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1.
Mycopathologia ; 182(5-6): 487-493, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28101694

ABSTRACT

According to epidemiological, clinical and mycological criteria, it has long been admitted that the Trichophyton mentagrophytes species includes two varieties: a zoophilic variety (var. mentagrophytes) and an anthropophilic variety (var. interdigitale) that involve the upper and the lower part of the body, respectively. The further application of molecular techniques to the characterization of dermatophyte strains showed that this classification is unreliable. The aim of our study was to assess the usefulness of PCR-RFLP (restriction fragment length polymorphism) and sequencing in the characterization of T. mentagrophytes strains taken from Tunisian patients. The study was carried out in 2008 in the laboratory of Parasitology-Mycology of Farhat Hached University Hospital, Sousse, Tunisia. A total of 133 strains were isolated from 133 patients addressed to the laboratory for dermatological lesions very evocative of dermatomycosis. Eighty strains were isolated from lesions located on the lower part of the body (onychomycosis, tinea pedis) and 53 strains from the upper part of the body (tinea capitis, tinea corporis). All strains were submitted to mycological examination (direct microscopic examination and culture on Sabouraud medium) and further investigated by using RFLP analysis of the PCR-amplified ITS1-5.8 s-ITS2 region of the ribosomal DNA and the MvaI restriction enzyme. In addition, 62 strains were further submitted to a sequencing of the ITS1-5.8 s-ITS2 region. On the basis of mycological criteria, all strains were diagnosed as T. mentagrophytes. All strains produced the same RFLP pattern and were identified as T. mentagrophytes interdigitale regardless of the location of lesions. Out of the 62 sequenced strains, 16 were found anthropophilic and 46 were zoophilic. In conclusion, all strains provisionally diagnosed as T. mentagrophytes on the basis of mycological criteria were shown to belong to T. interdigitale by using PCR-RFLP and sequencing irrespective of the site of lesions. The predominance of zoophilic strains needs further investigation.


Subject(s)
Molecular Typing , Mycological Typing Techniques , Tinea/microbiology , Trichophyton/classification , Trichophyton/isolation & purification , DNA, Fungal/chemistry , DNA, Fungal/genetics , DNA, Ribosomal Spacer/chemistry , DNA, Ribosomal Spacer/genetics , Genotype , Humans , Phenotype , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length , Sequence Analysis, DNA , Trichophyton/genetics , Trichophyton/physiology , Tunisia
2.
Mycoses ; 57(1): 19-26, 2014 Jan.
Article in English | MEDLINE | ID: mdl-23734576

ABSTRACT

Onychomycosis is one of the most prevalent dermatophytic diseases. Mycological methods used in the conventional diagnosis may not be optimal. Multiplex (MX) PCR was reported as a reliable alternative. Dermatophyte gene sequence records were used to design a MX PCR for detection and identification of dermatophytes in nail specimens. A MX PCR method based on the amplification of the chitin synthase 1 and internal transcribed spacer genes was developed. The study included 93 strains of dermatophytes and non-dermatophytic fungi, six dermatophytic reference strains and 201 nail specimens from patients with dermatophytic onyxis. DNA extraction directly from nail samples was carried out by using the QIAamp DNA extraction kit (Quiagen). A set of primers was designed and their specificity was assessed. MX PCR detected the causal agent in specimens from which Trichophyton rubrum and T. interdigitale grew in culture and also identified a dermatophyte species in an additional 32 specimens that were negative in microscopy and culture. None of the investigated non-dermatophytic strains was positive. Sensitivity of MX PCR was higher as compared to mycological examination (97% vs. 81.1%). MX PCR for direct detection of dermatophytes from nail samples yielded mixed flora in 32.8% of samples. MX PCR proved sensitive and adequate for the diagnosis of dermatophytic onychomycosis. It is much adapted to cases where culture is negative or contaminated by overgrowing moulds, which makes the identification of the causal agent problematic.


