Omar Racchi

Influenza vaccine in chronic lymphoproliferative disorders and multiple myeloma.

Objective: Vaccination against influenza in patients with chronic lymphoproliferative disorders (CLPD) and multiple myeloma (MM) is still a matter of clinical uncertainty. The aim of this study was to determine the safety, immunogenicity and clinical response to a commercially available vaccine against influenza in a group of such patients.

Heterogeneity of clonal development in chronic myeloproliferative disorders

Recent reports have suggested a previously unexpected variability in the expression of the dominant neoplastic clone in myeloproliferative disorders (MPD). We evaluated 49 female patients with MPD and informative at the X‐linked androgen receptor (AR) locus to establish the X chromosome inactivation pattern of hemopoietic cells. Whereas in chronic myelogenous leukemia (CML) the granulocytes (PMN) were uniformly of monoclonal origin, a striking heterogeneity of clonal development was found in PMN from patients with other MPD, with up to 50% of them expressing a polyclonal pattern of X inactivation. Am. J. Hematol. 60:158–160, 1999.

Clonal granulocytes in polycythaemia vera and essential thrombocythaemia have shortened telomeres

The purpose of this study was to evaluate telomere length in peripheral blood granulocytes and mononuclear cells collected from 22 women with polycythaemia vera (PV) and essential thrombocythaemia (ET). PV and ET are chronic myeloproliferative diseases whose heterogeneity of stem cell origin and clonal development has been established through analysis of X‐chromosome inactivation patterns. The results from clonality assay and determination of telomere length show that only clonal granulocytes have shortened telomeres.

Is Soluble Mesothelin-Related Protein an Upfront Predictive Marker of Pleural Mesothelioma? A Prospective Study on Italian Workers Exposed to Asbestos

Objective: Soluble mesothelin-related peptide (SMRP) may be useful in the diagnosis and detection of early stage mesothelioma. We investigated the SMRP upfront predictive role for mesothelioma in asbestos-exposed workers. Methods: A total of 1,715 subjects underwent a first visit and were invited for a follow-up after 1 and 2 years, with a clinical examination and blood sampling. SMRP was measured by an ELISA assay. Results: Median SMRP at the first visit was 0.45 [interquartile range (IQR) i.e. 25th-75th percentile: 0.30-0.67 nmol/l]. In all, 1,676 subjects (97.8%) were followed up for a median period of 47.1 months. SMRP was measured at the first visit and at both follow-up visits in 1,536 subjects. At follow-up, 3 subjects were diagnosed with an epithelioid mesothelioma. In these cases, SMRP at the first visit ranged from 0.17 to 0.52 nmol/l. Malignant pleural mesothelioma was diagnosed 9-17 months after the last SMRP evaluation. No SMRP variation was observed during the follow-up. Other 61 miscellaneous cancers were diagnosed (median SMRP at first visit: 0.50 nmol/l, IQR: 0.34-0.71 nmol/l). Conclusions: Our results did not support the usefulness of SMRP as an early marker for the detection of the disease for a time interval of 1 year.

Survival of people who are HIV-1-positive and G6PD-deficient is unaffected by virus-induced oxidative stress

