Search PubMed⌕ Search

Biomedical subjects

F Indiveri

Publications and source records attributed to F Indiveri.

At least 73 records · Page 4Linked to original sources

Increased serum concentration of soluble HLA-DR antigens in HIV infection and following transplantation.

HLA class I and class II antigens circulate in serum as soluble molecules. Increased concentrations of soluble HLA class I molecules have been demonstrated in viral diseases, in rejection episodes following organ transplantation and in graft versus host disease. To explore the possibility of a variation of the serum concentrations of soluble HLA class II molecules in the same pathologic conditions we developed a double determinant immune assay that detects whole soluble HLA-DR molecules (sHLA-DR). The mean level of sHLA-DR antigens in sera from 23 healthy individuals was 0.64 +/- 0.72 microgram/ml. Elevated serum concentrations of sHLA-DR molecules were detected in sera from HIV infected patients in CDC2/3 and in CDC4 C1 stages (2.0 +/- 1.7 micrograms/ml and 4.6 +/- 1.7 micrograms/ml, respectively), in sera from patients affected by acute rejection after liver transplantation (5.3 +/- 3.7 micrograms/ml) and in sera from patients affected by severe acute graft versus host disease following bone marrow transplantation (8.8 +/- 3.1 micrograms/ml). The increase of sHLA-DR molecules in these sera significantly correlated with the elevation of soluble HLA class I antigens (P = 0.0004). The reported data suggest that both soluble HLA class I and class II molecules serum levels increase during viral infections and strong immune reactions and could suggest the involvement of these molecules in immunoregulation.

Bone Marrow Transplantation↗

Immune cell circulating subsets are affected by gonadal function.

Influence on the immune system activity by sex hormones has been widely reported. Fertile women are proner to the onset of autoimmune diseases than men, but this increased susceptibility disappears after menopause. The hormonal changes are very likely to be responsible for this event, but precise correlations between sex hormone levels and immune functions have not been defined. For this reason we have analyzed phenotype and natural cytotoxicity of peripheral blood lymphocytes (PBL) from 35 women in menopause, comparing them with the same parameters of 28 fertile and 8 postmenopausal women and correlating them with the hormonal pattern of each group. We have also considered 8 women with premature menopause. Hormonal levels have been detected by radioimmune assays, while PBL phenotype has been studied by immunofluorescence and FACS analysis. The natural killer (NK) cell activity has been calculated on the basis of a chromium release assay. Postmenopausal women showed a reduction of the number of total lymphocytes (1650 +/- 215 cells/mmc) in comparison to fertile women (2081 +/- 200 cells/mmc, P < 0.01). The decrease mainly involved B and CD4+ T lymphocyte subpopulations (P < 0.05 and P < 0.01, respectively). Women with premature menopause had lower percentage of CD4 lymphocytes (34% vs 47%, P < 0.01) and higher percentage of CD8 (30% vs 22%, P < 0.02) and NK cells (32% vs 14%, P < 0.009) than fertile women of the same age. The percentage of circulating lymphocytes expressing HLA class II antigens also resulted as being increased (22% vs 9%, P < 0.01). The number of total, CD2, CD4 T lymphocytes, B and NK cells correlated positively with LH and negatively with FSH serum levels (P < 0.05 and P < 0.002, respectively). PRL positively influenced CD2, CD4 and B lymphocyte numbers (P < 0.001). FSH and 17 beta-estradiol inversely affected CD8 and B lymphocyte numbers (P < 0.005 and P < 0.02, respectively). In conclusion, the increase of FSH and the decrease of PRL levels appear to be involved in the reduction of B and CD4 T lymphocytes thus lowering the risk for the onset of autoimmune diseases during and after menopause. Generalized activation of the immune system (raised expression of HLA class II antigens) with elevated numbers of cytotoxic subpopulations (CD8 and NK lymphocytes) is present in women affected by premature menopause suggesting the involvement of autoimmune dysregulation in the pathogenesis of this syndrome.

Adult↗

Increased level of serum HLA class I antigens in HIV infection. Correlation with disease progression.

