Restriction of T-cell receptor repertoires in idiopathic CD4+ lymphocytopenia.

We report that alpha/beta and gamma/delta T-cell repertoires of three patients with idiopathic CD4+ lymphocytopenia, who showed different clinical manifestations and outcomes over time, were highly restricted. The disruption of T-cell repertoires does not influence the susceptibility to infections: the first patient was unable to attain a protective response to mycobacterium, the second showed clinical improvement and the third did not develop opportunistic infections. These results indicate that idiopathic CD4+ lymphocytopenia could give rise to mono-/oligoclonal T-cell expansions, but the degree of repertoire disturbance is not indicative of the severity of disease progression.

Characterization of gammadelta T cells expressing CD158b, a killer cell inhibitory receptor, in a patient with chronic CD4(+) lymphocytopenia and disseminated Mycobacterium intracellulare infection.

A population of Vdelta1(+)Vgamma9(-) gammadelta T cells that represented almost the totality (84%) of circulating lymphocytes in a patient with chronic, non-HIV-related, CD4 lymphocytopenia complicated by a disseminated Mycobacterium intracellulare infection was characterized. These gammadelta(+) T cells expressed a single killer inhibitory receptor (CD158b) and their phenotype (CD8(+)CD57(+)CD27(-)CD28(-)) indicated that, although CD45RA(+), they were not naive. However, the absence of large granular lymphocyte morphology, the impaired proliferative activity, the high susceptibility to apoptosis, and the total lack of cytotoxic ability suggested that these gammadelta cells were in a resting state. A high percentage of the cells did not harbor the CD11b integrin alpha chain and exhibited a decreased capability to bind endothelial cells. This defect might represent the mechanism whereby they remained trapped in the circulation.

Ultrasound evaluation of hepatic lymph nodes in patients with anti-hepatitis C virus antibody reactivity.

BACKGROUND: Portal lymphadenopathy is frequently found in inflammatory liver diseases. However, the mechanisms underlying portal lymphadenopathy are unknown. AIMS: To evaluate the prevalence of portal lymphadenopathy in patients with serum anti-hepatitis C Virus antibody reactivity and its relationship to clinical parameters. PATIENTS AND METHODS: The presence of portal lymphadenopathy was evaluated by upper abdominal Ultrasound by the same examiner in 114 patients with anti-hepatitis C Virus reactivity: 56 patients with normal liver enzyme activity and 58 randomly selected patients with increased liver enzyme activity undergoing liver biopsy. Laboratory tests were then performed in all patients the following day. RESULTS: Portal lymph nodes were found in a significantly higher percentage of patients with increased liver enzymes (74%) than in patients with persistently normal liver enzymes (29%: p < 0.01). Aminotransferases, gamma glutamyl transpeptidase levels and the percentage of patients with HCVRNA in serum and histological scores for piecemeal and lobular necrosis were significantly higher in patients showing hepatic lymph nodes. Multivariate analysis showed that only alanine aminotransferase and lobular necrosis were independently related to the presence of hepatic lymph nodes. A significant correlation was found between lymph node size, aminotransferase activity and lobular necrosis. CONCLUSION: Ultrasound-proven portal lymph node enlargement is an indirect sign of hepatocellular damage in patients with positive serum anti-hepatitis C Virus antibodies.

Effects of recombinant granulocyte colony-stimulating factor (G-CSF) in patients treated with ProMACE-CytaBOM for HIV-related non-Hodgkin's lymphoma (NHL).

BACKGROUND AND OBJECTIVE: The use of hematopoietic growth factors in association with chemotherapy in human immunodeficiency virus (HIV)-related non-Hodgkin's lymphoma (NHL) has been recommended, but few studies have evaluated its cost-effectiveness. DESIGN AND METHODS: The effects of recombinant granulocyte colony-stimulating factor (G-CSF) were analyzed in 33 consecutive patients with HIV-related NHL treated at a single institution with the same chemotherapy program, ProMACE-CytaBOM, with G-CSF, in 21 cases diagnosed after December 31, 1991, or without G-CSF, in 12 cases diagnosed earlier. Pearson's chi-square analysis and the two-sided Student's t-test were used for statistical comparisons. The method of Kaplan-Meyer and the log-rank-test were used for survival analyses. RESULTS: G-CSF support significantly reduced the frequency of day-1 drug dose reductions (p < 0.001) and of chemotherapy delays (p < 0.001), and improved the actual delivered doses of adriamycin, cyclophosphamide and etoposide (p < 0.02). In patients with a CD4+ count < 0.01 x 10(9)/L, chemotherapy could be given at full doses in 90% of cycles with G-CSF compared to only 20% without it. G-CSF affected neither the frequency and duration of fever and hospitalization nor the complete remission and survival rates after stratification according to the CD4+ count. INTERPRETATION AND CONCLUSIONS: G-CSF support significantly improved dose-intensity in patients with HIV-related NHL treated with aggressive chemotherapy, particularly in the subgroup with a CD4+ count < 0.1 x 10(9)/L, but it did not improve their clinical outcome.

