Towards precision medicine: What are the stratification hypotheses to identify homogeneous inflammatory subgroups.

Diverse lines of research testify a link, presumably causal, between immune dysregulation and the development, course and clinical outcome of psychiatric disorders. However, there is a large heterogeneity among the patients' individual immune profile and this heterogeneity prevents the development of precise diagnostic tools and the identification of therapeutic targets. The aim of this review was to delineate possible subgroups of patients on the basis of clinical dimensions, investigating whether they could lead to particular immune signatures and tailored treatments. We discuss six clinical entry points; genetic liability to immune dysregulation, childhood maltreatment, metabolic syndrome, cognitive dysfunction, negative symptoms and treatment resistance. We describe the associated immune signature and outline the effects of anti-inflammatory drugs so far. Finally, we discuss advantages of this approach, challenges and future research directions.

Collagen-induced arthritis is reduced in 5-lipoxygenase-activating protein-deficient mice.

Collagen-induced arthritis in the DBA/1 mouse is an experimental model of human rheumatoid arthritis. To examine the role of leukotrienes in the pathogenesis of this disease, we have developed embryonic stem (ES) cells from this mouse strain. Here, we report that DBA/1 mice made deficient in 5-lipoxygenase-activating protein (FLAP) by gene targeting in ES cells develop and grow normally. Zymosan-stimulated leukotriene production in the peritoneal cavity of these mice is undetectable, whereas they produce substantial amounts of prostaglandins. The inflammatory response to zymosan is reduced in FLAP-deficient mice. The severity of collagen-induced arthritis in the FLAP-deficient mice was substantially reduced when compared with wild-type or heterozygous animals. This was not due to an immunosuppressive effect, because anti-collagen antibody levels were similar in wild-type and FLAP-deficient mice. These data demonstrate that leukotrienes play an essential role in both the acute and chronic inflammatory response in mice.

Regulation of tumour necrosis factor production by adrenal hormones in vivo: insights into the antiinflammatory activity of rolipram.

1. The role of adrenal hormones in the regulation of the systemic and local production of tumour necrosis factor (TNF alpha) was examined in male Balb/c mice. 2. Intraperitoneal injection of 0.3 mg E. coli lipopolysaccharide (LPS, 0111:B4) led to high levels of circulating TNF alpha without stimulating TNF alpha production in the peritoneal cavity. Systemic production of TNF alpha in response to LPS was increased in adrenalectomized animals and in normal animals treated with the beta-adrenoceptor antagonist, propranolol. The glucocorticoid antagonist, RU 486, did not modify systemic TNF alpha production. These results indicate that systemic TNF alpha production is regulated by adrenaline but not by corticosterone. 3. When mice were primed with thioglycollate, TNF alpha was produced in the peritoneal cavity in response to low dose LPS (1 micrograms). The levels of TNF alpha in the peritoneal cavity were not enhanced by adrenalectomy or by treatment with either propranolol or RU 486, indicating local production of TNF alpha in the peritoneal cavity is not regulated by adrenaline or corticosterone. 4. The phosphodiesterase type IV (PDE-IV) inhibitor, rolipram, inhibited both the systemic production of TNF alpha in response to high dose endotoxin (ED50 = 1.3 mg kg-1) and the local production of TNF alpha in the peritoneal cavity in response to low dose endotoxin (ED50 = 9.1 mg kg-1). In adrenalectomized mice there was a slight reduction in the ability of rolipram to inhibit the systemic production of TNF alpha (ED50 = 3.3 mg kg-1) while the ability of rolipram to inhibit the local production of TNF alpha in the peritoneal cavity was virtually abolished (24% inhibition at 30 mg kg-1). The glucocorticoid antagonist, RU 486, also reduced the ability of rolipram to inhibit local TNF alpha production while propranolol was without effect. 5. Systemic treatment with rolipram increased the plasma concentrations of corticosterone in normal mice but not in adrenalectomized mice indicating that rolipram can cause adrenal stimulation in vivo. 6. In summary, these data indicate that systemic production of TNF alpha in response to high dose endotoxin is controlled differently from the local production of TNF alpha in response to low dose endotoxin. The systemic production of TNF alpha is regulated by catecholamines, but not by corticosterone, while the local production of TNF alpha in the peritoneal cavity is not regulated by basal levels of either catecholamines or corticosterone. 7. These data also show that the ability of rolipram to inhibit the local production of TNF alpha is dependent on the release of corticosterone from the adrenal glands.

