Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: UMLS:C0021051 (immunodeficiency)
71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To evaluate the possible need for vaccination against diphtheria and tetanus of patients infected with the human immunodeficiency virus (HIV), antibodies were measured in blood samples from 78 Danish HIV-infected men, born 1950-59, who could be expected to have received primary vaccination before they contracted the HIV infection. No patients (95% confidence interval: 0-4) had tetanus antibodies below the protective level, whereas 24 of the 78 patients (16-33) were unprotected against diphtheria. In the background population of the same age group and sex, 5% and 10% have been found unprotected against tetanus and diphtheria, respectively. No relationship between disease stages and antibody levels could be found. Neither was there any difference between patients with normal and reduced numbers of CD4+ lymphocytes. From 25 patients two blood samples were taken at an interval of at least one year. Anti-tetanus titres showed a decrease comparable to that found in the background population, whereas the change in anti-diphtheria titres was more variable with rising antibody concentrations in nine patients. The fall off in antibodies did not increase with progression of the disease. It is concluded that HIV-positive younger men who have followed the vaccination program against tetanus prior to the HIV infection can be expected to be protected, whereas revaccination against diphtheria must be considered.
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PMID:Immunity against diphtheria and tetanus in human immunodeficiency virus-infected Danish men born 1950-59. 135 66

To determine the role of cytokines in the immunodeficiency of children infected with human immunodeficiency virus type 1 (HIV-1), we compared the antigen-specific (tetanus toxoid-induced) T-lymphocyte blastogenesis of HIV-1-infected patients with and without the addition of exogenous interleukin-1 and interleukin-2. Acquisition of in vitro antigen-specific immunologic function was seen in some patients after the addition of exogenous cytokines. The antigen-specific immunodeficiency in some HIV-1-infected children is due to defects in cytokine production rather than to an absence of antigen-specific T lymphocytes.
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PMID:Correction of antigen-specific T-lymphocyte function by recombinant cytokines in children infected with human immunodeficiency virus type 1. 850 84

Dendritic cells (DC) have a potent antigen-presenting capacity for recruiting resting T cells into immune responses. They also promote expansion of already activated memory T cells. By contrast, macrophages (M phi) are only effective in stimulating memory responses. Infection and depletion of DC occur in human immunodeficiency virus (HIV)-infected individuals and recruitment of T cells into primary responses is blocked. Here comparisons between DC and M phi in stimulating secondary T-cell responses in HIV infection were made. Adherent M phi, and DC isolated by a new method, were separated from peripheral blood of patients in different stages of HIV infection and from uninfected controls and added to allogeneic lymphocytes in mixed leucocyte reactions (MLR). Some were pulsed with influenza virus or tetanus toxoid and used to stimulate autologous T cells. Responses were measured from uptake of [3H]thymidine in 20 microliters hanging drop cultures. DC, but not M phi, from normal individuals stimulated MLR but both populations stimulated secondary responses to recall antigens. DC from all HIV seropositive individuals caused little or no stimulation of any lymphocyte responses. However, M phi from HIV seropositive asymptomatic individuals and those with persistent generalized lymphadenopathy stimulated responses to recall antigens. There was no stimulation using cells from acquired immune deficiency syndrome (AIDS) patients. Blocked DC but not M phi function may underlie progressive immunological non-responsiveness in HIV infection. Without recruitment of resting T cells, loss of memory T cells may be cumulative; failure of secondary activation (e.g. by M phi) would lead to lost T-cell activity. Identification and circumvention of the defect in DC could offer new therapeutic approaches.
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PMID:Antigen-presentation by macrophages but not by dendritic cells in human immunodeficiency virus (HIV) infection. 153 9

Causes of cellular immunodeficiency frequently associated with cancer remain poorly understood. One possible mechanism is tumor cell membrane shedding of immunosuppressive molecules, such as the sialic acid-containing glycosphingolipids, gangliosides. To explore this interesting hypothesis and establish structure-activity relationships, we examined the effects of a series of highly purified human gangliosides on T cell function. In all, ten individual molecular species of two major biosynthetic pathways were compared for their ability to inhibit human T cell proliferative responses. They include GM1, GD1a, GD1b, and GT1b (the predominant normal brain species), and GM4, GM3, GM2, GD3, GD2 and GQ1b. Strikingly, each HPLC-purified molecule, from the simplest monosialoganglioside to the most complex polysialoganglioside, had potent inhibitory activity; even the ganglioside with the most elemental carbohydrate structure (GM4, one sialic acid linked to a monosaccharide) strongly inhibits T cell proliferative responses to tetanus toxoid (ID90 = 1.5 microM). The data also reveal a complex interplay between elements of oligosaccharide structure in determining immunosuppressive activity. Sialic acid is critical to maximal activity, and (i) immunosuppression is most potent in gangliosides containing a terminal sialic acid. (ii) Total desialylation almost abolishes activity and (iii) partial alteration (lactone formation) reduces activity. (iv) Activity is generally but not always higher with higher numbers of sialic acid residues/molecule, and (v) some larger neutral glycosphingolipids retain measurable immunosuppressive activity. Overall, the potent inhibition by gangliosides supports the hypothesis that shedding of these molecules by tumors creates a highly immunosuppressive microenvironment around the tumor, thereby inhibiting the function of infiltrating host leukocytes and contributing to diminished T cell responses in cancer.
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PMID:Immunosuppression by human gangliosides: I. Relationship of carbohydrate structure to the inhibition of T cell responses. 157 61

