Lp(a) lipoprotein/pre-ß1-lipoprotein in Swedish middle-aged males and in patients with coronary heart disease

A strong, positive association (P smaller than 0.0001) was found between the presence in serum of pre-beta1-lipoprotein upon electrophoresis in 0.5% agarose and the Lp(a+) phenotype in a series of 103 males aged 50-52 years participating in a health control study and in a series of 58 patients with sustained myocardial infarction. Both lipiprotein phenomena were more prevalent in the 58 patients than in the 103 presumably healthy males. The lack of any significant difference between total cholesterol values in the patients and the controls, despite the higher frequency of phenotype Lp(a+) in the former group, argues against the suggestion by Walton et al. (1974) that the increased Lp(a+) frequency in patients with coronary artery disease may be caused by a general increase in the concentration of low density lipoproteins (LDL).     

Lp(a) Lipoprotein/pre-β1-lipoprotein, serum lipids and atherosclerotic disease

With appropriate electrophoretic techniques and fresh serum samples, the Lp(a) lipoprotein/pre-beta1-lipoprotein is demonstrable as a distinct zone in the area between beta-lipoprotein and ordinary pre-beta-lipoprotein, when sera which are strongly positive with respect to the Lp(a) antigen are analyzed. The Lp(a) lipoprotein is a genetically determined normal serum component. The phenotype Lp(a+) was found significantly more frequently in two series of patients with coronary heart disease (CHD) than in appropriate controls. The frequency difference between patients and controls was particularly pronounced for the Finnish samples studied, 55% of the patients having the phenotype Lp(a+), as opposed to only 31% of the healthy controls. As judged from electrophoresis strips, hibh concentrations of Lp(a) lipoprotein/pre-beta1-lipoprotein were positively correlated with coronary score as determined by angiography. This correlation was highly significant. Total serum cholesterol value was slightly higher in Lp(a+) than in Lp(a-) persons from two of the four population samples studied, but no statistically significant difference was found. Serum triglyceride levels exhibited a statistically insignificant trend towards higher values in Lp(a-) than in Lp(a+) individuals, in three of the four samples tested. The strong association between the phenotype Lp(a+) and CHD, as well as the correlation between high amounts of Lp(a) lipoprotein/pre-beta1-lipoprotein and coronary score on one hand, and the weak correlation between presence of Lp(a) lipoprotein/pre-beta1-lipoprotein and lipid values on the other, make it highly unlikely that the increased frequency of the Lp(a+) phenotype in CHD patients merely reflects an over-all increase of the intravascular pool of LDL and/or VLDL reflected in increased serum levels of cholesterol and/or triglycerides. By the same token, it is unlikely that the insignificant effect on lipid values can, on its own, explain the correlation between Lp(a) phenotype and CHD.     

Lp(a) lipoprotein and pre-β1-lipoprotein in patients with coronary heart disease

Certain properties of the atypical serum lipoprotein, referred to as pre- β ₁-lipoprotein, suggested that it might be identical to the lipoprotein carrying the Lp(a) antigen: Lp(a) lipoprotein. Both lipoprotein phenomena are under genetic control and occur in a certain proportion of healthy people. Pre- β ₁-lipoprotein occurs more frequently in patients with coronary heart disease (CHD) than in the healthy population.
The present study of Finnish CHD patients was undertaken to investigate whether a close relationship could be revealed between pre- β ₁-lipoprotein and Lp(a) lipoprotein, as well as between Lp(a) lipoprotein and CHD. Both expectations were realised, and we conclude that pre- β ₁-lipoprotein is very closely related, if not identical to Lp(a) lipoprotein.
If the present results are confirmed in future studies, serum analysis for Lp(a) lipoprotein/pre- β ₁-lipoprotein may become a useful tool for the identification in early life of members of a subpopulation which is particularly at risk for developing CHD.     

