Giovanna Sersale

Bio: Giovanna Sersale is an academic researcher from University of Milan. The author has contributed to research in topics: Cationic liposome & Reporter gene. The author has an hindex of 7, co-authored 11 publications receiving 385 citations.

Comparison between cationic polymers and lipids in mediating systemic gene delivery to the lungs.

Abstract: Comparison between cationic polymers and lipids in mediating systemic gene delivery to the lungs

The natural course and the impact of therapies of cardiac involvement in the mucopolysaccharidoses.

Abstract: Objective To analyze cardiac involvement and its progression in mucopolysaccharidoses, and to assess the short term impact of new therapeutic strategies. Patients and methods We studied echocardiographically 57 patients with various types of mucopolysaccharidoses, specifically types I, II, III, IV and VI, with a median age at the diagnosis of cardiac involvement of 5 years, following them for a median of 4.6 years, with a range from 0.9 to 21.2 years. We used a scoring system, along with the so-called delta score, to quantify the severity of involvement at baseline and at last examination, and to chart their progression over time. Results Cases with cardiac involvement increased from 59.6% to 87.3% at the last examination. The scores increased with age, and were significantly different according to the specific type of mucopolysaccharidosis. Involvement of the mitral valve was most common, often associated with an aortic valvar anomaly and/or left ventricular hypertrophy. Patients with the first and second types had more severe involvement than those with the third or fourth types. Patients undergoing transplantation of haematopoietic stem cells seem to stabilize after an initial worsening while, in contrast, we were unable to demonstrate an effect of enzyme replacement therapy on the progression of the cardiac disease, possibly because those receiving such treatment had a higher median age, more severe cardiac disease and shorter follow-up. Conclusions Cardiac involvement was present early in more than a half of the patients identified as having mucopolysaccharidosis, and generally progressed, being more frequent and severe in the first and second types of the disease. Longer follow-up is needed to demonstrate any significant improvement induced by new therapies.

Acute pyelonephritis as a cause of hyponatremia/hyperkalemia in young infants with urinary tract malformations

Abstract: Obstructive uropathy causes tubular resistance to aldosterone and severe metabolic imbalance may be precipitated by an episode of pyelonephritis. In the last 3 years we investigated 52 episodes of pyelonephritis (positive urine culture, elevated C reactive protein, fever, elevated neutrophil count) in 50 children between 15 days and 15 months of age. Ultrasonography voiding cystography and renal scintiscan were performed in all cases and i.v. urography in some. A salt-losing syndrome with hyponatremia and hyperkalemia (Na 6.3 meq/liter) was observed in 17 infants < 3 months, accompanied by plasma aldosterone concentration of 5000 to 23,000 pg/ml (normal value, < 1000 pg/ml). All these children had a severe urinary tract (UT) malformation (ureteropelvic junction stenosis in 7 cases, vesicoureteral reflux in 7, posterior urethral valves in 2, double system in 1). Thirteen infants < 3 months, 7 with no urinary tract malformations, did not have electrolyte imbalance. Pyelonephritis was diagnosed in 20 other patients ages 4 to 15 months, including 16 with severe UT malformations; 4 had normal UTs. We conclude that a salt-losing syndrome with tubular resistance to aldosterone can occur during pyelonephritis in young infants with congenital UT malformation, that the risk diminishes considerably or disappears after 3 months of age and that in the absence of UT malformation pyelonephritis does not cause acute sodium loss of clinical relevance.

Mutational analysis of the HGSNAT gene in Italian patients with mucopolysaccharidosis IIIC (Sanfilippo C syndrome). Mutation in brief #959. Online.

