Prevention of experimental autoimmune encephalomyelitis by antibodies against interleukin 12.

Experimental allergic encephalomyelitis (EAE) is an autoimmune disease of the central nervous system that can be transferred to naive mice via CD4+ T cells isolated from appropriately immunized mice. We have evaluated the effects of recombinant murine interleukin 12 (rmIL-12), a potent inducer of interferon gamma (IFN-gamma) and promoter of Th1 T cell development, on the course of adoptively transferred EAE. The transfer of lymph node cells (LNC) isolated from proteolipid protein (PLP)-primed animals and stimulated in vitro with PLP to naive mice resulted in a progressive paralytic disease culminating in complete hind limb paralysis in the majority of the recipients. When mice were injected with LNC that had been stimulated in vitro with PLP in the presence of rmIL-12, the subsequent course of disease was more severe and prolonged. The addition of rmIL-12 during the in vitro stimulation with PLP resulted in a 10-fold increase in IFN-gamma and a 2-fold increase in tumor necrosis factor (TNF) alpha in the supernatants, relative to LNC stimulated with PLP alone. However, neutralization of IFN-gamma or TNF-alpha in vitro with specific antibodies did not abrogate the ability of rmIL-12 to exacerbate the subsequent disease. Similarly, mice treated with rmIL-12 in vivo after the transfer of antigen-stimulated LNC developed a more severe and prolonged course of disease compared with vehicle-treated control animals. In contrast, treatment of mice with an antibody to murine IL-12 after cell transfer completely prevented paralysis, with only 40% of the mice developing mild disease. These results demonstrate that in vitro stimulation of antigen primed LNC with PLP and rmIL-12 enhances their subsequent encephalitogenicity. Furthermore, inhibition of endogenous IL-12 in vivo after LNC transfer prevented paralysis, suggesting that endogenous IL-12 plays a pivotal role in the pathogenesis of this model of autoimmune disease.

Resolution of cutaneous leishmaniasis: interleukin 12 initiates a protective T helper type 1 immune response.

Resistance to Leishmania major in mice is associated with the appearance of distinct T helper type 1 (Th1) and Th2 subsets. T cells from lymph nodes draining cutaneous lesions of resistant mice are primarily interferon gamma (IFN-gamma)-producing Th1 cells. In contrast, T cells from susceptible mice are principally Th2 cells that generate interleukin 4 (IL-4). Although existing evidence is supportive of a role for IFN-gamma in the generation of Th1 cells, additional factors may be required for a protective response to be maintained. A potential candidate is IL-12, a heterodimeric cytokine produced by monocytes and B cells that has multiple effects on T and natural killer cell function, including inducing IFN-gamma production. Using an experimental leishmanial model we have observed that daily intraperitoneal administration at the time of parasite challenge of either 0.33 micrograms IL-12 (a consecutive 5 d/wk for 5 wk) or 1.0 micrograms IL-12 per mouse (only a consecutive 5 d) caused a > 75% reduction in parasite burden at the site of infection, in highly susceptible BALB/c mice. Delay of treatment by 1 wk had less of a protective effect. Concomitant with these protective effects was an increase in IFN-gamma and a decrease in IL-4 production, as measured by enzyme-linked immunosorbent assay of supernatants generated from popliteal lymph node cells stimulated with leishmanial antigen in vitro. The reduction in parasite numbers induced by IL-12 therapy was still apparent at 10 wk postinfection. In addition, we observed that the administration of a rabbit anti-recombinant murine IL-12 polyclonal antibody (200 micrograms i.p. every other day for 25 d) at the time of infection to resistant C57Bl/6 mice exacerbated disease. These effects were accompanied by a shift in IFN-gamma production in vitro by antigen-stimulated lymph node cells indicative of a Th2-like response. These findings suggest that IL-12 has an important role in initiating a Th1 response and protective immunity.

The effect of tris(hydroxymethyl) aminomethane on membrane bound 5'nucleotidase from swine aortic smooth muscle.