Plasma concentrations of Lp(a) lipoprotein and TGF-β1 are altered in preeclampsia

This study was performed to investigate the possible association between preeclampsia and the plasma concentrations of Lp(a) lipoprotein and TGF-β₁ in a large series of patients. Additionally, correlation between the concentrations of these molecules and the severity of preeclampsia or fetal growth retardation was evaluated. Following clinical examination and biochemical analyses, both electroimmunoassay and RIA technique were used for quantitative determinations of plasma Lp(a) lipoprotein. ELISA technique was used to measure the active form of TGF-β₁ in plasma of pregnant normotensive and preeclamptic women. We examined 154 women with preeclampsia (preeclampsia group) and 76 healthy, pregnant normotensive women (control group). The preeclampsia group was further divided into the following subgroups: mild preeclampsia, severe preeclampsia and preeclampsia with fetal growth retardation. Plasma levels of Lp(a) lipoprotein were lower in the total preeclampsia group as well as in all preeclampsia subgroups (5.45 ± 7.41, 5.58 ± 8.02, 5.08 ± 5.38, and 4.32 ± 5.28 mg/dl in the total preeclampsia group, and in subgroups with mild preeclampsia, severe preeclampsia, and preeclampsia with fetal growth retardation, respectively) than in the control group (7.84 ± 9.26 mg/dl) as determined by quantitative electroimmunoassay. Corresponding results were obtained with a radioimmunoassay (166.03 ± 200.2 U/l in the total preeclampsia group vs. 229.18 ± 257.7 U/l in controls). There was good correlation between the two methods used for Lp(a) lipoprotein measurement. The differences between controls and the total preeclampsia group as well as each preeclampsia subgroup were statistically significant by a non-parametric test (one-way Kruskal-Wallis test). Plasma concentrations of the active form of TGF-β₁ were increased in all preeclampsia subgroups as well as in the total group (5.63 ± 1.68 ng/ml) compared to controls (4.67 ± 1.33 ng/ml). This increase in TGF-β₁ was statistically highly significant. Plasma concentrations of Lp(a) lipoprotein and the active form of TGF-β₁ did not differ significantly between the preeclampsia subgroups. The outcome of this study may suggest involvement of both parameters in the pathophysiology of preeclampsia and may substantiate the notion of a multifactorial etiology of the disease.     

Immunostaining for α1-antichymotrypsin and α1-antitrypsin in gliomas

Antisera to α₁-antichymotrypsin, α₁-antitrypsin and lysozyme were reacted with 20 cases of glioblastoma multiforme, seven anaplastic astrocytomas, eight astrocytomas, six oligodendrogliomas, four ependymomas and the cerebral cortex from six normal autopsy brains. In addition, two pleomorphic xantho-astrocytomas and two heavily lipidized malignant gliomas were similarly examined. All astrocytic lesions were confirmed with anti-GFAP antisera. Thirty astrocytic tumours (77%), four oligodendrogliomas (67%) and three ependymomas (75%) reacted positively with anti-α₁-antichymotrypsin; 25 astrocytic tumours (64%), three oligodendrogliomas (50%) and three ependymomas (75%) showed positive staining for α₁-antitrypsin. The pattern of staining with either of these two markers did not correlate with tumour grading. None of the gliomas examined stained positively with anti-lysozyme. Non-neoplastic glial elements did not react with any of the three antisera. The results of this study suggest that staining for α₁-antichymotrypsin and α₁-antitrypsin is of little value in the differential diagnosis of neuroepithelial or mesenchymal lesions in the brain.     

Further studies on serum α1-lipoprotein in familial lecithin:cholesterol acyltransferase deficiency

Serum high density lipoprotein (HDL) from two patients with LCAT deficiency has been compared with HDL from normal subjects and HDL from a presumed heterozygous carrier. By two different immunological methods the concentration of -lipoprotein in serum of the patients was found to he about 25–30 % of the normal concentration.
Patient HDL is cornpoked of two fractions, as shown previously. The first fraction contains particles of high molecular weight with an electrophoretic mobility slightly slower than that of normal HDL. The lipid content is 70%, and the concentrations of unesterified cholesterol and phospholipids are about 10–15 and 3–4 times that of normal HDL, respectively. The second fraction consists of particles of relatively low molecular weight with electrophoretic mobility faster than albumin. This fraction exhibits closc to normal concentrations of unesterified cholesterol and phospholipids. Esterified cholesterol or lysolccithin could he demonstrated in none of the fractions.
HDL from the prewmed hetcrozygous carrier was normal as judged from immunoelectro-phoresis, gel filtration, electron microscopy. and lipid analyses.     