Subject(s)
Arthrodermataceae/isolation & purification , Dermatomycoses/microbiology , Multiplex Polymerase Chain Reaction/methods , Mycological Typing Techniques/methods , Nail Diseases/microbiology , Arthrodermataceae/classification , Arthrodermataceae/genetics , DNA Primers/genetics , DNA, Fungal/genetics , Dermatomycoses/diagnosis , Female , Humans , Nail Diseases/diagnosis , Nails/microbiology , Sensitivity and Specificity
3.
Pathol Biol (Paris) ; 61(3): 113-6, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23399411

ABSTRACT

OBJECTIVES: The presence of a wide variety of autoantibodies is a characteristic feature of systemic lupus erythematosus (SLE). Although non-specific, anti-complement C1q (anti-C1q) were shown to correlate with the occurrence of active nephritis. The present study aimed to investigate the prevalence of anti-C1q in Tunisian SLE patients and their association with clinical manifestations, especially renal involvement. PATIENTS AND METHODS: IgG anti-C1q antibodies were assessed by Elisa in 98 SLE patients, 55 patients with rheumatoid arthritis (RA) and 65 healthy individuals (HI). RESULTS: Anti-C1q were found in 53 (54.1%) patients with SLE, three (5%) patients with RA and six (9.3%) HI. Among the 65 patients with renal involvement, anti-C1q were present in 35 (53.8%) patients. There was no significant association between anti-C1q and renal or extrarenal manifestations. In addition, there was no correlation between anti-C1q titer and SLEDAI index. Anti-C1q were significantly associated with anti-nucleosome (P=0.001), anti-Sm (P=0.01) and a low C4 level (P=0.046). Concomitant presence of anti-C1q and anti-dsDNA antibodies was not associated with renal manifestations. CONCLUSION: Our study shows that prevalence of anti-C1q was comparable with that previously reported in Caucasian populations. These antibodies were associated with a low C4 level. However, there was no association between anti-C1q and renal involvement or severity of nephritis.


Subject(s)
Autoantibodies/blood , Complement C1q/immunology , Lupus Erythematosus, Systemic/epidemiology , Adolescent , Adult , Aged , Autoantibodies/analysis , Child , Child, Preschool , Female , Humans , Lupus Erythematosus, Systemic/blood , Lupus Erythematosus, Systemic/immunology , Male , Middle Aged , Population , Retrospective Studies , Seroepidemiologic Studies , Tunisia/epidemiology , Young Adult
4.
J Mycol Med ; 22(3): 249-55, 2012 Sep.
Article in English | MEDLINE | ID: mdl-23518083

ABSTRACT

BACKGROUND: Onychomycosis is one of the most prevalent dermatophytic diseases. Mycological methods used in the conventional diagnosis may not be optimal. PCR was reported as a reliable alternative in the diagnosis of dermatophytosis. MATERIALS AND METHODS: A PCR method based on the amplification of the chitin synthase 1 gene was developed. The study included 119 strains of dermatophytes and non dermatophytic fungi, eight dermatophytic reference strains and 201 nail specimens from patients with dermatophytic onyxis. DNA extraction was carried out by using the QIAamp DNA extraction kit (Quiagen). RESULTS: PCR positivity was based on the production of a specific 432 bp fragment. None of the investigated non dermatophytic strains was positive. Sensitivity of PCR was higher as compared to mycological examination (90.5% vs. 81.1%). PCR was positive in 31 onyxis cases with positive direct examination but negative or contaminated culture. In contrast, PCR was negative in 10 cases where both direct examination and culture were found positive. CONCLUSION: PCR is an adequate tool for the diagnosis of dermatophytic onychomycosis. It is much adapted to cases where culture is negative or contaminated by overgrowing molds, which makes the identification of the causal agent problematic.