5'-Nucleotidase (5'-ribonucleotide phosphohydrolase, EC 3.1.3.5) activity was stimulated by increasing the concentration of Tris over the range of 1--100 mM. Significant differences were found when the kinetic parameters of the enzyme determined in Tris were compared to those determined in glycine. These data suggest that Tris interacts with 5'-nucleotidase and is therefore unsuitable for use in the assay of the enzyme.

Regulation of the inflammatory response in animal models of multiple sclerosis by interleukin-12.

Interleukin 12 (IL-12), a novel heterodimeric protein produced primarily by antigen-presenting cells, serves as a key regulator of innate and adaptive immune responses. In addition to being a potent inducer of IFN-gamma, IL-12 is widely considered to be the principal cytokine that regulates the generation of Th1 type effector cells. As the successful induction of experimental autoimmune encephalomyelitis (EAE) is associated with a strong Th1 type cellular response, we have evaluated the role of IL-12 in regulating the pathogenesis of EAE in SJL/J mice and Lewis rats. In both settings, treatment with IL-12 was found to accelerate the onset and increase the severity and duration of clinical disease. More importantly, administration of IL-12 to Lewis rats that had recovered from primary disease was found to trigger clinical relapse. In all instances, IL-12-induced exacerbation was associated with a profound increase in iNOS positive macrophages within the perivascular lesions. Although IL-12-induced IFN-gamma does not appear to be required for exacerbation of disease, neutralizing antibodies against murine IL-12 delay the onset and reduce the severity of adoptively transferred EAE, indicating a role for endogenous IL-12 as regulator of disease. Based on the above findings, effective inhibition of IL-12 in vivo may have great therapeutic value in the treatment of MS and other Th1-associated inflammatory disorders.

Constant subcutaneous infusion of rhIL-11 in mice: efficient delivery enhances biological activity.

Previous studies have shown that subcutaneous (SC) bolus administration of recombinant human interleukin-11 (rhIL-11) stimulates megakaryocytopoiesis and increases peripheral platelet counts in naive mice. This study was designed to determine whether administration of rhIL-11 by constant SC infusion altered either the magnitude of the nature of the hematologic response. Female C57BL/6 mice were implanted subcutaneously with 7-day Alzet mini-osmotic pumps containing either rhIL-11 with 0.5% homologous mouse serum (delivery rate of 250 microg/kg/d) or vehicle alone. Mice were sacrificed on days 3, 7, 10, and 13 after pump implantation, and the hematopoietic response was compared to mice receiving an equivalent dose of rhIL-11 administered by SC injection (250 microg/kg/d, 7 days) or vehicle controls. Subcutaneous injection of rhIL-11 resulted in a significant increase in peripheral platelet counts with a maximum platelet increase of 44% over controls observed on day 7 of the study. Platelet counts subsequently declined (24% by day 10) returning to control values by day 13. The increase in peripheral platelet counts was accompanied by an increase in reticulated platelets on day 7 and a shift to higher ploidy bone marrow megakaryocytes on days 3 and 7. Compared to SC injection, both the magnitude and duration of the platelet increase were significantly enhanced following continuous SC infusion of rhIL-11. Maximum platelet counts were detected on day 10 (115% above vehicle controls), and platelets remained significantly elevated on day 13 (84%), 6 days after rhIL-11 administration had stopped. Consistent with the platelet response, the modal ploidy of bone marrow megakaryocytes was shifted from 16N to 32N on days 3 and 7, with increases in 32N megakaryocytes still apparent on days 10 and 13. There was also a significant increase in reticulated platelets detected in the peripheral blood on days 3, 7, and 10 compared to mice administered rhIL-11 by SC injection, The changes in reticulated platelets and bone marrow megakaryocyte ploidy are consistent with the increased and prolonged platelet response following SC infusion of rhIL-11. In addition to the effects observed on peripheral platelet counts, constant SC infusion of rhIL-11 dramatically enhanced splenic hematopoietic activity, increasing spleen weight and cellularity as well as splenic megakaryocyte, erythroid, granulocyte, and macrophage progenitors compared to mice receiving rhIL-11 by SC injection.

