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Biomedical subjects

V Georgoulias

Publications and source records attributed to V Georgoulias.

At least 19 recordsLinked to original sources
PubMed1992

Abnormal expression of IL-2R beta (p70)-binding polypeptide on HIV-infected patients' cells.

The constitutively expressed IL-2R beta (p70) chain participates in the formation of high-affinity (h.a.) IL-2R and transduces IL-2-mediated signals to normal cells. Its expression on HIV-infected patients' PBMC was evaluated and was found to be decreased in both nonstimulated CD4+ and CD8+ cells. Mitogenic cell stimulation induced IL-2R beta chain expression on both CD4+ and CD8+ cells from asymptomatic and persistent generalized lymphadenopathy patients but not on those from AIDS patients. Comparison of mean fluorescence intensity of IL-2R beta positively stained cells from normals and patients did not reveal significant differences. Cross-linking of 125I-rIL-2 on patients' PHA-blasts revealed decreased signals corresponding to both IL-2-binding chains and, in some cases, neither IL-2R alpha nor IL-2R beta chains could be detected. Decreased expression of IL-2R beta polypeptide was associated with impaired accumulation of the corresponding mRNA transcripts. Binding experiments with 125I-rIL-2 under h.a. conditions showed a decreased number of IL-2-binding sites/cell which was more pronounced in patients with AIDS than in patients with less advanced clinical stages. In vitro HIV infection of normal PHA-blasts also resulted in a decreased number of h.a. IL-2R/cell. High concentrations of rIL-2 in the absence of other mitogenic stimuli induced a decreased cell proliferation and expression of the IL-2R alpha chain and did not enhance the constitutive NK and the generation of LAK activity in several patients, suggesting an impaired IL-2R beta chain-mediated cell activation.

Antibodies, Monoclonal↗
PubMed1992

Human immunodeficiency virus-infected adherent cell-derived inhibitory factor (p29) inhibits normal T cell proliferation through decreased expression of high affinity interleukin-2 receptors and production of interleukin-2.

Adherent cells from HIV-infected subjects as well as in vitro HIV-infected normal adherent cells produce spontaneously a 29-kD (p29) factor that inhibits mitogen-induced proliferation of normal T cells. p29 mediates a partial dose-dependent inhibition of total protein synthesis in both nonstimulated and PHA-activated cells that is associated with impaired PHA-induced expression of IL-2 receptor (IL-2R)alpha chain, HLA-class II molecules, and production of IL-2 by these cells; conversely, p29 does not modify the expression of IL-2R beta chain, 4F2, CD9, or transferrin receptor, or the production of IL-1 and TNF alpha by the cells. 1 h preincubation of the cells with p29 is sufficient to detect its biologic activity and added rIL-2 abrogates p29-induced inhibition of IL-2R alpha chain expression; however, p29 does not display any biologic effect on already expressed IL-2R alpha chains. The impaired expression of IL-2R alpha chain mediated by p29 is not due to a decreased accumulation of the corresponding mRNA transcripts, but is associated with a two-fold increase of intracellular cAMP. Binding experiments with 125I-rIL-2 reveals that p29 induces a 50% decrease in the number of both high and low affinity IL-2R per cell. p29 also inhibits alloantigen-induced proliferation of PBMC, whereas it does not modify IL-2-dependent proliferation of 48-h PHA-blasts that already express high affinity IL-2R. These findings indicate that p29 mediates its biologic activity during early stages of T cell activation affecting the expression of high affinity IL-2R and production of IL-2, through a nontranscriptional mechanism involving an increase of intracellular cAMP.

Cyclic AMP↗
PubMed1992

Interleukin 2 production and interleukin 2 receptor expression by human immature leukemic T cells.

