Biomedical subjects

M Giordano

Publications and source records attributed to M Giordano.

At least 37 records · Page 2Linked to original sources

PubMed2003

Comparison of the flow properties of aqueous suspension corticosteroid nasal sprays under differing sampling conditions.

Many aqueous suspension corticosteroid nasal sprays become less viscous when shaken and sprayed, then return to a more viscous state after application. This time-dependent, reversible loss of viscosity under shear (e.g., shaking or spraying) can be quantified in the rheological property of thixotropy. The flow properties of 5 corticosteroid nasal sprays were measured over a range of shear rates. The formulations tested included Nasonex, Vancenase AQ, Nasacort AQ, Rhinocort Aqua, and Flonase. The yield stress values, as well as an estimate of thixotropy, were compared by using three different sampling techniques, including one that simulated patient use (shaking for 30 sec, spraying, and immediately transferring the sample to the rheometer). The rheological properties of all products indicated that when initially shaken and dispensed, they flowed more freely, followed by recovery of viscosity that would likely inhibit the suspensions from flowing out of the nasal cavity. Under all three tested conditions, Nasonex exhibited the highest yield stress, the largest apparent initial and final viscosities, and the highest apparent thixotropy. The study protocol that simulated patient-use conditions produced the following rank order of measured thixotropy: Nasonex > Flonase > Vancenase AQ > Rhinocort Aqua > Nasacort AQ. The thixotropy of Nasonex was 3.4 to 21.4 times greater and the final viscosity was 3.2 to 17.4 times greater than the values of the other tested products.

Administration, Intranasal↗

PubMed2003

Neurotoxicity induced by Cefepime in a very old hemodialysis patient.

Neurotoxicity is an unusual complication of cephalosporin therapy. Only few cases of neurotoxicity induced by Cefepime have been described and probably the frequency of Cefepime-induced status epilepticus is underestimated. We report a case of an 82 year-old male, ESRD patient on chronic hemodialysis program affected by pneumonia, who received a treatment with intravenous Cefepime (1 g/day) and developed a seizure 4 days after the starting antibiotic therapy. Cefepime-induced neurotoxicity was suspected and its administration was immediately discontinued. In order to increase Cefepime clearance a hemodialysis session was urgently started and an improvement of his conscious level was observed. On the following day, after a second hemodialysis session his clinical condition and the status of neurotoxicity were completely recovered. The patient was discharged from the hospital in stable clinical condition one week later. At variance with the cases previously reported, the daily dose of Cefepime administrated to our patient was 50% lower and respected drug prescription dosage. Thus, we speculate on the hypothesis that advanced age of our patient and metabolic encephalopathy induced by chronic uremia made him more sensitive to the neurotoxicity induced by the drug. In conclusion, our case suggests that, in very old patients on long-term hemodialysis, it should be considered, to avoid neurotoxicity, to monitor the clinical neurological status, to use Cefepime at lower dosage than that allowed in patients with severe renal impairment (1 g/day) and, when possible, to evaluate Cefepime plasma levels. However, in these patients, other agents of the same class should be considered such as Cefotaxime and Ceftriaxone which are characterized by both an hepatic and renal excretion. In alternative to cephalosporins, antibiotics with the same action spectrum in the absence of neurological toxicity (i.e. Meropenem) should be recommended.

Aged↗

PubMed2003

[Surgical treatment of anal fistulas. Personal experience on 1,000 patients over a 20-year period].

BACKGROUND: Considering their long experience acquired during the period October 1981 and October 2001 related to the treatment of 1,000 patients suffering from anal fistulas, the authors reasses the problem of this affection from an etiopathogenic, classifying, diagnostic and therapeutic point of view. METHODS: Surgical treatment of Arnous's French School was performed; these methods foresee the division of the operative times and slow sphincteric sectioning by an elastic constriction. RESULTS: Results were excellent: 99.2% of complete recoveries and very few failures and complications: 0.5% incomplete recovery, 0.3% relapse, 1.3% soiling, 1.5% gas temporary incontinence. CONCLUSIONS: The main premise to obtain the patient's recovery is to perform a faultless technique and to follow assiduously and minutely the long postoperative period of surgical wounds.

Follow-Up Studies↗

PubMed2003

[Surgical treatment of pilonidal sinus with open surgical technique].