The T-cell receptor repertoires expressed by CD4+ and CD4- large granular lymphocytes derived from the same patients suggest the persistent action of an immune-mediated selection process.

The lymphoproliferative syndrome with large granular lymphocytes (LGL) is an heterogeneous disorder of unknown etiology. The analysis of T-cell receptor (TCR) genes rearrangements has shown that, in most cases, the disease is associated with clonal proliferation of CD8+CD57+ LGL. However, the putative neoplastic nature of these expansions remains questionable because clonal proliferations of CD8+ cells have recently been found also in physiologic conditions. To obtain more precise information on the mechanisms responsible for LGL expansions, we decided to compare the molecular characteristics of TCRBV chains expressed by LGL with different phenotype and function, but derived from the same patients. To this end, we characterized, at the molecular level, the TCR repertoires of fractionated T-cell populations of two unusual patients with concurrent expansions of CD4+CD57+ and CD4-CD57+ LGL. Our results show that the dominant TCRBV chains expressed by the different CD4+ and CD4- LGL populations were strictly oligoclonal. However, the molecular characteristics of the dominant V-D-J rearrangements also imply that the selection of these clones was not due to a neoplastic event. Rather, our data suggest that these particular LGL proliferations can be ascribed to a chronic T-cell-mediated immune response that involves recognition by the engaged TCR of antigens that are not necessarily presented to immune system in the classical major histocompatibility complex-restricted pathway.

High prevalence of GB virus C infection in a group of Italian patients with hepatitis of unknown etiology.

Prevalence of the recently discovered GB virus C(GBV-C) was evaluated in a cohort of 49 Italian patients with acute or chronic hepatitis of unknown etiology (non-A-E hepatitis) and in a control group of 100 healthy blood donors. The GBV-C genomes could be detected by polymerase chain reaction (PCR) with reverse transcription in 35% of the acute and 39% of the chronic hepatitis patients; only 1 of the control subjects had a positive response. All PCR products hybridized with a specific probe in a colorimetric assay, and the analysis of the sequences of the amplified cDNAs fully confirmed the specificity of the assay. Furthermore, the alignment of the predicted translation products identified two recurrent amino acid substitutions in 6 patients, suggesting the possible existence of at least 2 different GBV-C subtypes. Thus, GBV-C may be an important agent, contributing, at least in Italy, to a significant number of the cases of hepatitis of unknown etiology.

Mimicry of the immunodominant conformation-dependent antigenic site of hepatitis A virus by motifs selected from synthetic peptide libraries.

Hepatitis A virus (HAV) is a positive-strand RNA virus with a genome length of approximately 7,480 nucleotides. Although HAV morphogenesis is thought to be similar to that of poliovirus, the prototype picornavirus, the complete characterization of the antigenic structure of this virus remains elusive. All the available evidences, however, support the existence, on HAV virions and empty capsids, of an immunodominant neutralization antigenic site which is conformation dependent and whose structure involves residues of both VP1 and VP3 capsid proteins. This particular feature and the difficulty of obtaining high virus yield in tissue cultures make HAV an ideal target for developing synthetic peptides that simulate the structure of its main antigenic determinant. To this end we utilized, in the present work, the divide-couple-recombine approach to generate a random library composed of millions of different hexapeptides. This vast library was screened with a well-characterized anti-HAV monoclonal antibody. By this strategy we identified a peptide that reacted specifically with monoclonal and polyclonal anti-HAV antibodies and, in mice, induced a specific anti-virus immune response. Furthermore, the peptide could also be used in an enzyme-linked immunosorbent assay for revealing a primary immunoglobulin M immune response in sera of acutely infected human patients. Interestingly, no sequence homology was found between the identified peptide and the HAV capsid proteins VP1 and VP3. Collectively, these data represent an additional important paradigm of a mimotope capable of mimicking an antigenic determinant with unknown tertiary structure.