Hepatocyte inclusions of δ1-antichymotrypsin in a patient with partial deficiency of δ1-antichymotrypsin and chronic liver disease

We present a case of chronic liver disease with selective and exclusive hepatocyte endoplasmic reticulum storage of alpha 1-antichymotrypsin in the form of granules, detected by specific immunohistochemistry at the light microscopy level and corresponding to material found in dilated endoplasmic reticulum of hepatocytes by electron microscopy. The patient had intermediate deficiency of alpha 1-antichymotrypsin. Thus, the hepatocyte accumulation of alpha 1-antichymotrypsin may indicate the presence of an export block resembling that of a closely-related protein, namely PiZ alpha 1-antitrypsin. It is proposed that hepatocyte storage of alpha 1-antichymotrypsin may be an expression of an inborn error of metabolism bearing the characteristics of endoplasmic reticulum storage diseases such as PiZ alpha 1-antitrypsin deficiency and hereditary hypofibrinogenaemia.     

Heterogeneous response of nasal and lung fibroblasts to transforming growth factor-β1

Background Nasal polyposis is characterized by marked oedema, sparse extracellular matrix (ECM) and proliferating blood vessels. Pulmonary fibrosis is characterized by inflammatory cells accumulation, considerable ECM deposition and vascular abnormalities. Although lung fibrosis is not only and necessarily an inflammatory disorder, we hypothesized that the difference between nasal polyposis and pulmonary fibrosis may, in part, be due to the heterogeneity between nasal and lung fibroblasts. Fibroblasts participate in the inflammatory response by releasing ECM proteins and cytokines. TGF‐β is thought to participate in chronic inflammation and fibrosis. Myofibroblasts are the activated form of fibroblasts. A phenotypic hallmark of myofibroblasts is the expression of smooth muscle α‐actin (SMA). Objective We examined whether there is any heterogeneity between nasal and lung fibroblasts upon stimulation with TGF‐β₁ with regard to the synthesis of SMA, pro‐collagen type I and vascular endothelial growth factor (VEGF) as well as translocation of Smad proteins. Methods Fibroblasts lines were established from human biopsy tissue. The expression of SMA, pro‐collagen type I, VEGF mRNA was evaluated by reverse transciptase RT‐PCR. The amount of pro‐collagen type I and VEGF was measured by ELISA. By immunocytochemistry, we analysed the expression of SMA and Smad2, 3, 4 in cultured fibroblasts. Results TGF‐β₁ induced SMA and pro‐collagen type I synthesis in lung, but not in nasal fibroblasts. By contrast, TGF‐β₁ induced VEGF synthesis in both lung and nasal fibroblasts. After stimulation with TGF‐β₁, Smad2, 3, 4 were translocated from the cytoplasm to the nucleus in lung fibroblasts, whereas only Smad3 was translocated in nasal fibroblasts. Conclusion These results establish the heterogeneous responsiveness of fibroblast populations in the airways to TGF‐β₁ and that such a heterogeneity may contribute, at least in part, to the different pathological outcomes of inflammation in the upper and lower airways.     

Heterozygous α-antichymotrypsin and PiZ (α1-antitrypsin deficiency

In a case-control study we compared the prevalence of heterozygous deficiency of two closely related anti-neutrophil protease inhibitors, alpha 1-antitrypsin and alpha 1-antichymotrypsin, in 172 consecutive children with asthma. In a cohort study the clinical spectrum and severity were compared. On the basis of family studies 5/172 (2.9%) were classified as heterozygotes for alpha 1-antichymotrypsin deficiency, a high prevalence compared with that of an unselected adult population (prevalence ratio 4.5 (1.7-11.9), P less than 0.005). This finding suggests that the carrier state of this rare allele (prevalence 0.64%) may predispose to asthma in children. Among these heterozygous patients the prevalence of positive RAST tests for foodstuffs was significantly increased (prevalence ratio 4.8 (1.7-13.2), P less than 0.005) and 2/5 manifested food allergy with Quincke oedema. Either the PiMZ or SZ phenotype of alpha 1-antitrypsin deficiency was found in 12 (7.0%) of the 172 patients, a prevalence similar to that of a normal population (prevalence ratio 1.3 (0.67-2.6), P = 0.44). However, the asthma was more severe among the Z allele carriers, judged by the number of hospital admissions, compared with the non-Z asthmatic children (mean 2.92 vs. 1.72, P less than 0.05). The results indicate that heterozygous deficiency of protease inhibitors directed against neutrophil proteases may affect the severity and clinical spectrum of childhood asthma, and to some degree be predisposing.     

