High body mass index and night shift work are associated with COVID-19 in health care workers.

OBJECTIVE: To assess the magnitude of COVID-19 spread and the associated risk factors among health care workers (HCWs), we conducted an in-hospital survey in a central Italian COVID Hospital. METHODS: Participants underwent nasopharyngeal swab and/or serum collection for SARS-CoV-2 IgG examination. We divided participants according to working status, into rotating-night shift workers (r-NSW) and day-workers. RESULTS: We found 30 cases of COVID-19 infection in a total of 1180 HCWs (2.5%). Most COVID-19-positive hospital employees were r-NSWs with significantly higher BMI than that of individuals who tested negative. After adjustment for covariates, night work and BMI > 30 were associated with a markedly greater risk of COVID-19 diagnosis (OR 3.049 [95%CI 1.260-7.380] and OR 7.15 [95%CI 2.91-17.51], respectively). CONCLUSIONS: Our results describe a low prevalence of COVID-19 infection among HCWs at a central Italian COVID Hospital. COVID-19 infection risk appears to be associated with obesity and night shift work, thus supporting the need for careful health surveillance among frontline HCWs exposed to COVID-19.

Measles immunity in an Italian teaching hospital.

BACKGROUND: Healthcare workers (HCWs) have an increased exposure risk to measles, which can put them, their patients and their relatives at risk of infection. In Italy, 4617 cases of measles were reported in 2017; 302 involving HCWs. According to the Italian National Immunization and Prevention Plan, all HCWs should have demonstrable evidence of immunity to measles. AIMS: To evaluate measles immunization status in HCWs at a large Italian teaching hospital. METHODS: We analysed clinical records and measles-specific IgG antibody titres of HCWs undergoing occupational health surveillance between 1 January and 31 August 2017. RESULTS: Among the 1532 HCWs (mean age 32.7 ± 10.4 years) included in the study, 87% (1328) had protective antibody titres. The proportion of protective titres was highest in those born before 1982. No significant gender differences in mean measles-specific IgG antibody titres were detected. CONCLUSIONS: Our study shows non-protective measles IgG antibody titres in a substantial percentage of HCWs, especially those born in the 1980s and 1990s. Due to the increased risk of measles transmission in the hospital environment, increased prevention strategies are required, including rigorous screening and prompt vaccination of non-immune workers.

Restoration of peripheral blood natural killer and B cell levels in patients affected by rheumatoid and psoriatic arthritis during etanercept treatment.

Etanercept (ETN) is an anti-tumour necrosis factor (TNF)-α agent used in rheumatoid arthritis (RA) and psoriatic arthritis (PsA). Few studies focused on the effects of anti-TNF-α on peripheral blood cells. We aimed to evaluate peripheral blood cells in RA and PsA patients during ETN treatment and to explore their relationships with disease activity. RA (n = 82) and PsA (n = 32) patients who started ETN were included into the study and evaluated prospectively before the beginning of ETN therapy and after 14, 22, 54 and 102 weeks. Patients were studied in terms of disease activity score on 28 joints (DAS28), clinical response and laboratory findings. Natural killer (NK) cells, B cells and T cells were characterized by immunophenotyping. Both the RA and the PsA patients showed reduced NK and B cell count before ETN treatment compared with controls. A negative correlation was demonstrated between DAS28 and B cell count in RA patients at baseline. Sustained significant increase of NK and B cells up to normal levels was observed in RA and PsA patients along ETN treatment. Increase of NK cell count was associated with a good-moderate clinical response to ETN in both RA and PsA patients. During ETN treatment peripheral blood NK and B cells levels were restored in RA and PsA patients. Correlations between NK and B cells with disease activity were observed, suggesting that those effects could be mediated by ETN treatment.

Herpes simplex virus 2 causes apoptotic infection in monocytoid cells.

Increasing evidence indicates that apoptosis can be associated with several viral infections. Here we demonstrate, that infection of monocytoid cells by Herpes simplex virus 2 (HSV-2) resulted, in time- and dose-dependent induction of apoptosis as an exclusive cytopathic effect. The phenomenon was confirmed using four different techniques. Conversely, apoptosis was not observed in the Vero cell line. Virus yield in monocytoid cells was delayed and reduced, although well detectable, in comparison with that observed in Vero cells. Nevertheless, released virions exhibited full infecting capability. Apoptosis induced by HSV-2 was not inhibited by cycloheximide and only partially by an UV-treatment which completely abrogated infectivity. Virus-induced apoptosis was partly inhibited by indomethacin and was associated with a down-regulation of Bcl-2. A similar, but less pronounced, apoptosis-inducing effect in monocytoid cells was also observed with HSV-1 infection. Depending on the target cells, therefore, HSV could complete a cycle of infection which is characterized by apoptosis of infected cells.