Subject(s)
Arthrodermataceae/isolation & purification , Chitin Synthase/genetics , DNA, Fungal/genetics , Fungal Proteins/genetics , Genes, Fungal , Mycology/methods , Onychomycosis/diagnosis , Polymerase Chain Reaction/methods , Arthrodermataceae/enzymology , Arthrodermataceae/genetics , DNA, Fungal/isolation & purification , Humans , Onychomycosis/microbiology , Sensitivity and Specificity , Species Specificity , Trichophyton/enzymology , Trichophyton/genetics , Trichophyton/isolation & purification
5.
East Mediterr Health J ; 16(6): 630-5, 2010 Jun.
Article in French | MEDLINE | ID: mdl-20799590

ABSTRACT

We assessed the knowledge attitudes and practices of primiparous women with regard to exclusive breastfeeding and the use of formula milk. A total of 260 women were interviewed and the results showed that 41.5% of the women breastfed exclusively while 58.5% bottle-fed only or did so together with breastfeeding. Of those who breastfed, 43.0% did not do so soon after giving birth and did not know about colostrum. Overall, the knowledge, attitudes and practices of the mothers were unsatisfactory concerning the golden rules for successful breastfeeding, the ideal duration of exclusive breastfeeding and the food to include when introducing complementary feeding. This might be due to a low level of schooling and information, hence the need for improving strategies for maternal care during the antenatal and postnatal periods.


Subject(s)
Attitude to Health , Bottle Feeding , Breast Feeding , Health Knowledge, Attitudes, Practice , Mothers , Parity , Adult , Bottle Feeding/psychology , Bottle Feeding/statistics & numerical data , Breast Feeding/psychology , Breast Feeding/statistics & numerical data , Educational Measurement , Educational Status , Female , Health Services Needs and Demand , Humans , Mothers/education , Mothers/psychology , Mothers/statistics & numerical data , Motivation , Patient Education as Topic , Pregnancy , Surveys and Questionnaires , Time Factors , Tunisia , Weaning
6.
(East. Mediterr. health j).
in French | WHO IRIS | ID: who-117930

ABSTRACT

We assessed the knowledge attitudes and practices of primiparous women with regard to exclusive breastfeeding and the use of formula milk. A total of 260 women were interviewed and the results showed that 41.5% of the women breastfed exclusively while 58.5% bottle-fed only or did so together with breastfeeding. Of those who breastfed, 43.0% did not do so soon after giving birth and did not know about colostrum. Overall, the knowledge, attitudes and practices of the mothers were unsatisfactory concerning the golden rules for successful breastfeeding, the ideal duration of exclusive breastfeeding and the food to include when introducing complementary feeding. This might be due to a low level of schooling and information, hence the need for improving strategies for maternal care during the antenatal and postnatal periods


Subject(s)
Health Knowledge, Attitudes, Practice , Mothers , Bottle Feeding , Educational Status , Breast Feeding
7.
East Mediterr Health J ; 15(6): 1483-8, 2009.
Article in English | MEDLINE | ID: mdl-20218141

ABSTRACT

This study determined the prevalence of inherited factor V Leiden mutation in a group of 128 thrombosis patients (102 with venous thrombosis and 26 with arterial thrombosis) attending a hospital in Sousse, Tunisia, and a control group of 100 with no history of thrombosis. Using an allele-specific PCR amplification technique, factor V Leiden was found in significantly more patients (20.3%) than controls (6.0%). The higher prevalence was significant in the subgroup of venous thrombosis patients but not in arterial thrombosis patients. The allele frequency was 3.5% in the normal Tunisian population. Screening Tunisian patients with venous thrombosis and their relatives for factor V Leiden may be justified.


Subject(s)
Factor V/genetics , Genetic Predisposition to Disease , Thrombosis , Adolescent , Adult , Aged , Case-Control Studies , Chi-Square Distribution , Child , Child, Preschool , Gene Frequency/genetics , Genetic Predisposition to Disease/epidemiology , Genetic Predisposition to Disease/genetics , Genetic Testing , Humans , Infant , Inpatients/statistics & numerical data , Middle Aged , Pedigree , Polymerase Chain Reaction , Prevalence , Risk Factors , Thrombosis/epidemiology , Thrombosis/genetics , Tunisia/epidemiology
8.
(East. Mediterr. health j).
in English | WHO IRIS | ID: who-117788

