Anti-TGF-beta treatment prevents skin and lung fibrosis in murine sclerodermatous graft-versus-host disease: a model for human scleroderma.

Scleroderma, a debilitating acquired connective tissue disease, is characterized by fibrosis, particularly of the skin and lungs. Monocyte-produced TGF-beta1, a potent stimulus for collagen synthesis, is thought to drive the fibrosis. Here, we thoroughly characterize a murine sclerodermatous graft-vs-host disease (Scl GVHD) model for scleroderma that reproduces important features of scleroderma including skin thickening, lung fibrosis, and up-regulation of cutaneous collagen mRNA, which is preceded by monocyte infiltration and the up-regulation of cutaneous TGF-beta1 mRNA. Most importantly, we can prevent fibrosis in both the skin and lungs of mice with Scl GVHD by inhibiting TGF-beta with neutralizing Abs. The murine Scl GVHD model provides the unique opportunity to study basic immunologic mechanisms that drive fibrosing diseases and GVHD itself and will be useful for testing new therapies for these diseases.

Gamma 3 gene-disrupted mice selectively deficient in the dominant IgG subclass made to bacterial polysaccharides undergo normal isotype switching after immunization with polysaccharide-protein conjugate vaccines.

Bacterial polysaccharides (PS) are T-independent type 2 Ags that elicit restricted Ab responses of IgM and IgG3 in mice and IgM and predominantly IgG2 in humans. Immunodeficiency in the dominant IgG subclass made to PS is associated with chronic sinus and pulmonary infections with PS-encapsulated bacteria. To elucidate the biologic role of the dominant IgG subclass in the immune response to PS and to make an animal model of human IgG subclass deficiency, we generated mice with a targeted disruption of the exon encoding the CH1 domain of the gamma 3 heavy-chain constant region gene. Homozygotes had no detectable serum IgG3, and their splenocytes did not produce IgG3 after LPS stimulation. IgG3(-/-) mice immunized with PS from Pseudomonas aeruginosa LPS O-side chain or Streptococcus pneumoniae type 19F capsule did not produce any IgG3 anti-PS Abs, in contrast to wild-type mice in which IgG3 was the major IgG subclass. Immunizing both wild-type and IgG3(-/-) mice with 19F PS-protein conjugate elicited IgG1 Abs. We conclude that IgG3(-/-) mice have a selective deficiency in the dominant murine IgG subclass made to T-independent type 2 Ags and may be a useful animal model of IgG subclass deficiency. In addition, we show that the anti-PS Ab class switching to IgG1 that occurs when mice are immunized with a PS-protein conjugate vaccine does not require sequential Ig expression or an intact, upstream gamma 3 heavy-chain gene.

Mitogenic synthetic polynucleotides suppress the antibody response to a bacterial polysaccharide.

Unmethylated bacterial DNA containing a high frequency of the CpG motif, is mitogenic and induces T-cell independent, murine B-cell proliferation. These stimulatory effects are also induced by synthetic oligonucleotides that contain one or more unmethylated CpG dinucleotides (CpG oligo). Such mitogenicity is not seen with highly methylated vertebrate DNA, which has a lower prevalence of the CpG motif than bacterial DNA. Due to their stimulatory effects, CpG oligo have been proposed for use as vaccine adjuvants. In order to determine if a synthetic CpG oligo that was stimulatory for B-cell proliferation could augment the murine antibody response to protective bacterial polysaccharide epitopes (Pseudomonas aeruginosa LPS-O polysaccharide side chain; high-molecular-weight polysaccharide or high-MW PS), BALB/c mice were injected with mitogenic doses of CpG oligo simultaneously with high-MW PS, and antibody titers were measured by ELISA weekly for 4 weeks. Controls received PBS, a nonstimulatory control oligo plus PS, CpG alone, or PS alone. Despite evidence of B-cell mitogenicity and an increase in total IgM in CpG oligo-treated mice, CpG oligo treatment plus PS significantly decreased the high-MW PS antibody response compared to PS alone. The blunting of the anti-PS antibody response could be eliminated by vaccinating the animals with PS prior to CpG oligo. We conclude that despite in vitro and in vivo evidence of B-cell proliferation, this CpG oligo reduces PS-specific antibody responses in an animal model when given simultaneously with a bacterial polysaccharide. Based on results in this model, oligonucleotides containing stimulatory unmethylated CpG dinucleotides may not be useful adjuvants when given simultaneously with bacterial PS vaccines.

Bispecific antibodies overcome the opsonin-receptor mismatch of cystic fibrosis in vitro: restoration of neutrophil-mediated phagocytosis and killing of Pseudomonas aeruginosa.

Inflammation and infection associated with bacterial pathogens, primarily Pseudomonas aeruginosa (Pa), are the primary causes of morbidity and mortality for cystic fibrosis (CF) patients. CF patients may be predisposed to these bacterial infections by a defect in phagocytosis due to "opsonin-receptor mismatch," in which a complement receptor (CR1) and an important opsonin (iC3b) are destroyed by proteolytic enzymes. We show that opsonin-receptor mismatch can be mitigated in vitro using a bispecific Ab (bsAb) to cross-link neutrophils via the beta-chain of leukocyte integrins (CD18) to bacterial epitopes or C3d on opsonized Pa. Two chemically cross-linked bsAb were constructed with mAb specific for C3d (or the O-specific side chain of Fisher Devlin Immunotype 1 Pa) and CD18. Using an in vitro model of elastase-mediated opsonin-receptor mismatch, these bsAb specifically enhanced Pa phagocytosis and killing, with the anti-C3d-containing bsAb restoring the levels of phagocytosis to approximately those for the non-elastase-treated opsonic control. These results encourage the further investigation of bsAb as therapeutic agents for bacterial infection in the lungs of CF patients.

