Prospective association between tobacco smoking and death by suicide: a competing risks hazard analysis in a large twin cohort with 35-year follow-up.

BACKGROUND: The relationship between smoking and suicide remains controversial. METHOD: A total of 16 282 twin pairs born before 1958 in Finland and alive in 1974 were queried with detailed health and smoking questionnaires in 1975 and 1981, with response rates of 89% and 84%. Smoking status and dose, marital, employment, and socio-economic status, and indicators of psychiatric and somatic illness were assessed at both time points. Emergent psychiatric and medical illness and vital status, including suicide determined by forensic autopsy, were evaluated over 35-year follow-up through government registries. The association between smoking and suicide was determined in competing risks hazard models. In twin pairs discordant for smoking and suicide, the prospective association between smoking and suicide was determined using a matched case-control design. RESULTS: Smokers had a higher cumulative suicide incidence than former or never smokers. Heavy smokers had significantly higher suicide risk [hazard ratio (HR) 3.47, 95% confidence interval (CI) 2.31-5.22] than light smokers (HR 2.30, 95% CI 1.61-3.23) (p = 0.017). Compared with never smokers, smokers, but not former smokers, had increased suicide risk (HR 2.56, 95% CI 1.43-4.59), adjusting for depressive symptoms, alcohol and sedative-hypnotic use, and excluding those who developed serious somatic or psychiatric illness. In twin pairs discordant for smoking and suicide, suicide was more likely in smokers [odds ratio (OR) 6.0, 95% CI 2.06-23.8]. CONCLUSIONS: Adults who smoked tobacco were more likely to die by suicide, with a large, dose-dependent effect. This effect remained after consideration of many known predictors of suicide and shared familial effects, consistent with the hypothesis that exposure to tobacco smoke increases the risk of suicide.

Development of composite outcomes for individual patient data (IPD) meta-analysis on the effects of diet and lifestyle in pregnancy: a Delphi survey.

OBJECTIVE: To develop maternal, fetal, and neonatal composite outcomes relevant to the evaluation of diet and lifestyle interventions in pregnancy by individual patient data (IPD) meta-analysis. DESIGN: Delphi survey. SETTING: The International Weight Management in Pregnancy (i-WIP) collaborative network. Sample Twenty-six researchers from the i-WIP collaborative network from 11 countries. METHODS: A two-generational Delphi survey involving members of the i-WIP collaborative network (26 members in 11 countries) was undertaken to prioritise the individual outcomes for their importance in clinical care. The final components of the composite outcomes were identified using pre-specified criteria. MAIN OUTCOME MEASURES: Composite outcomes considered to be important for the evaluation of the effect of diet and lifestyle in pregnancy. RESULTS: Of the 36 maternal outcomes, nine were prioritised and the following were included in the final composite: pre-eclampsia or pregnancy-induced hypertension, gestational diabetes mellitus (GDM), elective or emergency caesarean section, and preterm delivery. Of the 27 fetal and neonatal outcomes, nine were further evaluated, with the final composite consisting of intrauterine death, small for gestational age, large for gestational age, and admission to a neonatal intensive care unit (NICU). CONCLUSIONS: Our work has identified the components of maternal, fetal, and neonatal composite outcomes required for the assessment of diet and lifestyle interventions in pregnancy by IPD meta-analysis.

Human memory CD4+ T cell response to the major dog allergen Can f 5, prostatic kallikrein.

