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PubMedDate not supplied

Influence of genetic factors on the susceptibility to HBV infection, its clinical pictures, and responsiveness to HBV vaccination.

The association of genetic factors with hepatitis B virus (HBV) infection susceptibility, its different manifestations, and the different responses to hepatitis B antigen vaccination have been described by several authors. With regard to HLA class I molecules, association with HLA-B was especially observed.HLA-B35 and -B8 correlated with chronic active hepatitis (CAH)and with hepatitis B carriers. Correlation between HBV infection and HLA class II (loci DR and DQ)was also indicated, but results are not clear regarding the clinical pictures of the disease nor vaccination response. HLA class III (fourth complement component--C4,third complement component--C3, and properdin factor--BF) are associated with various manifestations of this disease. The gammaglobulin phenotype Gm (1,2,3,10,21)was more frequent in CAH. However, in only three publications was the impact of HLA on the efficacy of interferon therapy taken into account.

HLA Antigens↗
PubMed1990

[Diagnostic usefulness and prognostic value of inhibitory capacity and other biochemical parameters of plasma in acute pancreatitis in humans].

Assessment of the degree of severity of acute pancreatitis by means of biochemical parameters is still a subject of extensive studies. The purpose of the present study was a trial of evaluation of the diagnostic usefulness and prognostic value of certain tests for proteinase-anti-proteinase equilibrium and acute phase indices in acute pancreatitis in 52 patients (36 women and 16 men aged 22 to 83 years). The control group compared 29 healthy volunteers. The patients were classified according to the aetiology of the disease: pancreatitis connected with bile duct disease, alcoholic and non-classifiable, and another classification was based on the clinical course (medium severe, severe). Significantly higher concentration of immunoreactive trypsin (TLI) was found in the first two weeks in the group of severe disease as compared to the group with medium severe pancreatitis (p less than 0.01). TLI was significantly higher than in controls for 2 months after clinical recovery. The serum inhibitory capacity was significantly reduced in severe cases in relation to medium severe ones, particularly between 3 and 7 days of the disease (p less than 0.001). Similarly as trypsin concentration, reduced inhibitory capacity in relation to controls persisted for up to 2 months after pancreatitis. No significant differences were noted in the concentration of alpha 1 protease inhibitor and C3 and C4 complement components, in the studied groups. The serum alpha 2 macroglobulin level was significantly decreased between days 3 and 7 (p less than 0.05). The values of alpha 2 macroglobulin were correlated in that time with the values of the inhibitory capacity.

Acute Disease↗
PubMed1991

[The relationship between complement C3 receptors (CR1, CR3) on polymorphonuclear leukocytes and complement fragments during hemodialysis].

The expression of complement receptor type 1 (CR1) and type 3 (CR3) on polymorphonuclear leukocytes (PMNs) and generation of complement fragments, C3a, C5a, C4d, iC3b and Bb, were studied in patients during hemodialysis using cuprammonium rayon (Cu) membranes. Furthermore, the relation between the expression of CR1 and CR3 on PMNs from healthy donors and complement fragments was investigated. The expression of CR1 and CR3 on PMNs increased during hemodialysis. Plasma C3a, C5a and iC3b levels increased in the first 15 minutes and then decreased at 120 minutes of dialysis. But plasma Bb level remained high until the end of hemodialysis. Purified Bb had no effect on the expression of CR1 and CR3 on PMNs, but C5a augmented those expression in vitro. Nafamostat mesilate, an artificial proteinase inhibitor, inhibited augmentation of complement receptors on PMNs in concentration dependent fashion. C5a generated through the activation of complement was thought to take an important role in the increased expression of CR1 and CR3 on PMNs.

Aged↗
PubMed1991

[Circulating immune complexes and complement breakdown products in childhood IgA nephropathy].