ABSTRACT

This study determined the prevalence of inherited factor V Leiden mutation in a group of 128 thrombosis patients [102 with venous thrombosis and 26 with arterial thrombosis] attending a hospital in Sousse, Tunisia, and a control group of 100 with no history of thrombosis. Using an allele-specific PCR amplification technique, factor V Leiden was found in significantly more patients [20.3%] than controls [6.0%]. The higher prevalence was significant in the subgroup of venous thrombosis patients but not in arterial thrombosis patients. The allele frequency was 3.5% in the normal Tunisian population. Screening Tunisian patients with venous thrombosis and their relatives for factor V Leiden may be justified


Subject(s)
Mutation , Thrombosis , Prevalence , Polymerase Chain Reaction , Factor V
10.
East Mediterr Health J ; 11(1-2): 102-8, 2005.
Article in English | MEDLINE | ID: mdl-16532678

ABSTRACT

Factor VII gene polymorphisms may contribute to elevations in factor VII coagulant (FVIIc) levels that have been associated with cardiovascular risk. We therefore studied the association of two polymorphisms--R353Q polymorphism at codon 353 involving the catalytic region and the 10 base pair (bp) insertion polymorphism involving the promoter region--with FVllc levels in 176 healthy Tunisians. The variant Q allele had a frequency of 0.213 (SD 0.021) whereas the frequency of the 10 bp insert allele was 0.250 (SD 0.023). Subjects with R/R genotype had significantly higher FVllc levels than Q353 heterozygote and homozygote subjects (96.36 versus 59.52). FVIIc levels with the 10 bp insertion polymorphism were not significantly different. The Q353 allele of the factor VII gene polymorphism is associated with decreased factor VII and could be protective against cardiovascular disease.


Subject(s)
Factor VII/genetics , Factor VII/metabolism , Gene Frequency/genetics , Polymorphism, Genetic/genetics , Adolescent , Adult , Base Pairing/genetics , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/genetics , Chi-Square Distribution , Codon/genetics , Female , Genetic Testing , Genetic Variation/genetics , Genotype , Humans , Male , Middle Aged , Mutagenesis, Insertional/genetics , Phenotype , Population Surveillance , Prevalence , Promoter Regions, Genetic/genetics , Risk Factors , Tunisia/epidemiology
11.
(East. Mediterr. health j).
in English | WHO IRIS | ID: who-116925

ABSTRACT

Factor VII gene polymorphisms may contribute to elevations in factor VII coagulant [FVIIc] levels that have been associated with cardiovascular risk. We therefore studied the association of two polymorphisms--R353Q polymorphism at codon 353 involving the catalytic region and the 10 base pair [bp] insertion polymorphism involving the promoter region--with FVllc levels in 176 healthy Tunisians. The variant Q allele had a frequency of 0.213 [SD 0.021] whereas the frequency of the 10 bp insert allele was 0.250 [SD 0.023]. Subjects with R/R genotype had significantly higher FVllc levels than Q353 heterozygote and homozygote subjects [96.36 versus 59.52]. FVIIc levels with the 10 bp insertion polymorphism were not significantly different. The Q353 allele of the factor VII gene polymorphism is associated with decreased factor VII and could be protective against cardiovascular disease


Subject(s)
Base Pairing , Cardiovascular Diseases , Chi-Square Distribution , Codon , Gene Frequency , Factor VII
12.
Ann Biol Clin (Paris) ; 62(2): 217-21, 2004.
Article in French | MEDLINE | ID: mdl-15047475

ABSTRACT

Antiphospholipid antibodies are associated with arterial and venous thrombosis and recurrent abortions. However, the prevalence of these antibodies in repeated miscarriages varies in different reports. To obtain quantitative data with restricted criteria and discuss the origin of the variability on the literature, we investigated the presence of antiphospholipid antibodies in 146 women who had 2 or more consecutive pregnancy losses and in 99 women whose pregnancies were successful. Antiphospholipid antibodies (lupus anti-coagulant or anticardiolipin antibodies of 20 or more IgG units) were found in 45% of women with pregnancy losses and in 9% of controls (p < 0.001). The type of loss was determined according to the trimester of pregnancy and the time of the fetal loss. 68% of patients with antiphospholipid antibodies had at least one fetal loss on the second or third trimester compared with 45% of patients without fetal loss (p < 0.01). Further studies should be conducted using more rigorous definition of clinical and laboratory characteristics in a way to allow better comparison between studies.