BACKGROUND: Human CD4+ T cell responses to important animal allergens are still insufficiently understood. OBJECTIVE: To comprehensively characterize in vitro and ex vivo the peripheral blood memory CD4+ T cell responses of subjects with and without allergy to the major dog allergen Can f 5, the only known animal allergen in the kallikrein family of proteins. METHODS: Can f 5-specific memory CD4+ T cell lines (TCLs) were established from the peripheral blood of 12 subjects with and 12 subjects without allergy to Can f 5 and characterized for their functional and phenotypic properties. The results were evaluated with those obtained ex vivo with a novel CD154 enrichment method. The epitopes recognized by the Can f 5-specific TCLs were determined with 72 overlapping 16-mer peptides covering the sequence of the allergen. RESULTS: Can f 5-specific TCLs were obtained at about tenfold higher frequency from allergic than from non-allergic subjects. Functionally, the TCLs of allergic subjects displayed a Th2-biased cytokine phenotype and increased T cell receptor avidity, whereas the TCLs of non-allergic subjects displayed a Th1-/Th0-biased cytokine phenotype and lower TCR avidity. The higher frequency and the Th2 phenotype of Can f 5-specific memory CD4+ T cells in allergic subjects were confirmed by the CD154 enrichment method ex vivo. Six distinct T cell epitope regions of Can f 5 were predominantly recognized by the TCLs from allergic subjects. CONCLUSIONS AND CLINICAL RELEVANCE: Can f 5-specific memory CD4+ T cell responses differ considerably between subjects with and without allergy, as assessed by both in vitro and ex vivo approaches. Peptides containing the dominant T cell epitopes of Can f 5 can be employed for developing peptide-based immunotherapy for dog allergy.

Co-morbidities in Finnish patients with rheumatoid arthritis: 15-year follow-up.

OBJECTIVES: To study the prevalence and importance of co-morbidities in patients with rheumatoid arthritis (RA) at the time of the diagnosis and after a 15-year follow-up, focusing on the relationship between co-morbidity and disease activity. METHOD: The study population comprised 87 patients with early RA (mean age 44 years, 79% female, and 65% rheumatoid factor positive) collected from the Helsinki area between 1986 and 1989. Data for co-morbidities were collected at baseline and at a 15-year examination or at the time of death, and the age-weighted Charlson co-morbidity index (CCIa) at baseline was calculated for each patient. The disease activity score based on 28 joints (DAS28) was assessed with three parameters at baseline and during the first year (DAS28 AUC0-12). The relationship between co-morbidity and activity of RA was studied in groups CCIa 0, CCIa 1-2, and CCIa ≥ 3. RESULTS: Adequate data were available in 80 patients with a mean age of 60 years and a mean disease duration of 15.4 years. At baseline, 20% of patients had at least one co-morbid condition (CC). At endpoint, 60% of the patients had some co-morbidity: 34% had one CC, 19% two, 5% three, and 2% four CCs. The most common end-point CCs were hypertension (30%), cardiovascular diseases (14%), and malignancies (11%). DAS28 AUC0-12 and DAS28 at end-point were higher in groups CCIa1-2 and CCIa ≥ 3 than in CCIa 0. CONCLUSIONS: Co-morbidities increased during the 15 years of RA and the patients with high baseline CCIa showed higher disease activity both in early disease and at end-point.

Mammal-derived respiratory lipocalin allergens do not exhibit dendritic cell-activating capacity.

Most mammal-derived respiratory allergens belong to the lipocalin family of proteins. Determinants of their allergenic capacity are still unknown. Innate immune cells, in particular dendritic cells, have been shown to be involved in the allergenicity of some proteins. As recognition by dendritic cells is one of the few plausible mechanisms for the allergenicity of proteins, we wanted to investigate their role in the allergenicity of lipocalin allergens. Therefore, we first incubated human monocyte-derived dendritic cells with immunologically functional recombinant allergens mouse Mus m 1, dog Can f 1 and 2, cow Bos d 2, horse Equ c 1 and natural Bos d 2. Then, the surface marker expression and cytokine production of dendritic cells and their capacity to promote T cell proliferation and Th2 immune deviation in naïve CD4(+) T cells were examined in vitro. We found that near to endotoxin-free lipocalin allergens had no effect on the activation, allostimulatory capacity or cytokine production of dendritic cells. The dendritic cells could not induce immune deviation in naïve CD4(+) T cells. In contrast, lipopolysaccharide activated the dendritic cells efficiently. However, lipocalin allergens were not able to modify the lipopolysaccharide-induced responses. We conclude that an important group of mammal-derived respiratory allergens, lipocalins, appear not to be able to activate dendritic cells, a major component involved in the allergenicity of some proteins. It is conceivable that this incapacity of lipocalin allergens to arouse innate immunity may be associated with their poor capacity to induce a strong T cell response, verified in several studies.

