Anaphylaxis to pine nut: cross-reactivity to Artemisia vulgaris?

The use of pine nuts, the seeds of Pinus pinea, is on the increasing in the modern Mediterranean diet. Little more than 20 cases of allergy to this tree nut have been published, and cross-reactivity with pine pollen, peanut and almond has already been reported. We describe the case of a young boy with several episodes of anaphylaxis after pine nut ingestion. Specific IgE to pine nut and Artemisia vulgaris was demonstrated by skin prick tests and in vitro determination of specific IgE, although no IgE to pine pollen or other nuts was detected. Immunoblotting of Artemisia vulgaris and pine nut revealed two matching diffuse bands, just below 14 kDa and 30 kDa. The ImmunoCAP inhibition assays showed complete inhibition of pine nut specific IgE after serum incubation with Artemisia vulgaris extract. As far as we know, this is the first reported case of documented cross-reactivity between pine nut and Artemisia vulgaris.

Quantitative analysis of immunoglobulin E reactivity profiles in patients allergic or sensitized to natural rubber latex (Hevea brasiliensis)

BACKGROUND

Characterized native and recombinant Hevea brasiliensis (rHev b) natural rubber latex (NRL) allergens are available to assess patient allergen sensitization profiles.

OBJECTIVE

Quantification of individual IgE responses to the spectrum of documented NRL allergens and evaluation of cross-reactive carbohydrate determinants (CCDs) for more definitive diagnosis.

METHODS

Sera of 104 healthcare workers (HCW; 51 German, 21 Portuguese, 32 American), 31 spina bifida patients (SB; 11 German, 20 Portuguese) and 10 Portuguese with multiple surgeries (MS) were analysed for allergen-specific IgE antibody (sIgE) to NRL, single Hev b allergens and CCDs with ImmunoCAP technology.

RESULTS

In all patient groups rHev b 5-sIgE concentrations were the most pronounced. Hev b 2, 5, 6.01 and 13 were identified as the major allergens in HCW and combined with Hev b 1 and Hev b 3 in SB. In MS Hev b 1 displayed an intermediate relevance. Different sIgE antibody levels to native Hevea brasiliensis (nHev b) 2 and rHev b 6.01 allowed discrimination of SB with clinical relevant latex allergy vs. those with latex sensitization. Sensitization profiles of German, Portuguese and American patients were equivalent. rHev b 5, 6.01 and nHev b 13 combined detected 100% of the latex-allergic HCW and 80.1% of the SB. Only 8.3% of the sera showed sIgE response to CCDs.

CONCLUSIONS

Hev b 1, 2, 5, 6.01 and 13 were identified as the major Hev b allergens and they should be present in standardized latex extracts and in vitro allergosorbents. CCDs are only of minor relevance in patients with clinical relevant latex allergy. Component-resolved diagnostic analyses for latex allergy set the stage for an allergen-directed immunotherapy strategy.

Does increased gender equality lead to a convergence of health outcomes for men and women? A study of Swedish municipalities

This study examines associations between indicators of gender equality and public health. We compare Swedish municipalities on nine indicators in both the private and public sphere, and an additive index, and study the correlations with indicators of morbidity and mortality. The hypothesis that a higher level of gender equality is associated with a convergence of health outcomes (life expectancy, sickness absence) between men and women was supported for equality of part-time employment, managerial positions and economic resources for morbidity, and for temporary parental leave for mortality. Our main finding is that gender equality was generally correlated with poorer health for both men and women. Our conclusions are tentative due to the methodological uncertainties. However, the results suggest an unfortunate trade-off between gender equality as we know it and public health. Sweden may have reached a critical point where further one-sided expansion by women into traditionally male roles, spheres and activities will not lead to positive health effects unless men also significantly alter their behaviour. Negative effects of this unfinished equality might be found both for women, who have become more burdened, and men, who as a group have lost many of their old privileges. We propose that this contention be confronted and discussed by policymakers, researchers and others. Further studies are also needed to corroborate or dispute these findings.