Spontaneous and anti-Fas-induced apoptosis in lymphocytes from HIV-infected patients undergoing highly active anti-retroviral therapy.

OBJECTIVE: The aim of this study was to investigate susceptibility to spontaneous or anti-Fas-induced apoptosis in peripheral blood mononuclear cells (PBMC) from HIV-positive patients before and during highly active anti-retroviral therapy (HAART). DESIGN: A longitudinal study was performed on 12 evaluable patients on HAART. This cohort was analysed prior to and at week 2, 4, 8, 16 and 24 after beginning HAART. Variations in CD4 and CD8 cells, viral load, susceptibility to spontaneous or anti-Fas-induced apoptosis in the presence of IL-2, IL-4 or IL-12 were studied. Expression of Fas and Bcl-2 were also assessed. METHODS: Levels of HIV RNA were determined by a quantitative reverse transcription-PCR assay. Apoptosis was evaluated by staining isolated nuclei with propidium iodide followed by multiparameter flow cytometry analysis. RESULTS: Spontaneous apoptosis of PBMC was promptly inhibited after the start of treatment. Similarly, anti-Fas-induced apoptosis diminished greatly during treatment. Expression of Fas decreased significantly, while that of Bcl-2 remained statistically unchanged during the first 24 weeks of therapy. Levels of apoptosis correlated inversely to CD4 cell counts and directly to viral load in a highly significant way. Expression of Fas was directly correlated to apoptosis. Interleukin (IL)-2, but not IL-4 or IL-12, protected PBMC of HIV-positive individuals from spontaneous or anti-Fas-induced apoptosis before and during HAART. CONCLUSION: These results suggest that regulation of apoptosis and of Fas expression are involved in immunoreconstitution during HAART.

Efficacy of 3'-azido 3'deoxythymidine (AZT) in preventing HTLV-1 transmission to human cord blood mononuclear cells.

The present study investigated the effect of 3'-azido 3'deoxythymidine (AZT) treatment on in vitro infection of human cord blood mononuclear cells (CBMCs) exposed to HTLV-1 by cocultivation with the MT-2 cell line. Cultures of CBMCs were grown in IL-2 and were either left untreated or were treated with concentrations of AZT ranging from 0.0078 to 32 microM. HTLV-1-infected cultures were monitored at different times of culture by evaluating proliferation activity, cell growth and the presence and expression of HTLV-1 genes. Results showed that untreated cultures infected with HTLV-1 were able to grow for several weeks, while those treated with AZT at 0.03 microM or higher concentrations were limited in their growth capacity. Moreover, the addition of AZT at the moment of infection significantly inhibited cell proliferation in a dose-dependent fashion. In the presence of AZT, detection of proviral DNA and, more remarkably, viral RNA expression were clearly reduced. In addition, treatment with AZT resulted in a noticeable decrease in Tax protein expression. Using treatment with relatively low doses of AZT, effective in exerting an antiviral action, cytotoxicity on CBMCs was not observed, whereas higher doses induced apoptosis in uninfected CBMCs. These data show that CBMCs are protected by AZT against HTLV-1 transmission even at low, non-toxic doses.

Leucocyte rheological properties are altered in patients with diffuse atherosclerosis.