Subject(s)
Abortion, Habitual/blood , Antibodies, Antiphospholipid/blood , Abortion, Habitual/epidemiology , Adolescent , Adult , Female , Humans , Pregnancy , Retrospective Studies
15.
Encephale ; 27(4): 373-6, 2001.
Article in French | MEDLINE | ID: mdl-11686060

ABSTRACT

UNLABELLED: It is recommended to reduce by one half the dosages of tricyclic antidepressants for patients over 65 years of age, in order to avert the occurrence of side-effects. The question we studied was: is it rightful to prescribe tricyclic antidepressants at half-dose to hospitalized elderly people? It is important, for the following reasons, to specify the rules of prescription of tricyclics in elderly patients: 1) The elderly population is on the increase; 2) There is a high prevalence of depression in elderly patients; 3) Depression exposes the elderly person to an increased risk of suicide; 4) Depression influences the prognosis of associated organic disorders 5) Recourse to tricyclic antidepressants is often necessary within this population group because of treatment resistant forms of depression which impose the use of different families of antidepressants and thus resort to tricyclics despite their lower tolerance. OBJECTIVES AND METHODS: The aim of our study is to evaluate whether the half doses of tricyclics recommended for an elderly person are sufficient in the case of an hospitalized patient. In order to provide some answer to this question, we have carried out a retrospective study. We have studied a sample of patients over-65, hospitalized at the Clinique des Maladies Mentales et de l'Encéphale, over a period of two years, with a ICD 10 diagnosis of moderate or severe intensity major depressive episode, and treated effectively with return to the euthymia. Creatinemia was prescribed systematically to each patient on entry. Only patients with normal renal function were retained. Laboratory norms are between 45 and 120 micromol/liter. The routine practice of imipraminic blood dosages allowed the comparison of blood levels obtained among patients treated with posologies inferior or equal to 75 mg/day imipraminic, to those treated with more than 75 mg/day imipraminic for a least a week. The percentage observed were compared using the Khi2 test with Yates correction. We retained the blood concentrations of the mother molecule for tertiary amines (imipramine, clomipramine and amitriptyline). The samples were taken after at least seven days of treatment at the same dose, and twelve to thirteen hours after the last taking. The maxima of blood levels were respectively: desipramine 200 ng/ml, clomipramine 258 ng/ml, imipramine 163 ng/ml, amitriptyline 129 ng/ml. Research for evidence in favor of toxicity (fall, delirium, convulsion, reduction of dosage before discharge), was done through revision of patients' clinical files. RESULTS: The test group consisted of 87 individuals. The average age was 71.3 years (SD: 5.09). Mean creatinemia was 83.73 mmol/l (SD: 26.89). The population thus selected divided into 4 groups: 61 (70.1%) were given imipraminics, 10 (11.5%) serotonin recapture inhibitors, 11 (12.7%) other antidepressants essentially of mianserine and 5 (5.7%) treatment by electroconvulsivotherapy. The imipraminics prescribed were desipramine, imipramine, clomipramine and amitriptyline. Among the 61 patients treated with imipramine, blood level dosage was practised on 48 patients (79%). Two subgroup were distinguished: 13 (21%) received dosages inferior ou equal to 75 mg/day and 48 (79%) superior to 75 mg/day. The mean dosage found in the sub-group of patients treated with dosages superior to 75 mg/day was 140 mg/day (SD: 30). The subgroup treated with dosages superior to 75 mg/day was more frequently monitored than the subgroup receiving dosages inferior or equal to 75 mg/day, respectively 40/48 (83%), and 8/13 (62%). This difference is statistically nonsignificant (p > 0.10). The analysis of dosages used showed that:--among the dosages effected upon patients receiving doses inferior or equal to 75 mg/day, 1 (12.5%) exceeded the maximal value of therapeutic range.--Among the dosages effected upon patients receiving dosages superior to 75 mg/day, 9 (22%) exceeded the maximal value of the therapeutic range. The difference is statistically significant (p < 0.001). On revision of clinical files, no patient presented any element that might lead one to suspect toxicity such as defined in "Objectives and Methods". CONCLUSION: In our study, patients were hospitalized and so benefited from closer observation than one can expect in outpatients. In this particular context, the dosages used are close to those advocated for the general population. With the elderly subject, the systematic prescription of half-dose tricyclics runs the risk of infratherapeutic dosage. It is thus preferable to resort to blood level dosage and to look for a maximum dose tolerance before concluding ineffectuality. This allows one to monitor whether the blood levels obtained are included in the therapeutic range; to avoid toxic doses and to check weak compliance in the elderly patient. Our findings do not oppose the use, for the elderly hospitalized depressive, of doses of imipraminics close to those of a young subject. To confirm these results it would be desirable to carry out o prospective study, including a systematised evaluation of adverse effects and a comparison of clinical effectiveness for parallel groups of elderly patients receiving different doses of imipraminic antidepressants.


