Health resource use and costs of symptomatic knee and/or hip osteoarthritis.

BACKGROUND: Data on the economic consequences of hip and knee osteoarthritis (OA) are scarce. We aimed to estimate the annual direct and indirect costs for patients followed for hip and/or knee OA in the Knee and Hip Osteoarthritis Long term Assessment (KHOALA) cohort. METHODS: The KHOALA cohort, set up from 2007 to 2009, is a French multicenter study of 878 individuals with symptomatic knee/hip OA who were 40-75 years old. Resources used were collected annually for 5 years. Costs were assigned by using official sources and expressed in 2018 euros per patient. RESULTS: The mean annual total costs per patient over the 5-year study period were 2,180 ± 5,305€. The mean annual direct medical costs per patient were 2,120 ± 5,275€ and mean annual indirect costs per patient 180 ± 1,735€ for people of working age. Costs increased slightly over the study period. Drugs were the largest cost share, representing over 50% of all direct costs. However, the proportion attributable to OA drugs accounted for only 10.5% of drug costs. The second cost share was hospitalizations; hip and knee prosthetic surgery accounted for 27% of surgery hospitalization costs. Health professional visits were the third cost share, accounting for 3% of direct medical costs. The median costs induced could be as high as 2 billion €/year (IQR 0.7-4.3) in France. CONCLUSION: Hip and knee OA costs were substantial and increased over the study period in France. However, the costs attributable to OA represented only a small fraction of overall costs.

Economic impact of lower-limb osteoarthritis worldwide: a systematic review of cost-of-illness studies.

OBJECTIVE: An overview of the economic consequences - overall costs as well as cost breakdown (direct and indirect) - of hip and knee osteoarthritis (OA) worldwide. METHODS: A systematic literature search of EMBASE, MEDLINE, Scopus and Cochrane databases for articles was performed independently by two rheumatologists who used the same predefined eligible criteria. Papers without abstracts and in languages other than English or French were excluded. Extracted costs were converted to an annual cost and to 2013 euros (€) by using the Consumer Price Index of the relevant countries and the 2013 Purchasing Power Parities between these countries and the European Union average. RESULTS: A total of 45 abstracts were selected, and 32 articles were considered for the review. The studied populations were heterogeneous: administrative, hospital and national health survey data. Annual total costs per patient ranged from 0.7 to 12 k€, direct costs per patient from 0.5 to 10.9 k€ and indirect costs per patient from 0.2 to 12.3 k€. The weighted average annual costs per patient living with knee and hip OA were 11.1, 9.5 and 4.4 k€ for total, direct and indirect costs, respectively. CONCLUSIONS: This review highlights the heterogeneity of studies and lack of methodologic consensus to obtain reliable cost-of-illness estimates for lower-limb OA. However, costs induced by the disease seem substantial and deserve to be more extensively explored.

Response shift effects on measuring post-operative quality of life among breast cancer patients: a multicenter cohort study.

PURPOSE: To characterize response shift effects in patients with breast cancer (BC). METHODS: The QLQ-C30, BR23, and EurQOL-EQ-5D were assessed at baseline and at the end of the first hospitalization. We used the then-test approach to characterize changes in internal standards by calculating the mean difference between the then-test (retrospective measure) and pre-test baseline QoL assessments. The Ideal Scale Approach was also used to assess changes in standards by comparing health and QoL expectancies between baseline and the end of the first hospitalization. Successive Comparison Approach was used to assess changes in values through the longitudinal assessment of the relative importance of EuroQOL dimensions. RESULTS: The results of this study showed that recalibration RS effects occurred early after the first hospitalization for 6/15 dimensions of QLQ-C30 (emotional, cognitive, fatigue, insomnia, appetite loss, diarrhea) and 2/8 of BR-23 (future perspective, systemic therapy side effects). Moreover, health and QoL expectancies changed between the baseline and the end of the first hospitalization, and changes in values were seen for the self-care and usual activities dimensions of the EuroQOL-EQ-5D. CONCLUSIONS: The occurrence of RS early after the first hospitalization suggests that it needs to be taken into account to interpret QoL changes in BC.

