Incidence of cervical human papillomavirus infection in systemic lupus erythematosus women.

Objectives Our objective was to study the incidence, persistence and clearance of human papillomavirus infection in systemic lupus erythematosus women and assess risk factors for persistence of human papillomavirus infection. Methods We carried out a prospective, observational cohort study of 127 systemic lupus erythematosus women. Patients were evaluated at baseline and at three years. Traditional and systemic lupus erythematosus women-related disease risk factors were collected. Gynaecological evaluations and cervical cytology screening were made. Human papillomavirus detection and genotyping were made by polymerase chain reaction and linear array. Results The cumulative prevalence of human papillomavirus infection increased from 22.8% at baseline to 33.8% at three years; p = < 0.001: 20.1% of patients experienced 43 incident infections. The risk of any human papillomavirus infection was 10.1 per 1000 patient-months. At three years, 47 (88.6%) prevalent infections were cleared. Independent risk factors associated with incident human papillomavirus infection included more lifetime sexual partners (odds ratio = 1.8, 95% confidence interval = 1.11-3.0) and cumulative cyclophosphamide dose (odds ratio = 3.9, 95% confidence interval = 1.2-12.8). Conclusions In systemic lupus erythematosus women, the cumulative prevalence of human papillomavirus infection, including high risk-human papillomavirus and multiple human papillomavirus infections, may increase over time. Most persistent infections were low risk-human papillomavirus. The number of lifetime sexual partners and the cumulative cyclophosphamide dose were independently associated with incident human papillomavirus infection.

Lack of association between serum 25-hydroxyvitamin D levels and cervical human papillomavirus infection in systemic lupus erythematosus.

Our objective was to evaluate whether vitamin D deficiency is associated with cervical human papilloma virus (HPV) infection in women with SLE. This is a cross-sectional study of 67 women with SLE. A structured questionnaire was administered to ascertain the possible risk factors associated with cervical HPV infection. A gynaecological evaluation and cervical cytology screening were made. HPV detection and genotyping was made by PCR and linear array assay. Serum 25 hydroxyvitamin D levels were quantified by chemiluminescence immunoassay. Mean age and disease duration were 44.8 ± 10.6 and 42.5 ± 11.8 years, respectively. Demographic characteristics were similar in patients with and without deficiency (<20 ng/ml and ≥20 ng/ml). There were 28.4% of women with cervical HPV infection and 68.4% had high-risk HPV infections. Patients with 25 hydroxyvitamin D levels <20 ng/ml had a higher prevalence of cervical HPV infection than those with levels ≥20 ng/ml (30.7% vs. 25.8%; p = 0.72). We found no significant difference when high-risk HPV infection was evaluated (36.8% vs. 31.5%; p = 0.73). In conclusion, women with SLE have a high prevalence of vitamin D deficiency and cervical HPV infection. However, we found no association between vitamin D deficiency and cervical HPV.

Delineation of the minimal catalytic domain of human Galbeta1-3GalNAc alpha2,3-sialyltransferase (hST3Gal I).

The CMP-Neu5Ac:Galbeta1-3GalNAc alpha2,3-sialyltransferase (ST3Gal I, EC 2.4.99.4) is a Golgi membrane-bound type II glycoprotein that catalyses the transfer of sialic acid residues to Galbeta1-3GalNAc disaccharide structures found on O-glycans and glycolipids. In order to gain further insight into the structure/function of this sialyltransferase, we studied protein expression, N-glycan processing and enzymatic activity upon transient expression in the COS-7 cell line of various constructs deleted in the N-terminal portion of the protein sequence. The expressed soluble polypeptides were detected within the cell and in the cell culture media using a specific hST3Gal I monoclonal antibody. The soluble forms of the protein consisting of amino acids 26-340 (hST3-Delta25) and 57-340 (hST3-Delta56) were efficiently secreted and active. In contrast, further deletion of the N-terminal region leading to hST3-Delta76 and hST3-Delta105 gave also rise to various polypeptides that were not active within the transfected cells and not secreted in the cell culture media. The kinetic parameters of the active secreted forms were determined and shown to be in close agreement with those of the recombinant enzyme already described (H. Kitagawa, J.C. Paulson, J. Biol. Chem. 269 (1994)). In addition, the present study demonstrates that the recombinant hST3Gal I polypeptides transiently expressed in COS-7 cells are glycosylated with complex and high mannose type glycans on each of the five potential N-glycosylation sites.

The human sialyltransferase family.

The human genome encodes probably more than 20 different sialyltransferases involved in the biosynthesis of sialylated glycoproteins and glycolipids but to date only 15 different human sialyltransferase cDNAs have been cloned and characterized. Each of the sialyltransferase genes is differentially expressed in a tissue-, cell type-, and stage-specific manner to regulate the sialylation pattern of cells. These enzymes differ in their substrate specificity, tissue distribution and various biochemical parameters. However, enzymatic analysis conducted in vitro with recombinant enzyme revealed that one linkage can be synthesized by multiple enzymes. We present here an overview of these human genes and enzymes, the regulation of their occurrence and their involvement in several physiological and pathological processes.

Cloning, expression and gene organization of a human Neu5Ac alpha 2-3Gal beta 1-3GalNAc alpha 2,6-sialyltransferase: hST6GalNAcIV.

On the basis of the detection of expressed sequence tag ('EST') similar to the rat N-acetylgalactosamine alpha2,6-sialyltransferase (ST6GalNAc) III cDNA, we have identified a novel member of the human ST6GalNAc family. We have isolated a cDNA clone containing an open reading frame that codes for a type II membrane protein of 302 amino acids with a seven-amino-acid cytoplasmic domain, an 18-amino-acid transmembrane domain and the smallest described catalytic domain of 277 amino acids. This predicted sialyltransferase sequence is similar to the rat ST6GalNAc III (46.6%), but was found to be even more similar to the recently reported mouse ST6GalNAc IV (88.1%) on the basis of amino acid sequence identity. Northern-blot analysis showed that the newly identified gene is expressed constitutively in various adult human tissues as a 2.2kb transcript, but was also found to be expressed at lower levels in brain, heart and skeletal muscle as a 2.5kb transcript. Expression of the hST6GalNAc IV gene was investigated by reverse transcription PCR in various human cancer cells, and was found to be present in the majority of cell types with the exception of the carcinoma cell line T47D and pro-monocyte THP cells. The transient expression in COS-7 cells of the full-length cDNA led to the production of an active enzyme sharing the acceptor specificity of the ST6GalNAc family towards Neu5Ac alpha 2-3Gal beta 1-3GalNAc alpha-O-R (where 'R' denotes H, benzyl, or a peptidic chain). Detailed analysis in vitro of substrate specificity revealed that the enzyme required the trisaccharide Neu5Ac alpha 2-3Gal beta1-3GalNAc found on O-glycans and arylglycosides. In addition, we have clarified the genomic organization of ST6GalNAc IV gene.