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Biomedical subjects

R B Moss

Publications and source records attributed to R B Moss.

At least 19 recordsLinked to original sources

Activation of eosinophils in the airways of lung transplantation patients.

UNLABELLED: Eosinophils are important inflammatory cells involved in liver and renal allograft rejection. The role of these cells is less well defined in lung allograft rejection. Eosinophils may be activated in lung rejection and release cytotoxic eosinophil cationic protein (ECP). Other states of disease in lung transplant recipients, such as cytomegalovirus (CMV) and bacterial infection, may also be associated with activated eosinophils. We postulated that ECP may be detectable and elevated in the airway lavage samples obtained from lung transplant patients and may contribute to disease pathogenesis. METHODS: Fifty BAL samples were collected from 38 lung transplant patients. Their most recent pulmonary function test results within 1 week of collection were noted. The samples were analyzed for the concentration of ECP, WBC count and differential cell count, and total protein level. The results were analyzed to identify the presence of disease or abnormal lung function associated with a positive ECP test. Student's t test was used and a p value of <0.05 was considered significant. RESULTS: We found that ECP levels were elevated in 36% (n=14) of the patients. Those patients with a positive test result were more likely to have acute rejection, CMV disease, or the presence of a cultured pathogen in BAL compared to patients with a negative test result (p<0.01). CONCLUSIONS: The presence of BAL ECP is associated with disease in lung transplant patients. Since ECP is directly cytotoxic, it may contribute to disease pathogenesis.

Adult

Effect of immunization with an inactivated gp120-depleted HIV-1 immunogen on beta-chemokine and cytokine production in subjects with HIV-1 infection.

OBJECTIVE: To measure beta-chemokine and cytokine production in HIV-1-infected subjects undergoing treatment with HIV-1 immunogen (REMUNE). DESIGN: Open label treatment study. METHODS: beta-Chemokine and cytokine production in peripheral blood mononuclear cell (PBMC) culture. RESULTS: Interferon-gamma production (p = 0.04) and lymphocyte proliferation (p = 0.001) to HIV-1 antigen-stimulated PBMCs increased after immunization with the HIV-1 immunogen. A correlation was demonstrated after immunization between HIV-1 antigen-stimulated lymphocyte proliferation and interferon-gamma levels (r = 0.53, p = 0.04). No significant change after immunization was seen for interleukin-4 production. A significant increase in mean levels of HIV-1 antigen-stimulated RANTES (i.e., regulated upon, activation normal T-cell expressed and secreted), was evident 1 month after immunization (p = 0.002) and remained elevated 3 months after immunization. RANTES production was decreased in CD8-depleted PBMC cultures. Mean serum HIV-1 RNA copy numbers and CD4 cell counts remained stable after immunization (p > 0.5). A correlation was demonstrated between HIV-1 antigen-stimulated interferon-gamma and RANTES production (r = 0.54, p = 0.002). CONCLUSIONS: This report describes an augmentation of beta-chemokines and TH1-type cytokines from PBMCs after immunization with the HIV-1 immunogen.

CD4 Lymphocyte Count

Cross-clade immune responses after immunization with a whole-killed gp120-depleted human immunodeficiency virus type-1 immunogen in incomplete Freund's adjuvant (HIV-1 immunogen, REMUNE) in human immunodeficiency virus type-1 seropositive subjects.

Lymphocyte proliferation responses to gp120-depleted HZ321 virus (clade A) antigen were compared to BAL human immunodeficiency virus (HIV) virus antigen (clade B) responses, clade E HIV virus antigen responses, and purified native p24 antigen responses in 15 human immunodeficiency virus type-1 (HIV-1) seropositive subjects immunized with a whole-killed inactivated gp120-depleted HIV-1 antigen in Incomplete Freund's adjuvant (HIV-1 immunogen, REMUNE). A significant increase in lymphocyte proliferation to HZ321 antigen was observed after immunization with the HIV-1 immunogen (p = 0.02). A strong association was demonstrated between the HIV-1 immunizing antigen, HZ321, and native p24 antigen responses (r = 0.80, p < 0.0001). Furthermore, a strong association in terms of proliferative responses was demonstrated between HZ321 virus (clade A) responses and BAL virus (clade B) (r = 0.95, p < 0.0001) and clade E virus antigen (r = 0.92, p < 0.0001). Proliferative responses to HIV antigens also correlated with baseline CD4 counts. Taken together, these results support the specificity of immune responses induced by REMUNE (HIV-1 immunogen). The development of cross-reactive immune responses between clades and to the more conserved epitopes of the virus have implications in the development of therapeutic and prophylactic HIV vaccines.

AIDS Vaccines

Microsporidium-associated sinusitis.

