Genetic variability of the measles virus hemagglutinin gene in B3 genotype strains circulating in Northern Italy

Sequencing the whole measles virus hemagglutinin (H) gene, in conjunction with a 450-nucleotide region of the nucleoprotein gene (N-450), is helpful for the identification of new genotypes and as an auxiliary in outbreak characterization. In addition, it is essential to be able to predict the antigenic changes of the H protein to gain a better monitoring of the response to the vaccine. In this study, we obtained the full-length H gene sequences from 19 measles virus (MV) strains belonging to two B3 genotype variants circulating in Lombardy (Northern Italy) between July 2015 and February 2016 and evaluated the variability of the whole MV-H gene. Furthermore, we compared the obtained H amino acid sequences to all MV sequences available in the GenBank database (n = 1152 in total) and analyzed the amino acid substitutions in the H protein within clades where the Italian strains were included. We identified a higher variability in the H gene compared to the N-450 region and our results support previous studies, highlighting that the H gene is more informative for characterizing the MV B3 genotype than the N-450 sequence. Some of the amino acid substitutions were fixed in the viral population and, remarkably, some of the amino acid substitutions were typically present only in the Italian sequences. Accumulating further molecular information about MV-H gene will be necessary to enable in-depth analyses of the variability of this gene in the vaccinated population.

Genetic analysis of human and swine influenza A viruses isolated in Northern Italy during 2010-2015

Influenza A virus (IAV) infection in swine plays an important role in the ecology of influenza viruses. The emergence of new IAVs comes through different mechanisms, with the genetic reassortment of genes between influenza viruses, also originating from different species, being common. We performed a genetic analysis on 179 IAV isolates from humans (n. 75) and pigs (n. 104) collected in Northern Italy between 2010 and 2015, to monitor the genetic exchange between human and swine IAVs. No cases of human infection with swine strains were noticed, but direct infections of swine with H1N1pdm09 strains were detected. Moreover, we pointed out a continuous circulation of H1N1pdm09 strains in swine populations evidenced by the introduction of internal genes of this subtype. These events contribute to generating new viral variants-possibly endowed with pandemic potential-and emphasize the importance of continuous surveillance at both animal and human level.

On-chip purification and detection of hepatitis C virus RNA from human plasma

Hepatitis C virus (HCV) is one of the main causes of chronic liver disease worldwide. The diagnosis and monitoring of HCV infection is a crucial need in the clinical management. The conventional diagnostic technologies are challenged when trying to address molecular diagnostics, especially because they require a complex and time-consuming sample preparation phase. Here, a new concept based on surface functionalization was applied to viral RNA purification: first of all polydimethylsiloxane (PDMS) flat surfaces were modified to hold RNA adsorption. After a careful chemical and morphological analysis of the modified surfaces, the functionalization protocols giving the best RNA adsorbing surfaces were applied to PDMS microdevices. The functionalized microdevices were then used for RNA purification from HCV infected human plasma samples. RNA purification and RT were successfully performed in the same microdevice chamber, saving time of analysis, reagents, and labor. The PCR protocol for HCV cDNA amplification was also implemented in the microdevice, demonstrating that the entire process of HCV analysis, from plasma to molecular readout, could be performed on-chip. Not only HCV but also other microdevice-based viral RNA detection could therefore result in a successful Point-of-Care (POC) diagnostics for resource-limited settings.

Late onset of hepatitis B virus reactivation following hematopoietic stem cell transplantation: successful treatment with combined entecavir plus tenofovir therapy

Prophylaxis with lamivudine (LAM) is recommended for hepatitis B core antibody-positive allogenic hematopoietic stem cell transplant (HSCT) recipients, but the optimal timing for the institution and duration of the prophylaxis is still unknown. Furthermore, considering the high rate of mortality associated with hepatitis B virus reactivation (HBV-R), the most potent and long-term effective antiviral regimen should be considered. We report here a case of late onset of HBV-R after a long-term prophylaxis with LAM in a patient who underwent HSCT for non-Hodgkin lymphoma and who was successfully treated with a combination antiviral regimen including entecavir and tenofovir disoproxil fumarate.