Circulating immune complexes (CIC), mainly IgA-CIC have been frequently detected in IgA nephropathy and recently increased levels of C3 fragments which indicate C3 activation have been reported. However, little is known about the relationship between CIC and complement activation. We determined CIC by the solid-phase anti-C3 Facb enzyme immunoassay in 37 children with IgA nephropathy to investigate the relationship between CIC and clinical and/or histological findings, and also determined C3 fragments whether CIC correlate with complement activation. IgA-CIC were detected in 78% (27/37) with a mean level of 11.9 +/- 3.9 micrograms/ml, which was significantly higher than other glomerular diseases (P less than 0.05). IgA-CIC levels were also found significantly higher in 27 cases with proteinuria than in 10 cases without proteinuria (P less than 0.05). IgG-CIC were detected in 67% (12/18) with a mean level of 4.1 +/- 2.6 micrograms/ml, which was not significantly different from other glomerular diseases. No striking correlation was noted to exist between CIC levels at renal biopsy and the histological severity, because CIC are often present intermittently. C3d was quantitated by the rocket immunoelectrophoresis and C3 by the single radial immunodiffusion to determine the C3d/C3 ratio. The mean value of C3d/C3 was 0.63 +/- 0.19 which was significantly higher than a corresponding value for 15 healthy controls of 0.27 +/- 0.06 (P less than 0.05). Levels of IgA-CIC were found to have a significant positive correlation between C3d/C3 determined simultaneously in 33 cases (r = 0.43, P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMedDate not supplied

Bf S gene frequency in Nigerians with HIV infection.

Complement immunogenetic susceptibility to human immunodeficiency virus (HIV) infection was examined in 40 Nigerians with serological and/or clinical evidence of the infection. A mild increase in C4A null alleles (C4AQO) frequency was observed in the patient group compared to a group of healthy subjects (25 per cent vs 17 per cent) but overall the HIV infected and the reference groups did not differ significantly in the frequency of alleles of C4A or C4B. In contrast, properdin factor B (Bf) S gene frequency was significantly higher in the patients with HIV infection (p less than 0.025). There was a concomitant decrease in Bf F allele and gene frequencies (p less than 0.01, and p less than 0.05), respectively. Furthermore, blank Bf allotypes due to excessive complement consumption were detected in two asymptomatic patients. These findings suggest that Major Histocompatibility Complex (MHC) located complement genes may be important HIV infection. In particular Bf S gene or even C4AQO alleles may be permissive or influence outcome of infection with HIV.

Adult↗
PubMed1991

[The cellular-humoral immune factors of patients with cholelithiasis uncomplicated and complicated by an inflammatory process].

82 patients-10 p. with uncomplicated cholelithiasis, 8 p. with chronic calculous cholecystitis, 34 p. with choledocholithiasis with stenosing papillo-odditis--and 30 healthy controls were examined, with monoclonal antibodies of the firm "Becton-Dickinson". The following immunocompetent cellular clones and subclones were examined: CD3+, CD16+, CD4+, CD8+, CD19+ CD4/CD8, HLA-DR+, CD3+. The results were read with analyzer for fluorescently marked activated cell clones "FACS-TAR". The serum IgA, IgM, IgG, C3-C4 complement fractions and circulating immune complexes were also examined. The analysis of the results shows that in the complicated cases of cholelithiasis with an inflammatory process in the biliary ducts several humoral and cellular immune factors take part.

Adult↗
PubMed1990

[Molecular genetics of 21-hydroxylase deficiency in congenital adrenal hyperplasia].

21-hydroxylase gene analysis was performed on the genomic DNA from patients with congenital adrenal hyperplasia (CAH), their siblings, their parents as well as from a healthy individual serving as control. After digestion by the Taq I and Bgl II restriction enzymes, DNA was hybridized with specific nucleotidic probes: pC21a for the 21-hydroxylase genes, pAT-A for the C4 component Complement genes, closely linked to the 21-hydroxylase genes on the 6 chromosome. Likewise the pFB3B probe was used for the B factor gene located 80 kilobases upstream the 21-hydroxylase gene. From this molecular analysis on 11 families, we report here 4 investigations showing the most frequent genetic abnormalities we have encountered: gene deletions, gene conversions and point mutations. These data show that the molecular approach is a powerful tool for studying this endocrine disease at the clinical, genetic and fundamental point of view.