Increased expression of collagen receptors: α1β1 and α2β1 integrins on blood eosinophils in bronchial asthma

BACKGROUND: Eosinophils are one of the major effector cells in bronchial asthma. Their infiltration of airways correlates with the asthma severity. Recruitment and activation of eosinophils are partially mediated by integrins alpha4beta1 and alpha4beta7. Collagens type I and IV constitute important components of extracellular matrix and vascular basement membrane, respectively. Therefore, collagen-binding integrins (alpha1beta1 and alpha2beta1) may also play a role in eosinophil lung infiltration. OBJECTIVE: To evaluate the possible presence of alpha1beta1 and alpha2beta1 integrins on peripheral blood eosinophils from asthmatic subjects. METHODS: Collagen receptors were studied on eosinophils separated by immunomagnetic CD16-negative method from healthy donors (n=13) and patients with moderate persistent atopic bronchial asthma (n=15). Surface receptor identification was performed by flow cytometry and cell adhesion assay. RESULTS: Eosinophils isolated from the patients showed increased expression of both alpha1beta1 and alpha2beta1 integrins as compared with healthy controls. Moreover, adhesive function of eosinophils to collagen type IV was inhibited by snake venom disintegrins: viperistatin and obtustatin. These disintegrins contain KTS active motif and are specific inhibitors of alpha1beta1 integrin. CONCLUSION: We demonstrated for the first time that collagen receptors: alpha1beta1 and alpha2beta1 integrins are overexpressed on the surface of peripheral blood eosinophils of asthmatic subjects. Further studies may reveal potential application of KTS-disintegrins or their structural analogs for therapy of bronchial asthma.     

Serial Measurements of Pregnancy-specific β1-glycoprotein (β1SP1) in Patients with Trophoblastic Disease

A radioimmunoassay for pregnancy-specific-β₁-glycoprotein (Bohn. 1971) has been established with a limit of detection of 2 μMg/litre in serum. The assay has been used to measure serial levels of pregnancy-specific-β₁-glycoprotein (β₁SP₁) in the serum of patients with choriocarcinoma and teratoma for comparison with measurements of the β-subunit of human chorionic gonadotrophin. The value of the assay for β₁SP₁, in the management of these patients is discussed.     

α1-antitiypsin deficiency and the flaccid lung syndrome

A significantly higher number of PI ZZ and PI MZ individuals was found in a flaccid lung population as compared to internal and healthy controls. The relative risk for ZZ is 12.5 and for MZ 1.8. We conclude that if a PI MZ individual does develop lung disease, the excess risk due to the deficiency is negligible compared to MM individuals and is highly influenced or modified by other factors, possibly including both environmental and genetic.     

Rapid genotyping of transforming growth factor β1 gene polymorphisms in a UK Caucasoid control population using the polymerase chain reaction and sequence-specific primers

Abstract: Transforming growth factor (TGF) β₁ is a growth factor which has multiple functions including the promotion of matrix deposition during wound healing and scar formation. Gene polymorphisms within or close to the 5' region of TGFβ₁ have been identified; three in the upstream region, one in the non-translated region, two in the signal peptide sequence and one in a region of the gene coding for the precursor protein. We have developed a method using 14 polymerase chain reaction-sequence-specific primer reactions to characterise six of these polymorphisms. In the upstream region, both forward and reverse allele-specific primers were used to demonstrate the cisltrans orientation of alleles at adjacent polymorphisms (haplo-types). We report the allele and genotype frequencies of TGFβ₁ genes in two sets of UK Caucasoid control subjects.;     

Complex segregation analysis of two principal components derived from horizontal and vertical head size traits

Background: There is a wealth of publications establishing the involvement of genetic factors in the determination of inter-individual variability of head size traits. However, little is known about the mode of inheritance of craniofacial traits in the healthy population.