Resistance to Fas-mediated apoptosis of human T-cell lines expressing human T-lymphotropic virus type-2 (HTLV-2) Tax protein

The susceptibility to Fas-mediated apoptosis was evaluated in seven T-cell lines (two infected with HTLV-2, one with HTLV-1, and four HTLV-free) as well as in Jurkat cells transfected with a Tax-2 expressing vector. Fas-mediated apoptosis was significantly reduced in the HTLV-1- and HTLV-2-infected lines in comparison with the HTLV-free lines regardless of the surface expression of Fas antigen (which was no different in the infected and uninfected cells). Fas-mediated apoptosis was also significantly inhibited in Jurkat cells transfected with the Tax-2 expressing vector without any modification in Fas expression. There was significantly more antiapoptotic Bcl-x(L) mRNA and protein in the transfected than in the untransfected Jurkat T cells. In conclusion, our results suggest that HTLV-2 is capable of inhibiting Fas-mediated apoptosis by means of a mechanism involving the tax-2 gene and probably the expression of bcl-x(L) messenger and protein.

Molecular epidemiology of TT virus in Italy and phylogenesis of viral isolates from subjects at different risk for parenteral exposure

The prevalence and genotype distribution of human TT virus (TTV) in Italy were analysed in 593 subjects at different risk of parenteral infection who included blood donors, patients with chronic type C hepatitis (HCV), thalassemic patients, patients on haemodialysis, human immunodeficiency virus type 1 (HIV-1)-negative intravenous drug users (IVDUs), and HIV-1-infected subjects (IVDUs, heterosexual contacts and homosexual males). Plasma TTV-DNA was detected using nested PCR with primers deduced from the N22 region of the open reading frame 1 (ORF-1) and from the untranslated region (UTR) of the viral genome. Phylogenetic analysis of the sequences obtained from ORF-1 was also undertaken. A high prevalence of plasma TTV-DNA was observed using the UTR primers, with rates varying from 83-100% in the study groups. Using the N22 primers, HIV-1 positive IVDUs and homosexual males, haemodialysed patients and thalassemic patients had a significantly higher TTV prevalence (range: 23.0-86.1%) than blood donors, who displayed a high frequency of positivity (10.6%). Sequence analysis of 127 N22-positive isolates revealed that 42.5% were of type 1, 53.5% of type 2, 2.4% of type 3, and that two isolates (1.6%) were closely related to genotypes 1-2 but distinct from the other major genotypes. TTV-2 was significantly more prevalent in patients at high risk for parenteral infection and in HIV-1 positive homosexuals. In sequential samples from 15 TTV-infected subjects, N22 sequences were detectable persistently in 12 (80.0%) and UTR sequences persisted in all 15 patients over a mean period of 29.6 months. This data indicates that TTV is widespread in Italy in parenterally exposed subjects, and that the infection frequently persists.

A PCR-colorimetric microwell plate hybridization assay for detection of Mycobacterium tuberculosis and M. avium from culture samples and Ziehl-Neelsen-positive smears

Differentiation between Mycobacterium tuberculosis and M. avium is essential for the treatment of mycobacterial infections. We have developed an easy and rapid detection assay for the diagnosis of mycobacterial diseases. This is a PCR-hybridization assay based on selective amplification of a 16S rRNA gene sequence using pan-Mycobacterium primers followed by hybridization of the amplification products to biotinylated M. tuberculosis and M. avium-specific probes. A total of 55 mycobacterial isolates were tested. For all isolates, results concordant with those of conventional identification methods were obtained. Moreover, we developed a method for extraction of DNA from Ziehl-Neelsen-positive smears which allows the recovery of intact target DNA in our PCR-hybridization assay. Our method was able to confirm all culture results for 59 Ziehl-Neelsen-positive smears from clinical specimens (35 sputum, 11 lymph node biopsy, 6 stool, 4 pus, 2 urine, and 1 pericardial fluid specimens). These data suggest that our PCR-hybridization assay, which is simple to perform and less expensive than commercial probe methods, may be suitable for the identification of M. tuberculosis and M. avium. It could become a valuable alternative approach for the diagnosis of mycobacterial infections when applied directly to DNA extracted from Ziehl-Neelsen-positive smears as well.