Adrenal Hyperplasia, Congenital↗
PubMed1991

Systemic lupus erythematosus in a black South African child. First documented case report.

Systemic lupus erythematosus (SLE) is poorly described among black children in Africa despite being more frequent among some black adult populations than their white counterparts. The first black South African child with SLE is documented. The patient was a 10-year-old girl who had fever, facial rash (with complement (C4) deposited at the dermo-epidermal junction of normal skin), weight loss, central nervous system involvement (depression, withdrawal, retinal exudates), renal involvement (glomerular filtration rate 54 ml/min/1.73 m2; membranous nephropathy with mild mesangial proliferation; World Health Organisation classification Vb), alopecia, lymphadenopathy, hepatomegaly, positive Coombs test, hypeocomplementaemia, anti-DNA antibodies and positive anti-nuclear factor.

Black People↗
PubMed1991

Prenatal diagnosis of congenital adrenal hyperplasia due to 21-hydroxylase deficiency with DNA analysis.

Six families at risk of having a child with 21-hydroxylase deficiency (21-OHD) requested prenatal diagnosis by DNA analysis. This was performed by Southern hybridization mainly using the endonuclease-probe combination of TaqI-21-hydroxylase (21-OHase) complementary DNA (cDNA). In three families, the probands were found to have deletion of a 3.7 kb fragment corresponding to the functional 21-OHase gene (21-OHase B gene). In the three fetuses tested, genomic DNA extracted from the chorionic villi had the 3.7 kb fragment and all were judged to be unaffected. In the other three families, DNA analysis was uninformative in the detection of 21-OHD and was also unable to determine carrier status with 21-OHase cDNA. In one of these three families, however, linkage analysis detected restriction fragment length polymorphism (RFLP) with cDNA for the fourth component of the complement (C4).

Adrenal Hyperplasia, Congenital↗
PubMed1991

[The role of precipitating serum antibodies in tuberculosis patients].

The content of serum alpha 1-proteinase inhibitors (alpha 1-PI), alpha 2-macroglobulins, transferrins, albumin, immunoglobulins A, M and G and C3- and C4-complement factors was investigated in a group of patients (n = 35) with pulmonary tuberculosis who showed precipitating antituberculous circulating antibodies having the properties of autoantibodies. A direct relationship between the available circulating antibodies cross-reacting with the tissues and the rate of an extrapulmonary localization of tuberculous process in pulmonary tuberculosis patients, on the one hand, and their inverse relationship to the level of blood alpha 1-PI, on the other, were revealed. It is recommended to define cross-reacting antibodies and alpha 1-PI concentration to predict the risk of extrapulmonary foci of a tuberculous inflammation.

Antibodies, Bacterial↗
PubMed1991

Interleukin-6 and its relation to the humoral immune response and clinical parameters in burned patients.

The cytokine interleukin-6, which has been shown to be increased in patients with burn injuries, is produced by activated monocytes and endothelial cells and has many in vitro activities, including stimulation of acute-phase protein synthesis in hepatocytes, immunoglobulin synthesis in B lymphocytes, and stimulation of growth of megakaryocytes. In 13 patients with a mean of 31% full-thickness burns, we studied the relation of serum interleukin-6 to clinical parameters and parameters of the acute-phase response and immunoglobulin production. Interleukin-6 was already elevated within hours after the injury was sustained, and it remained elevated for several weeks. All components of the acute-phase response were observed: fever, tachycardia, leukocytosis with an associated left shift, elevation of C-reactive protein and alpha 1-antitrypsin, and a decrease in albumin levels. In the second week after burn injury, immunoglobulin M levels peaked, followed by a prolonged elevation of immunoglobulin G levels. Thrombocyte counts initially decreased and rebounded to supranormal levels after 2 weeks. Interleukin-6 levels were positively correlated with acute-phase responses. We believe that the production of interleukin-6 induces the synthesis of acute-phase proteins. High interleukin-6 levels may also be an etiologic factor in the marked immunoglobulin response observed. Likewise, the relation between the megakaryocyte-promoting activity of interleukin-6 and the rebound thrombocytosis requires further investigation.

Adult↗