Psychopathology in the families of children and adolescents with borderline personality disorder.

OBJECTIVE: The purpose of this study was to determine whether rates of psychopathology differed between the families of a group of children and adolescents with borderline personality disorder and the families of a psychiatric comparison group. METHOD: The rates of psychiatric disorders in the families of 44 child and adolescent outpatients with borderline personality disorder were compared with the rates in the families of a psychiatric comparison group of 100 children and adolescents, none of whom had a diagnosis of borderline personality disorder. Psychopathology in family members was ascertained by the family history method with the use of information from semistructured interviews with the subjects in the two study groups and with their parents or guardians. The adults were systematically interviewed regarding specific DSM-III-R disorders in their families. RESULTS: The families of the patients with borderline personality disorder had significantly greater rates of psychopathology, particularly in the areas of depressive, substance abuse, and antisocial disorders. CONCLUSIONS: The finding of higher rates of psychopathology among the family members of the group with borderline personality disorder supports the hypothesis that a history of significant family psychopathology is associated with the disorder.

Physical and sexual abuse histories among children with borderline personality disorder.

OBJECTIVE: The purpose of the study was to determine whether a history of physical or sexual abuse is more common in children with borderline personality disorder than in other children evaluated in the same outpatient psychiatric clinic. METHOD: The authors contrasted rates of abuse in 44 children diagnosed with borderline personality disorder and in 100 comparison children. RESULTS: The borderline personality disorder group had a significantly greater prevalence of physical and combined physical/sexual abuse. Sexual abuse rates alone did not differ significantly between groups. CONCLUSIONS: The finding of greater abuse in the group with borderline personality disorder supports the hypothesis that a history of trauma is associated with the disorder.

Regulation of experimental autoimmune encephalomyelitis by interleukin-12.

We have evaluated the effects of rmIL-12 on the course of adoptively transferred EAE. When mice were injected with LNC that had been stimulated in vitro with PLP in the presence of rmIL-12, the subsequent course of disease was more severe and prolonged than controls. In vitro stimulation with PLP in the presence of IL-12 was associated with an increase in IFN-gamma and decrease in IL-4-producing cells, indicating a preferential expansion of Th1 effector cells. At peak disease, no notable differences in either the cellular composition or cytokine expression within CNS lesions was seen between groups. However, the frequency of macrophages that stained positively for inducible nitric oxide synthase (iNOS) was increased in animals challenged with rmIL-12 treated LNC. These data suggest that in addition to promoting the preferential expansion of IFN-gamma-producing cells by rmIL-12 treatment in vitro, in vivo effects leading to macrophage activation and iNOS expression may contribute to the severe, protracted course of CNS inflammation in this model. In contrast, treatment of mice with an antibody to murine IL-12 following cell transfer completely prevented paralysis with only 40% of the mice developing mild disease. These data suggest that endogenous IL-12 plays a pivotal role in the pathogenesis of this model of autoimmune disease.

Recruitment and training of child and adolescent psychiatry residents from pediatrics.

This article describes a 21-year experience of recruiting and training child and adolescent psychiatry residents with pediatric backgrounds. Three grounds of physicians are compared: those with previous training in general psychiatry alone, those with previous training in both general psychiatry and pediatrics, and those with previous training in pediatrics alone. Residents with pediatric backgrounds compared favorably with those with general psychiatry training. Those with only pediatric training were not only able to successfully complete the residency, but also the majority entered the field of child psychiatry. The findings support accepting residents directly from pediatrics as a viable pathway into child psychiatry.

An integrated medical and psychiatric approach to conversion symptoms in a four-year-old.

Conversion disorder is a challenging diagnosis in children and adolescents. Medical and psychiatric diagnoses need to be evaluated both separately and in relation to each other. This case highlights both the diagnostic criteria for a conversion disorder in a young child and the need for an integrated medical and psychiatric approach by physicians.

Interleukin-11.