Treatment process for MSW combustion fly ash laboratory and pilot plant experiments

Fly ash from combustion of municipal solid waste sometimes contains large amounts of soluble salts, such as NaCl, even though the content of soluble toxic metal compounds is relatively low. Removal of the salts by washing with water has been suggested as a method to increase the stability of this type of ash. In the work presented here, a simple washing process was studied and evaluated. The process includes three steps: leaching with water, filtration and displacement washing. Basic data were obtained in laboratory experiments and used in the construction of pilot plant equipment at a full size fluidized bed boiler, where a side-stream of the cyclone ash was treated. The process was designed to minimize the water consumption while obtaining an effective removal of salts and a stable ash residue. In order to achieve this, recirculation of leaching liquor was used and the displacement washing was adjusted to become close to ideal. The results showed that an ash/water slurry with a liquid to solid ratio as low as 3 could be handled without difficulty in the mixing, pumping and filtration units. Washing of the filter cake at a liquid to solid ratio of 0.5 removed the major part of the remaining dissolved salts in the pore liquid. About 90% of the chloride content was removed from the ash, whereas the contents of Na, K, Ca, Cd, Pb and a number of other minor elements were removed by 10-30%. Before treatment, the results of ash leaching tests were sometimes too high for chloride (2003/33/EC), but the treatment reduced the amount of soluble chlorides to far below the limit values. The leachability of most metals was reduced or unaffected by the ash treatment. For Na, K and Cl, it was less than 10% of the value for the untreated ash. However, the results showed that some ash components may be mobilized by the washing. Antimony is the most important due to its toxicity.

Simultaneous exposure of several allergens has an additive effect on multisensitized basophils

BACKGROUND

Patients immunoglobulin (Ig)E-sensitized to more than one allergen in their environment often have more symptoms than mono-sensitized individuals, which indicates that the allergens may have an additive effect. In order to study if such an effect could be detected on the inflammatory, cellular level, multisensitized basophils were challenged with various dose combinations of two relevant allergens.

METHODS

Basophils from patients IgE-sensitized to timothy/cat, birch/cat, timothy/mite and cat/mite were challenged with serial dilutions of different combinations of the two allergens. The basophil response was measured as CD63 expression analysed by flow cytometry.

RESULTS

The doses of each allergen in the pair had an additive effect resulting in a shift of the dose-response curve to higher CD63 percentages and higher CD-sens.

CONCLUSIONS

If a patient has IgE antibodies and thus sensitized basophils to more than one allergen, to which he is simultaneously exposed, the additive effect should be considered. Even low concentrations of IgE antibodies could be of clinical relevance in such a situation.

A critical assessment of allergen component-based in vitro diagnosis in cherry allergy across Europe

BACKGROUND

Food allergy to cherry occurs throughout Europe, typically with restricted oral reactions in the central and northern parts but with frequent systemic reactions in the Mediterranean region. Previous studies have demonstrated insufficient sensitivity of commercially available cherry extract reagents in the diagnosis of cherry allergy.

OBJECTIVE

To assess the diagnostic performance of specific IgE tests based on recombinant cherry allergens in comparison with an extract-based assay and to skin prick test (SPT). A secondary objective was to analyse the frequency of systemic reactions in cherry-allergic subjects across Europe, including the largest population of LTP-sensitized subjects from central Europe studied to date.

METHODS

A total of 186 subjects from central Europe and Spain were studied. Serum IgE was analysed with ImmunoCAP tests carrying rPru av 1, 3 and 4, combined and separately, and cherry extract.

RESULTS

Among the central European cherry allergics, the mix of rPru av 1, 3 and 4 had a sensitivity of 95%, compared with 65% for cherry extract, and the IgE binding capacity of the recombinant mix was considerably higher. The sensitivity of the two tests was more comparable in the Spanish population, 95% and 86%, respectively. The recombinant allergen ImmunoCAP equalled SPT in terms of sensitivity and specificity. Consistent with previous reports, major geographic differences in sensitization pattern and prevalence of systemic reactions were found. A significantly higher rate of systemic reactions was found in Spanish patients sensitized to Pru av 3 whereas German patients sensitized to LTP only had oral allergy syndrome.

CONCLUSIONS

The recombinant cherry allergen ImmunoCAP is a highly sensitive diagnostic tool, clearly superior to any diagnostic method based on cherry extract. Three cherry allergens are sufficient for detecting sensitization in 95% of cherry-allergic subjects. Systemic reactions are common in LTP-sensitized individuals but seem to require at least one additional causative factor.

Parental share in public and domestic spheres: a population study on gender equality, death, and sickness

STUDY OBJECTIVE

Examine the relation between aspects of gender equality and population health based on the premise that sex differences in health are mainly caused by the gender system.

SETTING/ PARTICIPANTS

All Swedish couples (98 240 people) who had their first child together in 1978.