Six-month outcome of elderly people hospitalized via the emergency department: the SAFES cohort.

BACKGROUND: The objective of the study was to identify factors predictive of 6-month institutionalization or mortality in frail elderly patients after acute hospitalization. METHODS: A prospective cohort of elderly subjects 75 years and older was set up in nine French teaching hospitals. Data obtained from a comprehensive geriatric assessment were used in a Cox model to predict 6-month institutionalization or mortality. Institutionalization was defined as incident admission either to a nursing home or other long-term care facility during the follow-up period. RESULTS: Crude institutionalization and death rates after 6 months of follow-up were 18% and 24%, respectively. Independent predictors of institutionalization were: living alone (HR=1.83; 95% CI=1.27-2.62) or a higher number of children (HR=0.86; 95% CI=0.78-0.96), balance problems (HR=1.72; 95% CI=1.19-2.47), malnutrition or risk thereof (HR=1.93; 95% CI=1.24-3.01), and dementia syndrome (HR=1.88; 95% CI=1.32-2.67). Factors found to be independently related to 6-month mortality were exclusively medical factors: malnutrition or risk thereof (HR=1.92; 95% CI=1.17-3.16), delirium (HR=1.80; 95% CI=1.24-2.62), and a high level of comorbidity (HR=1.62; 95% CI=1.09-2.40). Institutionalization (HR=1.92; 95% CI=1.37-2.71) and unplanned readmission (HR=4.47; 95% CI=3.16-2.71) within the follow-up period were also found as independent predictors. CONCLUSION: The main factors predictive of 6-month outcome identified in this study are modifiable by global and multidisciplinary interventions. Their early identification and management would make it possible to modify frail elderly subjects' prognosis favorably.

Expression of a retrovirus encoding human HPRT in mice.

Transmissible retroviruses encoding human hypoxanthine phosphoribosyltransferase (HPRT) were used to infect mouse bone marrow cells in vitro, and the infected cells were transplanted into mice. Both active human HPRT-protein and chronic HPRT-virus production were detected in hematopoietic tissue of the mice, showing transfer of the gene. These results indicate the possible use of retroviruses for somatic cell therapy.

Retroviral vector-mediated gene transfer into human hematopoietic progenitor cells.

The transfer of the human gene for hypoxanthine phosphoribosyltransferase (HPRT) into human bone marrow cells was accomplished by use of a retroviral vector. The cells were infected in vitro with a replication-incompetent murine retroviral vector that carried and expressed a mutant HPRT complementary DNA. The infected cells were superinfected with a helper virus and maintained in long-term culture. The production of progeny HPRT virus by the bone marrow cells was demonstrated with a colony formation assay on cultured HPRT-deficient, ouabain-resistant murine fibroblasts. Hematopoietic progenitor cells able to form colonies of granulocytes or macrophages (or both) in semisolid medium in the presence of colony stimulating factor were present in the nonadherent cell population. Colony forming units cloned in agar and subsequently cultured in liquid medium produced progeny HPRT virus, indicating infection of this class of hematopoietic progenitor cell.

A brief review of radiation hormesis.

This paper reviews physical, experimental and epidemiological evidence for and against radiation hormesis and discusses implications with regards to radiation protection. The scientific community is still divided on the premise of radiation hormesis, with new literature published on a regular basis. The International Commission on Radiological Protection (ICRP) recommends the use of the Linear No Threshold (LNT) model, for planning radiation protection. This model states that the probability of induced cancer and hereditary effects increases with dose in a linear fashion. As a consequence, all radiation exposures must be justified and have a sufficient protection standard in place so that exposures are kept below certain dose limitations. The LNT model has sufficient evidence at high doses but has been extrapolated in a linear fashion to low dose regions with much less scientific evidence. Much experimentation has suggested discrepancies of this extrapolation at low doses. The hypothesis of radiation hormesis suggests low dose radiation is beneficial to the irradiated cell and organism. There is definite standing ground for the hormesis hypothesis both evolutionarily and biophysically, but experimental evidence is yet to change official policies on this matter. Application of the LNT model has important radiation protection and general human health ramifications, and thus it is important that the matter be resolved.