Human monocytes infected in vitro with human immunodeficiency virus (HIV) soon after adherence to plastic substrate demonstrated a significantly decreased ability to restimulate autologous immune T-lymphocyte proliferation after exposure to soluble (tetanus toxoid) and particulate [herpes simplex virus (HSV)] antigen. Incubation with the cyclo-oxygenase inhibitor, indomethacin (2-5 microM), prevented inhibition of antigen-stimulated lymphocyte proliferation. The inhibitory activity was identified in ultrafiltrates containing the low molecular weight fraction (less than 3000 MW) of supernatants from HIV-infected monocyte cultures. This activity was significantly and markedly reduced in similar ultrafiltrates prepared from indomethacin-treated cultures. Increased concentrations of prostaglandin E2 (PGE2) were detected in ultrafiltrates from HIV-infected monocyte cultures compared with uninfected cultures and cultures preincubated with indomethacin. Ultrafiltrates were inhibitory when added during the presentation of antigen to T lymphocytes but not when removed from monocyte cultures prior to the addition of lymphocytes. In addition, ultrafiltrates inhibited antigen-stimulated lymphocyte proliferation and PHA-induced lymphocyte proliferation to the same extent. These data indicate that cyclo-oxygenase products of arachidonic acid, including PGE2, are produced in excess by HIV-infected monocytes and that PGE2 and perhaps other cyclo-oxygenase products are implicated in the inhibition of antigen-stimulated lymphocyte proliferation via a direct effect on T lymphocytes.
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PMID:HIV infection of monocytes inhibits the T-lymphocyte proliferative response to recall antigens, via production of eicosanoids. 157 89

The antibody response to the capsular polysaccharide of Haemophilus influenzae type b was evaluated after vaccination with the capsular polysaccharide or its tetanus toxoid conjugate in 41 randomized patients with recurrent infections, IgA deficiency, common variable immunodeficiency, or the Wiskott-Aldrich syndrome. Serum antibodies were measured using a Farr assay for total antibodies and an enzyme-linked immunosorbent assay for antibodies of the three main immunoglobulin classes and of each IgG subclass. Antibody levels reached concentrations generally considered as protective in the majority of cases, the best response being observed after two injections of the conjugate vaccine with a 1-month interval. Vaccination with the conjugate therefore seems to be promising for the prevention of Haemophilus influenzae type b infections in such patients.
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PMID:Immunogenicity of Haemophilus influenzae type b capsular polysaccharide and its tetanus toxoid conjugate in patients with recurrent infections or humoral immunodeficiency. 159 74

Patients with common variable immunodeficiency (CVI) have decreased immunoglobulin levels resulting in frequent infections. Although previous studies have suggested that the B cell is intrinsically defective, numerous T cell deficiencies, including reduced interleukin-2 (IL-2) production, have been described. Since the addition of T cell cytokines to CVI B cells can increase Ig secretion in vitro, hypogammaglobulinemia in CVI may be due to defective T cell functions. To assess this possibility directly, we treated five CVI patients intravenously with a new biologic, human recombinant IL-2 conjugated to polyethylene glycol. Doses were 250,000 IU/m2 weekly for Weeks 1-4, 500,000 IU/m2 for Weeks 5-8, and 10(6) IU/m2 for Weeks 9-12. During and after treatment, B cells of all patients secreted 10- to 1000-fold more Ig in vitro. There was also a striking improvement in T cell helper activity since T cells of treated patients could induce 10- to 10,000-fold increases in Ig secretion by B cells from normal donors. No increase was seen in serum Igs during the study, but the anti-tetanus antibody of the IgG isotype could be detected in cell culture supernatants. Whether the effects of infused polyethylene glycol IL-2 are mediated through T or B cells, or both, is still unknown. However, these data reinforce the concept that CVI B cells may be competent, but, lacking essential T cell growth factors, in vivo maturation to Ig production does not occur.
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PMID:Restoration of immunoglobulin secretion in vitro in common variable immunodeficiency by in vivo treatment with polyethylene glycol-conjugated human recombinant interleukin-2. 160 51