DESIGN

The exposure of gender equality is shown by the parents' division of income and occupational position (public sphere), and parental leave and temporary child care (domestic sphere). People were classified by these indicators during 1978-1980 into different categories; those on an equal footing with their partner and those who were traditionally or untraditionally unequal. Health is measured by the outcomes of death during 1981-2001 and sickness absence during 1986-2000. Data are obtained by linking individual information from various national sources. The statistical method used is multiple logistic regressions with odds ratios as estimates of relative risks.

MAIN RESULTS

From the public sphere is shown that traditionally unequal women have decreased health risks compared with equal women, while traditionally unequal men tend to have increased health risks compared with equal men. From the domestic sphere is indicated that both women and men run higher risks of death and sickness when being traditionally unequal compared with equal.

CONCLUSIONS

Understanding the relation between gender equality and health, which was found to depend on sex, life sphere, and inequality type, seems to require a combination of the hypotheses of convergence, stress and expansion.

Health, wealth and fairness based on gender: the support for ethical principles

Sex differences in health, and the reality of a gender system, are well-known, but we know little about how this connects to opinions on fairness and desired change. This study aims to explore two principal questions: how to compare the position of women and men within-state and how to choose between-states, where a state is defined as a situation in which individuals have a particular set of resources, rights and duties, and if components in the set are altered, a new state for the same individuals appears. Based on various normative rules (monistic view or separate spheres, equity as choice or ethics of care, equity by attainment or shortfall; variants of welfarism, feminism and conservatism), a survey among Swedish public health workers was carried out. The results demonstrate a major rejection of the idea of compensation between health, power, influence and resources, and of considering past processes when judging fairness as to women and men. Moreover, most respondents believe that a biologically based difference in health is fair and reject health maximization as a guiding principle. The support for gender equality is strong when contrasted with the conservative goal, and subsists when contrasted against the Pareto criterion and trading-off health/income as well. Results that call for additional research and exchange of views include that common notions in research and policy-making are rejected by a majority, and that females and males differ considerably when judging change from a societal perspective.

High prevalence of IgE antibodies among blood donors in Sweden and Norway

BACKGROUND

Reactions after a blood transfusion could be allergic because of passive transfer of immunoglobulin E (IgE) antibodies from allergic donors.

AIMS OF THE STUDY

To compare spectrum and prevalence of IgE antibodies in blood donors from Sweden and Norway.

METHODS

Using the ImmunoCAP method, serum samples from 1002 blood donors from Sweden and 500 from Norway were analysed for IgE antibodies to common inhalant and food allergens and allergens common in a hospital environment, such as penicilloyl G and latex.

RESULTS

As many as 23.6-27.3% of the donors had IgE antibodies to at least one of the 14 allergens tested. Of these 6.8-16.7% had extremely high concentrations, i.e. >35 kU(A)/l corresponding to 100 times the cut-off for a positive allergy test. Most donors were sensitized to pollens, dander and mite but several had very high levels of IgE antibodies to penicilloyl G, latex and peanut. The pattern of sensitizing allergens differed between Sweden and Norway.

CONCLUSIONS

High serum levels of IgE antibodies to various allergens are common among blood donors and the degree of sensitization and spectrum of involved allergen varies between geographical regions. Present routines to identify IgE sensitized, potential risk, donors are not satisfactory; the sensitivity of selection procedures is about 25%.

Prevalence of IgE antibodies to morphine. Relation to the high and low incidences of NMBA anaphylaxis in Norway and Sweden, respectively

BACKGROUND

Anaphylactic reactions to a neuromuscular blocking agent (NMBA) is more than six times as common in Norway as in Sweden, probably due to differences in preoperative sensitization. The prevalence of IgE-sensitization to morphine (MOR) and suxamethonium (SUX) in comparable populations in Bergen, Norway, and Stockholm, Sweden, was studied and related to possible sensitizing agents.

METHODS

Three hundred sera of 'allergics' and 500 blood donors in Bergen and Stockholm were tested for IgE antibodies to MOR and SUX using Pharmacia Diagnostics ImmunoCAP(Uppsala, Sweden) assay and the results compared to those of 65 patients from Bergen with documented anaphylaxis to NMBA. In addition, 84 different household chemicals were tested, by IgE antibody inhibition, for SUX and MOR.

