IFN-gamma enhances macromolecular transport across Peyer's patches in suckling rats: implications for natural immune responses to dietary antigens early in life.

BACKGROUND: The capacity to generate (interferon-gamma) IFN-gamma, a potent immunoregulatory and inflammatory cytokine, is low in neonates and deficient in patients with food allergy. METHODS: We investigated the effect of IFN-gamma on antigen transport in the gut. In experiment I rat pups were randomized into two groups at the age of 14 days i.e., before gut maturation: Group IFN was given intraperitoneally recombinant rat IFN-gamma on days 14, 16, 18, 20. In experiment II, rats were randomized into two groups at the age of 26 days, i.e., after gut maturation: Group IFN received the IFN-gamma treatment on days 26, 28, 30, 32. Controls in both experiments received sterile saline. The absorption of horseradish peroxidase (HRP) across jejunal segments with and without Peyer's patches was studied in Ussing chambers on days 21 and 33 for experiments I and II, respectively. RESULTS: In experiment I, the absorption of intact HRP across both types of segments was significantly increased in Group IFN compared to controls. The mean (95% confidence interval) rate of degraded HRP absorption across patch-containing segments in Group IFN was significantly greater than in controls, 4420 (3162-6179) ng.h-1.cm-2 in comparison to 1550 (633-3790) ng.h-1.cm-2; F = 8.96, p = 0.009. CONCLUSION: IFN-gamma increases macromolecular transport before gut maturation particularly across Peyer's patches. This Peyer's patch-targeted effect can be important eliciting mucosal immune responses against dietary antigens early in life and aiding their immune exclusion.

Early clinical symptoms and incidence of aspartylglucosaminuria in Finland.

Early clinical symptoms were analyzed from all known 43 children with aspartylglucosaminuria, born during 1974-1989 in Finland. Pre- and perinatal histories appeared normal for all children, except for muscular hypotonia and weak sucking in some babies. Three infants had abduction stiffness in the hips, needing follow-up. Other abnormalities found in infancy were umbilical or inguinal hernias and unusual susceptibility to respiratory and ear infections. This susceptibility diminished clearly in most patients after six years of age. Episodic diarrhea, described earlier, appeared to be a rather infrequent symptom and a less valuable diagnostic clue. New clinical phenomena were talipes planovalgus or clubfoot, needing surgical treatment, and aggressive behavior, needing, occasionally, child psychiatric consultation or treatment. In addition, angiokeratoma of the skin, not an infrequent phenomenon among adult patients, was found in one child. The main indications for further studies were delayed speech, attention deficit and clumsy or delayed motor functions. The disease is easily misdiagnosed and, universally, probably underdiagnosed. Its incidence in Finland was recalculated and appeared to be at least 1 in 18,500 live-born babies in this country.

Autophagic vacuoles fuse with the prelysosomal compartment in cultured rat fibroblasts.

We previously demonstrated both mannose 6-phosphate receptor (MPR) and cathepsin L in early autophagic vacuoles of cultured rat fibroblasts. This suggested that the enzyme may originate either from the receptor-enriched prelysosomal compartment (PLC) or from the trans-Golgi network (TGN). In the present ultrastructural study, we elucidated the roles of the PLC and TGN in lysosomal enzyme delivery to autophagic vacuoles. Firstly, we studied whether endocytic markers, cationized ferritin (CF), bovine serum albumin-gold or horseradish peroxidase (HRP), can be detected in autophagic vacuoles. Autophagy was induced by serum removal from the medium with or without leupeptin, an inhibitor of cysteine proteinases. Endocytic markers were not detected in autophagic vacuoles after short uptake which filled the early endosome, but only after longer labeling which filled the PLC. The markers were usually found in advanced autophagic vacuoles containing partially degraded cytoplasm and complex internal membranes which are the characteristic of the PLC. HRP-positive vesicles were also observed in continuity with early autophagic vacuoles containing intact cytoplasm. After uptake and transport of CF and HRP to the PLC, these markers were delivered to autophagic vacuoles even if microtubules were disrupted in vinblastine before the induction of autophagy. Secondly, we studied whether MPRs transport cathepsin L to autophagic vacuoles directly from the TGN. Two inhibitors of MPR-mediated enzyme transport, tunicamycin and chloroquine, were used. Quantitative immunocytochemistry showed that neither of these drugs prevented cathepsin L delivery to autophagic vacuoles. The results suggest that a large proportion of lysosomal enzymes is delivered to autophagic vacuoles from the PLC by a microtubule-independent manner. The first enzymes may be transported in small PLC-derived vesicles or tubules which are reached by HRP but not by CF and gold. Later, the autophaged cytoplasm is delivered to larger vacuolar parts of the PLC. Mannose 6-phosphate receptors transport no or only trace amounts of lysosomal enzymes to autophagic vacuoles directly from the TGN.