There is interest in the part played by free radicals and glutathione in HIV-1 infection. Because glucose-6phosphate dehydrogenase (G6PD) is the main enzyme responsible for maintaining glutathione in its reduced form (GSH), we compared the survivals of HIV-1-infected people carrying the normal G6PD allele (Gd) or the Mediterranean variant (Gd). People with Gd have almost undetectable erythrocyte G6PD activity, and mononuclear cells from peripheral blood express 20–25% of the normal amount of enzyme. People with the defect are unable to maintain adequate concentrations of GSH and should therefore be more prone to oxidation of GSH after an induced oxidative stress such as that reported to occur during HIV-1infection. From 1983 to 1996, 323 consecutive HIV-1-positive men from Northern Sardinia, an area where about 8% of men have the Gd mutation, were screened for G6PD deficiency. 27 were Gd. No significant difference was found between those with and without the mutation in age at diagnosis, risk factors for HIV-1-infection, CD4 T cells count, or incidence and type of opportunistic infections. No haemolytic crises were observed in the Gd group during the follow-up period. Disease progression was estimated from the first HIV-1-positive test until December, 1996, or death. The median survival of the patients was 93 months for both groups (range 6–166 for the Gd and 8–151 for the Gd, respectively); -test for trend: p=0·18 (figure). Overall, 55 people with Gd (18·6%) and eight with Gd (29·6%) were dead by the end of the follow-up period. 98 people in the Gd group (33·1%), and ten in the Gd (37·0%) developed AIDS. Those with Gd did not progress to AIDS more rapidly than those with Gd (64·1 months for the Gd and 61·2 for the Gd, p=0·83). Likewise, G6PD deficiency did not affect survival in those who developed AIDS: they had a median survival of 82 months with Gd (range 6–159) and 71 months with Gd (range 8–124); test for trend: p=0·27 (figure). At least under the conditions of our study, oxidative stress is unlikely to play a large part in progression of HIV-1infection. The low concentrations of GSH reported by some census. As the ISTAT procedure could provide information on parents’ place of birth only for children living with both parents (92·6% of the number of children under 15) all the denominators were adjusted for this figure. The children were classified in three groups according to place of birth of the parents, as both born in Sardinia, only one born in Sardinia, or both born in other region of Italy. We also considered an independent source: the demographic files of Milan for the years 1989–93 including all the residents (around 11% of the region’s residents), and for each year we estimated the fraction of children under 15 with at least one Sardinian parent. The average figure was 3·6%, very close to the 3·8% regional ISTAT estimate. The figure shows the observed annual rates of IDDM incidence for children according to parents’ birth place: 26·1/100 000 (CI 7·1–66·8) for the four children with both parents born in Sardinia; 15·6/100 000 (CI 8·9–25·4) for the 16 children with only one parent born in Sardinia; and 7·8/100 000 (CI 7·1–8·5) for children with no parents born in Sardinia. Children with one parent born in Sardinia had a relative risk of developing IDDM of 2·0 (CI 1·2–3·3) compared with children with both parents born outside Sardinia. The relative risk for children born from two Sardinian parents was 3·4 (CI 1·3–9·0). The expected number of cases, assuming the same rate as the Sardinian population, is 5·3 for children of both parents born in Sardinia. On the other hand, the number of observed IDDM cases with only one Sardinian parent is about less than half the number of expected cases (35·2) by the Sardinian incidence rate. By means of a telephone interview with the cases we found only a very low exposure to the Sardinian environment (time spent in the island, supply of Sardinian food before the onset of IDDM, and diabetes family history). The same data were used to provide a Lombardy incidence rate of IDDM among children less than 15 years, estimated after validation by two other independent sources. The expected incident cases, obtained by the capture-recapture method, were 586·2, with an annual incidence rate of 9·5/100 000 (CI 8·8–10·3/100 000). Our results confirm a high IDDM incidence in Sardinianheritage children who live in a low IDDM incidence region.

Exposure of erythrocytes to methylene blue shows the active role of catalase in removing hydrogen peroxide.

Summary. Methylene blue (MB) is a powerful reducing agent that is widely used in clinical practice as well as for metabolic studies of the erythrocyte. We have investigated the role of catalase as a specific enzyme for the removal of hydrogen peroxide by measuring the in vitro effects of MB on human red cells. In the presence of MB, catalase underwent inactivation even with the co‐existence of active generation of NADPH, leaving the glutathione concentration unaffected. The data obtained in the present investigation show, using a different tool (MB), that catalase is the active enzyme in H2O2 detoxification and that its integrity is largely dependent on an adequate generation of NADPH.

Intradermal influenza vaccination in complete remission cancer patients: molecular insights

We previously showed that long-lasting complete remission (CR) non-Hodgkin lymphoma (NHL) patients treated with rituximab-containing chemotherapy have an attenuated antibody response to virosomal (Bedognetti et al, J. Immunology, 2011) or MF-59 adjuvanted (Bedognetti et al, Blood, 2012) seasonal (or pandemic) influenza vaccine (as compared with healthy controls), associated with persistent CD27+ Memory B cell depletion and hypogammaglobulinemia. Here, we evaluated humoral and innate response to trivalent intradermal vaccination in NHL in CR previously treated with rituximab-containing chemotherapy (at least one year before vaccine administration), RIT group, and in CR cancer patients treated with chemotherapy without rituximab (at least one year before vaccine administration), Non-RIT group. Intradermal administration was chosen considering its promising data, compared to conventional intramuscular route, in terms of immunogenicity and safety. Humoral response was assessed by hemagglutinin inhibition assay on sera collected at time 0 (just before vaccination) and at time 28 (four weeks after vaccination). Innate response was assessed by whole-genome gene expression analysis (Affymetrix Humane Gene ST 1.0) on PBMC collected at time 0 and at time 1 (24 hours after vaccine administration). Patients treated with rituximab-containing chemotherapy had, overall, a lower antibody response, compared to patients treated with chemotherapy alone. Overall, intradermal vaccination induced dramatic changes in gene-expression profile already one day after vaccination. These changes underline the activation of IFN stimulated genes (eg, STAT1, STAT2, CXCL10, IDO1, GBP1) and modulation of NK-associated transcripts. In addition, pathway and gene-enrichment analysis show that RIT and non-RIT groups have different quantitative and qualitative transcriptomic changes 24 hours after vaccination administration. Concordantly with antibody-titer, the innate response was more intense in Non-RIT group compared with RIT group.