Subject(s)
Antidepressive Agents, Tricyclic/therapeutic use , Depressive Disorder, Major/drug therapy , Depressive Disorder, Major/epidemiology , Aged , Antidepressive Agents, Tricyclic/administration & dosage , Antidepressive Agents, Tricyclic/blood , Depressive Disorder, Major/diagnosis , Female , Humans , Male , Psychiatric Status Rating Scales , Retrospective Studies
16.
Mol Psychiatry ; 6(4): 434-9, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11443529

ABSTRACT

The promoter polymorphism of the serotonin transporter gene (HTT, locus SLC6A4) is of special interest in autism given the well-replicated platelet hyperserotonemia of autism, treatment effects of serotonin reuptake inhibitors, and the role of serotonin in limbic functioning and neurodevelopment. Parent-offspring transmission of the long (l) and short (s) alleles of the deletion/insertion polymorphism in the HTT promoter region was examined in families of 71 children with autism using the transmission test for linkage disequilibrium (TDT). Transmission of HTT promoter alleles did not differ between probands with autism and their unaffected siblings. However, allelic transmission in probands was dependent upon severity of impairments in the social and communication domains, with greater s allele transmission in severely impaired individuals and greater l transmission in mild/moderately impaired individuals. This relationship between HTT promoter alleles and severity of autistic impairment was also seen when ratings of social and communication behaviors were compared across genotypes. The data indicate that HTT promoter alleles by themselves do not convey risk for autism, but, rather, modify the severity of autistic behaviors in the social and communication domains. The results require replication and, given the size of the groups and subgroups examined, must be considered still preliminary. The results suggest that future research on the genetics of autism should carefully assess each of the major behavioral domains and seriously consider the possible role of modifying loci.


Subject(s)
Autistic Disorder/genetics , Carrier Proteins/genetics , Membrane Glycoproteins/genetics , Membrane Transport Proteins , Nerve Tissue Proteins , Polymorphism, Genetic , Promoter Regions, Genetic , Adolescent , Adult , Autistic Disorder/psychology , Child , Child, Preschool , Chromosome Mapping , DNA Transposable Elements , Fathers , Female , France , Genetic Carrier Screening , Genetic Predisposition to Disease , Genotype , Humans , Male , Mothers , Nuclear Family , Sequence Deletion , Serotonin Plasma Membrane Transport Proteins , Wechsler Scales , White People/genetics
17.
Tunis Med ; 79(10): 508-14, 2001 Oct.
Article in French | MEDLINE | ID: mdl-11910690

ABSTRACT

To know nature and the dimension of the change of the customs of life leads by the Ramadan, we led a comparative descriptive inquiry before and during the month of the fast at 84 adults residents in the district of Tunis. Our results underline an increase of the consumption of meat and eggs with an average frequency of 4.3 and 6.1 times a week respectively. This overconsumption of the animal proteins contrasts with a tendency in the decline of the consumptions of vegetables. The exciting (tea, coffee, tobacco) are less consumed during the Ramadan. Also, we noted a decline of 50% of the average number of smoked cigarettes. There is an intensification of domestic links with an increase of the frequency of exchange of domestic visits. It's crossed of average from 0.7 to 1.2 times a week (p < 0.001). The phenomenon of irritability is frequently lived by near 20% of the investigated. We recommend under shape of an educational program the intensification of positive customs and the correction of negative customs, to benefit of sacred month, to tighten towards a more balanced life all year.


