack of initiative and motivation, it leads to considerable burden being placed on carers to ensure that the person living with dementia has a reasonable quality of life. The aim of this study was to investigate the relationship between apathy and participation in therapeutic activities for older people with dementia living in nursing homes. Ninety residents were recruited into the study, and apathy was measured by nursing home staff using the Apathy Evaluation Scale Clinician version. Staff also compiled data on each resident’s involvement in therapeutic activities. Among this sample, the mean age was 84.8 years, and mean length of stay in the nursing home was 1.8 years. The mean apathy score was 50.4, indicating that on average the residents had a moderate level of apathy. Overall, residents participated in six activities per week and those residents who were involved in the most activities had the lowest levels of apathy. This paper provides evidence that residents involved in therapeutic activities have lower levels of apathy. Further research should be conducted on the direction of causality, whether apathy levels can be changed through participation in therapeutic activities, the relationship between dementia severity and modifiability of apathy, and the intensity of therapeutic activities required to maintain functioning

Comparing Antigenicity and Immunogenicity of Engineered gp120

We have engineered monomeric gp120 in such a way as to favorably present the conserved epitope for the broadly neutralizing antibody b12 while lowering the exposure of epitopes recognized by some weakly neutralizing and nonneutralizing antibodies. The work presented here describes the immune response in rabbits immunized with two prototype, engineered gp120s to explore the relationship between antigenicity and immunogenicity for these mutants. The GDMR gp120 mutant (residues 473 to 476 on gp120 altered from GDMR to AAAA) has a series of substitutions on the edge of the CD4 binding site (CD4bs), and the mCHO gp120 mutant has seven extra glycans relative to the wild-type protein. Importantly, serum mapping showed that both mutants did not elicit antibodies against a number of epitopes that had been targeted for dampening. The sera from rabbits immunized with the GDMR gp120 mutant neutralized some primary viruses at levels somewhat better than the wild-type gp120 immune sera as a result of an increased elicitation of anti-V3 antibodies. Unlike wild-type gp120 immune sera, GDMR gp120 immune sera failed to neutralize HXBc2, a T-cell line adapted (TCLA) virus. This was associated with loss of CD4bs/CD4-induced antibodies that neutralize TCLA but not primary viruses. The mCHO gp120 immune sera did not neutralize primary viruses to any significant degree, reflecting the masking of epitopes of even weakly neutralizing antibodies without eliciting b12-like antibodies. These results show that antibody responses to multiple epitopes on gp120 can be dampened. More precise focusing to a neutralizing epitope will likely require several iterations comparing antigenicity and immunogenicity of engineered proteins