BACKGROUND: Personal experience and results about the surgical treatment of pilonidal sinus using the open technique operation are reported. METHODS: Between January 1984 and June 2001, 577 patients (457 males and 120 females) underwent this surgical technique. Eighty-five patients presented recurrences of the under-lying disease previously treated with closed technique in other centres. In order to reduce the risks of recurrence, pilonidal sinus was widely resected in order to remove every fistulous track laterally or towards the anal edge. The surgical wound has to be wide, carefully drained, without vertical walls: the outer part of the wound should be wider than its bottom. The persistence of a hairless scar is a suitable result to avoid relapses. RESULTS: This surgical technique allowed very good RESULTS: Postsurgical morbidity was not observed in these patients; the median time to achieve healing was 8+/-2 weeks. Furthermore, after a 3 year follow-up, only 4 patients (0.69%) relapsed. Recurrent dressings are needed; anyway they neither represent a limit of this technique nor lead to a long term absence from working. The postsurgical period of resting is quite similar to that usually prescribed after other surgical techniques and mainly depends on the patient nature. The treatment with connective tissue repairing drugs may be useful to obtain an effective healing. CONCLUSIONS: In the authors' experience, the open surgical technique may obtain the definitive removal of pilonidal sinus, even if particularly wide, with a safe postsurgical course and a very hight percentage (99.31%) of complete healing without any relapse.

Convalescence↗

PubMed2002

The IL12B gene does not confer susceptibility to coeliac disease.

Coeliac disease (CD) is a chronic inflammatory disorder where dietary gluten is not tolerated. In the lesion there are gluten reactive T cells predominantly secreting gamma-interferon. Both HLA and non-HLA genes contribute to CD susceptibility. Interleukin-12 (IL-12) regulates gamma-interferon production. The IL12B gene is located in a region (5q31.1-33.1) where there is evidence for linkage with CD. Allele 1 of an IL12B 3'UTR single-nucleotide polymorphism leads to increased expression of IL-12, and was recently implicated in susceptibility for type 1 diabetes (T1D). We found no evidence for association of allele 1 to CD by the transmission/disequilibrium test or case-control approach. No increased frequency was observed in patients belonging to families where the disease was linked to markers on chromosome 5q. Unlike T1D, allele 1 does not appear to confer susceptibility to CD.

Alleles↗

PubMed2002

Association tests with systemic lupus erythematosus (SLE) of IL10 markers indicate a direct involvement of a CA repeat in the 5' regulatory region.

Many lines of evidence suggest that IL10 is a strong candidate gene for systemic lupus erythematosus (SLE) susceptibility. In our previously reported study an allele (IL10.G-140bp) of the microsatellite IL10.G located at position -1100 was significantly increased in Italian SLE patients in comparison with controls. Starting from this observation, we tested if sequence variations in the vicinity of IL10.G were more strongly associated with SLE. We performed a comprehensive association study including 26 SNPs (of which four were newly identified in the present study by DHPLC analysis) spanning 8.5 Kb of the 5' flanking and the transcribed region of the IL10 gene. The association study was performed by the DNA pool method on an extended panel of Italian patients (205) and controls (631). Haplotypic associations were studied by individual typing of seven selected markers surrounding IL10.G. Gene, genotype and haplotype frequencies were not significantly different in patients and controls. Thus the IL10.G microsatellite remains to date the only IL10 marker associated with SLE in our population. A meta-analysis of all published results indicates a possible direct role of the IL10.G repeat number in SLE susceptibility.

5' Flanking Region↗

PubMed2002

Prevalence and prognostic role of microsatellite instability in patients with rectal carcinoma.

BACKGROUND: Association between microsatellite instability (MSI) and favorable postoperative survival in patients with colorectal cancer receiving adjuvant chemotherapy has been indicated. To evaluate whether an analogous positive prognostic role of MSI could be present in rectal carcinoma (RC; most RC patients receive adjuvant radiotherapy), PCR-based microsatellite analysis of archival RCs and statistical correlation with clinico-pathological parameters were performed. PATIENTS AND METHODS: DNA from paraffin-embedded paired samples of tumors and corresponding normal tissue from 91 RC patients was analyzed for MSI using five microsatellite markers (tumors were classified as MSI(+) when two or more markers were unstable). RESULTS: Seventeen (19%) RC patients exhibited a MSI(+) phenotype. Prevalence of instability was found in patients with earlier RC onset (28% in cases with diagnosis age < or =55 years versus 15% in cases >55 years), whereas similar MSI frequencies were observed in patients with different disease stage or receiving different adjuvant therapies. While MSI was detected in seven (64%) of 11 familial patients, a remarkably lower MSI incidence was observed in sporadic cases (10/80; 12.5%). A significant association with better disease-free survival (DFS) and overall survival (OS) was found for MSI(+) patients (median DFS/OS, 30/32 months) in comparison to MSI(-) ones (median DFS/OS, 18/21 months) (P <0.001). CONCLUSIONS: MSI was demonstrated to be a strong molecular prognostic marker in rectal carcinoma, independent of the administered treatment (radiotherapy, chemotherapy or both).