Derivation and validation of a mortality-risk index from a cohort of frail elderly patients hospitalised in medical wards via emergencies: the SAFES study.

To identify predictive factors for 2-year mortality in frail elderly patients after acute hospitalisation, and from these to derive and validate a Mortality Risk Index (MRI). A prospective cohort of elderly patients was set up in nine teaching hospitals. This cohort was randomly split up into a derivation cohort (DC) of 870 subjects and a validation cohort (VC) of 436 subjects. Data obtained from a Comprehensive Geriatric Assessment were used in a Cox model to predict 2-year mortality and to identify risk groups for mortality. A ROC analysis was performed to explore the validity of the MRI. Five factors were identified and weighted using hazard ratios to construct the MRI: age 85 or over (1 point), dependence for the ADL (1 point), delirium (2 points), malnutrition risk (2 points), and co-morbidity level (2 points for medium level, 3 points for high level). Three risk groups were identified according to the MRI. Mortality rates increased significantly across risk groups in both cohorts. In the DC, mortality rates were: 20.8% in the low-risk group, 49.6% in the medium-risk group, and 62.1% in the high-risk group. In the VC, mortality rates were respectively 21.7, 48.5, and 65.4%. The area under the ROC curve for overall score was statistically the same in the DC (0.72) as in the VC (0.71). The proposed MRI appears as a simple and easy-to-use tool developed from relevant geriatric variables. Its accuracy is good and the validation procedure gives a good stability of results.

Predicting early mortality among elderly patients hospitalised in medical wards via emergency department: the SAFES cohort study.

OBJECTIVES: The aim of the study was, by early identification of deleterious prognostic factors that are open to remediation, to be in a position to assign elderly patients to different mortality risk groups to improve management. DESIGN: Prospective multicentre cohort. SETTING: Nine French teaching hospitals. PARTICIPANTS: One thousand three hundred and six (1 306) patients aged 75 and over, hospitalised after having passed through Emergency Department (ED). MEASUREMENTS: Patients were assessed using Comprehensive Geriatric Assessment (CGA) tools. A Cox survival analysis was performed to identify prognostic variables for six-week mortality. Receiver Operating Characteristics analysis was used to study the discriminant power of the model. A mortality risk score is proposed to define three risk groups for six-week mortality. RESULTS: Crude mortality rate after a six week follow-up was 10.6% (n=135). Prognostic factors identified were: malnutrition risk (HR=2.1; 95% CI: 1.1-3.8; p=.02), delirium (HR=1.7; 95% CI: 1.2-2.5; p=.006), and dependency: moderate dependency (HR=4.9; 95% CI: 1.5-16.5; p=.01) or severe dependency (HR=10.3; 95% CI: 3.2-33.1; p < .001). The discriminant power of the model was good: the c-statistic representing the area under the curve was 0.71 (95% IC: 0.67 - 0.75; p < .001). The six-week mortality rate increased significantly (p < .001) across the three risk groups: 1.1% (n=269; 95% CI=0.5-1.7) in the lowest risk group, 11.1% (n=854; 95% CI=9.4-12.9) in the intermediate risk group, and 22.4% (n=125; 95% CI=20.1-24.7) in the highest risk group. CONCLUSIONS: A simple score has been calculated (using only three variables from the CGA) and a practical schedule proposed to characterise patients according to the degree of mortality risk. Each of these three variables (malnutrition risk, delirium, and dependency) identified as independent prognostic factors can lead to a targeted therapeutic option to prevent early mortality.

Proliferation induced by keratinocyte growth factor enhances in vivo retroviral-mediated gene transfer to mouse hepatocytes.