In order to determine the role of interleukin 2 (IL2) on the proliferation of leukemic cells from patients with T-cell acute lymphoblastic leukemia (T-ALL) we studied the production of IL2, the function of IL2 receptors (IL2R) expressed on T-ALL cells and their IL-2-dependent in vitro proliferation. Leukemic cells from six out of 17 T-ALL/T-cell non-Hodgkin's lymphoma patients with a prothymocyte (stage I) or a mature thymocyte (stage III), but not with a common thymocyte (stage II) phenotype, could proliferate, in a dose-dependent manner, in response to recombinant IL2 (rIL2) and anti-Tac and TU27 moAbs as well as polyclonal anti-IL2 purified immunoglobulin G could inhibit this IL2-induced cell proliferation. Both crude or/and Amicon-concentrated media conditioned by T-ALL cells from 10 out of 13 tested patients contained IL2 activity as assessed by colorimetric biological and immunoenzymatic assays; this biologic activity was due to a 14.5 kDa molecule adsorbed by anti-IL2 antibodies in an immunoaffinity assay. Although less than 10% of fresh leukemic cells expressed IL2R alpha (Tac) chain, a 24 h cell incubation in the absence of any mitogenic stimulation induced IL2R alpha chain expression in five out of 13 patients (11-83% Tac+ cells). Morever, Tac mRNA transcripts could be detected in fresh cells from all 10 patients tested. Staining of fresh leukemic cells with an IL-2R beta-chain-specific monoclonal antibody and flow cytometry analysis revealed that 4-13% of leukemic cells were positive. Binding experiments with 125I-rIL2 showed a small number of high affinity IL2R on fresh cells from three T-ALL patients (114-200 sites/cell, dissociation constant = 101-181 pm). Finally, antibodies against IL2R alpha, IL2R beta and IL2 could inhibit both IL2 driven and spontaneous cell proliferation of most patients' T-ALL cells, although in some cases an heterogenous pattern of inhibition was observed. Taken together, these findings strongly suggest that an IL2/IL2R-dependent mechanism could be involved in the proliferation of some T-ALL cells.

Antigens, CD↗
PubMed1992

Phorbol myristate acetate-induced expression of high-affinity interleukin 2 receptors and production of interleukin 2 by human acute lymphoblastic leukemia T cells.

The effect of phorbol myristate acetate (PMA) on the expression of interleukin 2 receptors (IL-2R), production of IL-2 and IL-2-dependent proliferation of acute lymphoblastic leukemia T cells (T-ALL cells) from 10 patients was studied. First, the effect of PMA on the expression of cell surface markers was assessed: a decrease of CD3 and CD4, and an enhanced expression of CD8 molecule were observed on T-ALL cells. Moreover, PMA exhibited an heterogenous effect on various activation-associated molecules such as a decreased expression of transferrin receptor and T10 molecule and an induced expression of 4F2 and CD9 molecules. It is known that functional high-affinity IL-2R are composed of at least two IL2 binding molecules, the alpha (p55) and beta (p70) chains. We found that PMA induced the expression of both IL-2R alpha and IL-2R beta chains, as well as IL-2 production by T-ALL cells. These effects were time- and dose-dependent. Cross-linking experiments with 125I-labelled recombinant IL-2 (125I-rIL-2) revealed both p55 (IL-R alpha) and p70 (IL-2R beta) IL-2-binding polypeptides, whereas binding equilibrium assays on PMA-treated cells demonstrated the presence of a low number (31-413) of high-affinity binding sites/cell in five out of six cases analysed, as well as intermediate affinity IL-2R (1234-3919 sites/cell) in four out of six cases, according to the time of incubation with PMA. In two cases tested high-affinity IL-2R on PMA-treated T-ALL cells could internalize 125I-rIL-2 at 37 degrees C. PMA alone enhanced the spontaneous proliferation of T-ALL cells in three cases, whereas a clear synergy between IL-2 and PMA could be detected in three patients' cells. Moreover, exogenous rIL-2 enhanced cell proliferation of PMA-preincubated T-ALL cells in four cases studied. Taken together, these observations indicate that a short-term incubation of T-ALL cells with PMA can activate the IL-2/IL-2R system on these cells without inducing strong modifications of their differentiation status. These results thus suggest that this system may be involved in the proliferation process of some activated immature T cells.

Cell Division↗
PubMed1991

Interaction of captan with mammalian microtubules.