Adenocarcinoma↗

PubMed2001

Oleamide modulates memory in rats.

Oleamide is a recently described lipid, obtained from the cerebrospinal fluid of sleep-deprived cats. It has been observed that oleamide possesses several biological effects, such as sleep induction, and immunological suppression as well as serotonin and gamma-aminobutyric acid receptors activation. In addition, oleamide also binds to the cannabinoid receptors. In this study, we have observed that oleamide facilitates memory extinction in a passive avoidance paradigm, reduces core temperature and pain perception, but does not affect significantly locomotion. These results suggest that oleamide modulates memory processes. However, we do not know if oleamide impairs the retrieval of the memory associated to the "not go" behavior, or facilitates the fast re-learning of the "go" behavior. In addition, since these effects are also induced by marijuana and anandamide, it is very likely that oleamide may be affecting the cerebral cannabinoid system to induce its effects.

Animals↗

PubMed2001

A phase II study of sequential 5-fluorouracil, epirubicin and cyclophosphamide (FEC) and paclitaxel in advanced breast cancer (Protocol PV BC 97/01).

Sequential administration of the association of 5-fluorouracil, epirubicin and cyclophosphamide (FEC) and paclitaxel could be better tolerated than the association of an anthracycline and paclitaxel while having a similar antitumour effect. 69 patients with advanced breast cancer previously untreated with anthracyclines or paclitaxel entered a phase II multicentre study in which FEC was followed by paclitaxel. Both regimens were administered 4 times every 21 days. The median follow-up is 20 months and 38/69 patients have died. Grade III-IV toxicity was acceptable. Leukopenia occurred in 26% of patients, thrombocytopenia in 2% and anaemia in 4%. One patient had reversible heart failure during FEC therapy. Peripheral neuropathy and arthralgia-myalgia occurred in 9% and 4% of patients, respectively and one patient had respiratory hypersensitivity during paclitaxel treatment. 9 patients did not complete therapy because of: treatment refusal (n = 1), cardiac toxicity (n = 1), early death during FEC chemotherapy (n = 1), major protocol violations (n = 4), hypersensitivity reaction (n = 1) and early death during paclitaxel chemotherapy (n = 1). The overall response rate was 65% (95% CI = 53-76), and 7% of patients had stable disease. Therapy was defined as having failed in 28% of patients because they were not evaluable (13%) or had progressive disease (15%). The median time to progression and survival are 13.2 and 23.5 months, respectively. Sequential FEC-paclitaxel is a suitable strategy for patients with metastatic breast cancer who have not been previously treated with anthracyclines and/or taxanes. In fact, it avoids major haematologic toxicity and has a good antitumour effect.

Adult↗

PubMed2001

The effects of sodium arsenite exposure on behavioral parameters in the rat.

Arsenic is a metalloid widely present in the environment. It is found in well water, soil, and air, and is also released from mining residues and industrial debris, among other anthropogenic sources. It has been previously reported that the content of catecholamines in striatum, hippocampus, and other cerebral regions changes in mice and rats exposed to arsenic. Few studies have examined behavioral alterations after intoxication with arsenic, and both increased and decreased locomotor activity, as well as learning deficits, have been described. In order to characterize the behavioral alterations induced by arsenic exposure, we exposed adult male Sprague-Dawley rats to 5, 10, and 20 mg/kg of arsenic by intragastric route for 2 or 4 weeks. Exposed rats showed reduced locomotor activity, which returned to control levels at the end of the intoxication period. We also found an increase in the number of errors in an egocentric task, alterations in monoamine content in midbrain and cortex, and increases in arsenic brain concentration, which were related to time of the exposure but not dose. These results indicate that short-term arsenic exposure induces neural and behavioral changes that may reflect a neurotoxic effect, and that these alterations are correlated to dose, time of exposure, and experimental conditions.

Animals↗

PubMed2001

Combined mesencephalic and hypothalamic transplants reverse lesion-induced sexual behavior deficits in the male rat.