Retroviral gene transfer to liver without prior injury has not yet been accomplished. We hypothesized that recombinant human keratinocyte growth factor would stimulate proliferation of hepatocytes and allow for efficient in vivo gene transfer with high titer murine Moloney retroviral vectors. This report shows that 48 h after intravenous injection of keratinocyte growth factor, hepatocyte proliferation increased approximately 40-fold compared to non-stimulated livers. When keratinocyte growth factor treatment was followed by intravenous injection of high titer (1 x 10(8) colony forming units/ml) retrovirus coding for the Escherichia Coli beta-galactosidase gene, there was a 600-fold increase in beta-galactosidase expression, with 2% of hepatocytes transduced. Thus, by exploiting the mitogenic properties of keratinocyte growth factor, retrovirus-mediated gene transfer to liver may be accomplished in vivo without the use of partial hepatectomy or pretreatment with other toxins to induce hepatocyte cell division.

Feline immunodeficiency virus vectors persistently transduce nondividing airway epithelia and correct the cystic fibrosis defect.

Several problems limit the application of gene transfer to correct the cystic fibrosis (CF) Cl(-) transport defect in airway epithelia. These include inefficient transduction with vectors applied to the apical surface, a low rate of division by airway epithelial cells, failure of transgene expression to persist, and immune responses to vectors or vector-encoded proteins. To address these issues, we used a feline immunodeficiency virus-based (FIV-based) vector. FIV vector formulated with a calcium chelator transduced fully differentiated, nondividing human airway epithelia when applied to the apical surface. FIV-based vector encoding the cystic fibrosis transmembrane conductance regulator cDNA corrected the Cl(-) transport defect in differentiated CF airway epithelia for the life of the culture (>3 months). When this approach was applied in vivo, FIV vector expressing beta-galactosidase transduced 1-14% of adult rabbit airway epithelia. Transduced cells were present in the conducting airways, bronchioles, and alveoli. Importantly, gene expression persisted, and cells with progenitor capacity were targeted. FIV-based lentiviral vectors may be useful for the treatment of genetic lung diseases such as CF. This article may have been published online in advance of the print edition.

Variable stability of a selectable provirus after retroviral vector gene transfer into human cells.

Human lymphoblasts deficient in the enzyme hypoxanthine-guanine phosphoribosyltransferase (HPRT) were infected with an amphotropic helper-free retroviral vector expressing human HPRT cDNA. The stability and expression of the HPRT provirus in five cell lines with different proviral integration sites were examined by determining HPRT mutation and reversion frequencies and by blot hybridization studies. Mutation to the HPRT-negative phenotype occurred at frequencies of approximately 4 X 10(-5) to 3 X 10(-6) per generation. Most mutations in each of the five cell lines were associated with partial or complete deletions or rearrangements of the provirus. Several mutants retained a grossly intact HPRT provirus, and in one such mutant HPRT shutdown resulted from a revertible epigenetic mechanism that was not associated with global changes in proviral methylation. Therefore, mutation and shutdown of the HPRT provirus in human lymphoblasts result from mechanisms similar to those reported for several other avian and mammalian replication-competent retroviruses.

Screening for frailty in community-dwelling elderly subjects: Predictive validity of the modified SEGA instrument.

AIMS: To study the capacity of the SEGAm instrument to predict loss of independence among elderly community-dwelling subjects. METHODS: The study was performed in four French departments (Ardennes, Marne, Meurthe-et-Moselle, Meuse). Subjects aged 65 years or more, living at home, who could read and understand French, with a degree of autonomy corresponding to groups 5 or 6 in the AGGIR autonomy evaluation scale were included. Assessment included demographic characteristics, comprehensive geriatric assessment, and the SEGAm instrument at baseline. Subjects had follow-up visits at home at 6 and 12 months. During follow-up, vital status and level of independence were recorded. Logistic regression was used to study predictive validity of the SEGAm instrument. RESULTS: Among the 116 subjects with complete follow-up, 84 (72.4%) were classed as not very frail at baseline, 23 (19.8%) as frail, and 9 (7.8%) as very frail; 63 (54.3%) suffered loss of at least one ADL or IADL at 12 months. By multivariable analysis, frailty status at baseline was significantly associated with loss of independence during the 12 months of follow-up (OR=4.52, 95% CI=1.40-14.68; p=0.01). We previously validated the SEGAm instrument in terms of feasibility, acceptability, internal structure validity, reliability, and discriminant validity. CONCLUSIONS: This instrument appears to be a suitable tool for screening frailty among community-dwelling elderly subjects, and could be used as a basis to plan early targeted interventions for subjects at risk of adverse outcome.

