John D. Shanley

Augmentation of graft-versus-host reaction by cytomegalovirus infection resulting in interstitial pneumonitis

The severity of the graft-versus-host (GVH) reaction, judged by splenomegaly and immunosuppression, was augmented by murine cytomegalovirus (MCMV) infection. Profound GVH-induced immunosuppression was seen in adult unirradiated MCMV-infected F1, mice even after challenge with extremely low doses of parental spleen cells. Mice receiving MCMV+GVH challenge died from days 16–21, with interstitial pneumonia being the most prominent pathological lesion. Pulmonary disease was unrelated to levels of viral replication in the lung. These results suggest that in human marrow recipients, cytomegalovirus infection may play a primary role both in provoking or accentuating GVH disease, as well as in the development of interstitial pneumonia.

Modification by Adoptive Humoral Immunity of Murine Cytomegalovirus Infection

The effects of specific antiviral antibody on several aspects of infection with murine cytomegalovirus (CMV) were examined. Administration of immune serum 24 hr before subcutaneous inoculation of 10(5) plaque-forming units of murine CMV prevented detectable viral replication in the tissues of 92% of animals. Protection was associated with the immune globulin fraction and not with normal serum or heterologous antiviral serum. However, the development of latent murine CMV infection was not prevented by prior administration of antibody since immunosuppression with antilymphocyte serum and cortisone 16 weeks later unmasked dormant virus in 17 of 20 animals. In normal animals murine CMV-immune serum administered six days after acute virus infection had been initiated did not influence the outcome; however, in immunosuppressed mice, virus dissemination during acute infection was substantially reduced by specific antibody. These results demonstrate a significant effect of humoral immunity on the course of experimental CMV infection.

Mucosal immunization with a replication-deficient adenovirus vector expressing murine cytomegalovirus glycoprotein B induces mucosal and systemic immunity

The murine cytomegalovirus (MCMV) glycoprotein B (gB) gene was expressed in an adenovirus replication-deficient vector. This virus, designated Ad-gB, was used to immunize BALB/c and B6 mice by the intranasal (i.n.) route to induce an immune response. Following primary immunization, antibody was detected in serum of 100% of vaccinees, as well as the bronchoalveolar lavage, fecal suspensions and vaginal washings. The viral titer of lung and salivary gland of vaccinees 10 days after intranasal challenge with MCMV at 10(5) or 10(3)plaque forming units (PFU) were significantly reduced compared to controls. Re-exposure of vaccinees to Ad-gB 30 days after primary immunization induced a remarkable boost of serum and mucosal antibody responses and further reduction of MCMV titers in the lung and salivary glands. The ability to induce both a systemic and mucosal immune response to a specific gene product may be important in reducing horizontal transmission of CMV infections across mucosal surfaces and in altering host immunity to CMV.

Interstitial pneumonitis during murine cytomegalovirus infection and graft-versus-host reaction: characterization of bronchoalveolar lavage cells

Acute murine cytomegalovirus (MCMV) infection alters the course of graft-vs-host (GVH) disease involving major histocompatibility (MHC) antigens and induces interstitial pneumonitis. F1 (B10×B10.BR) mice given 20 × 105 B10.BR spleen cells and MCMV (1 × 105 plaque-forming units [PFU]) develop severe, diffuse pneumonitis not seen with either MCMV or GVH alone. As one index of the host immune processes operating in the lungs during MCMV/GVH pneumonitis, we examined the types of cells recovered from the lung by bronchoalveolar lavage (BAL) during pneumonitis. During MCMV/GVH pneumonitis, the total cells recovered significantly increased, due primarily to an influx of Thy 1.2 lymphocytes. Characterization of cells using multi-parameter flow cytometric analysis revealed that >80% of all BAL cells were Thy 1.2-positive lymphocytes of donor origin. In addition, donor Thy 1.2-positive cells were of both the L3T4+ (43% of BAL cells) and Lyt 2+ (38% of BAL cells) phenotype. Thus, MCMV infection during GVH to MHC antigens induces interstitial pneumonitis, characterized by an influx of T lymphocytes …

ALTERED THRESHOLD FOR THE INDUCTION OF GRAFT-VERSUS-HOST IMMUNODEFICIENCY FOLLOWING MURINE CYTOMEGALOVIRUS INFECTION HOST AND DONOR CONTRIBUTIONS