Interleukin-11 (IL-11) is a cytokine which interacts with a variety of haemopoietic and non-haemopoietic cell types. Recombinant human IL-11 (rhIL-11; oprelvekin) is produced in Escherichia coli and differs from the naturally occurring protein only in the absence of the amino-terminal proline residue. In synergy with other factors, rhIL-11 stimulates the growth of myeloid, erythroid, and megakaryocyte progenitor cells in vitro. In vivo, rhIL-11 is active in mice, rats, dogs, guinea pigs, hamsters and non-human primates, where the principal activity measured was stimulation of megakaryocytopoiesis and thrombopoiesis. rhIL-11 has shown benefit in 2 clinical trials by significantly reducing severe chemotherapy-induced thrombocytopenia. In addition to its thrombopoietic activity, rhIL-11 has also shown activity in models of acute gastrointestinal mucosal damage. rhIL-11 enhanced survival in mice following cytoablative therapy and in a hamster model of chemotherapy-induced oral mucositis, where treatment with rhIL-11 was associated with decreased mucosal damage, accelerated healing and reduced numbers of deaths. rhIL-11 is currently in clinical trials for the treatment of chemotherapy-induced mucositis. In rat models of acute colonic injury and inflammatory bowel disease, rhIL-11 treatment reduced intestinal mucosal damage and alleviated clinical signs. rhIL-11 has direct effects on activated macrophages to reduce the production of pro-inflammatory mediators. In animal models of endotoxaemia, rhIL-11 treatment reduced serum levels of pro-inflammatory cytokines and blocked hypotension. rhIL-11 increased survival in models of Gram-negative sepsis and toxic shock. Based on these studies, rhIL-11 is currently in clinical trials for treatment of Crohn's disease. Other inflammatory conditions are being further evaluated. Mechanistically, rhIL-11 functions at many levels to control inflammation, ameliorate tissue damage and maintain haemostasis in the face of trauma or infection. rhIL-11 has direct effects on hepatocytes, inducing the production of acute phase reactant proteins, haem oxygenase and tissue inhibitor of metalloproteinase-1 (TIMP-1). TIMP-1 expression can also be induced in synoviocytes and chondrocytes by treatment with rhIL-11. rhIL-11 administration has been associated with increased plasma levels of von Willebrand factor and fibrinogen. rhIL-11 treatment potentially offers multiple benefits for cancer chemotherapy patients, such as prevention of thrombocytopenia, gastrointestinal epithelial protection and subsequent reduction of mucositis, and amelioration of inflammatory complications. In addition, rhIL-11 is being evaluated further in the treatment of inflammatory disorders such as inflammatory bowel disease, rheumatoid arthritis and sepsis.

Current perspectives on the pharmacotherapy of depressive disorders in children and adolescents.

Major depressive disorder occurs in approximately 2% of prepubertal children and 5% of adolescents. Studies investigating the pharmacotherapy of early-onset major depressive disorder in these young patients have been inconclusive. Early open trials and anecdotal experience suggested a beneficial role for antidepressant therapy. Double-blind placebo-controlled trials have failed to demonstrate the robust response seen in adults, but the studies have been small and concerns have been raised regarding methodology. Nevertheless, the significant morbidity associated with depressive disorders and the positive open trial experiences with antidepressants have led to the recommendation that antidepressants be used early in life when a patient presents with symptoms of a depressive disorder and has significant functional incapacity because of these symptoms. This article will review the studies of antidepressant efficacy in juvenile-onset major depressive disorder and then propose a pharmacotherapy model.

Activation-induced cellular accumulation of histamine in immature but not mature murine mast cells.

Mast cell activation involves the rapid release of inflammatory mediators, including histamine, from intracellular granules. The cells are capable of regranulation and multiple rounds of activation. The goal of this study was to determine if there are changes in the content of pre-formed mast cell mediators after a round of activation. After 24 h, the histamine content of bone marrow-derived mast cells (BMMC), but not that of peritoneal mast cells, exceeded the amount in resting cells. Accumulation of histamine in BMMC peaked at 72 h of activation, and returned toward preactivation levels by 96 h. The increase in histamine content was accompanied by an increase in the gene expression of histidine decarboxylase. No increases in beta hexosaminidase or murine mast cell protease-6 were observed. These findings indicate that BMMC respond to activation by increasing total cell-associated histamine content. This increase may be important to the response of these cells upon subsequent exposure to antigens.