Human T-lymphotropic virus type 2 (HTLV-2) provirus in circulating cells of the monocyte/macrophage lineage in patients dually infected with human immunodeficiency virus type 1 and HTLV-2 and having predominantly sensory polyneuropathy

We investigated the presence of human T-lymphotropic virus type 2 (HTLV-2) DNA in the peripheral blood mononuclear cell subsets obtained from 18 patients coinfected with human immunodeficiency virus type 1 and HTLV-2, 6 of whom also had predominantly sensory polyneuropathy (PSP). HTLV-2 DNA and RNA were found in CD8- and CD19-positive cells, and, for patients with PSP, in CD14-positive cells as well. Furthermore, the patients with PSP had higher proviral loads than those without PSP.

Prevalence of hepatitis G virus RNA in human immunodeficiency virus type 1-positive intravenous drug users

OBJECTIVE

The aim of this study was to evaluate the prevalence of the new human flavivirus hepatitis G virus (HGV) in Italian intravenous drug users (IDUs) and its interaction with human immunodeficiency virus type 1 (HIV-1) and hepatitis C virus (HCV).

STUDY DESIGN/METHODS

Seventy-nine IDUs with different clinical stages of HIV-1 infection and 20 non-IDU patients with chronic HCV infection were included in the study. HGV RNA was detected by means of reverse transcription-polymerase chain reaction (RT-PCR) used for the amplification of two HGV-related sequences included in the 5'-noncoding (NCR) and NS5a regions.

RESULTS

Eighteen (22.8%) of the 79 IDUs were positive for plasma HGV RNA; there was no difference in mean serum alanine aminotransferase (ALT) levels between the HGV-positive and HGV-negative patients. No significant correlation was observed between HGV and other viral markers (hepatitis B virus [HBV], HCV, human T-cell lymphotropic virus type II [HTLV-II]) or HCV genotype. The number of patients with symptomatic HIV-1 infection in whom HGV RNA was detected was significantly lower than the number of those who were asymptomatic (6 of 49 [12.2%] versus 12 of 30 [40%]; P = 0.004). The mean plasma HGV RNA titer was higher in the asymptomatic than in the symptomatic patients (4.6 versus 3.2 log PCR-amplified units in 1 mL of plasma sample [PU/mL]; P = 0.03).

CONCLUSIONS

Our results show a considerable spread of HGV levels among Italian HIV-1-positive IDUs and do not indicate that HGV infection enhances liver impairment. We suggest that the greater prevalence of HGV RNA in IDUs with asymptomatic HIV-1 infection may reflect the relatively recent HGV infection in this population.

Detection of hepatitis C virus RNA in CD19 peripheral blood mononuclear cells of chronically infected patients

The presence of HCV RNA in peripheral blood mononuclear cells (PBMC) has been reported. To identify the cell populations carrying HCV RNA, the presence and amount of HCV RNA was investigated by limiting dilution nested reverse transcriptase-polymerase chain reaction (PCR) in PBMC subpopulations fractionated by automated cell sorting. Fifteen chronically HCV-infected patients were included in the study, 4 of whom also had mixed cryoglobulinemia. HCV RNA was present in the CD19 cells of all 15 patients, but only 5 (35.7%) of 14 and 5 (41.6%) of 12 showed HCV RNA in CD3 and CD14 cells, respectively (P < .001 by Fisher's test for each comparison). The median titer of HCV RNA was 1 PCR unit/380 CD19 cells, compared with median of 1 PCR unit/6600 PBMC as a whole. Titration was difficult in the CD3 and CD14 cells because of the frequent negativity of the first diluted sample. This study suggests that HCV RNA is selectively concentrated in B cells.

High prevalence of false-negative anti-HTLV type I/II enzyme-linked immunosorbent assay results in HIV type 1-positive patients