To evaluate whether atherosclerosis may be associated with altered leucocyte rheology, we assessed leucocyte count (by Coulter counter), aggregation (by means of the leukergy test) and expression of adhesion molecules integrin LFA-1 and CD 44 (by means of immunofluorescence staining and flow cytometry) in 9 patients with carotid plus lower limb artery atherosclerosis (group A), 14 patients with carotid atherosclerosis only (group B) and 23 controls without atherosclerosis (group C). The level of LFA-1 (calculated as mean fluorescence channels-MFCs) on neutrophils, lymphocytes and monocytes was significantly higher (p < 0.05) in group A and B patients than in controls (group A-mean +/- SE: 383.77 +/- 9.42 vs 295.45 +/- 5.76; 474.22 +/- 8.86 vs 388.35 +/- 7.84; 457.66 +/- 12.03 vs 396.25 +/- 4.37. Group B: 322.42 +/- 6.36 vs 295.45 +/- 5.76; 421.42 +/- 7.21 vs 388.35 +/- 7.84; 415.71 +/- 7.73 vs 396.25 +/- 4.37, respectively); furthermore, the MFC of LFA-1 on neutrophils was significantly different (p < 0.05) between group A and B patients. The percentage of aggregated leucocytes was significantly higher (p < 0.05) in group A patients (4.46 +/- 1.07) than those in groups B (1.75 +/- 0.38) and C (1.43 +/- 0.25), whereas no significant difference was detected between groups B and C. Leucocyte number and expression of CD44 were not significantly different among the 3 groups. In conclusion, changes in leucocyte rheology are present in patients with atherosclerosis and may contribute to chronic ischaemia.

Umbilical cord blood: the role of apoptosis in the control of CD34+ cell counts.

BACKGROUND AND OBJECTIVE: Cord blood obtained at delivery can be used for hematopoietic precursor cells (HPC) transplantation. The major limit for its success is represented by the low cellular yield of the stem cell population. The objective of this study was to determine the role played by apoptosis in the numerical control of CD34+ cell counts. DESIGN AND METHODS: Umbilical cord blood samples were collected from 15 women at the time of the delivery and cord blood units processed. Cells, collected following 24h and 48h of incubation, were analysed by flow cytometry using the gating strategy. RESULTS: Remarkable levels of apoptosis were detected in the stem cell population and a significant difference between apoptosis mean values at 24h and 48h within CD34+ cells were found. The difference between the percentage of apoptosis in CD34+ cells and that in the remaining population was significant both at 24h and at 48h. CONCLUSIONS: CD34+ cells have a higher likelihood to undergo apoptosis in comparison to the remaining ones present in umbilical cord blood. This process of cellular death plays a major role in the control of CD34+ cell counts in placental blood and influence, for this reason, the possibility of success of a cord blood transplantation.

Recombinant interferon alpha 2a, thymopentin and low doses of cytosine arabinoside for the treatment of myelodysplastic syndromes: a pilot study.

Eighteen patients (pts) with myelodysplastic syndrome (MDS) were treated with thymopentin (TP) (50 mg subcutaneously for 5 days) and recombinant interferon alpha 2a (rIFN alpha 2a) (3 MU/m2 subcutaneously on the sixth day); the courses were delivered every week. Moreover those pts with > or = 10% blasts in the bone marrow were additionally treated with low dose cytosine arabinoside (LDARAc) (20 mg standard dose, subcutaneously, twice a day for seven days every four weeks). Sixteen pts were finally assessable for response. Seven pts (44%) were classified as good responders, 5 (31%) had a PR; the overall response rate (GR+PR) was 75%. Two pts (12.5%) showed stable disease and the 2 remaining (12.5%) had progressive disease. Six pts with an initial moderate anemia never required supportive care before and during the therapy; in contrast to 10 pts who were transfusion-dependent. After six months of therapy 2 pts decreased their transfusional needs by 50% (1 of them did not receive any transfusion over the following six months of therapy); 2 pts needed no packed red cell infusions and 1 pt decreased his transfusional support by 75%. Five pts kept an unchanged supportive care load. The overall median survival was 12.5 months. Therapy was generally well tolerated with acceptable compliance; the most frequently recorded side effects were neutropenia and thrombocytopenia grade 2-3 among the group receiving LDARAc. However no life-threatening infectious episodes or bleeding were observed. TP, rIFN alpha 2a and LDARAc can be safely administered on an outpatient basis to MDS pts and appears to have significant activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunological and endocrinological disturbances in patients after prolonged coma following head injury.