Interferon therapy in intravenous drug users with HIV-associated idiopathic thrombocytopenic purpura.

BACKGROUND: There is no generally accepted treatment for human immunodeficiency virus (HIV)--associated idiopathic thrombocytopenic purpura (ITP). recombinant alpha interferon (rIFN) has been used in classic ITP with conflicting results. We have tested its activity in a group of intravenous drug users (IVDUs) with HIV-associated ITP, who also had a high prevalence of chronic liver disease. METHODS: Nine patients were treated with a short course of rIFN-2b (3 MU s.c. three times a week for four weeks), and their hematological and biochemical parameters were monitored before (t0), at the end (t1), and one month after discontinuation of rIFN therapy (t2). RESULTS: Platelet counts increased significantly from 15.9 +/- 7.3 x 10(9)/L at t0 up to 67.0 +/- 38.8 x 10S(9)/L at t1 (p < 0.005), but returned to 24.7 +/- 12.7 x 10(9)/L at t2 (t1 vs t2: p < 0.005). The other parameters did not change, with the exception of the alanine aminotransferase levels, which decreased from 105 IU/L at t0 to 42 IU/L at t1 (p < 0.05). CONCLUSIONS: A short course of rIFN is an effective treatment for HIV-associated ITP in IVDUs and may also be beneficial for the frequently concomitant chronic liver disease. Since the efficacy of rIFN on the platelet count is short-lived, long-term rIFN administration would be worth testing.

[Sonographic findings in AIDS. Our experience with 125 patients]. / Riscontri ecografici nell'AIDS. Nostra esperienza in 125 pazienti.

The US findings of 125 patients with the Acquired Immunodeficiency Syndrome (AIDS) were retrospectively reviewed in order to assess the effective role of the method in the study of this disease. US findings are reported organ by organ: a few of them appear to be exclusively related to HIV infection (opportunistic infections and lymphomas), while most of them are due to other related conditions (chronic hepatopathy). As AIDS patients undergo many repeated tests, US has proven to be a satisfactory technique for the follow-up, avoiding more expensive, more invasive and complex examinations. US has proven to be a valuable technique in the screening of HIV infections for it is easily available, repeatable and cheap; moreover, US always exhibited high sensitivity. The analysis of the data herein reported stresses the value of US in the detection of unsuspected lesions. Indeed, in some patients (5 cases of unsuspected lymphomas, 4 of which with hepatic and 1 with gastric localization) US findings determined a change in diagnosis from HIV positivity to AIDS.

[Bone marrow biopsy in HIV-positive patients with thrombocytopenia. Light and electron microscopy]. / La biopsia osteo midollare nei pazienti piastrinopenici HIV positivi. Microscopia ottica ed elettronica.

Isolated thrombocytopenia (platelets less than 100,000 mmc) may be the first clinical symptom in HIV positive patients or occur in all the evolutive phases up to overt AIDS. In this paper bone marrow lesions are evaluated at light and electron microscopy in 32 HIV positive patients with isolated thrombocytopenia (group II and III CDC 1986). At light microscopy an increase in megakaryocytes with small dysplastic changes, plasmacytosis and hypereosinophilia were the bone marrow lesions detected. Electron microscoy revealed megakaryocytes with focal nuclear alterations (hypolobation and dilatation of the perinuclear cisternae) and abnormalities in the maturation of platelets associated with cytoplasmic micro-macrovacuolation, absence of viral particles or of virus correlated structures. About 9% of HIV positive patients presented with isolated thrombocytopenia as a first clinical symptom: thrombocytopenia is not believed to have unfavourable prognostic significance in the evolution to overt AIDS.

Interferon-gamma marks activated T lymphocytes in AIDS patients.