Using turbidometry, electron microscopy and immunofluorescent microscopy experiments we studied the effect of captan, a widely used pesticide on mammalian microtubules and microfilaments. Turbidometry at 350 nm showed a dose-dependent inhibition of tubulin assembly incubated with captan. The pesticide, given at equimolar concentration with tubulin (30 microM), caused the total inhibition of microtubule formation, while at lower concentrations (5-20 microM) the inhibition of tubulin polymerization was less extensive. At the same concentration range (5-30 microM), captan also promoted the disassembly of performed microtubules. The results of the in vitro effects of captan with microtubules were confirmed in parallel by electron microscopic studies. In vivo, captan caused also depolymerization of microtubules in cultured mouse fibroblasts as shown by indirect immunofluorescent staining of tubulin. The extent of microtubules disassembly was concentration- and time-dependent. While incubation of the cells with 10 microM captan for 3 h disturbs totally the microtubular structures, incubation with 5 microM captan needs 12 h for the same effect. Recovery of microtubules was observed, when preincubated cells were extensively washed. No interaction of this drug with equimolar concentration of G- or F-actin could be observed in vitro, as shown by polymerization experiments. In line with this, the fluorescent actin pattern in mouse fibroblasts incubated with 10 mM captan for up to 12 h did not seem to be altered. From these results it is concluded that captan interacts in equimolar concentrations with tubulin affecting the assembly and disassembly of microtubules in vitro and in cultures of mammalian cells.

Actin Cytoskeleton↗
PubMed1991

The antiglucocorticoid RU486 downregulates the expression of interleukin-2 receptors in normal human lymphocytes.

The effects of the antiglucocorticoid RU486 on the expression of low and high affinity interleukin-2 receptors (IL-2R) in phytohaemagglutinin (PHA)-activated human peripheral blood lymphocytes were investigated. We demonstrated that RU486 inhibits in a dose-dependent way the expression of both classes of IL-2R, thereby mimicking the effects of the glucocorticoid agonist dexamethasone. The maximal effect on the low affinity binding sites was observed at 10 microM (28 +/- 2% of control, P less than 0.001) and on the high affinity IL-2R at 1 microM (from 2938 +/- 74 to 437 +/- 108 binding sites per cell, P less than 0.001). This inhibition of IL-2R expression occurs at a pretranslational level since RU486 decreased the accumulation of beta-chain IL-2R mRNA transcripts. Our data support the concept that the antiglucocorticoid RU486 at pharmacological concentrations can exert agonistic-immunosuppressive effects.

Blotting, Northern↗
PubMed1991

Immune function parameters at diagnosis in patients with myelodysplastic syndromes: correlation with the FAB classification and prognosis.

We determined nine immune function parameters at diagnosis in patients with myelodysplastic syndromes (MDS) and correlated the results with the FAB classification and prognosis by univariate and multivariate analyses. Patients with refractory anaemia (RA) and refractory anaemia with ring sideroblasts (RAS) tended to have a higher CD4/CD8 ratio and a lower amount of gamma-globulins and soluble interleukin-2 receptors in serum in comparison to those suffering from the other three subgroups of MDS. FAB classification, neutrophil and CD8+ T-cell number had the best discriminatory capacity for predicting survival less than 1 year, and FAB classification, neutrophil number and serum TNF levels were predictors for conversion to acute leukaemia. The frequent occurrence of infections, on the other hand, could be better predicted by the absolute numbers of neutrophils and CD4+ cells and by the skin test score.

Aged↗
PubMed1991

Biological and biochemical characterization of a factor produced spontaneously by adherent cells of human immunodeficiency virus-infected patients inhibiting interleukin-2 receptor alpha chain (Tac) expression on normal T cells.

Adherent cells from human immunodeficiency virus (HIV)-infected subjects but not from normal blood donors, patients with Gram-positive or -negative bacteremia, active tuberculosis, toxoplasmosis, pulmonary aspergillosis, and cytomegalovirus infection produce spontaneously an activity which inhibits alpha chain of interleukin-2 (Tac) expression and interleukin 2 (IL-2) production by normal activated T cells and IL-2 production by these cells. A similar biologic activity was detected in culture supernatants of in vitro HIV-I-infected normal adherent and leukemic U937 cells. Tac-inhibitory activity is not cytotoxic and it could be detected in serum-free conditioned media. Recombinant granulocyte/macrophage colony-stimulating factor and phorbol myristate acetate stimulation of patients' and normal adherent cells did not enhance specifically the production of the Tac inhibitor. Biologically active conditioned media did not contain infectious virus as well as secreted p24, gp120 viral proteins; the biologic activity could not be abolished by anti-p24, anti-gp120, and anti-nef monoclonal antibodies or human purified polyclonal anti-HIV IgG. Gel filtration of conditioned media followed by anion exchange chromatography resulted in a 1,200-fold degree of purification and revealed that the biologically active molecule was cationic. Sodium dodecyl sulfate polyacrylamide gel electrophoresis of this fraction and gel elution of the proteins showed that the biologic activity was associated with a 29-kD protein which was distinct from alpha- or gamma-interferon, tumor necrosis factor-alpha, and prostaglandin E2. The above findings demonstrate the production of inhibitory factor(s) during HIV infection, which might be involved in the pathogenesis of the patients' immune defect.