A high frequency of false-negative anti-HTLV-I/II ELISA results has been reported by several authors. To verify the possible underestimate of the prevalence of HTLV-II infection in subjects infected by HIV-1, we used the PCR to investigate the presence of HTLV DNA in peripheral blood mononuclear cells (PBMCs) collected from a group of 67 HIV-1-positive anti-HTLV-I/II ELISA-negative individuals; the study population included 31 patients with HIV-1-related peripheral neuropathy (PN), 15 with non-Hodgkin lymphoma (NHL), and 23 without PN or NHL. Two subjects had both PN and NHL. All of the patients who were positive at PCR were investigated for the presence of serum anti-HTLV-I/II antibodies by means of Western blot (WB). Eighteen (26.9%) of the 67 anti-HTLV-I/II ELISA-negative patients had HTLV DNA in their PBMCs and WB-detectable serum antibodies directed against one or more HTLV antigens. The individuals affected by predominantly sensory polyneuropathy (PSP) had a significantly higher prevalence of HTLV DNA than the others. All of the patients in whom HTLV-I/HTLV-II discrimination was successful had HTLV-II, with the exception of one patient who was infected by HTLV-I. The present study confirms the possibility of HTLV infection in the absence of ELISA-detectable serum anti-HTLV-I/II antibodies, especially in the particular setting of HIV-1-infected individuals. Moreover, the fact that the prevalence of HTLV DNA was significantly higher in the subjects affected by predominantly sensory polyneuropathy further supports the possibility of an association between HIV-1-related PSP and HTLV-II.

HTLV infection in ELISA-negative blood donors

Human T lymphotropic viruses (HTLVs) have a limited spread in the general populations of Western countries. Consequently, the transfusional risk for HTLV is consider to be low in Italy and the screening for anti-HTLV-I/II antibodies has not yet been introduced. In 1992, 1087 blood donors attending a transfusional center in northern Italy underwent anti-HTLV-I/II screening carried out by means of two different ELISA tests. Eleven individuals who were negative at the first test were borderline at the second, eight of them showing reactivity to Western blot (WB). Polymerase chain reaction (PCR) for the detection of HTLV DNA, subsequently performed on the peripheral blood mononuclear cells of these 11 subjects, was positive in the same 8 WB-reactive donors. Five of them were infected by HTLV-II, and three by HTLV-1. Our results confirm that the sensitivity of the ELISA tests actually used for the detection of HTLV-I/II antibodies is low, and that HTLV-infected blood donors may be frequently undetected. Moreover, in our study population, the prevalence of HTLV infection (0.73%) was greater than that which might be expected from the existing seroepidemiological data in Italy.

High prevalence of human T cell lymphotropic virus type II infection in patients affected by human immunodeficiency virus type 1--associated predominantly sensory polyneuropathy

The etiopathogenesis of peripheral neuropathy (PN) that frequently affects human immunodeficiency virus (HIV) type 1-positive patients remains undefined. Forty-seven HIV-1-positive patients with PN (8 with inflammatory demyelinating polyneuropathy and 39 with predominantly sensory polyneuropathy [PSP]) and 266 controls with symptomatic HIV-1 infection without PN were screened for antibodies to human T cell lymphotropic virus (HTLV) types I and II. The prevalence of antibodies to HTLV-II was significantly higher in patients with PSP than in controls (30.8% vs. 8.3%; P < .001). All seropositive patients with PN had HTLV-II DNA in their peripheral blood mononuclear cells by polymerase chain reaction (PCR) analysis. PCR analysis of tissues from 1 patient with PSP who died during the study showed HTLV-II proviral sequences in the femoral nerve and basal nuclei. These results support the hypothesis that HTLV-II represents an etiologic factor in the pathogenesis of a considerable proportion of PSP in patients infected with HIV-1.

HCV genotypes in bone marrow and peripheral blood mononuclear cells of patients with mixed cryoglobulinemia

OBJECTIVE

The association of the hepatitis C virus (HCV) with the cryoglobulinemic syndrome is well known, but its pathogenetic mechanism still remains to be clarified. HCV-RNA has been found in the peripheral blood mononuclear cells (PBMC) of infected subjects. We investigated the presence of the HCV genome in bone marrow cells (BMC), and the distribution of different HCV genotypes in individuals with mixed cryoglobulinemia (MC) and in noncryoglobulinemic controls.

METHODS

15 anti-HCV positive subjects with MC, 7 non-cryoglobulinemic patients with type C chronic active hepatitis (CAH) and 2 anti-HCV negative controls were studied. HCV-RNA was detected by nested PCR of the highly conserved 5'-NCR sequence. HCV typing was carried out by means of the hybridization of the same amplified region with specific probes.