Epileptic seizures in aspartylglucosaminuria: a common disorder.

Aspartylglucosaminuria (AGU) is a lysosomal storage disorder with reduced life-span. An analysis of 121 Finnish patients showed that 22 to 78 adults (28%) and one of 43 children (2%) had epileptic seizures. Twelve patients had the onset of attacks after the age of 30 years. Eleven patients had generalized, nine partial and three unclassified seizures. The response to carbamazepine was good. The major interictal EEG abnormality was the attenuation of the amplitude found in 10/27 patients. The brain CT-scans showed diffuse atrophy in 8/11 patients.

Autophagy, cathepsin L transport, and acidification in cultured rat fibroblasts.

The mechanisms of enzyme delivery to and acidification of early autophagic vacuoles in cultured fibroblasts were elucidated by cryoimmunoelectron microscopic methods. The cation-independent mannose-6-phosphate receptor (MPR) was used as a marker of the pre-lysosomal compartment, and cathepsin L and an acidotropic amine (3-(2,4-dinitroanilino)-3'-amino-N-methyl-dipropylamine (DAMP), a cytochemical probe for low-pH organelles) as markers of both pre-lysosomal and lysosomal compartments. In addition, cationized ferritin was used as an endocytic marker. In ultrastructural double labeling experiments, the bulk of all the antigens was found in vesicles containing tightly packed membrane material. These vesicles also contained small amounts of endocytosed ferritin and probably correspond to the MPR-enriched pre-lysosomal compartment. Some immunolabeling was also visible in the trans-Golgi network. In addition, cathepsin L, DAMP, and large amounts of ferritin were found in smaller vesicles which can be classified as mature lysosomes. Early autophagic vacuoles were defined as vesicles containing recognizable cytoplasm. MPR, cathepsin L, and DAMP, but not ferritin, were detected in the early vacuoles. Inhibition of the acidification in the early vacuoles by monensin did not prevent the delivery of MPR and cathepsin L. The presence of MPR in the vacuoles suggests that cathepsin L is not delivered to early autophagic vacuoles solely by fusion with mature, MPR-deficient lysosomes. Furthermore, although lysosomes were loaded with endocytosed ferritin, it was not detected in autophagic vacuoles. Either the trans-Golgi network or the MPR-enriched pre-lysosomes may be the main source of enzymes and acidification machinery for the autophagic vacuoles in fibroblasts.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood dolichol in lysosomal diseases.

Highly elevated serum total dolichol (free dolichol + dolichyl ester) concentrations have recently been found in two lysosomal storage diseases, aspartylglucosaminuria (AGU) and mannosidosis. The present study demonstrates that the increase of serum dolichol in AGU patients is caused by an increase of serum free dolichol. In 15 patients the mean serum level of free dolichol (227 +/- 16 ng/mL) was 1.9 times higher (p < 0.001) than that in healthy controls (120 +/- 6 ng/mL), while the amounts of dolichol fatty acid esters were similar in the patients and controls (110 +/- 9 vs. 118 +/- 6 ng/mL). In contrast, 10 patients with neuronal ceroid-lipofuscinosis (NCL) (three with infantile, four with juvenile, and three with variant late infantile NCL) had significantly (p < 0.01) lower mean serum levels of both free (79 +/- 5 ng/mL) and total (159 +/- 6 ng/mL) dolichol than age-adjusted healthy controls (free, 100 +/- 6 ng/mL; total, 206 +/- 14 ng/mL). Decreased blood dolichol has not been reported earlier for any other disease. We conclude that the increased serum free dolichol in AGU reflects disturbed lysosomal function and that the decreased free and esterified dolichols in NCLs speak against their presumed primary lysosomal nature.

Serum lipids and lipoproteins during therapeutic amenorrhea induced by lynestrenol and depot-medroxyprogesterone acetate.

Serum concentrations of total cholesterol, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), triglyceride (TG), apolipoprotein A1 (Apo A1), and apolipoprotein B (Apo B) were determined in mentally handicapped subjects (n = 87). 33 women were on lynestrenol 5-10 mg for therapeutic amenorrhea (TA). 18 of them were randomly allocated to continue on lynestrenol and 15 were switched to intramuscular administration of medroxyprogesterone (DMPA). The switch to DMPA resulted in significant increases in HDL-C (33%), Apo A1 (12%), as well as in the HDL-C/LDL-C (48%) and Apo A1/Apo B (22%) ratios. The concentrations of HDL-C and Apo A1 were significantly greater in patients receiving DMPA, than in patients continuing with lynestrenol therapy. The amenorrhea incidence, however, did not differ between the two therapy groups. It is concluded that therapy with DMPA may be associated with smaller atherosclerosis risk than with peroral lynestrenol, because of its weaker effect on HDL-C and A1 levels.