Preventing excessive gestational weight gain--a secondary analysis of a cluster-randomised controlled trial.

BACKGROUND: Healthy diet, physical activity and modest weight gain during pregnancy may prevent developing gestational diabetes mellitus (GDM). We examined whether a lifestyle intervention designed to prevent GDM was effective in reducing excessive gestational weight gain (GWG). METHODS: A cluster-randomised controlled trial (n=399) was conducted in maternity clinics in 14 municipalities in Southern Finland. Pregnant women with at least one risk factor for GDM (for example, overweight) but no pre-existing diabetes were recruited at 8-12 weeks' gestation. The intervention included counselling on GWG, physical activity and healthy eating at five routine visits. Usual counselling practices were continued in the usual care municipalities. Statistical analyses were performed using multilevel linear and logistic regression models adjusted for weeks' gestation at last weight measurement, pre-pregnancy body mass index and smoking status. RESULTS: The intervention group had a lower mean GWG by weeks' gestation than the usual care group (adjusted coefficient for the between-group difference -0.016 kg per day, P=0.041). There was no difference in mean (± s.d.) GWG between the intervention and the usual care groups (13.7 ± 5.8 vs 14.3 ± 5.0 kg, P=0.64). In total, 46.8% of the intervention group and 54.4% of the usual care group exceeded the GWG recommendations. The adjusted odds ratio for excessive GWG was 0.82 (95% CI 0.53-1.26, P=0.36) in the intervention group as compared with the usual care group. CONCLUSIONS: The intervention had minor effects on GWG among women who were at increased risk for GDM. In order to prevent excessive GWG, additional focus on restriction of energy intake may be needed.

Increased peripheral blood CD4+ T cell responses to deamidated but not to native gliadin in children with coeliac disease.

T cell recognition of gliadin from dietary gluten is essential for the pathogenesis of coeliac disease (CD). The aim of the present study was to analyse whether gliadin-specific T cells are detectable in the circulation of children with newly diagnosed coeliac disease by using a sensitive carboxfluorescein diacetate succinimidyl ester (CFSE) dilution method. Peripheral blood CD4(+) T cell responses were analysed in 20 children at diagnosis of CD and compared to those in 64 healthy control children carrying the CD-associated human leucocyte antigen (HLA)-DQ2 or -DQ8 alleles. Deamidated gliadin (gTG)-specific T cells were detectable in the peripheral blood of more than half the children with CD (11 of 20, 55%) compared to 15 of 64 (23.4%) of the control children (P = 0.008). Proliferative responses to gTG were also significantly stronger in children with CD than in controls (P = 0.01). In contrast, T cells specific to native gliadin were detectable at comparable frequencies in children with CD (two of 19, 10.5%) and controls (13 of 64, 20.3%). gTG-specific T cells had a memory phenotype more often than those specific to native gliadin in children with CD (P = 0.02), whereas controls had similar percentages of memory cells in both stimulations. Finally, gTG-specific CD4(+) T cells had a higher expression of the gut-homing molecule ß7 integrin than those specific to the control antigen tetanus toxoid. Collectively, our current results demonstrate that the frequency of circulating memory CD4(+) T cells specific to gTG but not native gliadin is increased in children with newly diagnosed CD.

Mammalian lipocalin allergens--insights into their enigmatic allergenicity.