Subject(s)
Activities of Daily Living , Diet , Islam , Life Style , Adult , Cultural Characteristics , Female , Humans , Interpersonal Relations , Male , Middle Aged , Tunisia
19.
Autoimmunity ; 12(1): 61-8, 1992.
Article in English | MEDLINE | ID: mdl-1617106

ABSTRACT

This study shows that purified murine monoclonal anti-DNA antibodies and human polyclonal anti-DNA antibodies (from systemic lupus erythematosus--SLE--patients), preincubated with DNA, acquire anti-histone reactivity. Conversely, DNAse I treatment of SLE patients' antibodies with anti-histone activity abolishes such activity. It has previously been demonstrated that anti-DNA antibodies bind to the cell membrane and recognize cell-surface polypeptides that have been identified with histones by partial sequencing. In a series of 33 sera from patients with clinically active disease and 29 sera from patients in clinical remission, positivity of an immunoblot analysis detecting antibodies against these polypeptides was associated with clinical activity of SLE (sensitivity, 0.88; specificity, 0.90). Anti-histone reactivity detected by ELISA appeared to be also a good marker of SLE activity (sensitivity, 0.64; specificity, 0.54). As expected, anti-native DNA antibody positivity and lowered complement dosage were also associated with clinical activity (sensitivity, 0.79 and 0.63, respectively; specificity, 0.48 and 0.93, respectively). Since anti-histone reactivity reflects, at least partly, the presence of anti-DNA antibodies complexed to DNA, which could bind to cell-membrane determinants, and is associated with disease clinical activity, it is suggested that this mechanism can contribute to explain the pathogenicity of anti-DNA antibodies.


Subject(s)
Antibodies, Antinuclear/immunology , Antigen-Antibody Complex/analysis , DNA/immunology , Histones/immunology , Lupus Erythematosus, Systemic/immunology , Adult , Female , Humans , Lupus Coagulation Inhibitor/analysis , Male
20.
Proc Natl Acad Sci U S A ; 86(12): 4669-73, 1989 Jun.
Article in English | MEDLINE | ID: mdl-2660143

ABSTRACT

A crude supernatant of hybridoma secreting a monoclonal anti-double-stranded (ds)DNA antibody (PME77 mAb), used to stain fibroblasts (CVI cells) in immunofluorescence, gives a punctuated staining of variable intensity. We had suggested that anti-DNA antibodies bind to cell-surface protein(s) of several cells. When the mAb of this crude supernatant was purified on a dsDNA-cellulose column and a histone-Trisacryl column, the mAb no longer bound to the cell surface. Only when dsDNA plus purified histones was added to the purified antibody did the immune complex strongly and uniformly stain again the cell surface of CVI cells. No significant staining was observed if either DNA or histones were omitted. A signal 94-kDa protein from membrane fractions of CVI, Raji, and RINm cell lines was visualized in immunoblots when mAb-DNA-histone complexes were applied to the nitrocellulose strips. No polypeptide was seen if one component was omitted. This 94-kDa protein behaved like a plasma membrane protein since it required the use of detergent to be solubilized and was quantitatively recovered in the Triton X-114 detergent-rich phase. Moreover, a brief treatment of living cells with trypsin cleared off this protein. Purified nucleosomes could be substituted to DNA-histone complexes, giving rise to identical results. Finally, purified polyclonal anti-DNA antibodies from sera of systemic lupus erythematosus patients labeled a 94-kDa protein provided that DNA-histone complexes were added. Anti-DNA autoantibodies could be pathogenic when they are bound to nucleosomes.


Subject(s)
Antibodies, Monoclonal/immunology , Autoantibodies/immunology , DNA/immunology , Histones/metabolism , Membrane Proteins/immunology , Nucleosomes/immunology , Animals , Antigen-Antibody Complex/analysis , Cell Line , DNA/metabolism , Fluorescent Antibody Technique , Histones/immunology , Molecular Weight , Nucleosomes/metabolism
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