Acute murine cytomegalovirus (MCMV) infection enhances the ability of parental spleen cells to induce graft-vs.-host immunodeficiency (GVHID) in F1 hybrid mice when the two processes occur simultaneously in the recipient. The present study assessed GVHID as the ability of spleen cells to generate in vitro cytotoxic T lymphocyte responses to trinitrophenyl-modified syngeneic cells. The results indicate that MCMV infection not only reduces the number of parental spleen cells required to induce GVHID, but accelerates the onset of GVHID, which occurs as early as 3 days after cell and virus challenge. To determine whether MCMV infection exerts this synergistic effect primarily through the donor or the host component, we examined the effect of MCMV infection of either donor mice or recipient mice at 3, 10, and 17 days prior to spleen cell transfer. Two weeks after cell transfer, splenocytes were tested for their ability to generate CTL. When donor mice were infected with MCMV three days prior to cell transfer, the ability of donor cells to induce GVHID was reduced. In contrast, MCMV infection of the recipients three days prior to cell transfer increased their susceptibility to GVHID induction. Infection of either donor or host mice 10 days or 17 days prior to parental spleen cell transfer had little effect on the ability to induce or resist GVHID when compared with sham-infected mice. Thus, acute MCMV infection can modulate the severity of GVHID depending on whether it is the donor or the host that is infected. The ability of acute MCMV to alter the course and severity of GVHID may be relevant for human bone marrow transplants in which preceding CMV infection has been associated with chronic GVH. In this setting, CMV may lower the threshold necessary to induce a GVH reaction.

ASPD Blunts the Effects of HIV and Antiretroviral Treatment on Event-Related Brain Potentials

Several studies have demonstrated that antiretroviral therapy diminishes the adverse effects of HIV/AIDS on brain function. Yet, few studies have examined the role of comorbid psychiatric disorders in limiting the magnitude of recovery. The present study examined the effects of the presence versus absence of one such disorder – antisocial personality disorder (ASPD) – on brain function in an HIV-1 seronegative control group (n = 68) and in HIV-1 seropositive patients receiving (n = 26), versus not receiving (n = 71), antiretroviral treatment. The primary dependent measures of brain function were the amplitude, latency, and topography of the P300 event-related potential. ANCOVA revealed a significant main effect of ASPD as well as an interaction between ASPD and HIV-1/treatment status. Participants with ASPD exhibited a significant decrement in frontal P300 amplitude in comparison to the ASPD-negative groups. More importantly, further analyses showed that ASPD blunted the decrement in P300 accompanying untreated HIV/AIDS as well as the improvement in P300 accompanying antiretroviral treatment. The results suggest that P300 is minimally improved by antiretroviral therapy among HIV-1 seropositive patients with comorbid ASPD. The lack of antiretroviral efficacy is not easily explained by poor medication compliance. The diminished response to treatment is more likely related to a pre-existing neurophysiological decrement localized to the same brain regions where HIV/AIDS and antiretroviral treatment exert their maximal effect.

Characterization of a 52K protein of murine cytomegalovirus and its immunological cross-reactivity with the DNA-binding protein ICP36 of human cytomegalovirus

We have developed a hybridoma, designated 25G11, which produced a monoclonal antibody (MAb) reactive with a 52K protein of murine cytomegalovirus (MCMV). This MAb, 25G11, was reactive with a protein band of 52K in MCMV-infected cell lysates and with a protein of 49K in human CMV (HCMV)-infected cell lysates as detected by immunoblot analysis. With purified MCMV virions, 25G11 gave a faintly immunoreactive band of 52K. However, no immunoreactive protein band was detected with purified HCMV virions, nor with purified HCMV or MCMV envelope preparations. By immunocytochemistry, 25G11 detected viral antigen primarily in the nucleus of HCMV- or MCMV-infected cells. The antibody 25G11 was used to screen a lambda gt11 library of HCMV DNA fragments. One of the isolated clones (lambda 32323B) was employed for gene mapping on the HCMV genome, which suggested that the immunoreactive HCMV protein was the DNA-binding protein (ICP36). Analysis of the recombinant fusion protein with antibody 25G11 and with an MAb (CH16) specific for an HCMV DNA-binding protein confirmed the identity of the cross-reacting protein as ICP36. Furthermore, we found that whereas the epitope recognized by 25G11 was conserved between HCMV and MCMV proteins, the epitope recognized by CH16 was unique to HCMV and thus represents a variable region in the protein.

