Cytomegalovirus infection after bone marrow transplantation in children

Cytomegalovirus (CMV) is a well-known cause of disease occurring after bone marrow transplantation (BMT). The manifestations of CMV range from asymptomatic infection, defined as active CMV replication in the blood in the absence of clinical manifestations or organ failure abnormalities, to CMV disease, characterized by CMV infection with clinical symptoms or organ function abnormalities. Diagnostic procedures to assess the viral load have improved greatly with the increased use of antigenemia, CMV DNA, and immediate early-messenger RNA. Many conditions concur in determining the risk of developing CMV reactivation or disease after bone marrow transplant with serologic status of donor and recipient, type of bone marrow transplant, presence of graft-versus-host disease being the most studied. However, time and quality of immune reconstitution seems to be the pivotal factors. Pneumonia and gastrointestinal involvement are the most frequently documented clinical pictures with late-onset CMV reactivation or disease representing a new challenge. CMV prophylaxis or pre-emptive therapy adopted during the last few years in allogeneic BMT recipients has changed the natural history of the disease, reducing the risk of CMV disease, CMV-associated death, transplant-related mortality, and has prolonged the period at risk. Specific studies on children are lacking, however, the clinical pictures and features seems to be similar both in children and adults.     

Cryptosporidium parvum-specific CD4 Th1 cells from sensitized donors responding to both fractionated and recombinant antigenic proteins

T-cell-mediated immunity plays a central role in the host response to Cryptosporidium parvum. Human T-cell clones (TCC) were isolated from peripheral blood mononuclear cells of five healthy donors with prior cryptosporidiosis by use of a C. parvum crude extract, two antigen fractions obtained by ion-exchange chromatography (IEC1 and IEC2), and two recombinant peptides (SA35 and SA40) from C. parvum sporozoites. The T-cell lines derived from the one recently infected donor had a higher proportion (26 to 38%) of T cells exhibiting the gamma/delta T-cell receptor (gamma/delta-TCR) than those from donors who had recovered from cryptosporidiosis several years earlier, suggesting that the gamma/delta T-cell population is involved in the early stage of the infection. The specific TCC had the alpha/beta-TCR, had the phenotype CD45RO(+) CD4(+) CD8(-), and were characterized by either hyperproduction of gamma interferon (IFN-gamma) alone, with a Th1 profile, or IFN-gamma hyperproduction together with interleukin-4 (IL-4) or IL-5 production, with a Th0 profile. SA35, SA40, IEC1, and IEC2 may be considered good targets of the cellular response against C. parvum and may play a role in maintaining the T-cell-mediated memory response to this parasite. Furthermore, the SA35 and SA40 peptides may be regarded as immunodominant antigens involved in the maintenance of the T-cell response in healthy C. parvum-sensitized persons.     

Cryptosporidium parvum at different developmental stages modulates host cell apoptosis in vitro

We studied apoptosis in a human ileocecal adenocarcinoma tumor cell line (HCT-8) infected with Cryptosporidium parvum, from 2 to 72 h postinfection (h.p.i.). At 2 h.p.i., the percentage of annexin V-positive cells in the cell culture had increased to 10% compared to 2.5% in noninfected control culture; sorted infected cells expressed mRNA of FasL, the active form of caspase 3, and high caspase 3 activity, whereas the noninfected neighboring cells sorted from the same culture showed no signs of apoptosis. At 24 h.p.i., the percentages of early (annexin V positive) and late (DNA fragment) apoptotic cells were 13 and 2%, respectively, in the entire cell culture, and these percentages were not statistically significant in comparison with those from noninfected control cultures. At this time, sorted infected cells expressed the inactive form of caspase 3, a low caspase 3 activity, and the antiapoptotic protein Bcl-2. Noninfected cells sorted from the same culture showed expression of the active form of caspase 3, a moderate caspase 3 activity, and no Bcl-2 expression. At 48 h.p.i., the percentages of early and late apoptotic cells and caspase 3 activity had increased in the total cell culture, and both sorted infected and noninfected cells showed the active form of caspase 3. These results show that C. parvum, depending on its developmental stage, can inhibit (at the trophozoite stage) or promote (at the sporozoite and merozoite stages) host cell apoptosis, suggesting that it is able to interact with and regulate the host-cell gene expression.     

Prenatally engineered autologous amniotic fluid stem cell-based heart valves in the fetal circulation

Prenatal heart valve interventions aiming at the early and systematic correction of congenital cardiac malformations represent a promising treatment option in maternal-fetal care. However, definite fetal valve replacements require growing implants adaptive to fetal and postnatal development. The presented study investigates the fetal implantation of prenatally engineered living autologous cell-based heart valves. Autologous amniotic fluid cells (AFCs) were isolated from pregnant sheep between 122 and 128 days of gestation via transuterine sonographic sampling. Stented trileaflet heart valves were fabricated from biodegradable PGA-P4HB composite matrices (n = 9) and seeded with AFCs in vitro. Within the same intervention, tissue engineered heart valves (TEHVs) and unseeded controls were implanted orthotopically into the pulmonary position using an in-utero closed-heart hybrid approach. The transapical valve deployments were successful in all animals with acute survival of 77.8% of fetuses. TEHV in-vivo functionality was assessed using echocardiography as well as angiography. Fetuses were harvested up to 1 week after implantation representing a birth-relevant gestational age. TEHVs showed in vivo functionality with intact valvular integrity and absence of thrombus formation. The presented approach may serve as an experimental basis for future human prenatal cardiac interventions using fully biodegradable autologous cell-based living materials.     