Cell Adhesion↗
PubMed1991

Production of a tac inhibitory activity by adherent cells of HIV-infected subjects at different clinical stages.

Studying the mechanisms of the impaired T-cell colony growth from HIV-infected subjects, we have demonstrated that depletion of adherent cells from some patients' peripheral blood mononuclear cells enhanced the plating efficiency of T colony-forming cells. We report here that media conditioned by patients' cells but not normal adherent cells could inhibit the expression of the interleukin-2 receptor alpha (IL-2R alpha) chain but not the IL-2R beta chain in a dose-dependent manner. This inhibitory activity was produced by macrophage-monocyte cells since they displayed the My9+ My7+ OKM1+ phenotype and since adherent cell depletion by complement-mediated cytotoxicity with the My9 monoclonal antibody completely abrogated production of the inhibitory activity. A similar inhibitory activity, which could not be recognized by anti-p24 or anti-gp 120 monoclonal antibody or purified human anti-HIV immun]gobulin G in Western blot assays, could also be detected in culture supernatants of in vitro HIV-infected normal adherent and U937 leukemic cells. Production of IL-2R alpha chain inhibitory activity was associated with a decreased mitogen-induced expression of IL-2R alpha chain on patients' PBMC in 8 of 10 studied cases. Its production could be detected in 82, 58, and 91% of media conditioned by adherent cells from stage II, III, and IV patients, respectively. The amount of IL-2R alpha chain inhibitor released by patients' adherent cells increased during the deterioration of the patients' clinical status, and zidovudine treatment completely abrogated its production in all patients. These findings strongly suggest that production of IL-2R alpha chain inhibitory activity is involved in the pathophysiology of the impaired T-cell responses during HIV infection and could be of clinical relevance during the patients' follow-up.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Autocrine growth of leukemic cells.

Autocrine growth is a process whereby a cell both secretes and responds to a growth factor. This paper describes the stepwise malignant progression of leukemic cells which has been demonstrated in many experimental models of autocrine leukemic growth. In contrast, autocrine growth has not been proven as a major physiopathological mechanism for the growth of leukemic cells in vivo in human myeloid and lymphocytic leukemias. Growth-factor independency of human leukemic cell lines may be due to clonal selection.

Cell Division↗
PubMed1990

The role of growth-factor receptors (excluding IL-2 receptors) in the proliferation and differentiation of normal and leukemic hematopoietic cells.

Receptors (R) are considered as allosteric enzymes whose action on metabolic chains is modulated through binding to the ligand. They play an essential role in the transduction of the multiple signals (e.g. interleukins or CSF) which intervene in the regulation of hematopoiesis. Their ordered interactions are necessary to regulate the growth and differentiation of normal hematopoietic precursors. This paper summarizes recent data concerning the structure-action relationship of growth-factor receptors in the signal transduction and alterations of growth-factor receptors which may play an important role in leukemic transformation. Some therapeutic modulations of growth-factors cascades are also discussed.

Cell Differentiation↗
PubMed1990

Interleukin 2 receptors.

Interleukin 2 receptors (IL-2-R) are composed of (at least) two chains: the alpha chain (or p55 or Tac) and the beta chain (or p70 or p75). The association of both chains constitutes high affinity IL2-R complexes (Kd congruent to 10-100 pM), whereas the alpha-chain or the beta chain alone bind IL-2 with low (Kd congruent to 5-50 nM) and intermediate (Kd congruent to 1 nM) affinities, respectively. The beta chain (but not the alpha chain) mediates IL-2 internalization and signal transduction (proliferation or differentiation) to the cell, thus only high and intermediate affinity IL-2-R are functional. High affinity IL-2-R are expressed on activated normal and leukemic T and B lymphoid cells. Low affinity IL-2-R (Tac alone) are seen on stimulated T cells, B cells, and monocytes, as well as on various leukemic cells. The p70 chain alone is constitutively expressed by subsets of normal resting T and B cells, LGL and NK cells and we have recently demonstrated its presence on leukemic cells from various hemopoietic lineages. The finding of IL-2-R on non-lymphoid cells may disclose new functions for IL-2.