RESULTS

In Norway 0.4% of blood donors, 3.7% of allergics and 38.5% of anaphylactics were IgE-sensitized to SUX, and 5.0, 10.0 and 66.7%, respectively, to MOR. No serum from Sweden was positive. The majority of those sensitized (69%) were women. Several household chemicals contained SUX and/or MOR activity, but the only difference between Norway and Sweden was cough mixtures containing pholcodine (PHO). IgE antibodies to PHO were present in 6.0% of blood donors from Norway and in no serum from Sweden. Of the anaphylactics, 65-68% were sensitized to MOR or PHO but only 39% to SUX.

CONCLUSIONS

IgE-sensitization to SUX, MOR and PHO was detected in Norway but not in Sweden. One possible explanation is the unrestricted use of cough mixtures containing MOR derivatives in Norway.

Changes in height, weight, and body mass index in children with craniopharyngioma after three years of growth hormone therapy: analysis of KIGS (Pfizer International Growth Database)

Extreme degrees of obesity may occur in association with hypothalamic tumors, usually after surgical intervention. This phenomenon has been reported to occur in as many as 25-75% of children undergoing extensive surgical extirpation of craniopharyngiomas (Cranio). Because less is known about the auxology of children with Cranio with milder alterations in growth, we undertook a 3-yr longitudinal analysis, using the KIGS database (Pfizer International Growth Database), to study their growth patterns and evolution of weight. We compared the effect of GH therapy on height, weight, and body mass index (BMI) in 199 prepubertal children with diagnosed Cranio treated by surgery and/or radiotherapy to two other groups of children with other causes of organic GH deficiency (OGHD): one with postsurgical and/or postirradiated OGHD (OGHD + S/I; n = 92) and the other with OGHD not due to Cranio and not having undergone either surgery or irradiation (OGHD - S/I; n = 85). At the start of GH therapy, 1) mean chronological (P < 0.0001) and bone (P = 0.0002) ages were youngest in OGHD - S/I and oldest in OGHD + S/I; 2) the mean height sd score (SDS) was lowest in OGHD - S/I and comparably higher in the other two groups (P < 0.0001); 3) mean weight and BMI SDS were greatest in Cranio and least in OGHD - S/I (both P < 0.0001); and 4) the mean initial GH dose prescribed was highest in OGHD - S/I and comparable in the other two groups (P < 0.0001). After 3 yr of GH therapy, 1) mean bone age remained youngest in OGHD - S/I and oldest in OGHD + S/I (P < 0.0001); 2) mean height SDS was highest in Cranio and comparably lower in the other two groups (P = 0.0159); 3) mean weight and BMI SDS remained greatest in Cranio and least in OGHD - S/I (P < 0.0001 and P = 0.0003, respectively); and 4) the mean GH dose remained highest in the OGHD - S/I group and least in the Cranio group (P = 0.0082). There were statistically significant increases within each group between the start of treatment and after 3 yr of GH therapy in height and weight, but not in BMI SDS. Lastly, after 3 yr of GH treatment, children in the Cranio group continued to have disproportionately heavier weight and higher BMI (with the greatest values in those with lower stimulated peak GH concentrations) compared with members of the other two groups, with no salutary effect of GH treatment on weight SDS and a mild improvement in BMI SDS. After S/I treatment, children with Cranio are disproportionately prone to varying degrees of weight gain compared with children with other forms of OGHD. In the present cohort of prepubertal children with Cranio, GH therapy induced excellent linear growth, but failed to have an ameliorative effect on weight gain and had only a slight beneficial effect on BMI gain. Because affected children may have resultant significant long-term medical morbidity and diminished quality of life, it is critical that the mechanism of this phenomenon be determined to devise helpful preventive or therapeutic interventions.

A population study of the association between hospitalization for alcoholism among employees in different socio-economic classes and the risk of mobility out of, or within, the workforce

BACKGROUND

Alcohol problems can increase the risk of downward mobility within, or mobility out of, the workforce. The magnitude of this risk has been unclear, as has also been the question whether the risk is different for men and women, for different socio-economic classes, and for single-living compared with co-habiting people.

METHODS

The study period was 1970-1980, when unemployment was low in Sweden. Information about socio-economic status from censuses was linked to hospitalization for alcoholism, alcohol psychosis and alcohol intoxication (AAA) over the period 1970-1975 in Stockholm County in persons aged 20-49 years in 1970 and gainfully employed in the same socio-economic category in both 1970 and 1975, and to general population data. The standardized rate ratio for mobility out of the workforce and for downward socio-economic mobility was calculated for those hospitalized with AAA.