Two cases of biopsy-proven Microsporidium-associated chronic sinusitis in HIV-seropositive patients are presented. Spores of Septata intestinalis were identified by light microscopy and confirmed by electron microscopy in each case. Both patients displayed severe deficiencies of nasal mucosa CD4-positive cells, demonstrated by immunohistochemical methods. Only two other cases of Septata intestinalis-associated sinusitis have been reported previously. Our observations agree with the theory that functional defects in local mucosal immunity may partially explain the acquisition of opportunistic mucosal infections in many HIV-seropositive patients.

AIDS-Related Opportunistic Infections

Constitutive mRNA and immunoreactivity for IL-2 in human nasal mucosa.

BACKGROUND: The nasal mucosa is the initial site in the upper airway of host defence against antigenic challenge in the form of airborne allergens, irritants, toxins and infectious agents, and yet little is known about nasal mucosal cytokine expression and function. We hypothesized that IL-2 might play a role in immunocompetence of the upper airway. METHODS: IL-2 immunoreactivity was measured by ELISA in nasal secretions and by Western blot. Immunohistochemistry and electron microscopy were performed on turbinated tissue. mRNA for IL-2 was evaluated by RTPCR and Southern hybridization. RESULTS: IL-2 immunoreactivity was demonstrated by Western blot and quantitated by an enzyme immunoassay. Immunohistochemical and electron microscopy analysis of turbinate tissue revealed interstitial staining for IL-2. By RTPCR, IL-2 message was evident in 5/5 atopics and 5/5 non-atopics. IL-2 message was expressed in all subjects by Southern hybridization to an internal probe after PCR. CONCLUSION: This study has demonstrated constitutive expression of IL-2 protein and mRNA in the upper airway of healthy individuals. The further characterization of cytokines in the upper airway could provide useful insights into immune regulation at the mucosal level.

Base Sequence

Early clinical markers and CD4 percentage in subjects with human immunodeficiency virus infection.

In a clinical trial involving asymptomatic, HIV-seropositive subjects treated with either the HIV-1 immunogen (an inactivated, gp120-depleted HIV-1 virus in incomplete Freund's adjuvant) or an adjuvant control, we examined the relationship between changes in the percentage of CD4 cells over time and early clinical markers of HIV disease progression. Subjects who had an early clinical event were more likely to have a greater decline in the percentage of CD4 cells than those subjects who did not have a clinical event (p = 0.054). The greatest decline in CD4 percentage occurred within 10 weeks prior to a clinical event (mean 11% decrease from baseline). Subjects from the quartile with the greatest decline in CD4 percentage had a fivefold greater risk of having a clinical event than subjects from the quartile with the second largest decline (p = 0.045). These results demonstrate a relationship between changes in the percentage of CD4 cells and early clinical events. Further validation of this association may be useful in clinical monitoring and in evaluating therapies to treat HIV infection.

AIDS Dementia Complex

Nasal mucosal cells in human immunodeficiency virus type 1-seropositive patients with sinusitis.

Recently, sinusitis has been recognized as a frequent clinical problem in human immunodeficiency virus (HIV-1)-infected individuals. We hypothesized that quantitative defects in immune cells in the nasal mucosa of HIV-positive subjects might mirror those in the peripheral blood and explain a predisposition to sinus disease in this population. Nasal mucosa biopsies were obtained from three different groups of patients-HIV-1 seropositive with sinusitis, HIV-1 seronegative with sinusitis, and HIV-1 seronegative without sinusitis (normal volunteer)-and phenotyped for cluster of differentiation antigen (CD) markers. In this study, we found patients with HIV-1 and sinus disease to have significantly lower numbers of both CD3 and CD4 nasal mucosa lymphocytes than seronegative controls in the nasal mucosa (P < 0.05, P < 0.01, respectively). A correlation between nasal mucosal CD4 cells and peripheral-blood CD4 cells was noted (R = 0.67, P < or = 0.01). No deficiency in the number of nasal mucosa T or TC type mast cells was noted for the HIV-1-positive sinusitis group. Further study is warranted to define more completely the pathophysiology and microbiology of, and therapy for, this important clinical problem.

Acquired Immunodeficiency Syndrome

Viral load, CD4 percentage, and delayed-type hypersensitivity in subjects receiving the HIV-1 immunogen and antiviral drug therapy.

Two trials of subjects inoculated with the inactivated, gp120-depleted HIV-1 Immunogen are reported. In one study, in which 19 subjects received ZDV and 8 subjects received ddI, treatment with the HIV-1 Immunogen did not affect the pharmacokinetic parameters of the antiviral drugs. In another study, 65 subjects who were previously immunized with the HIV-1 Immunogen over a mean period of 4.0 years (range, 1.2-5.4 years) received inoculations at 0 and 6 months. At some point during this 48-week study, 72% of the subjects (47/65) were receiving antiviral drug therapy. The HIV-1 DNA load in CD4 cells and CD4 percentage were found to be stable over the 48-week period. Delayed-type hypersensitivity to HIV-1 antigens increased after two inoculations with the HIV-1 Immunogen. In these two trials, no serious treatment-related adverse events were documented in the subjects. The two studies presented herein are the first to suggest that an immune-based therapy such as the HIV-1 Immunogen can be combined safely with antiviral drugs, supporting further study to evaluate the clinical utility of this approach.