Community integration of former state hospital patients: outcomes of a policy shift in Vermont.

OBJECTIVE: The study examined the level of community integration achieved by patients discharged from the state hospital into the community in compliance with a regionalization policy in Vermont that sought to reduce the need for central hospitalization through expansion of community capacity. METHODS: The population in residence at the state hospital on August 30, 1989, was tracked longitudinally as patients were discharged into one of Vermont's ten catchment areas. Structured interviews about the current status of the discharged individuals were conducted four years later with case managers, nursing home personnel, and community care home operators. Service utilization and hospitalization data were obtained from the Vermont Department of Mental Health database. RESULTS: Of 122 patients in residence at the state hospital on the given date, 58 were discharged into the community, of whom 46 consented to participate in the study. At follow-up, about half lived in structured residential settings. Of the 46 followed, 87 percent were rehospitalized during the study period for periods ranging from three months to one year. Although participants had adequate levels of support both from within and outside the mental health system, their integration into the community was low in terms of their use of community resources, stigma-related problems, and difficulties gaining access to services. CONCLUSIONS: The regionalization policy accomplished some of its goals, especially those related to downsizing the state hospital, placing clients in community residential settings, and enhancing the range of community services. The more pervasive and insidious problems of community integration faced by consumers were not effectively mitigated by the policy.

A qualitative approach to assessing the effects of system change on consumers, families, and providers.

OBJECTIVE: In 1988 Vermont implemented a policy designed to reduce the state hospital census and expand community-based services. This qualitative study assessed perceptions of the policy's impact among mental health consumers, family members, and providers. METHODS: Eleven focus groups were convened, which included 94 participants from across the state. Separate groups were held for consumers, family members, and providers. Trained facilitators guided discussion of the policy's effect on quality of life, housing and vocational status, community integration, and social networks. Audiotapes of the discussion were transcribed, and content was analyzed. RESULTS: Several universal themes were noted. All participants reported that stigma was still a substantial barrier to integration and that community education to reduce stigma had not been effective. Tension between families and providers was a problem; family members felt that although providers depended on their supporting the consumer, they were not included in treatment planning. All participants noted that urban areas were better served by the policy's service packages. A lack of coordination of community services was reported to be a continuing problem across the state. In contrast to findings of previous studies, consumers in this study preferred not to live alone, which led to feelings of isolation. CONCLUSIONS: Service delivery in rural areas and system coordination throughout the state must be improved. Families' conflicting feelings of burden and isolation must be addressed. Further research should determine more clearly the range of housing preferences among consumers.

Group B streptococcus-induced nitric oxide production in murine macrophages is CR3 (CD11b/CD18) dependent.

Nitric oxide (NO) is produced by murine macrophages in response to cytokines and/or gram-negative bacterial lipopolysaccharide. NO induction by gram-positive bacteria such as group B streptococci (GBS), the major etiologic agents of neonatal pneumonia and meningitis, has received little study. GBS as well as two other gram-positive bacterial species, Staphylococcus aureus and Staphylococcus epidermidis, were found to stimulate NO production in thioglycolate-elicited murine macrophages and in the mouse macrophage cell line J774A.1 in the presence of gamma interferon. Serotype Ia and III GBS were both stimulatory, as were asialo- and type antigen-deficient mutant strains of type III GBS. NO production was dose dependent, inhibitable by L-arginine analogs, and unaffected by polymyxin B. Since phagocytosis by murine and human phagocytes of GBS is dependent on complement receptor type 3 (CR3), the role of CR3 in the NO response to GBS was tested in the CR3-deficient myelomonocytic cell line WEHI-3. GBS did not induce NO, whereas S. aureus or lipopolysaccharide did induce NO in WEHI-3 cells. S. epidermidis, whose nonopsonic phagocytosis is also CR3 dependent, failed to induce NO in WEHI-3 cells. Monoclonal anti-CR3 (anti-CD11b or anti-CD18) in the presence of interferon also induced NO production in thioglycolate-elicited macrophages and in J774A.1 cells but not in WEHI-3 cells. This evidence suggests that ligated CR3 and gamma interferon act synergistically to induce NO production and that CR3 mediates the GBS-induced signal for NO production in interferon-treated macrophages.

A study of provider perceptions of individuals with dual disorders.

Human service workers devote a great deal of time in preparing to serve clients. The majority of this preparation is focused in one direction, with exposure to a limited type of client. The growing population of individuals with dual disorders of mental illness and substance abuse challenges this tradition in training, in that these clients pose unique, multiple, and overlapping characteristics, symptomatology, and behaviors requiring a synthesis of training approaches. Based on survey data collected in a county in New York State, this study discusses how providers from various agencies view individuals with dual disorders and proposes coordination and training efforts that can be designed to respond to providers' treatment concerns.