RESULTS

There was a statistically significant risk of mobility out of the workforce over the period 1976-1980 in both sexes and in all socio-economic groups. The relative risk was 6.63 for male skilled and semi-skilled manual workers and 9.52 for non-manual employees at medium and high level, while the corresponding figures were lower for women. The absolute risk of leaving the workforce was lowest in non-manual employees at medium and high level. The relative risk was reduced in persons who were co-habiting.

CONCLUSIONS

Severe alcohol problems are powerful determinants of downward mobility within, or mobility out of, the workforce in both sexes and in all socio-economic categories.

Is the association between short stature and myocardial infarction explained by childhood exposures--a population-based case referent study (SHEEP)

AIMS

This study was undertaken to examine the association between short stature and acute non-fatal myocardial infarction and to analyse causal mechanisms related to height with a focus on childhood risk factors.

METHOD

The SHEEP (Stockholm Heart Epidemiology Program) is a population-based case-referent study. The outcome was incident first events of myocardial infarction. The study base included all Swedish citizens aged 45 to 70, who lived in Stockholm County during 1992-94. This analysis is based on 967 male cases, 412 female cases and 1696 referents. Exposure information was obtained through questionnaires, interviews, health examinations, and obstetric records.

RESULTS

Adult height was inversely related to myocardial infarction. The odds ratio for men in the shortest quartile (< 173 cm) compared with the tallest was 1.78 (95% CI: 1.39, 2.28). For women the corresponding odds ratio in the shortest quartile (<159 cm) was 1.86 (95% CI: 1.28, 2.71). Height was also inversely associated with fetal growth and indicators of material resources during childhood. Within each social class of origin short stature was associated with number of siblings, lack of higher education, and absence of upward social mobility. Adjustment for childhood risk factors decreased the excess relative risk of short stature with around 25%. Adult social, behavioural, and biological risk factors could not explain the association. The findings were similar for men and women.

CONCLUSION

Height is associated with many risk factors of myocardial infarction, which increase the risk of disease through many different causal pathways. Childhood exposures have no dominant role in explaining the association between short stature and myocardial infarction.

Molecular cloning, purification, and IgE-binding of a recombinant class I chitinase from Hevea brasiliensis leaves (rHev b 11.0102)

BACKGROUND

Class I chitinase in natural rubber latex (NRL) has been assumed to be an important allergen, especially concerning its cross-reactivity with fruits like avocado and banana.

OBJECTIVES

The present study aimed to produce a recombinant latex class I chitinase from Hevea brasiliensis leaves and to study its immunoglobulin (Ig)E-binding reactivity.

METHODS

A class I chitinase-specific complementary DNA from H. brasiliensis leaves was synthesized, subcloned, sequenced and overexpressed in fusion with the maltose-binding protein (MBP) in Escherichia coli. The IgE-binding reactivity of this protein was studied by the Pharmacia CAP System and by immunoblot experiments using sera from latex-allergic patients.

RESULTS

The rHev b 11.0102 was found to have a length of 295 amino acid residues and contains an N-terminal hevein-like domain with a 56% homology to hevein. Analysis by the CAP method revealed the presence of rHev b 11.0102-specific IgE antibodies in 17 of 58 sera (29%) of IgE-mediated latex-allergic subjects tested. Immunoblot analysis of the MBP-rHev b 11.0102 fusion protein and the MBP carrier protein as a negative control confirmed the IgE-reactivity of rHev b 11.0102.

CONCLUSION

Due to its IgE-reactivity rHev b 11.0102 represents an allergen of intermediate prevalence in NRL. Its property to cross-react with certain fruits makes it an important supplement in the diagnostic panel of recombinant NRL allergens.

Control of hepatitis A through routine vaccination of children

CONTEXT

The impact of routine hepatitis A vaccination of children living in large communities with elevated disease rates has not been evaluated.

OBJECTIVE

To determine the effect of routine vaccination of children on disease incidence in a community with recurrent hepatitis A epidemics.

DESIGN, SETTING, AND PARTICIPANTS

Community-based demonstration project conducted from January 12, 1995, through December 31, 2000, in Butte County, California, among children aged 2 to 17 years.

INTERVENTION

In 1995, vaccination was offered to children aged 2 to 12 years during vaccination clinics conducted on 2 occasions 6 to 12 months apart at most schools in the county. In 1996-2000, vaccine was distributed to community health care clinicians, who vaccinated eligible children without charge. Vaccine was also available at health department clinics, selected child care centers, and other sites.