Follow-up of leucocyte and reticulocyte counts for the prediction of early graft failure after non-HLA-identical BMT in children.

Allogeneic BMT using a non-genotypically HLA-identical donor may be curative for children suffering from lethal haematological diseases, who lack a genotypically HLA-identical donor. Unfortunately, graft failures are often seen, especially after T cell depletion of the graft. We studied whether untimely decreased counts of leucocytes and reticulocytes in peripheral blood might predict graft failure at an early stage. Fifty-five recipients of a non-genotypically HLA-identical BM graft were included in the study; data from these children were compared with those of 77 recipients of a genotypically HLA-identical BM graft. Time-related reference values of peripheral blood leucocyte and reticulocyte counts were established in graft recipients with proven donor-origin recovery after BMT. Graft failure after nonHLA-identical BMT was observed in 16 out of 55 children (29%) and after HLA-identical BMT in one out of 77 (1.3%). With respect to early graft failure, the predictive value of granulocyte numbers falling below the lower limit of the reference values and a rapid decline of reticulocyte numbers after their appearance in peripheral blood was 100% (95% confidence intervals of 83-100% and of 80-100%, respectively). Early immunosuppressive intervention was applied in six patients and was successful in three of them.

Risk factors for developing EBV-related B cell lymphoproliferative disorders (BLPD) after non-HLA-identical BMT in children.

B cell lymphoproliferative disorders (BLPD) are relatively frequent after genotypically non-HLA-identical BMT. We performed univariate analysis to study which BMT-related variables were associated with an increased risk of developing BLPD. Sixty-five recipients of other than genotypically HLA-identical BM grafts were included in the study. Seventy-seven recipients of genotypically HLA-identical BM grafts served as a comparison group. BLPD occurred in nine of 65 children after non-HLA-identical BMT (14%) and in none of the 77 children after HLA-identical BMT (0%). In all cases, BLPD was proven to be EBV-related. Our data suggest that the combined use of Campath 1G and anti-LFA1 was associated with an increased risk of developing BLPD, particularly children who had received a T cell-depleted BM graft, using albumen density gradient sedimentation followed by E-rosetting, and who were conditioned with Ara-C, CY and TBL. In addition, T cell numbers below 50/microliters at 1 month and below 100/microliters at 2 months after BMT, respectively, were associated with an increased risk of developing BLPD. Longitudinal determination of T cell numbers after non-HLA-identical BMT is a simple method for identifying patients at risk of developing BLPD. In addition to monitoring levels of circulating EBV-infected lymphocytes, monitoring T cell numbers may allow early intervention to prevent progression of BLPD.

Trade-offs in the life history and energy budget of the parthenogenetic collembolan Folsomia candida (Willem).

Three clones of Folsomia candida from different locations in Europe were compared in four experiments investigating genetic and phenotypic correlations between life-history traits. The first three experiments focused on the effects of food type, clone and temperature on traits associated with the first clutch. Differences in clutch size between clones and treatments were almost completely attributable to body size. Clones differed in length of the juvenile period, but the difference decreased at low temperatures. Age and weight at first reproduction were negatively correlated in the food type experiment and positively correlated in the temperature experiment, an often-encountered result for which no general explanation is as yet available. In the temperature experiment egg size variation was considerable, and was highest at low temperatures. The fourth experiment, with two clones at two feeding levels, aimed at finding trade-offs, in particular between reproduction and survival. It was hypothesized that higher fecundity led to increased scenescence through a higher metabolic rate. The trade-off was clearly present among the clones: one combined fast growth, late reproduction and high lifetime fecundity with lower survival, while in the other the relation between these traits was opposite. The proposed mechanism, however, was not confirmed, as no difference in metabolic rate was found. The effect of food level was too small to result in significant differences in the life-history traits in either of the clones.