It has been previously reported that following severe brain damage, a deficit of cellular immunity could be detected in the early phase after the occurence of the lesion. We report here the results of a cross-sectional study on long term effects of severe brain damage on immunological and neuro-endocrine changes in patients who recovered from prolonged coma caused by head injury. Results obtained from post-comatose (PC) patients were compared with those obtained from two control groups made up of spinal-cord injury (SCI) patients and healthy subjects, respectively. The following parameters were studied: lymphomonocyte subsets; interleukin 2 (IL-2) production; natural killer (NK) activity and serum levels of adrenocorticotrophic hormone (ACTH), cortisol, follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin, tri-iodothyronine (T3) and thyroxine (T4). With respect to healthy controls the PC1 subgroup, i.e. patients examined 3-6 months after injury, showed a statistically significant decrease in IL-2 production, NK activity and CD25+ lymphocytes. Similar immunological disturbances were observed in SCI but not in the PC2 subgroup, i.e. patients examined later than 6 months after injury. The same sub-group of PC1 patients showed high serum levels of cortisol and PRL. These results could be related to the immunological status and may be interpreted as a transient but prolonged condition of chronic stress or "chronic alarm reaction". Copyright Rapid Science Ltd

Susceptibility to influenza A virus infection in mice immunosuppressed with cyclophosphamide.

It is known that immunocompromised hosts show an enhanced susceptibility to microbial infections. Among these, viral infections represent a particular problem because of the lack of really efficient antiviral drugs. In the present report we have studied the effect of pharmacological immunosuppression with cyclophosphamide (CY) in virus infection in vivo, using Balb/c mice infected with influenza A virus (PR8). At the dose of 0.1 hemagglutinating units of viral inoculum, intranasal administration of PR8 virus caused the death of 50 to 60% of the animals within a period of 3-10 days. A single injection of CY (200 mg/kg) significantly increased mouse mortality to 90%, when PR8 virus challenge was performed 4 days after chemotherapy pretreatment. When the PR8 virus infection was performed at different times after CY-treatment, a similar appreciable effect was not observed. Severe alterations of some immunological parameters such as NK activity and analysis of lymphoid spleen cell subsets were related to the increased susceptibility to virus infection.

Interaction between thymic hormones and other immunomodulatory agents.

We have investigated the effects of a combination in vivo treatment with thymosin alpha 1 (TA1) and murine alpha/beta interferon (IFN) on natural killer (NK) activity and on tumor growth in B-16 melanoma tumor-bearing mice. The results indicated that treatment with a single injection of IFN (3 x 10(4] 24 h before testing, enhanced NK activity in tumor-bearing mice if the test was performed 10 days after tumor inoculation, when the animals have normal NK responsiveness. On the other hand, the same treatment led to lower or no improvement of NK responses when the assay was performed 14 or 18 days after tumor inoculation, at a time when tumor growth caused NK-suppression. However, combination treatment with TA1 (200 micrograms/kg) for 4 days, followed by IFN was found to restore normal NK cell activity. On the other hand primary tumor growth was unaffected by combination therapy, while the same treatment with TA1 and IFN was able to significantly prolong survival time of B-16 tumor-bearing mice, when administered starting on day 6 after tumor inoculation. The last evidence, together with results on NK activity stimulation, indicates that combination therapy with TA1 and IFN could be an interesting approach to cancer immunotherapy.

D(-)lentiginosine-induced apoptosis involves the intrinsic pathway and is p53-independent.

We have recently found that D(-)lentiginosine, a synthetic iminosugar exerting glucosidase inhibitory activity, but not its natural enantiomer lentiginosine, is endowed with an unexpected, pro-apoptotic activity. Here, we investigated mechanisms involved in apoptosis induced by D(-)lentiginosine in MOLT-3, HT-29 and SH-SY5Y tumour cell lines. The results showed that D(-)lentiginosine increased caspase 9 expression at 18 h in all the cell lines from 1.5-3.1 folds. Cytochrome c in the cytoplasm was found to be increased from 2.3-2.6 folds in treated cells with respect to control cells. These effects were accompanied by a remarkable collapse of the mitochondrial membrane potential and by the downregulation of anti-apoptotic genes, as well as the upregulation of pro-apoptotic genes of the Bcl-2 family. U937Bcl-2 transfectants, highly expressing Bcl-2, were reluctant to undergo apoptosis even following treatment with 500 µM D(-)lentiginosine, whereas apoptosis by D(-)lentiginosine was induced also in U937 cells, naturally deficient in P53. Thus, our study establishes that the enantiomer of a natural iminosugar is endowed with a possible anti-tumorigenic effect that might be ascribed not only to their capacity to inhibit glycosidases but also to other unknown mechanisms. These data encourage further investigation on similar compounds to make them an interesting platform for the generation of new anticancer drugs.