B-Lymphocytes↗
PubMed1990

Phorbol myristate acetate induces both high affinity and low affinity interleukin 2-receptors on a pre-B leukemic cell line.

The human pre-B leukemic cell line Reh6 does not constitutively express the Tac molecule (p55), which is one of the two polypeptide chains of the interleukin 2-receptor (IL2-R). Cell incubation with Phorbol Myristate Acetate (PMA) induces expression of the Tac molecule in a dose and time-dependent manner. Binding experiments with radiolabelled recombinant IL2 (rIL2) revealed both high and low affinity IL2-R (225 +/- 105 sites/cell with a Kd of 130 +/- 51 pM and 24060 sites/cell with a Kd of 17.3 nM respectively), whereas unstimulated Reh6 cells only expressed intermediate affinity Reh6 cells revealed the presence of two polypeptide chains of mol. wts 55,000 (Tac molecule) and 70,000, as in normal activated T cells, while the 70,000 mol. wt chain alone was observed in unstimulated Reh6 cells. IL2-R-bearing Reh6 cells could absorb rIL2 in a dose-dependent manner and this absorption was inhibited by a monoclonal antibody against the Tac molecule (anti-Tac). Moreover, partial internalization of IL2 bound under high affinity conditions occurred at 37 degrees C. IL2-R expressed on PMA-induced cells were functional since rIL2 specifically enhanced the proliferation in vitro of PMA-treated cells in semi-solid but not liquid cultures. These findings thus demonstrate an IL2-dependent mechanism of proliferation in vitro of pre-B leukemic cells induced by PMA, which can express high affinity, functional IL2-R.

Cell Division↗
PubMed1990

Triethyllead-induced inhibition of proliferation of normal human lymphocytes through decreased expression of the Tac chain of interleukin 2 receptor.

Triethyllead (Et3Pb+) in concentrations 10(-5) to 10(-6) M has been shown to inhibit several key cellular molecular systems. In order to evaluate the effect of Et3Pb+ on the human immune system, the mitogen-induced cell proliferation of peripheral blood mononuclear cells was studied in the presence of Et3Pb+. Preincubation of normal T-lymphocytes with 10(-6) M Et3Pb+ for 1-4 h, which has been shown to be non-cytotoxic, was sufficient to inhibit subsequent mitogenic-induced cell growth. The Et3Pb(+)-induced impairement of the in vitro proliferation of mitogen-activated normal T-cells was due to a dose-dependent decreased expression of the p55 polypeptide chain (Tac molecule) of the interleukin-2 receptor (IL-2-R), which could not be enhanced by exogeneously added recombinant interleukin 2 (rIL-2). Conversely, the same concentrations of Et3Pb+ could not inhibit the mitogen-induced expression of MHC class II molecules and the transferin receptor on activated T-cells. The impaired membrane expression of p55 on T-cells induced by Et3Pb+ was due to a decrease of Tac mRNA transcripts as showed by Northern blot analysis. This effect seems to be specific since in parallel experiments Et3Pb+ could not inhibit both the accumulation of actin mRNA and the production of IL-2 by Et3Pb(+)-treated mitogen-activated cells. The effect of this organolead compound was also associated with a dose-dependent decrease of the Na(+)-K(+)-ATPase activity of normal lymphocytes. These results indicate that Et3Pb+ could affect specifically T-cell proliferative responses through an imbalance of the IL-2/IL-2-R system.

Blotting, Northern↗
PubMed1990

Defective uptake of alpha-fetoprotein (AFP) and transferrin (Tf) by PHA-activated peripheral blood lymphocytes from patients with AIDS and related syndromes.

Serum alpha-fetoprotein (AFP) and transferrin (Tf) are actively endocytosed by many growing cells during ontogenic and neoplastic growth, but also by peripheral T lymphocytes upon mitogen activation. AFP and Tf uptake occurs through receptor-mediated endocytosis. The purpose of the present work was to assess whether the expression and functional activity of AFP and Tf receptors are impaired in mitogen-activated T cells from several groups of HIV-1 seropositive (HIV+) individuals. Forty HIV+ cases were studied, including 12 patients with AIDS, 12 with lymphoadenopathy syndrome (LAS), as well as 16 asymptomatic homosexuals (As). Quantification of AFP and Tf uptake was carried out by fluorescence-activated cell sorting (FACS) using fluoresceinated derivatives of these proteins. Compared with healthy blood donors, the three HIV-1 seropositive groups exhibited clear impairment in the ability of their peripheral blood mononuclear cells (PBMC) to internalize AFP and Tf. The decrease in mean values of AFP uptake correlates roughly with the severity of the clinical status. Although these observations need to be confirmed after a much wider study groups, the AFP-Tf-endocytosis assay presented here clearly reveals early defective functions of mitogen-responsive T cells in disease-free subjects and may provide the basis for a prognostic test. The pathophysiological implications of these facts are discussed in relation to the structural and/or metabolic activities of fatty acids and iron, the ligands carried by AFP and Tf, respectively.