Most of the important mammal-derived respiratory allergens, as well as a milk allergen and a few insect allergens, belong to the lipocalin protein family. As mammalian lipocalin allergens are found in dander, saliva and urine, they disperse effectively and are widely present in the indoor environments. Initially, lipocalins were characterized as transport proteins for small, principally hydrophobic molecules, but now they are known to be involved in many other biological functions. Although the amino acid identity between lipocalins is generally at the level of 20-30%, it can be considerably higher. Lipocalin allergens do not exhibit any known physicochemical, functional or structural property that would account for their allergenicity, that is, the capacity to induce T-helper type 2 immunity against them. A distinctive feature of mammalian lipocalin allergens is their poor capacity to stimulate the cellular arm of the human or murine immune system. Nevertheless, they induce IgE production in a large proportion of atopic individuals exposed to the allergen source. The poor capacity of mammalian lipocalin allergens to stimulate the cellular immune system does not appear to result from the function of regulatory T cells. Instead, the T cell epitopes of mammalian lipocalin allergens are few and those examined have proved to be suboptimal. Moreover, the frequency of mammalian lipocalin allergen-specific CD4(+) T cells is very low in the peripheral blood. Importantly, recent research suggests that the lipocalin allergen-specific T cell repertoires differ considerably between allergic and healthy subjects. These observations are compatible with our hypothesis that the way CD4(+) T-helper cells recognize the epitopes of mammalian lipocalin allergens may be implicated in their allergenicity. Indeed, as several lipocalins exhibit homologies of 40-60% over species, mammalian lipocalin allergens may be immunologically at the borderline of self and non-self, which would not allow a strong anti-allergenic immune response against them.

Impact of early radiographic remission on the 15-year radiographic outcome in patients with rheumatoid arthritis.

OBJECTIVE: To investigate the 15-year radiographic outcome in patients with rheumatoid arthritis (RA) in relation to early radiographic remission. METHODS: A cohort of 87 patients with RA, treated with early-initiated disease-modifying anti-rheumatic drug (DMARD) therapy, was followed up prospectively for 15 years. Radiographs of hands and feet were taken at baseline and at 1, 2, 3, 5, 7, 10, and 15 years, and radiographs of large joints at 15 years. Radiographic outcome was assessed by the Larsen score (LS). Early radiographic remission was defined as a change of ≤ 1 Larsen unit in a year, during the first 2 years. RESULTS: A complete set of radiographs for evaluation was available from 69 patients. Outcome was evaluated in three groups: group A comprised 18 (26%) patients with sustained early radiographic remission (at both year 1 and year 2); group B comprised 20 (29%) patients with temporary early radiographic remission (at either year 1 or year 2); and group C comprised 31 (45%) patients with no early radiographic remission. Radiographic outcome was most favourable in patients with sustained early radiographic remission. The mean change in LS over 15 years was 11 [95% confidence interval (CI) 0-22] in group A, 30 (95% CI 12-51) in group B, and 62 (95% CI 45-81) in group C (p < 0.001). A similar relationship to large joint damage (Larsen large joint score) was seen. CONCLUSIONS: Compared with patients with progressive erosions, our results indicate that early radiographic remission relates to a better long-term radiographic outcome in RA regarding both small joint and large joint changes.

Can disease-modifying anti-rheumatic drugs be discontinued in long-standing rheumatoid arthritis? A 15-year follow-up.

OBJECTIVE: To investigate the 15-year outcome of patients with early rheumatoid arthritis (ERA) with respect to the continuity of treatment. METHODS: We conducted a 15-year follow-up study of 87 patients with ERA treated since diagnosis with disease-modifying anti-rheumatic drugs (DMARDs) according to the 'sawtooth' strategy. The patients were divided into groups according to the continuity of treatment: (A) 'continuous DMARDs', (B) 'discontinued and restarted DMARDs', and (C) 'permanently discontinued DMARDs'. The main outcome measurements included the Health Assessment Questionnaire (HAQ), the Larsen score, and clinical remission according to the American Rheumatism Association (ARA) criteria. RESULTS: Seventy (80%) patients participated in the 15-year follow-up. DMARDs were discontinued in 20 (29%) patients due either to remission or to a symptom-free period of the disease. The disease flared up in nine (45%) of these patients, in some patients several years after the discontinuation. At the 15-year follow-up, 59 (84%) patients were on DMARDs; only three (4%) were using biologicals. Functional capacity remained good in all groups (mean HAQ score 0.52). The mean Larsen score was higher (54) in group A than in groups B (25) and C (12) (p =0.001). The remission rate was 64% in group C and considerably lower in groups A (6%) and B (0%) (p<0.001). CONCLUSIONS: Our results indicate that most of the patients with long-standing RA require continuous DMARD treatment. If the treatment is discontinued, patients should be followed-up closely and DMARDs readministered without delay if the disease flares up.