Thymosin alpha 1 potentiates interleukin 2-induced cytotoxic activity in mice.

We have investigated the effects of interleukin 2 (IL-2) on cytotoxic activity of spleen lymphocytes, from normal and cyclophosphamide (200 mg/kg) or B-16 melanoma suppressed mice, after in vitro or in vivo pretreatment with thymosin alpha 1 (TA1). The results of this study indicate that pretreatment in vitro (100 ng/ml for 1 hr) or in vivo (200 micrograms/kg/day for 4 days) with thymosin alpha 1 (TA1), significantly increased the IL-2 (from 100 to 500 U/ml) in vitro induced cytotoxic activity of spleen lymphocytes, collected from both normal and cyclophosphamide and tumor-suppressed animals, against both YAC-1 (NK sensitive) and MBL-2 (NK resistant) cell lines. The potential use in combination of these two different biological response modifiers, useful in enhancing the immunological responses to IL-2 of lymphocytes, may provide a novel model of immunotherapeutic intervention in cancer.

AZT inhibits the transmission of human T cell leukaemia/lymphoma virus type I to adult peripheral blood mononuclear cells in vitro.

The effect of 3'-azido-3'-deoxythymidine (AZT) on in vitro infection of peripheral blood mononuclear cells (PBMCs) isolated from normal adult individuals with human T cell leukaemia/lymphoma virus type I (HTLV-I) was evaluated. Different PBMC samples were exposed to HTLV-I by cocultivation with MT-2 (a chronically infected cell line) in the presence of 20 U/ml of human recombinant interleukin 2 (IL-2) and graded concentrations of AZT. Control and drug-treated cultures, of both infected and uninfected PBMCs, were then grown for several weeks and monitored for virological and immunological parameters. The results showed a concentration-dependent anti-proliferative effect of AZT in both infected and non-infected cultures. Production of both proviral DNA and viral RNA was inhibited not only at the higher concentrations of AZT (8 microM and 32 microM) but also at concentrations as low as 0.1-2 microM. These results were confirmed by PCR and by flow cytometry analysis for the viral core protein p19. Moreover, treatment with AZT resulted in a decreased expression of CD25 in cultures exposed to HTLV-I as well as in non-infected PBMCs. On the other hand, HLA-DR was down-regulated to a greater extent in drug-treated, virus-exposed cultures in comparison with those not infected. No evidence of the antiviral activity of AZT was observed in PBMC cultures already infected by HTLV-I or in MT-2 cells. These findings demonstrate that treatment with AZT, when given at the time of infection with HTLV-I, has a marked protective effect on PBMCs.

Identification of nuclei from apoptotic, necrotic, and viable lymphoid cells by using multiparameter flow cytometry.

BACKGROUND: Methods widely used to detect apoptosis do not allow us to easily distinguish between nuclei from viable or necrotic cells. Even if apoptosis and necrosis seem to occur as alternatives at the single cell level, they could be present simultaneously in a cell population much more frequently than expected. For this reason, attention was focused on attempting to recognize, by multiparameter flow cytometry, the characteristics of viable cells and of apoptotic or necrotic dead cells. METHODS: Apoptosis and necrosis were induced in vitro in murine thymocytes and lymphocytes from adult peripheral blood by using dexamethasone or prostaglandin E2 treatment and heat shock at 60 degrees C or hydrogen peroxide, respectively. Traditional methods, such as DNA gel electrophoresis and propidium iodide staining followed by single-fluorescence analysis or annexin-V-fluorescein isothiocyanate plus propidium iodide staining by using flow cytometry, were compared with a new method. This method consisted of combined light-scatter and red fluorescence analysis by flow cytometry after isolation of nuclei by hypotonic solution as well as high-dose detergent treatment and DNA staining with propidium iodide. RESULTS: Results showed that, although traditional methods such as DNA-gel electrophoresis and single-parameter fluorescence flow cytometry analysis were unable, as expected, to discriminate among viability, apoptosis, and necrosis, our new method has enabled us to easily identify nuclei from viable, apoptotic, and necrotic cells. Results obtained by using our method were comparable to those obtained by using two-color analysis of cells after propidium iodide/annexin V staining. CONCLUSIONS: A highly reproducible, inexpensive, rapid, and easily accessible method of analysis has been developed for simultaneously detecting apoptosis and necro sis.