Sensorimotor Dysfunction in HIV/AIDS: Effects of Antiretroviral Treatment and Comorbid Psychiatric Disorders

Objectives:Balance and gait problems have repeatedly been mentioned in case descriptions of patients infected with Human Immunodeficiency Virus (HIV-1). Objective evidence of these problems has rarely been reported, however. Furthermore, the extent to which balance and gait are influenced by antiretroviral medications or comorbid psychiatric disorders has rarely been examined. Design:The study compared 78 HIV-1 seronegative volunteers to 28 HIV/AIDS patients receiving no antiretroviral therapy, 25 patients receiving only nucleoside analogue therapy, and 37 patients receiving Highly Active Antiretroviral Therapy (HAART). Methods:The dependent measures included Equilibrium Quotient scores recorded during 3 subtests of the Sensory Organization Test (SOT), the number of falls during each subtest, the functional base of support, gait speed and cadence, single leg balance time, proximal strength, and vibrotactile threshold of the foot. The analysis employed the number of alcohol and drug abuse problems, depression severity, and body mass index as covariates. Results:ANCOVAs revealed significant decrements in the 3 HIV-1 seropositive groups relative to the control group on Equilibrium Quotient scores during the most difficult of the SOT subtests (sway-referenced support surface with eyes-closed). HIV/AIDS patients also exhibited a smaller functional base of support and greater vibrotactile thresholds. Antiretroviral treatment did not affect balance; but, it did alter sensory threshold in a complex manner. Conclusions:HIV/AIDS is associated with reliable decrements in balance and peripheral sensory function which are variably sensitive to antiretroviral treatment. The implications of these findings for mobility, and workplace or operator safety, should be contemplated.

Host Genetic Factors Influence Murine Cytomegalovirus Lung Infection and Interstitial Pneumonitis

We evaluated the influence of host genetic factors on the course of murine cytomegalovirus (MCMV) lung infection after intranasal inoculation and on the development of interstitial pneumonitis after virus and cyclophosphamide (CP) administration. Susceptibility to virus replication in the lungs of various inbred murine strains was inherited as an autosomal dominant trait, which was associated with the H-2 locus. Similarly, the development of MCMV interstitial pneumonitis was inherited as an autosomal dominant, polygenic trait. Susceptibility to lung infection was necessary, but not sufficient for MCMV interstitial pneumonitis. Non-H-2-associated factors were also needed and probably related to CP metabolism or the character of immune recovery after CP administration. Therefore, inheritable host factors influence both susceptibility to MCMV lung infection and the genesis of MCMV interstitial pneumonitis.

Murine Cytomegalovirus Influences Foxj1 Expression, Ciliogenesis, and Mucus Plugging in Mice with Allergic Airway Disease

We have followed throughout time the development of allergic airway disease (AAD) in both uninfected mice and mice infected intranasally with murine cytomegalovirus (MCMV). Histological evaluation of lung tissue from uninfected mice with AAD demonstrated mucus plugging after 14 and 21 days of ovalbumin-aerosol challenge, with resolution of mucus plugging occurring by 42 days. In MCMV/AAD mice, mucus plugging was observed after 7 days of ovalbumin-aerosol challenge and remained present at 42 days. The level of interleukin-13 in bronchoalveolar lavage fluid from MCMV/AAD mice was decreased compared with AAD mice and was accompanied by increased levels of interferon-gamma. Levels of Muc5A/C, Muc5B, or Muc2 mucin mRNA in the lungs of MCMV/AAD mice were not elevated compared with AAD mice. MCMV was able to infect the airway epithelium, resulting in decreased expression of Foxj1, a transcription factor critical for ciliogenesis, and a loss of ciliated epithelial cells. In addition, an increase in the number of epithelial cells staining positive for periodic acid-Schiff was observed in MCMV/AAD airways. Together, these findings suggest that MCMV infection of the airway epithelium enhances goblet cell metaplasia and diminishes efficient mucociliary clearance in mice with AAD, resulting in increased mucus plugging.