Abstract: Mucopolysaccharidosis (MPS) describes any inherited lysosomal storage disorder resulting from an inability to catabolize glycosaminoglycans. MPS III (or Sanfilippo syndrome) is an autosomal recessive disease caused by a failure to degrade heparan sulphate. There are four subtypes of MPS III, each categorized by a deficiency in a specific enzyme involved in the heparan sulphate degradation pathway. The genes mutated in three of these (MPS IIIA, MPS IIIB, and MPS IIID) have been cloned for some time. However, only very recently has the gene for MPS IIIC (heparin acetyl CoA: alpha-glucosaminide N-acetyltransferase, or HGSNAT) been identified. Its product (previously termed transmembrane protein 76, or TMEM76) has little sequence similarity to other proteins of known function, although it is well conserved among all species. In this study, a group of MPS IIIC patients, who are mainly of Italian origin, have been clinically characterized. Furthermore, mutational analysis of the HGSNAT gene in these patients resulted in the identification of nine alleles, of which eight are novel. Three splice-site mutations, three frameshift deletions resulting in premature stop codons, one nonsense mutation, and two missense mutations were identified. The latter are of particular interest as they are located in regions which are predicted to be of functional significance. This research will aid in determining the molecular basis of HGSNAT protein function, and the mechanisms underlying MPS IIIC.

Restoration of bacterial killing activity of human respiratory cystic fibrosis cells through cationic vector-mediated cystic fibrosis transmembrane conductance regulator gene transfer.

Abstract: In vitro and in vivo studies have demonstrated that gene transfer of the CFTR (cystic fibrosis transmembrane conductance regulator) cDNA into human respiratory cells through nonviral vectors can occur safely and can be done repeatedly. Although functional evaluation of CFTR in cystic fibrosis (CF) patients enrolled in phase I clinical trials using cationic liposomes has shown a partial correction of nasal potential difference, a biological assay indicating a therapeutic relevance of CFTR gene transfer is still missing. Our aims were to study the induction of killing activity toward Pseudomonas aeruginosa (PA) in CF cells by cationic vector-mediated CFTR gene transfer and to use this assay as a therapeutic end point. Luciferase expression and GFP FACS analysis were used to evaluate the optimal vector and the efficiency of gene transfer into non-CF human respiratory cells growing from nasal polyp explants at the air-liquid interface. To prove that transgenic CFTR was expressed in CF cell cultures under the same experimental conditions, a specific RT-PCR was performed. Challenge of the outgrowths with a known amount of PA showed a bacterial clearance activity by non-CF respiratory cells, while in the case of CF cells it even resulted in bacterial growth. Cationic vector-mediated CFTR cDNA determined the recovery of bacterial clearance activity only under those conditions yielding 5% or more of GFP-positive cells. The results shown in this study might be helpful in considering cationic vectors as therapeutic nonviral vectors for transferring CFTR into human CF respiratory cells, as well as for restoring the bacterial killing activity defective in cystic fibrosis.

Role of clathrin- and caveolae-mediated endocytosis in gene transfer mediated by lipo- and polyplexes

Abstract: We investigated the effects of inhibitors of clathrin-mediated endocytosis (chlorpromazine and K(+) depletion) and of caveolae-mediated uptake (filipin and genistein) on internalization of FITC-poly-l-lysine-labeled DOTAP/DNA lipoplexes and PEI/DNA polyplexes by A549 pneumocytes and HeLa cells and on the transfection efficiencies of these complexes with the luciferase gene. Uptake of the complexes was assayed by fluorescence-activated cell sorting. Lipoplex internalization was inhibited by chlorpromazine and K(+) depletion but unaffected by filipin and genistein. In contrast, polyplex internalization was inhibited by all four inhibitors. We conclude that lipoplex uptake proceeds only by clathrin-mediated endocytosis, while polyplexes are taken up by two mechanisms, one involving caveolae and the other clathrin-coated pits. Transfection by lipoplexes was entirely abolished by blocking clathrin-mediated endocytosis, whereas inhibition of the caveolae pathway had no effect. By contrast, transfection mediated by polyplexes was completely blocked by genistein and filipin but was unaffected by inhibitors of clathrin-mediated endocytosis. Fluorescence colocalization studies with a lysosomal marker, AlexaFluor-dextran, revealed that polyplexes taken up by clathrin-mediated endocytosis are targeted to the lysosomal compartment for degradation, while the polyplexes internalized via caveolae escape this compartment, permitting efficient transfection.