[Request of epidural analgesia by women and obstetrical teams in four French areas. Part I: Request for analgesia]. / Demande d'analgésie périmédullaire par les patientes et les équipes obstétricales dans quatre régions françaises. Partie I : demande d'analgésie.

OBJECTIVE: Epidural analgesia (EA) is widely used in France to treat the labour pain. The aim of this study was to evaluate and analyse the reasons of EA requirements by parturients and obstetricians. STUDY DESIGN: An epidemiological survey was sent in all maternity units of four French areas. PATIENTS AND METHODS: Forty-eight of the 84 maternity units entered the study. In each centre, 25 patients fulfilled the questionnaire and the medical team fulfilled a questionnaire about the organisation of the ward. Demands of EA by parturients during pregnancy, labour and for the next delivery were recorded, and also the offer of EA by midwives and the possibility to move in an other town to obtain an EA. Student t-test, chi2 test and logistic regression model were used as requested. p<0.05 was considered as significant. RESULTS: One thousand one hundred forty-two women entered the study. During pregnancy 79% of women asked for an EA, they were 72% during labour. Factors influencing the request of an EA were parity, educational level, pain, preanaesthetic evaluation and the size and the kind of maternity unit (university, public or private hospital). During labour, the request of an EA was more frequent when anaesthesiologists were on call in the hospital (77.7 vs 66.7%, p<0.001). Midwives offered EA to 69% of women. For the next delivery 79.9% of women hoped an EA, the factors of this new request were parity, pain during this labour and EA during this labour; 42.8% would be ready to move in an other town to obtain an EA. The medical indications for EA occurred in 1.8% of patients. DISCUSSION: The request for EA mainly comes from women. Probably, in France, the request for EA will not diminish in the future. Analgesia networks could be considered.

[Request of epidural analgesia by women and obstetrical teams in four French areas. Part II: Management of epidural analgesia]. / Demande d'analgésie périmédullaire par les patientes et les équipes obstétricales dans quatre régions françaises. Partie II : réalisation des analgésies périmédullaires.

OBJECTIVE: Epidural analgesia (EA) is widely used in France to treat the labour pain. The aim of this study was to evaluate and analyse the rate of EA and the ratio between EA required by parturients and total EA realised (performance ratio). STUDY DESIGN: An epidemiological survey was sent in all maternity units of 4 French areas. Patients and methods. - 48 of the 84 maternity units were participating to the study. In each centre, 25 patients fulfilled the questionnaire and the medical team fulfilled a questionnaire about the organisation of the ward. Rate of EA and performance ratio were calculated. Student t test, chi2 test and logistic regression model were used as requested; p<0.05 was considered as significant. RESULTS: The mean rate of epidural analgesia (EA) rate, in the French areas studied, was 61.6%. It was significantly higher in university (79+/-13.7%) and private hospital (73.1+/-20.4%) than in general hospitals (54.6+/-19.6%, p<0.01), and also in those where anaesthesiologists are dedicated to the maternity unit (71.3+/-17.8 vs 54.6+/-22.1%, p<0.01) and in hospitals where anaesthesiologists were on duty in the hospital versus on call at home (69.8+/-21.4 vs 56.1+/-19%, p<0.02). Median duration of EA was 180 minutes, and 21.3% of them lasted more than five hours. Most of EA was performed between 8 AM and 6 PM. Patients' request was the major reason of EA insertion (OR=11.81), then the midwife request (OR=9.01). Other significant factors were the type of the hospital, the anaesthesiologist on duty and parity of women. The ratio between the number of EA requested by parturients and the total number of EA performed was significantly better in university hospitals (100.3+/-13%) and private hospitals (92.2+/-15.7%) than in general hospitals (79.4+/-17.3%, p<0.02). For the patients who had requested EA and did not have EA, the main reason was that labour was too fast (122/167) and then that there was a fail in anaesthesiological organization (59/167). The contraindications were rare (14/167). CONCLUSION: To correctly answer to the request of EA, it seems necessary that one or more anaesthesiologists were dedicated to the maternity units, and that they were on duty into the hospital. So it seems important to have large maternities with adequate number of anaesthesiologists.