Aim: The aims of this study were to investigate the mode of inheritance of horizontal (HOC) and vertical (VEC) components of head dimensions, and to test the hypothesis of a common major gene for these traits.

Subjects and methods: The study was conducted on 1406 individuals belonging to 357 pedigrees. Univariate and bivariate complex segregation analyses were conducted on two principal components, HOC and VEC, extracted from 10 original head traits.

Results: The hypothesis of Mendelian transmission was accepted in both studied traits. The inferred major genes explained 54.0% and 45.6% of HOC and VEC variance, adjusted for covariates. For both traits an additive mode of major gene alleles interaction was suggested. No positive evidence for a common major gene for both HOC and VEC was obtained.

Conclusion: We conclude that head size in horizontal and vertical dimensions is determined by two different major genes together with modest and minor effect genes, the latter being partly shared by HOC and VEC.     

Transforming growth factor-β1 and interleukin-10 in breast milk and development of atopic diseases in infants

BACKGROUND: Precise relationship between breastfeeding and infant allergy is poorly understood. Objective Aim was to quantify TGF-beta(1) and IL-10 in colostrum and mature milk from allergic and non-allergic mothers and to verify relationship with allergic disease development. METHODS: Mothers (13 allergics, nine controls) of 22 newborns participated to prospective study on development of children atopy. Colostrum and mature milk were assayed for TGF-beta(1) and IL-10 by ELISA. Children underwent paediatrician evaluation at 6 months of life. RESULTS: Data are presented as median values and range. A significant difference in concentration of TGF-beta(1) between colostrum (330, range 0-3400 pg/mL) and mature milk (215, range 0-2400 pg/mL) was observed in samples from allergic mothers (P=0.015). In mature milk TGF-beta(1) was significantly lower in allergic (215, range 0-2400 pg/mL) than in non-allergic mothers (1059, range 0-6250 pg/mL) (P=0.015). IL-10 was weakly expressed without significant differences between allergic (4.8, range 0-42 and 9.5, range 0-42 pg/mL in colostrum and in mature milk) and non-allergic mothers (0, range 0-42 pg/mL in colostrum and 0, range 0-42 pg/mL in mature milk). After 6 months 46% infants from allergic mothers, but none from controls, presented atopic dermatitis. CONCLUSION: TGF-beta(1) was significantly less secreted in mature milk of allergic mothers, while no difference in IL-10 was found. Particular cytokine patterns in milk could influence development of atopic diseases. Further immunological studies in this field are necessary.     

In vitro studies of the interaction of isolated Lp(a) lipoprotein and other serum lipoproteins with glycosaminoglycans

The interaction of isolated Lp(a) lipoprotein or other lipoprotein classes with different glycosaminoglycans (GAG) bound to activated Sepharose was studied. In contrast to LDL, the Lp(a) lipoprotein did not bind to the GAG tested if sodium was used as a buffer cation. In the presence of Ca++, however, even the Lp(a) lipoprotein was bound to GAG. This type of binding, probably mediated by divalent cation bridges, is apparently not a simple function of the GAG used. Addition of GAG in solution revealed that this binding may be the only one existing under physiological conditions, and it appears possible that the Lp(a) lipoprotein is bound more firmly to GAG than is LDL under such conditions.     

Further studies of Lp(a) lipoprotein/pre-β1,-lipoprotein in patients with coronary heart disease

The present study of 100 patients (46 of whom were included in a previous study) with suspected or proven coronary heart disease (CHD) confirms that Lp(a) lipoprotein and pre-beta1-lipoprotein are closely related, if not identical, and that Lp(a) lipoprotein/pre-beta-lipoprotein occurs more frequently in patients with CHD than in healthy people. Analysis of this lipoprotein component may have predictive value with respect to CHD.