Interactive effect of reduced pollen availability and Varroa destructor infestation limits growth and protein content of young honey bees.

Varroa destructor in combination with one or more stressors, such as low food availability or chemical exposure, is considered to be one of the main causes for honey bee colony losses. We examined the interactive effect of pollen availability on the protein content and body weight of young bees that emerged with and without V. destructor infestation. With reduced pollen availability, and the coherent reduced nutritional protein, we expected that V. destructor infestation during the pupal stage would have a larger negative effect on bee development than without infestation. Moreover, when raised with ample pollen available after emergence, infested pupae were expected not to be able to compensate for early losses due to V. destructor. We found that both V. destructor infestation and reduced pollen availability reduced body weight, abdominal protein level, and increased the head to abdomen protein ratio. The availability of pollen did indeed not result in compensation for reduced mass and protein content caused by V. destructor infestation in young bees after 1 week of their adult life. Both V. destructor and nutrition are top concerns for those studying honey bee health and this study demonstrates that both have substantial effects on young bees and that ample available pollen cannot compensate for reduced mass and protein content caused by V. destructor parasitism.

A girl with type 1 diabetes and a yellowish appearance.

Type 1 diabetes mellitus in children has been associated with other autoimmune diseases, especially coeliac disease and autoimmune thyroiditis. This association may be the result of a common pathogenic background. We describe the case of a girl with type 1 diabetes mellitus who developed icterus due to autoimmune hepatitis, a disease rarely found in children. Thyroiditis-associated and diabetes-associated autoantibodies were also present. Human leucocyte antigen typing revealed DRB1*03 heterozygosity, which has been associated with the occurrence of both autoimmune hepatitis and type 1 diabetes. This finding implies that similar pathogenic pathways may be involved in different autoimmune diseases including type 1 diabetes and autoimmune hepatitis. The patient was successfully treated with prednisolone and azathioprine. Autoimmune hepatitis can be a serious co-occurring disease in patients with type 1 diabetes.

ATP induces the release of IL-1 from LPS-primed cells in vivo.

The secretion of IL-1 from murine macrophages in vitro is an inefficient process that is distinct from those of other cytokines such as IL-6. We have therefore studied this process in vivo to see if these differences are maintained. Intraperitoneal injection of LPS in mice induced production and release of IL-6 into the extracellular fluid (peritoneal lavage). Although induction of intracellular IL-1 alpha and IL-1 beta was readily detected, these cytokines were not detected extracellularly. Injection of ATP 2 h after LPS led to the rapid extracellular release of IL-1 beta, IL-1 alpha, lactate dehydrogenase, and beta-N-acetylglucosaminidase. Western blot analysis revealed that a large proportion of the IL-1 beta was released as the 17-kDa form, whereas IL-1 alpha was unprocessed. Adenosine 5'-O-(3-thiotriphosphate) was also effective in causing IL-1 release but not UTP or ADP. This suggests that the ATP-mediated release of IL-1 is a receptor-mediated phenomenon that is associated with cell lysis.

GM-CSF rapidly primes mice for enhanced cytokine production in response to LPS and TNF.