HIV protease as a target for retrovirus vector-mediated gene therapy.

The dimeric aspartyl protease of HIV has been the subject of intense research for almost a decade. Knowledge of the substrate specificity and catalytic mechanism of this enzyme initially guided the development of several potent peptidomimetic small molecule inhibitors. More recently, the solution of the HIV protease structure led to the structure-based design of improved peptidomimetic and non-peptidomimetic antiviral compounds. Despite the qualified success of these inhibitors, the high mutation rate associated with RNA viruses continues to hamper the long-term clinical efficacy of HIV protease inhibitors. The dimeric nature of the viral protease has been conducive to the investigation of dominant-negative inhibitors of the enzyme. Some of these inhibitors are defective protease monomers that interact with functional monomers to form inactive protease heterodimers. An advantage of macromolecular inhibitors as compared to small-molecule inhibitors is the increased surface area of interaction between the inhibitor and the target gene product. Point mutations that preserve enzyme activity but confer resistance to small-molecule inhibitors are less likely to have an adverse effect on macromolecular interactions. The use of efficient retrovirus vectors has facilitated the delivery of these macromolecular inhibitors to primary human lymphocytes. The vector-transduced cells were less susceptible to HIV infection in vitro, and showed similar levels of protection compared to other macromolecular inhibitors of HIV replication, such as RevM10. These preliminary results encourage the further development of dominant-negative HIV protease inhibitors as a gene therapy-based antiviral strategy.

Predictors of Long-Term Mortality in Oldest Old Patients (90+) Hospitalized to Medical Wards via the Emergency Department: The SAFES Cohort.

OBJECTIVES: To identify risk factors for long-term mortality in patients aged 90 years and over who are admitted to hospital through the emergency department. DESIGN: Prospective cohort study (SAFES cohort; Sujet Agé Fragile - Évaluation Suivi). SETTING: 8 university teaching hospitals and one regional, non-academic hospital in France. PARTICIPANTS: Among 1306 patients in the SAFES cohort, 291 patients aged 90 or over were included. MEASUREMENTS: At inclusion, we recorded socio-demographic data (age, sex, level of education, living alone or in an institution, number of children, presence of helper/caregiver), and data from geriatric evaluation (dependence status, risk of depression, dementia, delirium, nutritional status, walking disorders, risk of falls, comorbidities, risk of pressure sores). Vital status at 36 months was obtained from the treating physician, the general practitioner, administrative registers, or during follow-up consultations. RESULTS: Among 291 patients included, 190 (65.3%) had died at 36 months. Risk factors for mortality at 36 months identified by multivariate analysis were risk of malnutrition (HR 1.6, 95%CI 1.1-2.3, p=0.004) and delirium (HR 1.6, 95%CI 1.1-2.3, p=0.01). CONCLUSION: Risk of malnutrition and presence of delirium are risk factors for mortality at 36 months in subjects aged 90 years and over hospitalized through the emergency department.

Cytotoxic T-lymphocyte induction in asymptomatic HIV-1-infected patients immunized with Retrovector-transduced autologous fibroblasts expressing HIV-1IIIB Env/Rev proteins.