RESULTS

HCV-RNA was present in the PBMC of a large proportion of the MC patients and controls without any significant differences. On the contrary, HCV-RNA was present in the bone marrow cells of all the patients with MC and in 43% of the CAH controls. The HCV 1b and 2a genotypes seem to be the most prevalent among MC patients. Nevertheless, the patients with type II MC had a very high prevalence of the 2a genotype (77%).

CONCLUSION

The results suggest that the presence of HCV-RNA in bone marrow cells may be correlated to the pathogenetic mechanism of MC. Other studies are needed to confirm the frequent association of HCV genotype 2 with MC.

Disappearance of cryoglobulins and remission of symptoms in a patient with HCV-associated type II mixed cryoglobulinemia after HIV-1 infection

OBJECTIVE

We report the case of a woman with long-lasting mixed cryoglobulinemic syndrome, who experienced clinical and laboratory remission of her cryoglobulinemia after becoming infected with human immuno-deficiency virus and developing HIV-1 induced immunosuppression.

METHODS

Serum cryoglobulin concentrations and the CD4+ cell count were monitored every three months.

RESULTS

After the diagnosis of HIV-1 infection, the immunological status of the patient was constantly depressed (CD4+ cell count dropping from 337/microL in January 1991 to 21/microL in June 1994). Serum cryoglobulins were persistently absent over 43 months of follow-up, despite the presence of HCV-RNA.

CONCLUSION

In this case, HIV-1 induced immunodeficiency seems to be responsible for the remission of the cryoglobulin syndrome and the disappearance of serum cryoglobulins. These findings indicate that CD4+ T lymphocytes may play a role in regulating the activity of cryoprecipitating rheumatoid factor secreting B cell clones.

HCV-RNA detection using different PCR methods in sera, cryoglobulins and peripheral blood mononuclear cells of patients with mixed cryoglobulinemia

OBJECTIVE

The hepatitis C virus (HCV) is frequently associated with mixed cryoglobulinemia (MC), and a number of authors have reported the presence of anti-HCV antibodies and HCV-RNA in the blood of MC patients. The presence of the HCV genome in the blood cells of individuals infected by HCV may correlate with the etiopathology of MC. We investigated the presence of HCV-related sequences in the sera, cryoglobulins and peripheral blood mononuclear cells (PBMC) of patients with MC and of individuals with type C chronic active hepatitis (CAH).

METHODS

39 patients with MC, 11 non-cryoglobulinemic HCV-positive individuals with CAH, and 2 anti-HCV negative controls were included in the study. The presence of HCV-RNA was detected by nested RT-PCR and by a commercial kit. The PCR was performed by amplifying the 5'-non coding region (5'-NCR) of HCV.

RESULTS

HCV-RNA was detected in the sera and cryoglobulins of about 90% of the patients; the commercial kit showed a higher sensitivity than nested PCR. One MC patient showed HCV-RNA only in the cryoglobulins. HCV-RNA was present in the PBMC of 14 of the 20 (70%) MC patients analyzed. No differences in serum and PBMC HCV-RNA positivity were found between MC patients and controls.

CONCLUSION

Our results confirm the spread of HCV infection among patients with MC. HCV-RNA is present in the serum, cryoglobulins and PBMC of a large proportion of MC patients. The prevalence of HCV-RNA in the PBMC of MC patients and controls did not differ significantly; this may suggest a tropism of HCV for PBMC regardless of the presence of cryoglobulinemia.

In vitro anti-HIV-1 antibody production in subjects in different stages of HIV-1 infection