AIDS Vaccines

Reduced IL-10 secretion by CD4+ T lymphocytes expressing mutant cystic fibrosis transmembrane conductance regulator (CFTR).

Expression of the CFTR protein is thought to be physiologically important only in exocrine epithelial cells. However, chronic respiratory inflammation and infection remain unexplained phenomena in disease pathogenesis. Non-transformed, antigen-responsive CD4+ T cells cloned from healthy controls and CF patients homozygous or heterozygous for the delta F508 mutation transcribed CFTR mRNA and expressed immunoreactive cytoplasmic CFTR protein. T cell clones (TCC) from controls and CF patients displayed equivalent Ca(2+)-mediated Cl- current; however, TCC from patients with CF but not controls displayed defective cAMP-mediated Cl-current. Although CF-derived TCC preserved mitogen and antigen proliferative responses and specificity to tetanus toxoid epitopes, they selectively secreted approximately 45% less IL-10 compared with control TCC after activation with concanavalin A (Con A) (624 +/- 101 versus 1564 +/- 401 pg/ml per 10(6) cells, respectively; P = 0.04) or anti-CD3/phorbol ester (5148 +/- 1634 versus 11788 +/- 2390 pg/ml; P = 0.05). This difference was independent of atopy. Secretion of interferon-gamma, IL-2, and IL-4 was comparable in CF and control TCC after both forms of activation, while IL-5 was reduced in CF TCC following anti-CD3/phorbol myristate acetate (PMA) but not after Con A. We conclude that expression of mutant CFTR in human TCC is accompanied by ion channel dysfunction characteristic of the CF phenotype, and is accompanied by a reduction in IL-10 secretion after polyclonal activation. It is possible that disruption of IL-10-mediated anti-inflammatory homeostasis may contribute to early onset sustained inflammation in CF airways.

Animals

Correlates of osteopenia in patients with cystic fibrosis.

OBJECTIVE: As the expected survival improves for individuals with cystic fibrosis, these individuals face myriad medical complications. The goals of this study were to examine the prevalence of osteopenia in children and adults with cystic fibrosis and to elucidate the risk factors associated with deficits in bone mineral. METHODOLOGY: We compared bone mineral levels in 49 patients (30 female and 19 male) ages 8 through 48 years with those of age- and sex-matched control subjects. Lumbar spine, femoral neck, and whole-body bone mineral were measured by dual-energy radiographic absorptiometry and expressed in terms of bone mineral content, areal bone density (BMD), and bone mineral apparent density (BMAD), which corrects for differences in bone size. Clinical variables were evaluated as potential correlates of bone mineral. RESULTS: Patients with cystic fibrosis had significantly less bone mineral than did control subjects at all sites using all expressions of bone mass. Mean BMD z scores were -1.7 (lumbar spine), -1.9 (femoral neck), and -1.2 (whole body). BMAD z scores also were significantly low for age and gender. Twenty-six of the 49 patients (8 adolescents) had significant osteopenia according to their BMD z scores; 14 of the 45 patients (5 adolescents) with available BMAD z scores had significantly low values at one or more sites. Age, pubertal stage, body mass, caloric expenditure, illness severity, glucocorticoid therapy, and gonadal function predicted bone mineral status. Serum parathyroid hormone and calcium, carbohydrate intake, and weight-bearing activity had limited predictive value. Daily calcium intake and cystic fibrosis transmembrane regulator genotype did not predict bone mineral status. CONCLUSIONS: Osteopenia is common at all ages in cystic fibrosis, suggesting that inadequate bone mineral accretion as well as increased bone loss contribute to the deficits in bone mineral observed. Several clinical factors seem to contribute to these deficits.

Absorptiometry, Photon

Activation of CFTR chloride current by nitric oxide in human T lymphocytes.

Nitric oxide, which is produced by cytokine-activated mononuclear cells, is thought to play an important role in inflammation and immunity. While the function of nitric oxide as a direct cytotoxic effector molecule is well established, its function as a transducer molecule in immune cells is not. By use of whole-cell patch clamp recordings, we show that nitric oxide activates cystic fibrosis transmembrane conductance regulator CI- currents in normal human cloned T cells by a cGMP-dependent mechanism. This pathway is defective in cystic fibrosis-derived human cloned T cells. These findings not only delineate a novel transduction mechanism for nitric oxide but also support the hypothesis that an intrinsic immune defect may exist in cystic fibrosis.

