scholarly journals Mycobacterium avium-intracellulare induces interleukin-6 from human monocytes and large granular lymphocytes

Blood ◽  
1991 ◽  
Vol 77 (10) ◽  
pp. 2218-2224 ◽  
Author(s):  
DK Blanchard ◽  
MB Michelini-Norris ◽  
CA Pearson ◽  
CS Freitag ◽  
JY Djeu
Keyword(s):  
T Cells ◽  
Mycobacterium Avium ◽  
Interleukin 6 ◽  
Mononuclear Cells ◽  
Human Leukocyte ◽  
Large Granular Lymphocytes ◽  
Peripheral Blood Mononuclear ◽  
Mycobacterium Avium Intracellulare ◽  
Culture Supernatants ◽  
Granular Lymphocytes

Abstract Mycobacterium avium-intracellulare (MAI) is an opportunistic pathogen commonly found in acquired immunodeficiency syndrome patients, whose immune systems are severely compromised. However, normal responses to this bacterium are apparently sufficient to prevent disseminated infection because disease is rarely found unless an immunocompromised state is present. Because interleukin-6 (IL-6) is an inflammatory cytokine with a multitude of activities, we investigated the potential of MAI to induce IL-6 from normal human leukocytes. Peripheral blood mononuclear cells were fractionated into monocytes (Mo), large granular lymphocytes (LGL), and T cells and stimulated with bacteria. Culture supernatants were collected and assayed for IL-6 activity by bioassay. Mo and LGL, but not T cells, were found to release IL-6 within 12 hours of stimulation, with optimal production occurring by 2 days of culture. Production of IL-6 from human leukocyte subsets was confirmed by Northern blot analysis and by neutralization of biologic function of the culture supernatants with specific antisera. Taken together, these results indicate that production of IL-6 is a key response of Mo and LGL to MAI. The role of IL-6 in MAI infection, therefore, needs to be further investigated.

scholarly journals Mycobacterium avium-intracellulare induces interleukin-6 from human monocytes and large granular lymphocytes

Blood ◽  
1991 ◽  
Vol 77 (10) ◽  
pp. 2218-2224
Author(s):  
DK Blanchard ◽  
MB Michelini-Norris ◽  
CA Pearson ◽  
CS Freitag ◽  
JY Djeu
Keyword(s):  
T Cells ◽  
Mycobacterium Avium ◽  
Interleukin 6 ◽  
Mononuclear Cells ◽  
Human Leukocyte ◽  
Large Granular Lymphocytes ◽  
Peripheral Blood Mononuclear ◽  
Mycobacterium Avium Intracellulare ◽  
Culture Supernatants ◽  
Granular Lymphocytes

Mycobacterium avium-intracellulare (MAI) is an opportunistic pathogen commonly found in acquired immunodeficiency syndrome patients, whose immune systems are severely compromised. However, normal responses to this bacterium are apparently sufficient to prevent disseminated infection because disease is rarely found unless an immunocompromised state is present. Because interleukin-6 (IL-6) is an inflammatory cytokine with a multitude of activities, we investigated the potential of MAI to induce IL-6 from normal human leukocytes. Peripheral blood mononuclear cells were fractionated into monocytes (Mo), large granular lymphocytes (LGL), and T cells and stimulated with bacteria. Culture supernatants were collected and assayed for IL-6 activity by bioassay. Mo and LGL, but not T cells, were found to release IL-6 within 12 hours of stimulation, with optimal production occurring by 2 days of culture. Production of IL-6 from human leukocyte subsets was confirmed by Northern blot analysis and by neutralization of biologic function of the culture supernatants with specific antisera. Taken together, these results indicate that production of IL-6 is a key response of Mo and LGL to MAI. The role of IL-6 in MAI infection, therefore, needs to be further investigated.

scholarly journals Large granular lymphocytes have a promoting activity on human peripheral blood erythroid burst-forming units

Blood ◽  
1985 ◽  
Vol 65 (2) ◽  
pp. 464-472 ◽  
Author(s):  
V Pistoia ◽  
R Ghio ◽  
A Nocera ◽  
A Leprini ◽  
A Perata ◽  
...  
Keyword(s):  
Peripheral Blood ◽  
Colony Formation ◽  
Mononuclear Cells ◽  
Human Peripheral Blood ◽  
Accessory Cell ◽  
Surface Markers ◽  
Large Granular Lymphocytes ◽  
Peripheral Blood Mononuclear ◽  
Hla Dr ◽  
Granular Lymphocytes