We evaluated the in vitro antibody production from peripheral blood mononuclear cells (PBMC) against HIV-1 proteins in infected adults. Fifty-four HIV-1 infected patients (four recent seroconverters, 15 asymptomatics with a CD4 count higher than 500/microliters, 27 asymptomatics with a CD4 count between 200 and 500/microliters and eight symptomatic patients) were tested. PBMC were incubated in the presence or absence of 1% pokeweed mitogen (PWM) at 37 degrees C for 8 days. Western blot assay, p24 antigen ELISA and anti-p24 antibody ELISA were performed on serum and culture supernatants. Spontaneous production of anti-env antibody in culture supernatants was evidenced in all subjects. All the positive supernatants for anti-core antibodies (18/54) were derived from asymptomatic patients. PBMC from recent seroconverters and from symptomatic patients did not produce any anti-core antibody. Antibody production decreased after stimulation with PWM. The concentration of p24 antigen did not significantly increase in p24 positive supernatants following acidification (P = 0.1), suggesting that the inability to detect p24 antibody was not due to the anti-p24 antibody complexed to p24 antigen in culture supernatants. In vitro production of anti-p24 antibodies was significantly more frequent in asymptomatic subjects with high CD4+ cell counts (P = 0.02) and was absent in recent seroconverters. This last finding suggests that during the initial phases of the infection, anti-p24 antibody production may be restricted to cells residing in lymphoid organs. In addition, the lower percentage of anti-core antibody in people with low CD4+ cell counts is not merely a consequence of the binding of the antibody to an increased amount of antigen, but probably reflects an impaired production or a sequestration of producing cells in lymphoid tissue during the late stages of the infection.

Frequent detection of antibodies against HTLV antigens in patients with AIDS-related non-Hodgkin lymphoma

We studied the prevalence of anti-HTLV-I/II antibodies in 22 patients with AIDS-related non-Hodgkin lymphoma (NHL), 453 HIV-1-infected patients without lymphoma (194 of whom were diagnosed as having AIDS), and 6 HIV-1-positive and 75 HIV-1-negative patients with Hodgkin lymphoma. The frequency of serological reactivity against HTLV antigens was significantly higher in the AIDS patients with lymphoma than in those without (8 of 22, 36.4% vs. 20 of 194, 10.3%-p = 0.0027). One of the HIV-1-positive and none of the HIV-1-negative patients with Hodgkin lymphoma showed anti-HTLV-I/II reactivity. Four of the eight seropositive NHL patients showed antibodies directed against HTLV-II recombinant antigens when tested for serological discrimination in a Western blot assay. A PCR study of PBMCs from the only patient with NHL still alive at the time of the study showed HTLV-II-specific sequences in the genomic DNA. These data suggest that HTLV-II or a closely homologous retrovirus infects a high proportion of patients with AIDS-associated NHL.

Hepatitis C virus RNA in the bone marrow of patients with mixed cryoglobulinemia and in subjects with noncryoglobulinemic chronic hepatitis type C

Hepatitis C virus (HCV) infection is associated with most mixed cryoglobulinemia (MC) syndromes. In this study, HCV RNA was detected in the peripheral blood mononuclear cells of 11 (73.3%) of 15 patients with MC and in 5 (71.4%) of 7 noncryoglobulinemic patients with chronic hepatitis type C. All patients with cryoglobulinemia and 3 (42.8%) of the 7 without cryoglobulinemia (P < .05) had HCV RNA in bone marrow cells. Subjects in both groups with HCV-positive bone marrow also had HCV RNA in serum. The majority of patients with MC syndromes were infected with HCV subtypes 1b and 2a. Two patients with MC had different genotypes in serum and cells. Further studies are needed to determine which bone marrow cell population is preferentially infected by HCV and to determine if this phenomenon is involved in inducing the production of cryoglobulins.

A multicentric seroepidemiological survey of HTLV-I/II in Italy

BACKGROUND

Several studies carried out in the USA and in Europe have shown the presence of HTLV-I/II antibodies in subjects belonging to high-risk groups for HIV infection as well as blood donors. Concern about the presence of HTLV-I/II markers in the normal population, as well as the efficient transmission of HTLV-I/II by whole blood or infected blood cells have led several countries to include screening for anti-HTLV-I/II among the mandatory serological testing of blood donors.

OBJECTIVE

In order to assess the risk of HTLV-I/II infection related to blood transfusions, a multicentric survey for antibodies against HTLV-I and HTLV-II was carried out involving 10 Italian sites during the spring of 1991.

STUDY DESIGN

Serum specimens were collected from 14,598 blood donors, 1,411 injecting drug users, 1,015 thalassemics, 142 hemophiliacs and 138 hemodialysis patients. HTLV antibodies were detected by a screening EIA which combines a viral lysate with a recombinant HTLV-I env protein (p21e). The serological confirmation was performed by a semi-automated dot-blot immunoassay that detects gag p19 and p24 and env p21e specific antibodies, while the discrimination of HTLV-I and HTLV-II reactivities was carried out by EIAs employing synthetic peptides of the ENV region specific for each virus.