Animal-derived lipocalin allergens exhibit immunoglobulin E cross-reactivity.

BACKGROUND: Although knowledge of the IgE cross-reactivity between allergens is important for understanding the mechanisms of allergy, the regulation of the allergic immune response and the development of efficient modes of allergen immunotherapy, the cross-reactivity of animal allergens is poorly known. OBJECTIVE: The aim of this study was to characterize IgE cross-reactivities between lipocalin proteins, including five animal-derived lipocalin allergens and one human endogenous lipocalin, tear lipocalin (TL). METHODS: The recombinant proteins were validated by chromatography and mass spectrometry. The IgE-binding capacity of the allergens was confirmed by IgE. immunoblotting and IgE immunoblot inhibition. IgE ELISA was performed with sera from 42 atopic patients and 21 control subjects. The IgE cross-reactivities between the lipocalin proteins were determined by ELISA inhibition. RESULTS: ELISA inhibition revealed IgE cross-reactivities between Can f 1 and human TL, between Can f 1 and Can f 2, and between Equ c 1 and Mus m 1. Low levels of IgE to human TL were found in the sera of seven dog-allergic patients of whom six were IgE-positive for Can f 1. CONCLUSION: Several lipocalins exhibited IgE cross-reactivity, probably due to the sequential identity of the proteins and also due to similarities in their three-dimensional structures. The clinical significance of the findings needs to be elucidated. Low-level IgE cross-reactivity can play a role in regulating immune response to lipocalin allergens.

Features of hospitalisations for acute exacerbation of COPD resulting in death.

BACKGROUND: Hospitalisation periods for the acute exacerbation phase of COPD are a strain on health facilities and entail high rates of hospital mortality. The aim of this study was to ascertain the characteristics of treatment periods resulting in death and the risk factors involved on the basis of treatment registers and death certificates. METHODS: Data on all treatment periods for persons over 44 years of age with a principal diagnosis of COPD that began as emergency admissions applying to the period 1993-2001 was gathered from the hospital treatment register maintained by the Finnish National Research and Development Centre for Welfare and Health, yielding a total of 72 896 cases. Data on the deaths of the patients concerned was then obtained from Statistics Finland and those treatment periods which could be shown to have ended in death (N = 2331) were taken to form the material for analysis. These were compared with a same number of control hospitalisation periods (not ending in death) in terms of specialisation, type and geographical location of the hospital, length of the treatment period and the occurrence of subsidiary diagnoses. Attention was also paid to the season of the year and the days of the week on which admission and death took place. RESULTS: The proportion of emergency admissions that ended in death was 3.2%, The patients concerned having a mean age of 74.5 years for men and 75.0 years for women on admission. The mean duration of the treatment period was 11.5 days (SD 14.8), compared with 8.0 days (SD 7.9) for the controls. A subsidiary diagnosis existed in the case of 53.6% of the periods ending in death and 37.5% of the control periods. Deaths were most frequent on Fridays, 15.6%, and least so on Tuesdays, 13.0%. Where 24.2% of patients admitted on Saturdays or Sundays died during the first 24 hours, the figure for those admitted on weekdays was only 17.7%. Altogether 62.8% of the treatment periods ending in death took place between December and May. CONCLUSIONS: The COPD patients admitted at weekends showed the poorest survival, while concurrent diseases and protraction of the treatment period in winter and early spring increased the risk of death. Recognition of risk cases on admission could enable mortality to be reduced and allow savings in terms of costs through the intensification of treatment in these cases.

The major horse allergen Equ c 1 contains one immunodominant region of T cell epitopes.