Common variable immunodeficiency (CVID) patients are unable to produce specific immunoglobulins after antigen contact in vivo. The aim of this study was to investigate whether in some cases of CVID a decreased de novo synthesis of IL-2 might be the cause of immunodeficiency and whether this deficiency can be corrected by IL-2 supplementation in vitro. Mononuclear cells from 17 CVID patients and from 10 healthy controls were cultured with monoclonal anti-CD3 antibody OKT3, pokeweed mitogen (PWM) or tetanus toxoid (TT) to stimulate IL-2 synthesis. In parallel, in vitro IgG and IgM synthesis was stimulated with Staphylococcus aureus Cowan I (SAC), PWM or TT in the presence or absence of IL-2. While lymphocytes of 11 out of 17 patients produced low to normal amounts of IL-2 upon stimulation with anti-CD3, only three patients showed low IL-2 production in response to PWM and five in response to TT. Regarding immunoglobulin synthesis in vitro, five patients completely failed to produce IgM or IgG upon stimulation with PWM, SAC or TT irrespective of the addition of IL-2. By contrast, four patients did not show any defect in vitro and synthesized normal amounts of IgM and IgG with any of the three stimuli. Finally, eight patients could be reconstituted for PWM-, SAC- and TT-induced IgM and/or IgG synthesis in vitro, by adding IL-2 to the culture system. This enhancing effect of IL-2 could be blocked by adding anti-IL-2 receptor antibodies to the cultures. Our findings indicate that a defective IL-2 synthesis after antigen stimulation may be one reason for the impaired immunoglobulin production in some cases of CVID.
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PMID:Possible role of IL-2 deficiency for hypogammaglobulinaemia in patients with common variable immunodeficiency. 163 64

Helper T-cell function was evaluated in 34 children infected with human immunodeficiency virus type 1, by assessing interleukin-2 production after stimulation of peripheral blood mononuclear cells with recall antigens (influenza virus, tetanus toxoid), allogeneic HLA, and phytohemagglutinin. In addition, helper T-cell function was correlated retrospectively with the incidence of opportunistic and bacterial infections. Four patterns of helper T-cell function were observed: (1) 7 (21%) of the 34 children responded to all stimuli, (2) 7 (21%) of them responded to alloantigens and phytohemagglutinin but not to recall antigens, (3) 7 (21%) responded to phytohemagglutinin but not to recall antigens or alloantigens, and (4) 13 (37%) did not respond to any of these stimuli. There were no significant differences related to different routes of acquisition among patients. Patients with functional helper T-cell defects had a history of more opportunistic (p = 0.03) and bacterial (p less than 0.001) infections than did patients with intact helper T-cell function. Thus distinct patterns of helper T-cell dysfunction exist in children infected with human immunodeficiency virus type 1 and correlate with higher frequency of infections. Comparisons of in vitro helper T-cell responses to these stimuli may be useful for detecting early functional helper T-cell defects and for monitoring progression of disease.
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PMID:Helper T-cell responses in children infected with human immunodeficiency virus type 1. 167 68

Twenty-one asymptomatic adults who had recently received multiple polysaccharide, live viral, and protein-derived vaccines were identified as being infected with human immunodeficiency virus (HIV). The mean subject age was 24 years (range 18-33); 20 of 21 (95%) were male. The mean T4 count was 523/mm3 with a mean T4/T8 ratio of 0.6. Serologic responses to immunization with meningococcus group C, adenovirus types 4 and 7, tetanus, and diphtheria were evaluated for the HIV seropositive subjects and were compared with the responses of similarly vaccinated age-, sex-, and race-matched HIV-seronegative controls. Significantly fewer (p less than 0.03) HIV subjects responded to meningococcus C (bactericidal antibody) and adenovirus 4 (neutralizing antibody) vaccines than did normals; the HIV-infected subjects who did respond produced functional antibody comparable to that of normals. Booster responses of HIV subjects to tetanus and diphtheria were comparable to those of normals. HIV-infected vaccine nonresponders did not differ from HIV-infected responders in total white blood cell, T4, T4/T8, total serum IgG, or delayed-type hypersensitivity skin test reactivity. All HIV subjects had negative cultures for live vaccine viruses (rubella, measles, adenovirus, and poliovirus). Postimmunization, no clinically apparent adverse reactions to vaccination were detected.
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PMID:Safety and immunogenicity of multiple conventional immunizations administered during early HIV infection. 167 80


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