Elevated levels of serum dolichol in aspartylglucosaminuria.

Slightly elevated serum dolichol levels have so far been demonstrated only in alcoholics. We now report two diseases with exceptionally high serum dolichol levels. They are autosomal, recessively inherited lysosomal storage diseases, aspartylglucosaminuria (AGU) and mannosidosis. In 16 patients with AGU the mean serum level of total dolichols (457 +/- 43 ng/ml) was more than two-fold when compared to healthy controls (170 +/- 4 ng/ml). In two patients with mannosidosis the levels were almost two-fold. The percentage distribution of the dolichol homologues with 18, 19 or 20 isoprene units did not differ between the patients and controls. The inclusion of an additional control group excluded the possible influence of mental retardation and imparied moving ability on the results. Elevated serum dolichols in patients with lysosomal storage diseases may reflect a disturbance in lysosomal function and serve as a diagnostic marker. The biochemical mechanisms leading to this phenomenon remain to be established.

Pyrazole is different from acetone and ethanol as an inducer of the polysubstrate monooxygenase system in mice: evidence that pyrazole-inducible P450Coh is distinct from acetone-inducible P450ac.

The induction of liver microsomal monooxygenase activities elicited by pyrazole, ethanol, and acetone, all shown to be inducers of rat P450j and rabbit P450LM3a, has been compared in inbred strains of DBA/2N, AKR/J, and Balb/c mouse. Pyrazole strongly increases coumarin 7-hydroxylase (COH) activity in DBA/2N but much less in other strains. The effect of pyrazole on aniline p-hydroxylase and ethanol oxidase activities is also strain dependent: an increase was seen only in the DBA/2N strain. Ethanol and acetone were unable to induce COH, whereas aniline p-hydroxylase and ethanol oxidase were elevated about 1.4- to 3.3-fold in all strains. No strain difference could be detected in aniline p-hydroxylase or ethanol oxidase inducibility. There was a strong correlation between aniline p-hydroxylase and ethanol oxidase activities in every strain, whereas no positive correlation could be found between COH and aniline p-hydroxylase activities. Immunoinhibition experiments showed that a polyclonal antibody against purified pyrazole-inducible COH (P450Coh) blocked about 90% of COH activity, but only about 10% of aniline p-hydroxylase or ethanol oxidase in mouse liver microsomes. Monoclonal antibody 1-91-3 (raised against rat acetone-inducible P450ac) did not inhibit COH, whereas aniline p-hydroxylase was blocked 46-76% and ethanol oxidase 25-70%, depending on the source of microsomes. In immunoblots, anti-P450Coh recognized only its own antigen but not the P450ac, whereas monoclonal antibody 1-98-1 against P450ac detected P450ac and a corresponding form in the D2 mouse liver, but not the P450Coh. The purified P450ac and P450Coh had molecular masses of 52 and 50 kDa, respectively, on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. These antigens were expressed differentially in response to pyrazole, ethanol, and acetone: P450Coh was increased only after pyrazole treatment, but 1-98-1-detectable protein was elevated in D2 mouse liver microsomes by ethanol and acetone, but not by pyrazole. We conclude that mouse P450Coh and rat P450ac are not corresponding forms of the same isozyme, and that a P450ac-like protein, responsible for most of aniline p-hydroxylation and ethanol oxidation, is present in the D2 mouse liver. These two P450 isozymes are also dissimilarly expressed in the mouse liver in response to inducer administration.

Clinical features in a de novo interstitial deletion 15q13 to q15.

A boy with several dysmorphic features and suffering from mental and motor retardation was found to have a de novo interstitial deletion of chromosome 15, involving bands q13 to q15. His clinical picture is described and compared with the clinical features reported in other deletions of this chromosome, located or extending distally from the region associated with Prader-Willi syndrome.

Peroral lynestrenol and arterial disease in mentally retarded women. A case-control study based on autopsy findings.