Aminoquinolines

Management of sinusitis in cystic fibrosis by endoscopic surgery and serial antimicrobial lavage. Reduction in recurrence requiring surgery.

OBJECTIVE: An effective treatment program for refractory chronic sinusitis in patients with cystic fibrosis has not been achieved. We developed a long-term management approach by combining endoscopic surgery with serial antimicrobial lavage (ESSAL). DESIGN: In a before and after trial, results of ESSAL in 32 patients were compared with those of conventional sinus surgery without serial antimicrobial lavage in 19 patients. At least 1 year follow-up was available in all but one patient. SETTING AND PATIENTS: Patients attending the Stanford (Calif) Cystic Fibrosis Center were consecutively referred for otolaryngologic evaluation for symptoms and signs of refractory sinusitis. Those subjects who were evaluated before 1990 were treated conventionally and afterward by ESSAL. INTERVENTION: Conventionally treated patients underwent one or more of the following procedures: polypectomy, ethmoidectomy, antrostomy, or Caldwell-Luc operation. The ESSAL approach incorporated preoperative rhinosinuscopy and computed tomography, endoscopic surgery, a postoperative course of antral antimicrobial lavage, and monthly maintenance antimicrobial lavage via brief antral catheterization. MAIN OUTCOME MEASURE: Intensity and frequency of sinus surgery after initial presentation. RESULTS: The two groups were similar demographically and in clinical presentation, including the presence of nasal polyposis in 34% and 42%, respectively. The ESSAL group had fewer operations per patient, Caldwell-Luc procedures, and a decrease in repeated surgery at 1-year (10% vs 47%) and 2-year (22% vs 72%) follow-ups. CONCLUSION: The ESSAL is a successful approach to treatment of sinusitis in cystic fibrosis that reduces recurrence requiring further surgery for at least 2 years.

Adolescent

Viral load in peripheral blood mononuclear cells as surrogate for clinical progression.

During the symposium on surrogate markers of HIV, the Scientific Advisory Committee posed the following question: "Which surrogate markers currently deserve the greatest commitment of investigative resources to validate them in a clinical setting?" The Committee concluded that for antiretroviral drugs measurements of HIV RNA in plasma deserve the greatest priority, and for immune-based therapies assessing viral load still had the highest priority. But it was recognized that assessing viral load should not be restricted to plasma RNA because the primary mechanisms of action are different from antiretroviral drugs. Thus, the Committee voted that based on current knowledge, investigating the clinical relevance of changes in HIV-1 DNA and RNA copy number in peripheral blood mononuclear cells (PBMCs) with validated assays should be given equal focus for immune-based therapies. This article reviews the rationale for using HIV-1 DNA and RNA load in PBMCs for the monitoring of clinical trials and presents recent data that indicate that the postseroconversion level and the dissemination of proviral DNA in the blood cells have prognostic value, i.e., high levels correlate with disease progression. In addition, longitudinal studies show that an increase in proviral DNA and/or HIV mRNA load correlates with disease progression. We present evidence that these markers are relevant activity markers for anti-HIV therapies. Changes in both DNA and RNA load can be achieved using either antiretroviral drugs or immune-based therapies. These results suggest that these markers should be evaluated in clinical studies to firmly establish their value as surrogates of clinical progression.

Biomarkers

Safety and immunogenicity of a gp120-depleted, inactivated HIV-1 immunogen: results of a double-blind, adjuvant controlled trial.

We report the safety and immunogenicity results of a double-blind adjuvant controlled trial of the human immunodeficiency virus type 1 (HIV-1) immunogen. Healthy, asymptomatic HIV-1-seropositive individuals received either three 100 microgram doses of the inactivated HIV-1 antigen in incomplete Freund's adjuvant (IFA) or three doses of IFA alone. The results of this study show that this HIV-1 immunogen is safe, with mild and transient adverse events. No difference in the number or type of adverse events was noted between the treatment groups. Rises in HIV-1-specific humoral and cell-mediated immune (CMI) responses were also noted, favoring the HIV-1 immunogen-treated group. The results of this study confirm and extend the safety and immunogenicity profile of this HIV-1 immunotherapeutic agent. The observation that this treatment can augment HIV-1-specific CMI is encouraging because this immunological marker may represent a key surrogate end point in HIV-1 infection and disease.

AIDS Vaccines

Primed in situ DNA amplification (PIDA).

A novel PCR in situ protocol is described which can be implemented in one day. An initial amplification step with a single primer pair is followed by an amplification with an internal oligonucleotide probe with labeled nucleotides (dig-dUTP). Detection is then accomplished with an antidigoxigenin antibody and substrate solution. This rapid and sensitive method may be useful in diagnosing low copy DNA in tissue specimens and cells.

DNA, Viral