MAIN OUTCOME MEASURES

Hepatitis A vaccination coverage, hepatitis A incidence, and vaccine effectiveness.

RESULTS

During the study period, 29 789 (66.2%) of an estimated 44 982 eligible children received at least 1 vaccine dose; 17 681 (39.3%) received a second dose. The number of hepatitis A cases among the entire county population declined 93.5% during the study period, from 57 cases in 1995 to 4 in 2000, the lowest number of cases reported in the county since hepatitis A surveillance began in 1966. The 2000 incidence rate of 1.9 per 100 000 population was the lowest of any county in the state. Of the 245 cases reported during the 6-year period, 40 (16.3%) occurred among children 17 years of age or younger, of which 16 (40%) occurred in 1995 and only 1 in 2000. One of the 27 case patients eligible for vaccination had been vaccinated, having received the first dose 3 days before symptom onset. The estimated protective vaccine efficacy was 98% (95% confidence interval, 86%-100%).

CONCLUSIONS

In this population, hepatitis A vaccine was highly effective in preventing disease among recipients. Childhood vaccination appears to have decreased hepatitis A incidence among children and adults and controlled the disease in a community with recurrent epidemics.

Cadmium exposure and end-stage renal disease

Environmental exposure to cadmium may cause kidney damage and tubular proteinuria. We investigated the relationship between low-level cadmium exposure and end-stage renal disease (ESRD), indicated by renal replacement therapy (RRT), in a Swedish population environmentally or occupationally exposed to cadmium. Based on records of all persons in the population previously or presently employed in cadmium-battery production or residing in cadmium-polluted areas near the battery plants, we defined exposure as high (occupational), moderate (domicile < 2 km from a plant), low (domicile 2 to 10 km from a plant), or no exposure (domicile > 10 km from a plant). Comprehensive data were available for all individuals undergoing RRT since 1978. The annual incidence of RRT increased from 41 per million in the age group 20 to 29 years to 243 per million in the age group 70 to 79 years and was greater in a priori-defined populations with cadmium exposure. Adjusting for age and sex gave an increased Mantel-Haenszel rate ratio (MH-RR) of 1.8 (95% confidence interval [CI], 1.3 to 2.3) for RRT in the cadmium-exposed population compared with the unexposed group; the MH-RR was even higher for women (MH-RR, 2.3; 95% CI, 1.5 to 3.5). Directly age-standardized rate ratios for RRT and cadmium exposure increased from 1.4 (95% CI, 0.8 to 2.0) in the low-exposure group to 1.9 (95% CI, 1.3 to 2.5) and 2.3 (95% CI, 0.6 to 6.0) in the moderate- and high-exposure groups, respectively. We conclude that exposure to occupational or relatively low environmental levels of cadmium appears to be a determinant for the development of ESRD.

Cloning and expression of a novel human glutaredoxin (Grx2) with mitochondrial and nuclear isoforms

Glutaredoxin (Grx) is a glutathione-dependent hydrogen donor for ribonucleotide reductase. Today glutaredoxins are known as a multifunctional family of GSH-disulfide-oxidoreductases belonging to the thioredoxin fold superfamily. In contrast to Escherichia coli and yeast, a single human glutaredoxin is known. We have identified and cloned a novel 18-kDa human dithiol glutaredoxin, named glutaredoxin-2 (Grx2), which is 34% identical to the previously known cytosolic 12-kDa human Grx1. The human Grx2 sequence contains three characteristic regions of the glutaredoxin family: the dithiol/disulfide active site, CSYC, the GSH binding site, and a hydrophobic surface area. The human Grx2 gene, located at chromosome 1q31.2--31.3, consisted of five exons that were transcribed to a 0.9-kilobase human Grx2 mRNA ubiquitously expressed in several tissues. Two alternatively spliced Grx2 mRNA isoforms that differed in their 5' region were identified. These corresponded to alternative proteins with a common 125-residue C-terminal Grx domain but with different N-terminal extensions of 39 and 40 residues, respectively. The 125-residue Grx domain and the two full-length variants were expressed in E. coli and exhibited GSH-dependent hydroxyethyl disulfide and dehydroascorbate reducing activities. Western blot analysis of subcellular fractions from Jurkat cells with a specific anti-Grx2 antibody showed that human Grx2 was predominantly located in the nucleus but also present in the mitochondria. We further showed that one of the mRNA isoforms corresponding to Grx2a encoded a functional N-terminal mitochondrial translocation signal.