BACKGROUND: Despite the fact that most significant mammalian respiratory allergens are lipocalin proteins, information on the human T cell reactivity to these allergenic proteins is largely missing. OBJECTIVE: Knowing the T cell epitopes in allergens is a prerequisite for developing novel preparations for allergen immunotherapy. METHODS: Specific T cell lines were generated with recombinant Equ c 1 from the peripheral blood mononuclear cells (PBMCs) of 10 horse-allergic subjects. For determining T cell epitopes, the lines were stimulated with 16mer synthetic Equ c 1 peptides overlapping by 14 amino acids. The binding capacity of Equ c 1 peptides to human leucocyte antigen class II molecules was determined by the competitive ELISA. RESULTS: The major horse allergen Equ c 1 resembles two other lipocalin allergens, the major cow allergen Bos d 2 and the major dog allergen Can f 1, in that it is weakly stimulatory for the PBMCs of sensitized subjects. Moreover, the T cell epitopes of Equ c 1 are clustered in a few regions along the molecule, as is the case with Bos d 2 and Can f 1. Similar to Bos d 2, Equ c 1 contains one immunodominant epitope region at the carboxy-terminal end of the molecule. The T cell lines of eight horse-allergic subjects out of 10 showed strong reactivity to one or both of the two overlapping peptides, p143-158 and p145-160, in this region. The region probably contains two overlapping epitopes. CONCLUSION: The 18mer peptide p143-160 from the immunodominant region of Equ c 1 is a potential candidate for the peptide-based immunotherapy of horse-sensitized subjects.

Preventing excessive weight gain during pregnancy - a controlled trial in primary health care.

OBJECTIVE: To investigate whether individual counselling on diet and physical activity during pregnancy can have positive effects on diet and leisure time physical activity (LTPA) and prevent excessive gestational weight gain. DESIGN: A controlled trial. SETTING: Six maternity clinics in primary health care in Finland. The clinics were selected into three intervention and three control clinics. SUBJECTS: Of the 132 pregnant primiparas, recruited by 15 public health nurses (PHN), 105 completed the study. INTERVENTIONS: The intervention included individual counselling on diet and LTPA during five routine visits to a PHN until 37 weeks' gestation; the controls received the standard maternity care. RESULTS: The counselling did not affect the proportion of primiparas exceeding the weight gain recommendations or total LTPA when adjusted for confounders. The adjusted proportion of high-fibre bread of the total weekly amount of bread decreased more in the control group than in the intervention group (difference 11.8%-units, 95% confidence interval (CI) 0.6-23.1, P=0.04). The adjusted intake of vegetables, fruit and berries increased by 0.8 portions/day (95% CI 0.3-1.4, P=0.004) and dietary fibre by 3.6 g/day (95% CI 1.0-6.1, P=0.007) more in the intervention group than in the control group. There were no high birth weight babies (>or=4000 g) in the intervention group, but eight (15%) of them in the control group (P=0.006). CONCLUSIONS: The counselling helped pregnant women to maintain the proportion of high-fibre bread and to increase vegetable, fruit and fibre intakes, but was unable to prevent excessive gestational weight gain.

Classic disease modifying anti-rheumatic drugs (DMARDs) in combination with infliximab. The Finnish experience.

To assess the performance of infliximab in a clinical setting, 364 rheumatoid arthritis (RA) patients from the National Register of Biological Treatment in Finland (ROB-FIN) were analysed. Corticosteroid usage and dose diminished (p<0.05 and 0.001, respectively) in patients on infliximab, of whom 51% also used one, 28% two and 16% three other concomitant DMARDs. A 34% of the RA patients used methotrexate+/-corticosteroids without any other DMARD. Methotrexate was most frequently used with sulphasalazine and/or hydroxychloroquine. Non-methotrexate patients most frequently used leflunomide or azathioprine combined with corticosteroids. The clinical effect of these combinations was similar to that of infliximab with methotrexate alone. The results indicate that infliximab can be used together with other DMARDs than methotrexate alone, quite according to the philosophy of the combination drug therapy, as the effectiveness is as good as or even slightly better than that of methotrexate and infliximab.

The DR4-DQ8 haplotype and a specific T cell receptor Vbeta T cell subset are associated with absence of allergy to Can f 1.