Analysis of (sHLA-I) antigens in a large number of HIV-positive subjects found a significant increase of their level, but did not detect any change in their molecular profile. Monitoring at yearly intervals for four years of the sHLA-I antigen level in 14 HIV-positive subjects with a normal sHLA-I antigen level at study entry showed a significant correlation between progressive increase of sHLA-I antigen level and disease progression. Furthermore, a Kaplan-Meier plot of the frequency of development of AIDS in 34 patients whose cases were followed for 7 years showed that sHLA-I antigen level is a strong predictor of progression to AIDS. Its predictive value is comparable to that of serum beta 2-mu level, greater than that of serum neopterin, and lower than that of CD4+ T-cell percentage. The predictive value of sHLA-I antigen level in combination with serum beta 2-mu level, neopterin level, or CD4+ T-cell percentage is greater than that of each individual variable. These results suggest that measurement of the sHLA-I antigen level may provide useful prognostic information in HIV-positive subjects.

CD4 Lymphocyte Count↗

Serum HLA class I levels in elderly humans. Utilization in following the response to influenza vaccine.

Some healthy elderly people (30%-40%) do not respond to influenza vaccination. Subjects who respond to influenza vaccination show a significant increase in serum HLA class I levels 2 weeks after immunization. In the present study, serum HLA class I levels were measured prior to vaccination and 4 and 6 weeks after vaccination. The responders (HAI titers > or = 40) had higher prevaccination HLA class I levels (2.03 +/- 0.12 microgram/ml) than nonresponders (HAI titers < 40) (1.57 +/- 0.14 microgram/ml) (P = 0.03). The responders' sHLA levels remained stable at 4 (1.98 +/- 0.12 microgram/ml) and 6 (2.13 +/- 0.12 microgram/ml) weeks postvaccination. In contrast, nonresponders' sHLA levels increased at 4 weeks (1.85 +/- 0.18 microgram/ml) but declined to prevaccination levels at 6 weeks (1.59 +/- 0.16 microgram/ml). Lymphocytes isolated from the responders (n = 4) 4 weeks after vaccination had a higher in vitro proliferative response (mean SI = 20) than lymphocytes from nonresponders (n = 4, mean SI = 6.4) to the influenza vaccine. This proliferative response was significantly inhibited (mean SI = 6.3, P = 0.04) in the responders by the addition of an anti-HLA class I mAb and was associated with increased cell surface expression of HLA class I molecules. Two forms of sHLA class I molecules of relative mass of M(r) 42,000 and 40,000 were immunoprecipitated from the serum of nonresponders whereas only the M(r) 40,000 form was detected in the sera of young controls and of elderly responders.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

Immunotherapy with intralesional and systemic interleukin-2 of patients with non-small-cell lung cancer.

Eight patients affected by non-small-cell lung cancer were treated with intralesional and systemic recombinant IL-2 (rIL-2) injection with the aim of activating both tumour-infiltrating lymphocytes and circulating cytotoxic or killer cells. The schedule of treatment was as follows: a daily fine-needle transparietal intralesional rIL-2 injection (1 x 10(5) Cetus units) from day 1 to day 5 and systemic rIL-2 infusion (1 x 10(5) Cetus units kg-1 day-1) from day 6 to day 10. One to four cycles of treatment were received by each patient. Clinical and immunological evaluations were performed (a) before treatment, (b) following the intralesional rIL-2 administration, (c) 1 h after the beginning of rIL-2 infusion and (d) at the end of the systemic rIL-2 infusion. No complete remission was achieved, two patients showed a partial remission, three resulted in stable disease and three patients progressed. Natural killer and lymphokine-activated killer cell activity dramatically decreased 1 h after the beginning of rIL-2 infusion and increased at the end of treatment. A progressive increase of circulating CD8+ and HLA class II+ T cells as well as of CD8+ T cell clones, most of which displayed NK activity, was recorded following rIL-2 infusion. Present data indicate that (a) the local administration of rIL-2 coupled with systemic rIL-2 infusion may be suggested as an alternative approach for the immunotherapy of lung cancer, (b) rIL-2 induces different immunological modifications according to the route and the time of its administration and (c) rIL-2 administration increases the amount of circulating immune cells with potential antitumour activity.

Carcinoma, Non-Small-Cell Lung↗

Comparison of two glucocorticoid preparations (deflazacort and prednisone) in the treatment of immune-mediated diseases.