OBJECTIVE: To demonstrate the safety and enhancement of HIV-1-specific immune responses in HIV-infected asymptomatic patients following treatment with retroviral vector (Retrovector)-transduced autologous fibroblasts (VTAF) expressing HIV-1IIIB Env/Rev proteins. DESIGN: A non-placebo-controlled, single arm Phase I study. PARTICIPANTS: Four HIV-1-seropositive asymptomatic volunteers were selected based on age (18-50 years), CD4/CD3 lymphocyte counts (> 600 x 10(6)/l or > 40%), and positive delayed-type hypersensitivity test to at least one recall antigen. INTERVENTIONS: Patients were treated at 2-week intervals with a total of three intramuscular injections of irradiated autologous fibroblasts transduced with a molecularly engineered, non-replicating amphotropic murine retrovector encoding the HIV-1IIIB Env/Rev proteins. MAIN OUTCOME MEASURES: The clinical status of patients was assessed by history, physical examination, serum chemistry and hematology, CD4/CD3 lymphocyte counts, HIV viral burden, and monitored throughout the study to detect potentially treatment-induced toxic or unwanted side-effects. In addition, HIV-1-specific cytotoxic T-lymphocyte (CTL) activity was measured to determine the biological activity of VTAF. RESULTS: No acute local or systemic adverse events occurred following three injections with VTAF. Furthermore, a statistically significant increase of CD8+ CTL activity against HIV-1IIIB Env/Rev-expressing targets was observed in peripheral blood mononuclear cells from two out of four patients. CONCLUSIONS: This is the first report of the administration of a gene transfer treatment to HIV-1-infected patients and provides initial support for the safety and activity of retrovector-transduced fibroblasts administered to asymptomatic patients. This treatment resulted in the detection of increased HIV-1IIIB Env/Rev-specific CTL activity in two HIV-seropositive patients and could provide a better understanding of the role of CTL activity in HIV disease progression.

Recombinant retroviral vector delivered intramuscularly localizes to the site of injection in mice.

A murine retroviral vector encoding the human immunodeficiency virus type 1 (HIV-1) env and rev genes can be used to induce cytotoxic T lymphocyte responses. Immune responses can be induced by an ex vivo treatment, in which autologous cells are transduced in vitro and re-introduced to the donor, or by direct administration of retroviral vector via intramuscular injection. In this study we have used polymerase chain reaction (PCR) analysis to examine the distribution of recombinant murine retrovirus directly administered to mice. Mice were injected intramuscularly with HIV-IT(V), an amphotropic murine leukemia virus (MLV)-based retroviral vector carrying the HIV-1 env/rev genes and a neomycin resistance marker gene. Detection of the HIV-1 env gene in DNA isolated from injection sites demonstrated in vivo transduction. No evidence of transduction was observed in the testes, spleen, kidney, or thymus. Retroviral DNA was detected in the liver of one animal in the study. These data suggest that retroviral vector administered intramuscularly to mice localizes primarily to the site of injection and that measurable transduction in the testes does not occur.

Alveolar macrophages inhibit retrovirus-mediated gene transfer to airway epithelia.

Gene transfer with integrating vectors such as recombinant retrovirus has the potential to correct inherited lung diseases permanently. As a gene therapy target, the pulmonary epithelium presents several challenges to vector delivery in vivo. Many of the host defenses that have evolved to prevent infection from inhaled bacteria or viruses represent potential barriers to gene transfer to the lung. We performed in vitro studies to determine whether two components of the innate immune system of the lung, airway surface fluid and alveolar macrophages, inhibit retroviral gene transfer to airway epithelia. Human alveolar macrophages obtained by bronchoalveolar lavage from normal subjects were left untreated or activated with lipopolysaccharide (LPS) for 3 hr in the presence of subconfluent human bronchial epithelial cells (HBE); than 4 x 10(5) cfu DA-luciferase retrovirus was added. Three days after infection, luciferase activity was measured in cell lysates. When the epithelial cells were co-cultured with LPS-activated macrophages, retroviral gene transfer to HBE cells was reduced by approximately 60%. Nonactivated macrophages decreased the transfection to approximately 55% of control values. In control experiments with either activated or inactivated macrophages but without epithelia, no luciferase activity was detected, suggesting that terminally differentiated alveolar macrophages are not infected by the recombinant retrovirus. Pretreatment of alveolar macrophages with dexamethasone restored gene transfer to approximately 60% of control values. In contrast, incubation of retrovirus with airway surface fluid had no inhibitory effect on gene transfer. These experiments document that AM inhibit retrovirus-mediated gene transfer to airway epithelia in vitro, and may represent a barrier to retroviral gene transfer in vivo. These barriers may be overcome, at least partially, with pharmacological agents.