Subcutaneous administration of Granulocyte-macrophage-colony stimulating factor (GM-CSF) to mice enhanced LPS-induced cytokine production in the circulation (TNF, IL-6) and peritoneal cavity (IL-1 beta, IL-6). This effect was induced rapidly (within 1 h) and persisted for 4 h. Mice made leukopenic with cyclophosphamide retained the ability to respond to GM-CSF. In addition, TNF induced IL-6 production was also enhanced. These results demonstrate that GM-CSF has a pronounced priming effect on cytokine producing cells in vivo and raises the possibility that this cytokine may contribute to the pathogenesis of septic shock.

Identification and characterization of a novel class of interleukin-1 post-translational processing inhibitors.

Lipopolysaccharide (LPS)-activated monocytes and macrophages produce large quantities of pro-interleukin (IL)-1beta but externalize little mature cytokine. Efficient post-translational processing of the procytokine occurs in vitro when these cells encounter a secretion stimulus such as ATP, cytolytic T cells, or hypotonic stress. Each of these stimuli promotes rapid conversion of 31-kDa pro-IL-1beta to its mature 17-kDa species and release of the 17-kDa cytokine. In this study, two novel pharmacological agents, CP-424,174 and CP-412,245, are identified as potent inhibitors of stimulus-coupled IL-1beta post-translational processing. These agents, both diarylsulfonylureas, block formation of mature IL-1beta without increasing the amount of procytokine that is released extracellularly, and they inhibit independently of the secretion stimulus used. Conditioned medium derived from LPS-activated/ATP-treated human monocytes maintained in the absence and presence of CP-424,174 contained comparable quantities of IL-6, tumor necrosis factor-alpha (TNFalpha), and IL-1RA, but 30-fold less IL-1beta was generated in the test agent's presence. As a result of this decrease, monocyte conditioned medium prepared in the presence of CP-424,174 demonstrated a greatly diminished capacity to promote an IL-1-dependent response (induction of serum amyloid A synthesis by Hep3B cells). Oral administration of CP-424,174 to mice resulted in inhibition of IL-1 in the absence of an effect on IL-6 and TNFalpha. These novel agents, therefore, act as selective cytokine release inhibitors and define a new therapeutic approach for controlling IL-1 production in inflammatory diseases.

Altered cytokine production in mice lacking P2X(7) receptors.

The P2X(7) receptor (P2X(7)R) is an ATP-gated ion channel expressed by monocytes and macrophages. To directly address the role of this receptor in interleukin (IL)-1 beta post-translational processing, we have generated a P2X(7)R-deficient mouse line. P2X(7)R(-/-) macrophages respond to lipopolysaccharide and produce levels of cyclooxygenase-2 and pro-IL-1 beta comparable with those generated by wild-type cells. In response to ATP, however, pro-IL-1 beta produced by the P2X(7)R(-/-) cells is not externalized or activated by caspase-1. Nigericin, an alternate secretion stimulus, promotes release of 17-kDa IL-1 beta from P2X(7)R(-/-) macrophages. In response to in vivo lipopolysaccharide injection, both wild-type and P2X(7)R(-/-) animals display increases in peritoneal lavage IL-6 levels but no detectable IL-1. Subsequent ATP injection to wild-type animals promotes an increase in IL-1, which in turn leads to additional IL-6 production; similar increases did not occur in ATP-treated, LPS-primed P2X(7)R(-/-) animals. Absence of the P2X(7)R thus leads to an inability of peritoneal macrophages to release IL-1 in response to ATP. As a result of the IL-1 deficiency, in vivo cytokine signaling cascades are impaired in P2X(7)R-deficient animals. Together these results demonstrate that P2X(7)R activation can provide a signal that leads to maturation and release of IL-1 beta and initiation of a cytokine cascade.

Design and synthesis of 2-oxo-imidazolidine-4-carboxylic acid hydroxyamides as potent matrix metalloproteinase-13 inhibitors.

A novel series of imidazolidinone-based matrix metalloproteinase (MMP) inhibitors was discovered by structural modification of pyrrolidinone la. Potent inhibition of MMP-13 was exhibited by the analogues having 4-(4-fluorophenoxy)phenyl (4a, IC50 = 3 nM) and 4-(naphth-2-yloxy)phenyl (4h, IC50 = 4 nM) as P1' groups.