RESULTS

The seroprevalence of confirmed positives was 0.034% among blood donors and 3.61% among IDUs, while no sample of the other categories could be confirmed, although several were indeterminate and one thalassemic reacted against HTLV-I on peptide testing. HTLV-I reactivity was observed in one blood donor, while all 38 of the 51 confirmed seropositive IDU's reacted only to the HTLV-II synthetic peptide.

CONCLUSIONS

These data confirm a high prevalence of HTLV-II among Italian IDUs and show an HTLV-I/II seroprevalence among blood donors very similar to that which was found in the USA volunteer blood donors. A surveillance program among blood donors seems advisable in order to establish the possible need of a mandatory screening for HTLV-I/II.

HTLV-II among Italian intravenous drug users and hemophiliacs

The seroprevalence of HTLV-I/II was evaluated in 1247 Italian individuals at high risk for HIV infection. The population studied consisted of 985 intravenous drug users (IVDUs), 474 of whom on methadone maintenance and 511 in a therapeutic community, 110 HIV-infected patients in various stages of HIV-related disease and 152 hemophiliacs. Sera were screened for antibody to HTLV-I/II by enzyme immunoassay (EIA) and confirmed by Western blot and radioimmunoprecipitation assay. Confirmed positive samples were further differentiated by EIA using HTLV-I and HTLV-II specific peptides. The overall prevalence of anti-HTLV-I/II was 4.0% in IVDUs, with the highest prevalence (8.2%) among HIV-infected symptomatic patients. None of the hemophiliacs was anti-HTLV-I/II positive, even though 63.1% tested positive for HIV antibodies. The trend of seroprevalence in drug users and the evaluation of possible risk factors demonstrated that HTLV-I/II infection has been present in Italy before the onset of HIV epidemic. The overall seroprevalence showed no significant changes during the 10 year period covered by this survey but correlated with HIV seropositivity, age and duration of drug use. Peptide testing showed that HTLV infection was mainly due to HTLV-II.

Antibody response to inactivated polio vaccine (E-IPV) in children born to HIV positive mothers

In order to evaluate the response to immunization of HIV-infected children we studied the humoral response to an enhanced potency inactivated poliovaccine (E-IPV) of 43 children born of HIV seropositive mothers. All these subjects have been followed for 32 (15-48) months in order to ascertain their infection status. After a course of 2 doses of E-IPV, 88% of children had neutralizing antibody (n.a.) titers greater than 1:4 to the 3 poliovirus serotypes and 100% to at least 2 polio strains. No statistically significant differences both as rates of n.a. positive subjects and as antibody levels were found between HIV infected children and those who lost HIV antibodies. The poorest response was observed in subjects with full-blown immunodeficiency (CD4 less than 1000/mm3, reduced response to PWM). Sixteen children also received a booster dose of vaccine one year after the completion of the primary cycle. Infected and non-infected subjects responded to the same extent with high levels of n.a. to this immunization. Interestingly, the recall dose was also able to induce high n.a. titers in those HIV infected children who showed significant decreases of n.a. titers in the months following the end of the primary cycle.

Anti-LAV/HTLV-III antibodies in groups of individuals at high risk for infection in Italy

We have studied anti-LAV/HTLV-III antibody prevalence in individuals at high risk for infection, such as intravenous drug addicts, hemophiliacs and homosexual men. Among intravenous drug addicts, LAV/HTLV-III infection was first recognized in 1981 and positive serum reactions for anti-LAV/HTLV-III antibody rose in successive years to 53%. Anti-LAV/HTLV-III antibody prevalence was 13.5% in the group of homosexual men, while in hemophiliacs treated with commercial concentrates it was 37% in 1984 and had increased to 45% in 1985. There was a significant correlation between antibody status and concentrate consumption in these patients. Results of studies of anti-LAV/HTLV-III antibody patterns with the Western blot technique suggest that antibodies against core proteins (mainly p25 and p18) and the envelope protein gp40 are always present in asymptomatic individuals and in patients with the lymphadenopathy syndrome, but usually not in patients with full-blown AIDS. These last patients have typical positive reactions only against the envelope proteins gp110 and gp40.