BACKGROUND: The significance of specific T cell receptor (TCR) Vbeta subtypes and human leucocyte antigen (HLA) class II alleles for the development of allergy to lipocalin allergens such as the major dog allergen Can f 1 is not clear at present. OBJECTIVE: To characterize the TCR Vbeta usage in the Can f 1-specific T cell lines and the HLA class II genotypes of Can f 1-allergic and non-allergic subjects. METHODS: T cell lines were induced with recombinant Can f 1 from the peripheral blood mononuclear cells of 12 non-atopic dog owners and 26 dog-allergic patients. Thirteen of the dog-allergic subjects were sensitized to Can f 1. Expression of the TCR Vbeta subtypes on CD4(+) T cells in the T cell lines was measured by flow cytometry. The subjects were HLA genotyped for DRB1, DQB1 and DPB1 loci. RESULTS: Can f 1-specific T cell lines were obtained from 18 subjects, with either positive (n=8) or negative (n=10) skin prick tests (SPTs) to recombinant Can f 1. The frequency of TCR Vbeta5.1(+) T cells was significantly higher in the T cell lines of subjects with negative SPTs to the allergen. Moreover, DR4-DQ8 haplotype was over-represented among these subjects. CONCLUSION: The DR4-DQ8 haplotype and the TCR Vbeta5.1(+) CD4(+) T cells may be protective against allergy to Can f 1.

Assessment of recombinant dog allergens Can f 1 and Can f 2 for the diagnosis of dog allergy.

BACKGROUND: The use of recombinant allergens for the diagnosis and immunotherapy of allergy may offer several advantages over allergen extracts. OBJECTIVE: To produce recombinant dog allergens Can f 1 and Can f 2 in Pichia pastoris yeast and to assess their suitability for the diagnosis of dog allergy. METHODS: Clinically diagnosed dog-allergic patients' and healthy non-atopic dog owners' reactivities against recombinant Can f 1 and Can f 2 and commercial dog epithelial extract were studied by a panel of methods including skin prick test (SPT), ELISA and IgE immunoblotting. RESULTS: Recombinant Can f 1 and Can f 2 were found immunologically functional: they bound dog-allergic patients' IgE in immunoblotting and inhibited specifically the binding of IgE to their natural counterparts in the dog allergen extract. Moreover, patients' IgE reactivity in immunoblotting to natural Can f 1 and their SPT with the recombinant allergen were perfectly concordant (phi coefficient 1.0, P<0.001). The concordance was slightly lower with recombinant Can f 2 (phi coefficient 0.92, P<0.001). A lower number of dog-allergic patients, 52%, reacted against Can f 1 than previously reported. About one-third of the patients reacted to Can f 2. In immunoblotting, the highest prevalence of reactivity, 60%, was directed to an 18 kDa component. Aminoterminal sequencing showed this to be a previously unidentified allergenic protein. CONCLUSIONS: The recombinant allergens can be used reliably to identify Can f 1 and Can f 2-sensitized individuals. However, the two allergens are insufficient as reagents for diagnosing dog allergy.

Pregnancy weight gain from 1960s to 2000 in Finland.

OBJECTIVE: To study secular trends in average pregnancy weight gain between the 1960s and 2000 in Finland, and whether the changes were related to body mass index (BMI), age or parity. DESIGN: Three cross-sectional population surveys in Finland from three different periods. SUBJECTS: Women who were pregnant in Helsinki in the period 1954-1963 (N=2262), or in Tampere in the period 1985-1986 (N=1771) or in 2000-2001 (N=371). MEASUREMENTS: Pregnancy weight gain was determined from self-reported prepregnancy weight and measured weights during pregnancy. RESULTS: The mean age and prepregnancy BMI of all pregnant women increased between the 1960s and 2000 (from 26.5 to 29.6 y, from 21.9 to 23.7 kg/m(2)). The mean pregnancy weight gain, adjusted for mother's age, BMI and parity, increased from the 1960s to the mid-1980s from 13.2 to 14.3 kg. The increase was observed in all BMI categories. Compared to the 1960 cohort, the proportion of women with a pregnancy weight gain of less than 10 kg decreased and the proportion of women with a weight gain of 15 kg or more increased in the 1980 cohort. After the mid-1980s, the average pregnancy weight gain remained the same. In all cohorts, overweight women gained least weight during pregnancy, but age and parity were not associated with BMI and parity-/age-adjusted pregnancy weight gain. Higher pregnancy weight gain was associated with higher mean child's birthweight and higher proportion of high birthweight babies in all cohorts. CONCLUSIONS: The mean pregnancy weight gain has increased since the 1960s, which may be of importance with regard to the development of later obesity. Factors other than changes in prepregnancy BMI, age and parity must explain the increased pregnancy weight gain over time.