Endocrinologic disorders and optic pathway gliomas in children with neurofibromatosis type 1.

OBJECTIVE: To establish the prevalence of endocrinologic disorders in children with neurofibromatosis type 1 (NF1) and the relationship between these disorders and cerebral abnormalities on magnetic resonance imaging. DESIGN: A prospective follow-up study. Setting. A multidisciplinary neurofibromatosis clinic. PATIENTS: A total of 122 children diagnosed with NF1 according to diagnostic criteria set by the National Institutes of Health. RESULTS: Central precocious puberty (CPP) was diagnosed in 3 children and growth hormone deficiency (GHD) in 3 children. Optic pathway gliomas were observed in 15 children; in 9 of the 15 cases, the optic chiasm was involved. Of the 3 children with CPP, only 1 showed a chiasma glioma on magnetic resonance imaging. In 1 case with GHD, an optic chiasm glioma was detected on neuroimaging. Two of the 9 children with an optic chiasm glioma presented with CPP or GHD. CONCLUSIONS: It has been suggested that CPP in children with NF1 is found exclusively in the presence of a chiasma glioma. We conclude that chiasma glioma may not be obligatory in children with NF1 and CPP or GHD. Moreover, we report a prevalence of GHD in children with NF1 of 2.5%, which has not been established earlier.

The preclinical pharmacological profile of the potent and selective leukotriene B4 antagonist CP-195543.

CP-195543 [(+)-2-(3-benzyl-4-hydroxy-chroman-7-yl)-4-trifluoromethyl-benzoic acid] is a structurally novel, selective and potent leukotriene B4 (LTB4) receptor antagonist. In vitro CP-195543 inhibited [3H]LTB4 binding to high-affinity LTB4 receptors on human neutrophils (HN) and murine spleen membranes with IC50 values of 6.8 nM (Ki = 4.9 nM) and 37.0 nM (Ki = 26.9 nM), respectively. CP-195543 inhibited human and mouse neutrophil chemotaxis mediated by LTB4 with IC50 values of 2.4 nM and 7.5 nM, respectively. Evidence of noncompetitive antagonist effects on the HN high-affinity LTB4 receptor was obtained by Scatchard analysis of [3H]LTB4 binding to and chemotaxis of HN to LTB4. Scatchard analyses of [3H]LTB4 binding to low-affinity receptors on HN indicated that CP-195543 acted as a competitive antagonist at this receptor, and inhibition of LTB4-mediated CD11b up-regulation on HN was inhibited competitively by CP-195543 (pA2 = 7.66). In whole blood, CP-195543 also blocked CD11b up-regulation on HN (pA2 = 7.12) and murine neutrophils (pA2 = 7.06) with a similar potency. LTB4-mediated CD11b up-regulation on human monocytes and eosinophils in whole blood were inhibited by CP-195543 with IC50 values of 270 nM and 420 nM, respectively. CP-195543 at 10 microM failed to inhibit HN chemotaxis and CD11b up-regulation mediated through alternative (i.e., complement fragment 5a, interleukin-8, platelet-activating factor) G-protein-coupled chemotactic factor receptors. In vivo, after oral administration, CP-195543 blocked LTB4-mediated neutrophil infiltration in guinea pig and murine skin with ED50 values of 0.1 mg/kg and 2.8 mg/kg p.o., respectively. When administered in osmotic pumps, CP-195543 reduced the clinical symptoms and attendant weight loss in an IL-1-exacerbated murine model of collagen-induced arthritis with half-maximal effects associated with plasma drug levels of 0.4 to 0.5 microg/ml. Collectively these data provide evidence of the in vitro potency and in vivo efficacy of a novel LTB4 antagonist and support its clinical evaluation in a variety of inflammatory diseases in man.