Autopsy findings from 170 non-smoking and mentally retarded women aged 12-51 years were analysed for any epidemiological association between the use of peroral lynestrenol for inducing therapeutic amenorrhea (TA) and arterial disease. Eighty-six women had received lynestrenol continuously for an average of 81 months (range 2-220 months) and the other 84 had not. After exclusion of 6 cases with known risk factors (diabetes, hypertension) predisposing to arterial disease, pathological arterial changes were found in 16 patients, 10 of them belonging to the TA group and 5 to the non-lynestrenol group. The incidence of arterial disease at autopsy at the age of 35 or more was 8/19 in TA patients and 1/15 in non-lynestrenol patients (p = 0.078). The benefits of prolonged TA induced by lynestrenol in this group of patients must be weighed very carefully against the possible risks involved.

Pyrazole as a modifier of liver microsomal monooxygenase in DBA/2N and AKR/J mice.

Effects of pyrazole on liver microsomal monooxygenase was studied in two inbred strains of mice, DBA/2N (D2) and AKR/J (AKR). A selective effect on microsomal monooxygenase was found. In the D2 mouse pyrazole strongly increases the coumarin 7-hydroxylase (CoH) and 7-ethoxycoumarin O-deethylase (ECDE) activities while on the total cytochrome P-450 (P-450) content and ethylmorphine N-demethylase (EMDM) and benzo(a)pyrene hydroxylase (AHH) activities the effect is biphasic (increased with lower doses and decreased with higher). For AKR the effect of pyrazole is different from the D2. The increase of CoH and ECDE is weaker and no biphasic effect for the other three parameters can be seen. Instead only a decrease takes place. The optimal dose of pyrazole for the induction of CoH in the D2 mice is 200 mg/kg once a day during three days. The effect of pyrazole is strongest in animals (D2) of 4-10 weeks old. For young animals (2 weeks old) no effect except of a weak decrease in AHH can be seen. Also for old animals the effect is weak. Recovery of the monooxygenase after pyrazole induction takes place in about 120 hr except for the total P-450 content which is still below normal. No sex dependence in the effect of pyrazole on CoH was found.

Prevalence of the fragile X syndrome in four birth cohorts of children of school age.

The prevalence of the fragile X syndrome among 12,882 children (6594 boys and 6288 girls) born during the years 1969-1972 in Kuopio province in eastern central Finland has been studied retrospectively. Mentally retarded children were selected from normal schools by using school achievement tests and from registers of mentally retarded individuals. In the present study fragile X syndrome was found in 6/111 mentally retarded children (5.4%), in 4/61 boys and in 2/50 girls, respectively. It was not detected in the control group of 85 healthy children. The corrected prevalence of fragile X syndrome among boys in four successive birth cohorts was estimated to be 1 in 1210 or 0.8/1000, and that among girls, 1 in 2418 or 0.4/1000. The overall prevalence was calculated to be 1 in 1612 or 0.6/1000 children.

Chromosomal aberrations in 85 mentally retarded patients examined by high resolution banding.

Eighty-five mentally retarded patients had their chromosomes examined by using the high resolution banding techniques. Fifty-nine of them had multiple congenital anomalies and/or dysmorphic features. Twenty-six had mental retardation but no major anomalies; they were primarily suspected of having the fragile X syndrome. This suspicion was first excluded. Fifteen patients were found to have a chromosome aberration, interpreted as clinically significant. Eleven of them had been examined earlier by conventional methods. The aberrations found were divided into three groups: (I) those detectable with an accuracy of ca. 300-400 bands (N = 4), (II) those detectable with an accuracy of ca. 400-550 bands (N = 6) and (III) those detectable with an accuracy of ca. 550-850 bands (N = 5). The aberrations are described and discussed.

Frequency of rare fragile sites among mentally subnormal schoolchildren.

The frequency of rare fragile sites was studied among 240 children in special schools for subnormal intelligence (IQ 52-85). 1/130 boys studied (0.8%) had the fragile site at Xq27.3 while it was not found in any girl (0/110). In two children an autosomal rare fragile site at 2q11.2 (2/240, 0.8%) was seen. In addition a constitutional chromosome abnormality was found in a further seven children (7/240, 2.9%).

Risk of hepatitis B in a ward for mentally retarded HBsAg carriers.

A screening of 615 mentally retarded residents in a Finnish institution revealed 22 HBsAg-positive asymptomatic carriers in 1972. Thirteen of them were placed in a special ward and followed up for 12 years. Only one patient had hepatitis eight years later. During the years all 52 staff members of the ward and the laboratory had been HBsAg-negative, but one laboratory nurse and two ward nurses showed antibody production. The seroconversion rate was one per 33 person-years among the staff. The results suggest that the risk of transmitting hepatitis B still exists, even in special wards in such institutions, and isolation of the carriers alone cannot guarantee full protection for hepatitis B infections.