Studies of sexual behavior in rodent animal models have provided evidence about the relevant role played by the medial preoptic area of the anterior hypothalamus and the central tegmental field within the mesencephalon in the control of this behavior. Bilateral lesions of the anterior hypothalamus or central tegmental field as well as combined unilateral lesions of both these regions result in sexual behavior deficits. Studies using fetal hypothalamic transplants have been shown to reverse sexual behavior deficits induced either by lesions or aging. However, no previous study has evaluated the effect of combined homotopic transplants into both the anterior hypothalamus and the mesencephalon. In the present study male Wistar animals received two electrolytic lesions, one aimed at the ipsilateral medial preoptic area of the anterior hypothalamus and the other at the contralateral central tegmental field. Following these lesions, unilateral homotopic fetal hypothalamic and mesencephalic transplants were placed into the lesioned areas. Sexual behavior recovered gradually and by weeks 14-15 after transplantation, above 90% of animals with bilateral transplants showed mounts, intromissions, and ejaculations. Only animals with viable transplants located within both lesioned areas showed recovery. These results indicate that the behavioral deficits induced by combined unilateral lesions of hypothalamic and mesencephalic regions can be reversed by homotopic fetal transplants and that this recovery could be the result of the restoration of a behavioral relevant circuit between transplants and host brain nuclei separated by as much as 5 mm, which makes this an excellent model to study mechanisms underlying behavioral recovery after transplantation.

Animals↗

PubMed2001

Promotion of neutrophil apoptosis by TNF-alpha.

We examined the ability of TNF-alpha to modulate human neutrophil apoptosis. Neutrophils cultured with TNF-alpha alone undergo a low but significant increase in the number of apoptotic cells. More interestingly, when neutrophils were pretreated with TNF-alpha for 1-2 min at 37 degrees C and then were exposed to a variety of agents such as immobilized IgG, IgG-coated erythrocytes, complement-treated erythrocytes, zymosan, PMA, zymosan-activated serum, fMLP, Escherichia coli, and GM-CSF for 3 h at 37 degrees C, a marked stimulation of apoptosis was observed. Similar results were obtained in neutrophils pretreated with TNF-alpha for 30 min, 1 h, 3 h, and 18 h. Dose-dependent studies showed that TNF-alpha enhances neutrophil apoptosis at concentrations ranging from 1 to 100 ng/ml. In contrast to the observations made in neutrophils pretreated with TNF-alpha, there was no stimulation of apoptosis when TNF-alpha was added to neutrophils previously activated by conventional agonists. Experiments performed to establish the mechanism through which TNF-alpha promotes neutrophil apoptosis showed that neither reactive oxygen intermediates nor the Fas/Fas ligand system appear to be involved. Our results suggest that TNF-alpha plays a critical role in the control of neutrophil survival by virtue of its ability to induce an apoptotic death program which could be triggered by a variety of conventional agonists.

Annexin A5↗

PubMed2001

Determination of SNP allele frequencies in pooled DNAs by primer extension genotyping and denaturing high-performance liquid chromatography.

By testing DNA pools rather than single samples the number of tests for a case-control association study can be decreased to only two for each marker: one on the patient and one on the control pool. A fundamental requirement is that each pool represents the frequency of the markers in the corresponding population beyond the influence of experimental errors. Consequently the latter must be carefully determined. To this aim, we prepared pools of different size (49-402 individuals) with accurately quantified DNAs, estimated the allelic frequencies in the pools of two SNPs by primer extension genotyping followed by DHPLC analysis and compared them with the real frequencies determined in the single samples. Our data show that (1) the method is highly reproducible: the standard deviation of repeated determinations was +/-0.014; (2) the experimental error (i.e., the discrepancy between the estimated and real frequencies) was +/-0.013 (95% C.I.: 0.0098-0.0165). The magnitude of this error was not correlated to the pool size or to the type of SNP. The effect of the observed experimental error on the power of the association test was evaluated. We conclude that this method constitutes an efficient tool for high-throughput association screenings provided that the experimental error is low. We therefore recommend that before a pool is used for extensive association studies, its quality, i.e., the experimental error, is verified by determining the difference between estimated and real frequencies for at least one marker.

Alleles↗

PubMed2001

Effects of insulin and amino acids on leucine metabolism in young and middle-aged humans.