Probing the mechanisms of low immunogenicity of a lipocalin allergen, Bos d 2, in a mouse model.

BACKGROUND: Bos d 2, a major bovine allergen of the lipocalin family, stimulates very weakly cow dust-asthmatic subjects' peripheral blood mononuclear cells and the spleen cells of several inbred mouse strains immunized with the allergen. OBJECTIVE: To identify the immune mechanisms accounting for the weak stimulatory capacity of Bos d 2. METHODS: The spleen cell responses of BALB/c mice immunized with the allergen and with hen egg lysozyme and tetanus toxoid as control antigens were examined using several in vitro methods. RESULTS: Analysis of the numbers of spleen cells in the antigen-stimulated in vitro cultures with the vital dye 7-amino-actinomycin D showed that Bos d 2 induced a smaller expansion of cells in comparison with the control antigens. Increased cell death in vitro did not account for the weak response against Bos d 2. The number of spleen cells reacting against Bos d 2 also proved to be the lowest when they were analysed by labelling the stimulated cells with 5-6-carboxyfluorescein diacetate succinimidyl ester or by enumerating cytokine-secreting cells by ELISPOT. Eliminating CD8+ cells in the in vitro culture did not enhance the response against Bos d 2. Bos d 2 was also the weakest of the antigens to stimulate the production of soluble cytokines. Adding IL-2, IL-4 or antibody against TGF-beta in the antigen-stimulated spleen cell cultures enhanced the proliferative responses against all the antigens, whereas adding IL-12 or antibody against IL-4 or IL-10 did not enhance the responses. CONCLUSION: The results exclude several mechanisms of peripheral tolerance as an explanation for the poor immune response against Bos d 2, and suggest that the allergen is recognized by a low number of specific T cells. The weak immunogenicity of Bos d 2 may be related to its allergenicity.

Heparan sulphate sulphotransferase expression in mice and Caenorhabditis elegans.

Heparan sulphate (HS) acts as a multifunctional cell regulator, with specific sulphated saccharide sequences designed for selective interactions with many proteins. Functionally, these interactions result in regulation of the protein activities, and there is growing evidence that cells can dynamically alter the structure of HS sequences that they display. HS biosynthesis involves the action of a complex set of enzymes with polymerase, epimerase and sulphotransferase (ST) activities. In higher organisms, multiple isoforms of STs decorate the nascent HS chains with specific patterns of sulphation that confer selective biological functions. The study of HSSTs in model organisms provides a valuable opportunity to examine the expression of these enzymes in relation to the structure and activities of the HS produced. Here we describe that, in mice, there are stage-specific combinations of HSST isoenzymes that underlie the synthesis of different HS species at different times in the developing brain. This differential expression of HSSTs results in the synthesis of structurally variant HS species that form functional signalling complexes with specific fibroblast growth factors and their receptors. Regulated synthesis of specific HS species could be a mechanism for the regulation of proliferation and differentiation in the developing brain. We also describe evidence that a Caenorhabditis elegans orthologue of the mammalian 2OST enzyme, called HST-2, is essential for the normal development of this nematode. Together, these studies emphasize the importance of HSSTs in the biosynthesis of functionally variant HS proteoglycans, and demonstrate the importance of these complex regulatory molecules in developmental processes.