Different glucocorticoid preparations modify the immune reaction in different ways. In this paper, the therapeutic efficacy of two glucocorticoids, deflazacort (DFZ) and prednisone (PDN), are discussed in relation to a group of 30 patients with systemic lupus erythematosus (n = 12) or rheumatoid arthritis (n = 18). The disease sub-groups were divided into two arms, one of which was treated with DFZ and one with PDN in a double-blind protocol. The results of this study indicate that DFZ and PDN induced a clinical remission within 1 month which was maintained until the 6th month. Nevertheless, certain immunological modifications, including a significant reduction of the circulating T lymphocyte level and of the CD4/CD8 ratio, which was between 1 and 1,5 during the DFC treatment and between 1 and 2 during the PDN treatment, are more pronounced and more stable with DFZ than with PDN. Moreover, DFZ has a smaller effect on calcium and glucose metabolism than PDN since the serum glucose and calcium level of patients treated with PDN increased respectively from 90 up to 130 mg/dl and from 9,5 to 11,5 mg/dl whereas those of patients treated with DFC remained within the normal range. These findings indicate that DFZ may have advantages over PDN in the treatment of immune-mediated diseases.

Adult↗

Evidence for interactions between HLA system class I and beta-adrenergic receptors in human mononuclear leukocytes.

In order to determine the possible interactions between histocompatibility leukocyte antigen (HLA) -class I antigens and beta-adrenergic receptors, we evaluated the effects of anti-HLA class I monoclonal antibodies on beta-adrenoceptor-mediated intracellular production of cAMP in human mononuclear leukocytes. Moreover, we studied whether anti-HLA class I monoclonal antibodies inhibit the binding of a specific radioligand to the beta-adrenoceptors, and, conversely, whether both isoproterenol and propranolol interfere with the binding (evaluated by a cytofluorometric assay) of the anti-HLA class I monoclonal antibodies to the cell membrane. Our results showed that anti-HLA class I monoclonal antibodies induced a significant beta-adrenergic-dependent increase in intracellular cAMP whereas anti-HLA class II and antimelanoma monoclonal antibodies were ineffective. Moreover anti-HLA class I monoclonal antibodies inhibited, in part, the specific binding of a beta-adrenergic radioligand, although they did not induce the internalization of the beta-adrenoceptors. On the other hand, both isoproterenol and propranolol induced a significant decrease in the peripheral blood mononuclear cell expression of HLA-class I molecules. Our data suggest that important interactions between major histocompatibility complex gene products and the beta-adrenergic receptors may occur in human cells.

Adult↗

Evidence for the presence of androgen receptors in the synovial tissue of rheumatoid arthritis patients and healthy controls.

OBJECTIVE: To study the presence of androgen receptors in the synovial tissue of male and female patients with rheumatoid arthritis (RA) and matched healthy controls. METHODS: Both site I (high affinity, low binding capacity) and site II (reduced affinity, higher binding capacity) androgen receptors were investigated in soluble and nuclear fractions of homogenized synovial samples, using the dextran-coated charcoal method. The finding of pure, high-affinity site I receptors in both fractions was considered indicative of androgen receptor positivity. In order to determine what type of synovial cell was positive for androgen receptors, cryosections of synovial tissues were immunostained with a specific monoclonal anti-androgen receptor antibody (MAb), using both immunofluorescence and immunoperoxidase techniques. Double immunostaining with this MAb and specific MAb directed toward different macrophage/granulocyte antigens was also performed. RESULTS: Remarkable differences were found between male and female controls: Most males were positive for androgen receptors, and most females were negative. The fetomolar content of androgen receptor in the nuclear fraction was fairly constant, but the soluble fraction showed a higher femtomolar concentration in female RA patients than in controls of either sex, as well as in male RA patients compared with female RA patients. The androgen receptor-positive cells in both RA and control synovial cryosections were found by immunostaining to be macrophage-like synoviocytes, and were also found to be HLA-DR positive. CONCLUSIONS: The immunosuppressive action exerted by androgens might, at least in part, be mediated through their interaction with macrophage-like synoviocytes functioning as antigen-processing and antigen-presenting cells in rheumatoid synovia.

Aged↗

Simple ELISA method for the evaluation of soluble HLA class I antigens in human serum.

A simple sandwich ELISA method has been developed for the quantification of soluble HLA class I antigens (s-HLA) in human serum. The assay utilizes the monoclonal antibody Q6/64, directed to a monomorphic determinant of the HLA alpha-chain, to capture the antigen and the biotinylated NAMB1 monoclonal antibody, directed to beta 2-microglobulin, as the detection antibody. The extract of the LG-2 lymphoid cell line and pooled sera from 100 healthy subjects are utilized as standards. The arbitrary value of 100 s-HLA Relative Units/mL (RU/mL) is given to the 1:20 dilution of pooled human sera whose optical density value corresponds to the one of the extract of 1 x 10(6) LG-2 cells (6.25 micrograms/mL protein concentration). The assay is easy to perform, specific, reproducible (intra- and inter-assay variations ranging from 3.2% to 8.87%), sensitive (detection limit of 6 RU/mL), and needs a small amount of serum (0.1 mL). The mean serum levels of s-HLA found in 100 healthy normal subjects are 41.9 +/- 13.4 RU/mL. The potential uses of the method are discussed.