Interleukin-6 gene alleles affect the risk of Alzheimer's disease and levels of the cytokine in blood and brain

Two different polymorphic regions of the interleukin-6 (IL-6) gene were investigated in patients with Alzheimer's disease (AD) and non-demented controls. The -174 C allele in the promoter region of IL-6 gene was over-represented in AD patients compared to controls and significantly increased the risk of AD. Moreover, the -174 CC genotype was associated with a high risk of the disease in women. The D allele of a variable number of tandem repeat (VNTR) was in strong linkage disequilibrium with the -174 C allele and slightly increased AD risk. On the other hand, the frequency of the VNTR C allele was decreased in patients with AD and was negatively associated with the risk of developing AD. Both the -174 CC and VNTR DD genotypes were also associated with increased IL-6 levels in the blood and brain from AD. These findings suggest that IL-6 may play a multifaceted role in AD by affecting the turnover of the cytokine.     

In vivo monosomy 3 detection of posterior uveal melanoma: 3-year follow-up

Background Monosomy 3 is a highly specific marker for poor prognosis in posterior uveal melanoma. Unfortunately, cytogenetic prognostication is limited to enucleated eyes or resected tumors. The aim of this study was to evaluate mid-term natural history and safety of in vivo detection of chromosome 3 status in posterior uveal melanomas undergoing plaque brachytherapy. Methods A 25-gauge transscleral fine needle aspiration biopsy (FNAB) was performed in 32 eyes affected by posterior uveal melanoma undergoing plaque brachytherapy, just before applying the radioactive plaque. Sampled material underwent fluorescence in situ hybridization (FISH) with centromeric probes for chromosome 3. All patients had a follow-up of at least 36 months. Results Mean follow-up was 47.1 ± 8.5 months. Mean largest basal diameter and mean thickness of the tumors were 12.5 ± 2.7 mm and 8 ± 2.3 mm respectively. FNAB yielded sufficient material in 26 of 32 cases (81.2%). Adequacy of the sample ranged from 91.1% (ciliary body tumors) to 76.8% (choroidal tumors). Seventeen cases had monosomy 3 (65.3%). No correlation was found between monosomy 3 and tumor dimensions or location (ciliary body vs choroidal tumors). No early and mid-term local complications were documented. Seven patients (21.8%) died during follow-up: five (15.6%) of them died due to metastatic disease (all had monosomy 3 tumors). Conclusions Posterior uveal melanomas may be adequately and safely sampled, by intra-operative transscleral FNAB, to detect in vivo monosomy 3. The authors have no financial interest in the subject of this paper. The authors have full control of all primary data and they agree to allow Graefe’s Archive for Clinical and Experimental Ophthalmology to review their data if requested.     

ProMECE-CytaBOM vs MACOP-B in Advanced Aggressive Non-Hodgkin's Lymphoma: Long Term Results of a Multicenter Study of the Italian Lymphoma Study Group (GISL)

A randomized trial was designed in order to compare the efficacy and feasibility of ProMECE-CytaBOM (P-C) and MACOP-B (M-B) in patients with advanced, aggressive non Hodgkin's lymphoma (NHL). P-C and M-B were chosen due to their association with a very high complete remission rate when compared to other published protocols. The study was conducted on 210 patients with intermediate or high-grade NHL in stage I bulky, or stages II-IV, randomized to receive either 6 courses of P-C delivered every 28 days (106 patients), or 12 weeks of M-B chemotherapy (104 patients). In both regimens doxorubicin was replaced by a 20% higher dose of epidoxorubicin (i.e. 30 mg/m² of the analog). At the end of induction therapy patients could receive additional radiotherapy to residual masses or to sites of previous bulky disease. The two groups of patients were compared for response rates, number and severity of therapy related side effects, overall survival, disease-free survival, and time to treatment failure.

Sixty-five patients (62%) treated with P-C and 69 patients (67%) treated with M-B achieved a complete remission, with no significant differences between the two treatment arms (P = 0.13). The overall objective response rate (complete + partial remission) was 74% for patients treated with P-C, and 81% for patients treated with M-B, respectively. The 4-year relapse-free survival rate was 59% for P-C and 69% for M-B, respectively (P = 0.11). We observed an eventual total of 120 treatment failures, 64 (61%) in the group treated with P-C and 56 (54%) among those treated with M-B (P = 0.29). Patients alive without disease at four years were estimated to be 42% in the P-C arm and 49% in the M-B arm (P = 0.27). The estimated 4-year overall survival was 54% for P-C and 61 % for M-B, and the differences were also not significant (P = 0.29). Patients treated with M-B experienced more and more severe side effects, including mucositis, infections, neurologic, pulmonary and cardiac abnormalities. Patients treated with P-C had a 1.3 g mean decrease of hemoglobin over the induction therapy, while patients treated with M-B experienced a 2.2 g mean decrease (P = 0.01).

In conclusion, both P-C and M-B resulted in effective treatment for patients with aggressive NHL, and provided similar activity. However P-C was more manageable in an outpatient setting and produced less acute toxic effects.