BACKGROUND: Aging is characterized by loss of muscle mass. In healthy subjects this process is associated with hormone and nutritional changes which take place over many decades. Aim of the study To investigate the effects of insulin and amino acids on amino acid metabolism in middle-aged humans. METHODS: We evaluated leucine kinetics by means of the intravenous infusion of [1-(14C)]leucine, in 8 young (age 24 +/- 2 yr, BMI 21+/- 2 kg/M2) and in 6 middle-aged (age 53 +/- 4 yr, BMI 26 +/- 1 kg/M2) healthy subjects. Studies were performed under fasting conditions (basal), and after 180 min of euglycemic hyperinsulinemic clamp (study I), or 180 min of euglycemic hyperinsulinemia in combination with an intravenous amino acid infusion (study II). RESULTS: In the basal state endogenous leucine flux (ELF, an index of proteolysis), normalized for IBW, averaged 1.71 +/- 0.12 and 1.66 +/- 0.14 micromol/kg x min in young and middle-aged subjects, respectively. Basal leucine oxidation (0.22 +/- 0.03 vs 0.28 +/- 0.03 micromol/ kg x min, p < 0.05) was lower in middle-aged with respect to young subjects. Non-oxidative leucine disposal (NOLD, an index of protein synthesis: 1.44 +/- 0.11 vs 1.43 +/- 0.11 micromol/kg x min) was similar in young and middle-aged subjects, respectively. In response to insulin (study I) the absolute and percent decline of ELF and LOX were similar in young and middle-aged subjects: ELF declined to 1.05 +/- 0.06 micromol/kg x min (-39 +/- 5 %) and 1.07 +/- 0.14 micromol/kg x min (-36 +/- 4%), in young and middle-aged, respectively (both p < 0.01 vs basal); LOX declined to 0.21 +/- 0.02 micromol/kg min (-35 +/- 3 %), and 0.18 +/- 0.05 micromol/kg x min (-28 +/- 3%, p < 0.05 vs basal) in young and middle-aged individuals respectively (both p < 0.01 vs basal). In contrast, insulin-mediated whole-body glucose uptake was lower in middle-aged subjects (6.6 +/- 1.4 mg/ kg x min) with respect to young individuals (8.1+/-1.7 mg/kg min, p < 0.05). During study II (insulin plus AA) a significant rise in NOLD was obtained in both young (1.72 +/- 0.10 micromol/kg x min, p < 0.01 vs basal) and middle-aged subjects (1.76 +/- 0.25 micromol/kg x min, p < 0.01 vs basal). Similarly, net leucine balance rose significantly in both young (+0.62 +/- 0.13 vs -0.25 +/- 0.02 micromol/kg x min, p < 0.01 vs basal) and middle-aged subjects (+0.37 +/- 0.08 vs -0.22 +/- 0.03 micromol/ kg x min, p < 0.01 vs basal) suggesting that the anabolic response to amino acids is preserved in middle-aged subjects. CONCLUSIONS: In middle-aged subjects we observed 1) a moderate decline in basal leucine oxidation; 2) a normal antiproteolytic response to insulin and a reduction in glucose uptake; and 3) a normal anabolic response to AA plus insulin. In conclusion, the data provide evidence for a normal regulation of protein anabolism and an early dissociation between the metabolic effects of insulin on glucose uptake and proteolysis in middle-aged subjects.

Adult↗

PubMed2001

Detection of AGXT bgene mutations by denaturing high-performance liquid chromatography for diagnosis of hyperoxaluria type 1.

Primary hyperoxaluria type 1 is an autosomal recessive disorder of glyoxylate metabolism, caused by a deficiency of alanine:glyoxylate aminotransferase, which is encoded by a single copy gene (AGXT. The aim of this research was to standardize denaturing high-performance liquid chromatography, a new, sensitive, relatively inexpensive, and automated technique, for the detection of AGXT mutation. Denaturing high-performance liquid chromatography was used to analyze in blind the AGXT gene in 20 unrelated Italian patients with primary hyperoxaluria type I previously studied by other standard methods (single-strand conformation polymorphism analysis and direct sequencing) and 50 controls. Denaturing high-performance liquid chromatography allowed us to identify 13 mutations and the polymorphism at position 154 in exon I of the AGXT gene. Hence the method is more sensitive and less time consuming than single-strand conformation polymorphism analysis for the detection of AGXT mutations, thus representing a useful and reliable tool for detecting the mutations responsible for primary hyperoxaluria type 1. The new technology could also be helpful in the search for healthy carriers of AGXT mutations amongst family members and their partners, and for screening of AGXT polymorphisms in patients with nephrolithiasis and healthy populations.