Adult↗

Impaired in vitro growth of peripheral blood hematopoietic progenitor cells in HIV-infected patients: evidence of an inhibitory effect of autologous T lymphocytes.

The in vitro growth of both circulating granulocyte-macrophage (CFU-GM) and erythroid (BFU-E) progenitor cells was assessed in 29 individuals infected with the human immunodeficiency virus (HIV) at different stages of infection. The effects of autologous T lymphocytes, adherent cells, and serum on the in vitro growth of hematopoietic progenitor cells were also investigated. Compared with normal controls, baseline growth was significantly reduced for both CFU-GM and BFU-E in HIV-infected patients, independent of the clinical stage of the disease. In HIV-infected subjects depletion of autologous T cells was associated with a significant increase of progenitor cell growth. Similar results were observed after selective depletion of CD8+ T cells, while readdition of T cells to T-depleted mononuclear cells reduced the number of CFU-GM. A dose-dependent colony inhibitory activity was found in conditioned medium of T cells from HIV-infected subjects. Neither autologous adherent cells nor serum from either HIV+ or HIV- subjects had any significant effect on the in vitro growth of CFU-GM. These results indicate that the in vitro growth of circulating hematopoietic progenitor cells is impaired even in the early stages of HIV infection, and that autologous T cells exert an inhibitory effect on the in vitro growth of progenitor cells, possibly via soluble mediator(s).

Acquired Immunodeficiency Syndrome↗

Major histocompatibility gene products and human immunodeficiency virus infection.

In the present paper we analyze the role of major histocompatibility gene products, the human leukocyte antigens, in the pathophysiology of the acquired immunodeficiency syndrome. No association has been found between human leukocyte antigen (HLA) frequencies and human immunodeficiency virus type 1 (HIV 1) infection, whereas significant associations have been reported in some populations between some HLA haplotypes and the appearance of either opportunistic infections or secondary cancers. With regard to the human leukocyte class I antigens, their role as restriction elements in presenting HIV 1 to virus-specific cytotoxic T lymphocytes seems to be established. An increase in the serum levels of their soluble forms that correlate with disease stage has also been demonstrated. These circulating molecules could interfere with the immune response to HIV 1 and could contribute to the development of the immunodeficiency. Antigenic similarities have been detected between human leukocyte class II antigens and HIV 1 envelope proteins. These homologies could explain both the presence in some HIV-positive sera of anti-HLA class II antibodies that mediate the lysis of CD4(+)-HLA class II+ T cells and the false-positive reaction of some HIV-negative sera, which contain anti-HLA class II antibodies, in tests for HIV 1 antibodies. Reduced levels of some complement factors (the human leukocyte class III antigens) have been detected in HIV-infected subjects. These defects could play a role in the progression of the disease and affect both the clearance of HIV 1 and complement-mediated antibody responses. The data reported in this review suggest that HLA antigens may be involved in several steps of the immune deficiency of HIV-infected subjects and thus contribute to the pathophysiology of acquired immunodeficiency syndrome.

Complement System Proteins↗

Decreased lymphocyte blastogenesis, IL2 production and NK activity following nifedipine administration to healthy humans.

The effects of a single oral dose of nifedipine on part of the immune response in healthy humans has been investigated in terms of two different immune functions: T lymphocyte proliferation and NK activity. Both functions are known to require calcium ions. Ten healthy subjects were bled before and 30 min, and 4 and 24 h after receiving 10 mg nifedipine. Lymphocyte proliferation, both in mitogen-activated lymphocyte cultures, and in autologous and allogeneic mixed lymphocyte reactions, was significantly reduced (up to 48%) 30 min after drug administration and reverted to normal 4 h later. The inhibition could be attributed to reduction in IL2 production by the T cells isolated 30 min following the administration of nifedipine, since they normally express IL2-receptors. The addition of recombinant IL2 of 200 U.ml-1 to the cell cultures restored their responsiveness. NK activity was significantly reduced 30 min and 4 h after drug administration and returned to normal at the 24th h. This function was also restored by the addition of IL2. The data suggest that calcium channel blockers may inhibit, at least transiently, lymphocyte functions in vivo.

Administration, Oral↗