Meeting the information system demands of the future through outsourcing.

As managed care organizations work to meet the rigorous data and information requirements of a rapidly evolving health care system, many are recognizing the need to out-source their computer operations. Developing a cost-effective, efficient approach to outsourcing is a challenge to many organizations. This article offers an in-depth view of outsourcing as it relates to the managed health care industry as well as criteria for selecting an outsourcing consultant or vendor.

Preclinical biology of interleukin 11: a multifunctional hematopoietic cytokine with potent thrombopoietic activity.

Interleukin 11 (IL-11) is a multifunctional hematopoietic cytokine which was originally identified as a factor produced by an IL-1-stimulated primate stromal cell line. The in vitro biological activities of recombinant human (rHu)IL-11 result predominantly from synergistic interactions with other growth factors. In combination with other cytokines, rHuIL-11 has been shown to support the formation of primitive hematopoietic and lymphohematopoietic progenitor colonies from bone marrow, to promote erythroid burst formation and to stimulate both early and late stages of megakaryocyte proliferation and differentiation. rHuIL-11 is biologically active in mice, rats, dogs and primates when administered as a single agent in vivo. The predominant effect of rHuIL-11 in naive mice was on cells of the megakaryocytic lineage, increasing the number of bone marrow megakaryocyte progenitors, stimulating megakaryocyte endoreplication and increasing peripheral platelet counts in a dose-dependent fashion. Similar megakaryocytic stimulatory activity was seen in nonhuman primates treated with rHuIL-11 where platelet counts were increased by as much as 300%. In several models of severe myelosuppression induced by chemotherapy and/or irradiation and in bone marrow transplant models, there were multilineage hematopoietic stimulation following rHuIL-11 treatment. In these models, accelerated recovery of platelets was a consistent observation, while some models show enhanced neutrophil and red blood cell recovery as well. These results from preclinical studies confirm the broad spectrum of biological activities exhibited by rHuIL-11 in vitro, and suggest that this cytokine may be an effective agent in the treatment of myelosuppression and thrombocytopenia associated with cancer chemotherapy and bone marrow transplantation.

Analysis of CD4 and CD2 receptor function.

We have expressed the human CD4 and CD2 molecules in a murine hybridoma, 155.16, that responds to stimulation with human HLA-DR antigens by producing interleukin 2 (IL-2). When stimulated by HLA-DR expressing human cells, the CD4+ and CD2+ hybridomas produce significantly more IL-2 than the parent hybridomas, indicating that CD4 and CD2 are functional. We have used this model system to analyze the role of the CD4 and CD2 surface receptors in T cell activation. Different monoclonal antibodies (mAbs) against CD4 and CD2 were used to define regions of these molecules that may be important for ligand binding and function. Using anti-CD4 mAbs in combination with anti-CD3 mAb, and measuring IL-2 production and mobilization of cellular calcium [( Ca2+]i), we have identified two regions of the CD4 molecule that appear to be important for CD4-dependent functions. Anti-CD4 mAb Leu3a bound in the first immunoglobulin-like domain and appeared to enhance CD4-dependent functions. mAb OKT4F, which bound in or near the second immunoglobulin-like domain, inhibited CD4-dependent functions. The role of CD2 in T cell activation was analyzed by characterizing hybridomas that expressed wild type and mutated CD2 molecules. This analysis has shown that two regions of the external domain of CD2 are involved in binding of lymphocyte-function associated antigen-3 (LFA-3). Furthermore, binding of CD2 to LFA-3 enhanced T cell activation, and this enhancement was dependent on the cytoplasmic domain of the CD2 molecule. These results suggest that the CD2/LFA-3 interaction provides a stimulatory signal for T cell activation.