Adolescent↗

PubMed2001

Gender differences in spontaneous and MK-801-induced activity after striatal lesions.

At different times post-lesion, the excitotoxically lesioned striatum has been shown to undergo significant neuroanatomical and neurochemical changes, which could be expressed behaviorally. Gender and dose of excitotoxin are other variables that may modify the behavioral effects of the lesion. Consequently, the purpose of this study was to determine the effect of dose, gender, and time post-lesion on spontaneous and drug-induced locomotor behavior after intrastriatal KA lesions. Results showed that dose and time post-lesion had a significant effect on the deficits observed. Hyperactivity induced by the lesion with KA (5 nm) subsided as time post-lesion increased. Both the pattern of spontaneous and MK-801-induced locomotor activity were different for male and female rats. In female animals with KA lesions (5 nm), MK-801 did not stimulate ambulatory activity nor reduce vertical activity. Both female and male rats lesioned with KA (5 nm) showed an exaggerated response to amphetamine, at a time when spontaneous locomotor activity was reduced to control levels. Haloperidol significantly reduced locomotor activity in all groups.

Animals↗

PubMed2001

Serum HCV RNA levels correlate with histological liver damage and concur with steatosis in progression of chronic hepatitis C.

The role of HCV RNA levels and host factors in the severity of liver injury was studied. Enrolled were 298 consecutive liver biopsy-proven chronic hepatitis (CH) C patients (179 men; median age: 52 years, range 19-68; CH, 198; cirrhosis, 100) and 18 chronic hepatitis C with normal ALT. HCV genotypes were: 1a, 4.3%; 1b, 53%; 2a/c, 28%; 3a, 7%; 4, 1.3%, and mixed 6.4%. Serum HCV RNA levels were similar for all genotypes (median: 2.8 x 10(6) eq/ml; range <0.2-69). In patients with chronic hepatitis without cirrhosis, the serum HCV RNA levels reflected the grade of liver necroinflammatory activity (R = 0.45; P < 0.001) and the stage of fibrosis (R = 0.51; P < 0.001), regardless of age, gender, HCV genotype, hepatic steatosis, and hepatic iron overload. Patients with high serum HCV RNA levels (> or =3 x 10(6) eq/ml) had higher ALT values (P < 0.002) than those with lower HCV RNA levels. Patients with normal ALT showed low HCV RNA levels (median: 0.82 x 10(6) eq/ml) and histological features of minimal or mild chronic hepatitis. Cirrhotic patients showed significantly lower levels of viremia than those with chronic hepatitis with a similar HAI. The data of a subgroup of 62 patients with an established time of infection showed that for a similar duration of disease, patients with serum HCV RNA levels > or =3 x 10(6) eq/ml had a significantly higher fibrosis score than those with lower levels. HAI and fibrosis score were significantly higher in patients with HCV RNA levels > or =3 x 10(6) eq/ml and grade 3-4 steatosis than those with lower HCV RNA levels and steatosis grades. The data indicate that the liver damage is correlated with the HCV RNA levels and that a high viral load acts together with steatosis in accelerating the progression of liver injury.

Adult↗

PubMed2001

Non-malignant leukocytes delay spontaneous B-CLL cell apoptosis.

Malignant B cells from chronic lymphocytic leukemia (B-CLL) patients have a long survival in vivo, although, in culture, they spontaneously die by apoptosis. Here, we analyzed the capacity of accessory leukocytes to modulate apoptosis of B-CLL cells in vitro. To this end, we performed long-term cultures using total mononuclear cells (TMC) from B-CLL patients and TMC depleted from monocytes, NK cells and T lymphocytes (B-CLL cells). In all the patients studied (n = 25) the presence of accessory leukocytes markedly prolonged the survival of B-CLL cells. The anti-apoptotic effect was exerted by monocytes and, to a lesser degree, NK cells, partially through the release of soluble factors. Indeed, accessory leukocytes separated from leukemic cells by semipermeable membranes were still able to prolong B-CLL cell survival. By flow cytometric analysis we found that the protective effect of non-malignant cells was associated with delayed down-regulation of Bcl-2 expression on leukemic cells. By contrast, the expression of Fas and Fas ligand proteins was unchanged in most samples. Our findings suggest that monocytes and NK cells, by delaying leukemic cell apoptosis, may play a role in B-CLL cell accumulation in vivo.

Aged↗