Lymphocytes expressing interferon-gamma (IFN-gamma) on their surface were evaluated in 61 patients, all IV drug abusers, infected with human immunodeficiency virus type 1 (HIV-1), and in 85 healthy subjects (61 of whom were blood donors and 24 HIV-1 seronegative IV drug abusers). Data obtained demonstrated that IFN-gamma-expressing T lymphocytes, mostly CD8+ cells, were present in HIV-1-infected patients, and that their percentage, always higher in HIV-1-infected patients than in healthy subjects (p less than or equal to 0.001), increased with progressive stages of HIV-1 infection. At the same time other markers of T-cell activation, namely interleukin-2 receptor (rIL-2), transferrin receptor, and HLA-DR were also found to be positive in some of the HIV-1-infected subjects. The presence in the HIV-1-infected patients of activated CD8+ T cells, which are resistant to HIV-1 infection, may suggest that these cells are able to respond to continuous and progressive viral expression (HIV or/and other viruses) and may be a component of the specific response to HIV-1.

Incidence and clinicopathological heterogeneity of HIV-related non-Hodgkin's lymphoma.

The characteristics of 14 HIV-seropositive patients with NHL consecutively observed between 1984 and 1988 at our Institution are described. Patients belonged to a known population of 1242 HIV-seropositive individuals in whom the incidence of NHL was 1.13%, significantly higher than in age-matched controls (P less than .0001). Within this population, a previous diagnosis of ARC or AIDS, but not of LAS, was the only significant risk factor for the development of NHL (P less than .0001). According to the status of HIV infection at the time of NHL diagnosis, two groups of patients could be clearly identified with different clinicopathological features and prognosis. In fact, NHL developing in 7 patients previously affected by ARC or AIDS, presented as localized, extranodal disease, predominantly in the CNS; large cell histology, peripheral blood cytopenia, severe immunodeficiency and poor prognosis further distinguished this subgroup. Conversely, NHL developing in 7 patients with either asymptomatic HIV-seropositivity or LAS, more often presented as disseminated disease both in nodal and extranodal sites, with Burkitt's-type histology. Cytopenia was uncommon and immunodeficiency was significantly less severe. In this subgroup complete remission (CR) was achieved with aggressive treatment in 6 of 7 patients. No relapses occurred but two opportunistic infection-related deaths were observed. Four patients are alive 6-34 months after CR, two of whom show newly developed opportunistic infections.

HIV1-Ag in cerebrospinal fluid during AIDS.

HIV infection may display neurological symptoms at any stage; the virus can be isolated from the cerebrospinal fluid (CSF) of both symptomatic and asymptomatic patients and of two third of patients with AIDS. This study sought to determine the sensitivity of HIV1-Ag in the CSF of an HIV-Ab positive population to evaluate its diagnostic and/or prognostic significance. CSF HIV1-Ag was dosed in 48 patients: 9 patients belonged to the III CDC group, 2 to group IVA, 1 to IVB and 36 to IVC1. In the last group, 14 patients had not opportunistic infections of the CNS. The tests proved positive in: 1 IVB patient and 16 IVC patients with focal lesions of the CNS or cerebral atrophy; HIV1-Ag was present in the CSF of 63% of patients displaying neurologic symptoms and it reached 84% in patients with diffuse CNS pathology.

Prevalence, clinical, and laboratory features of thrombocytopenia among HIV-infected individuals.

Prevalence and clinical features of human immunodeficiency virus (HIV)-related thrombocytopenia have been investigated among a random population of 657 anti-HIV-positive individuals. A platelet count below 100 X 10(9)/liter was detected in 72 patients (10.9%). Compared with anti-HIV-positive controls with normal platelets, a significantly higher prevalence of males (p less than 0.02) and of intravenous drug abusers (p less than 0.02) as well as a higher frequency of patients with advanced HIV-related disease (p less than 0.001) were detected among thrombocytopenic patients. Those patients whose thrombocytopenia was associated with neutropenia and/or anemia (14 cases, 2.1%) clearly differed from patients with isolated thrombocytopenia (IT) (58 cases, 8.8%) since they belonged to the more advanced groups of the CDC classification of HIV-related disorders, had lower CD4-positive lymphocyte counts, a higher frequency of cutaneous anergy, and less persistent thrombocytopenia. In the cohort of patients with persistent IT (47 cases), no single epidemiological or clinical data proved to correlate with the severity of thrombocytopenia. They did not differ significantly from anti-HIV-positive controls in their distribution among CDC groups, but the total lymphocyte and the CD4-positive lymphocyte counts were significantly lower in IT patients belonging to CDC group II (p less than 0.05 and p less than 0.02, respectively) and III (p less than 0.01 and p less than 0.005, respectively) compared with CDC group-matched controls; after a median followup of one year, the two cohorts showed similar rates of progression to CDC Group IV.