AIDS-Related Complex↗
PubMed1990

Effect of phorbol myristate acetate on T cell colony formation, interleukin-2 (IL-2) receptor expression and IL-2 production by cells from patients at all stages of HIV infection.

We and others have shown that several T cell responses induced by the mitogen phytohaemagglutinin (PHA), including T cell colony formation, IL-2 receptor (IL-2R) expression, and IL-2 production are impaired in patients with AIDS and lymphadenopathy syndrome (LAS). We investigated whether phorbol myristate acetate (PMA) could act in synergy with PHA (as it does in healthy subjects) to enhance in vitro T cell responses of patients at all stages of infection by HIV. In AIDS patients with opportunistic infections (AIDS/OI), PHA + IL-2 + PMA led to a total disappearance of T cell colonies in 10/11 patients, among whom six already displayed very low numbers of colonies induced by PHA + IL-2 (less than 50 colonies/5 x 10(4) cells). In contrast, T cell colony formation induced by PHA + IL-2 + PMA was maintained or increased, compared with that induced by PHA + IL-2, in five out of six AIDS patients with Kaposi's sarcoma (AIDS/KS), 10/14 LAS and six out of seven HIV-seropositive asymptomatic (HIV+/AS) homosexuals. In these three groups of patients, a low percentage of colony cells induced by PHA + IL-2 + PMA expressed CD3 and CD4 molecules, but 50-89% of cells were IL-2R (Tac) positive, as in healthy controls. Studies on T cell activation and IL-2 production were performed on a selected group of 12 HIV-infected patients for whom sufficient numbers of lymphocytes could be obtained. PMA induced CD4 down-modulation in controls and in HIV-infected patients. However, CD3 down-modulation and induction of the Tac chain of IL-2R by PMA were significantly impaired in patients, compared with controls, and these two parameters were correlated. Although PHA alone induced virtually normal levels of Tac antigen on patients' cells, Tac induction by PHA + PMA was significantly decreased in patients versus controls. Cells from five out of 10 patients tested failed to produce detectable amounts of IL-2 after PHA stimulation, whereas IL-2 production increased significantly in all patients tested (n = 9) after PHA + PMA, with a level of IL-2 activity significantly higher than in controls. No correlation was found in this group of patients between the effects of PMA + PHA on T cell colony formation, Tac expression, or IL-2 production, as compared with PHA alone. Taken together, our results indicate that in vitro T cell functional studies with PMA may be useful to evaluate better the defects of T cell activation in HIV-infected patients.

Antigens, CD↗
PubMed1990

Seroprevalence of HIV-2 infection in Greece (Crete).

The seroprevalence of HIV-2 was evaluated in 20,407 consecutive normal blood donors, 100 homo- and/or bisexuals, and 7,020 heterosexuals presenting for an HIV test using an EIA test. Sixty-seven sera were revealed to be repeatedly positive. Analysis by Western blot confirmed the infection in four cases, an indeterminate (antibodies against only the gag-encoded proteins) pattern was revealed in 25 cases, whereas 38 sera were negative. Three of the four HIV-2-positive sera also reacted with two distinct, but close, synthetic peptides homologous to viral gp36. The fourth serum, which did not display antibodies against gp36 on Western blot, did not react with gp36-derived synthetic peptides. None of these sera reacted with native HIV-1 antigens or synthetic peptides homologous to gp41. Sera with an indeterminate HIV-2 Western blot did not react with gp36-derived synthetic peptides. Although 10 of them also displayed an indeterminate HIV-1 Western blot, no serum sample reacted with two gp41-derived synthetic peptides or proved to be positive when they tested for p24 antigen. One bisexual and one heterosexual HIV-2 positive subject reported sexual contacts with West Africans, whereas two other heterosexuals had had multiple sexual partners from different countries.

Acquired Immunodeficiency Syndrome↗