Abstract Peripheral blood mononuclear cells were fractionated according to the expression of a variety of surface markers, and the fractions obtained were tested for erythroid burst-forming unit (BFU-E) colony formation. BFU-Es were detected in the HLA-DR+ non-T cell fraction, but gave rise to optimum colony numbers only in the presence of a nonadherent, relatively radioresistant cell. This accessory cell was found among the HLA-DR- non-T, non-B cells, a fraction that was particularly enriched in large granular lymphocytes (LGLs). Experiments carried out to assess directly the surface markers of the accessory cell revealed an FcR+, OKM1+, Leu 7+, Leu 11+, OKT4-, OKT8- surface phenotype, which is consistent with that of the majority of LGLs. Peripheral blood LGLs, purified by Percoll density gradient, proved very efficient in promoting optimal BFU-E colony formation. All of these results indicate that LGLs have a potent erythroid burst-promoting activity. Such activity is probably mediated through the release of soluble factors, as shown by the observation that LGL culture supernatants were as effective as LGLs in sustaining colony formation.

scholarly journals Role of Capsule and Interleukin-6 in Long-Term Immune Control of Cryptococcus neoformans Infection by Specifically Activated Human Peripheral Blood Mononuclear Cells

2006 ◽  
Vol 74 (9) ◽  
pp. 5302-5310 ◽  
Author(s):  
Asna A. Siddiqui ◽  
Robin J. Shattock ◽  
Thomas S. Harrison
Keyword(s):  
Immune Response ◽  
T Cells ◽  
Peripheral Blood Mononuclear Cells ◽  
Interleukin 6 ◽  
Peripheral Blood ◽  
Mononuclear Cells ◽  
Immune Control ◽  
Peripheral Blood Mononuclear ◽  
Blood Mononuclear Cells

ABSTRACT Cryptococcus neoformans is a frequent cause of meningoencephalitis in immunosuppressed individuals. To better understand the mechanisms of a protective immune response to C. neoformans, a long-term in vitro model of human immune control of cryptococcal infection was developed. Peripheral blood mononuclear cells (PBMC) prestimulated with heat-killed C. neoformans significantly restricted the growth of C. neoformans after a subsequent live infection compared to that with unstimulated PBMC. Live infection with encapsulated C. neoformans was controlled for as long as 10 days, while infection with acapsular organisms could sometimes be eradicated. During immune control, fungal cells were both intracellular and extracellular within aggregates of mononuclear phagocytes and lymphocytes. Optimal immune control depended on the presence of both CD4+ and CD8+ T cells. Immune control of cryptococcal growth was more effective following prestimulation with acapsular compared with encapsulated organisms. Prestimulation with acapsular organisms was associated with a significant and prolonged increase in interleukin-6 (IL-6) production compared with prestimulation with encapsulated C. neoformans. Addition of IL-6 and depletion of CD25+ T cells prior to prestimulation and infection with encapsulated organisms resulted in reductions in cryptococcal growth that reached borderline statistical significance. Depletion of CD25+ T cells significantly reduced cryptococcal growth in wells with unstimulated PBMC. The results demonstrate an association between high levels of IL-6 and resistance to infection and, through suppression of IL-6 release, an additional mechanism whereby the cryptococcal capsule subverts a protective immune response. Further work is required to clarify the mechanism of action of IL-6 in this setting and any interaction with regulatory T cells.

scholarly journals Neutralization of Interleukin-10 from CD14+ Monocytes Enhances Gamma Interferon Production in Peripheral Blood Mononuclear Cells from Mycobacterium avium subsp. paratuberculosis-Infected Goats

2009 ◽  
Vol 16 (7) ◽  
pp. 1003-1011 ◽  
Author(s):  
Kari R. Lybeck ◽  
Anne K. Storset ◽  
Ingrid Olsen
Keyword(s):  
T Cells ◽  
Mycobacterium Avium ◽  
Mononuclear Cells ◽  
Cell Receptor ◽  
Interleukin 10 ◽  
Gamma Interferon ◽  
Regulatory Mechanisms ◽  
Interferon Production ◽  
Peripheral Blood Mononuclear

ABSTRACT The gamma interferon assay is used to identify Mycobacterium avium subsp. paratuberculosis-infected animals. It has been suggested that regulatory mechanisms could influence the sensitivity of the test when it is performed with cells from cattle and that the neutralization of interleukin-10 (IL-10) in vitro would increase the gamma interferon responses. To investigate the regulatory mechanisms affecting the gamma interferon assay with cells from goats, blood was collected from M. avium subsp. paratuberculosis-infected, M. avium subsp. paratuberculosis-exposed, and noninfected goats. Neutralization of IL-10 by a monoclonal antibody resulted in increased levels of gamma interferon production in M. avium subsp. paratuberculosis purified protein derivative (PPDj)-stimulated samples from both infected and exposed goats. However, the levels of gamma interferon release were also increased in unstimulated cells and in PPDj-stimulated cells from some noninfected animals following neutralization. Depletion of putative regulatory CD25high T cells had no clear effect on the number of gamma-interferon-producing cells. The IL-10-producing cells were identified to be mainly CD14+ major histocompatibility complex class II-positive monocytes in both PPDj-stimulated and control cultures and not regulatory T cells. However, possible regulatory CD4+ CD25+ T cells produced IL-10 in response to concanavalin A stimulation. The numbers of CD4+, CD8+, and CD8+ γδT-cell receptor-positive cells producing gamma interferon increased following IL-10 neutralization. These results provide insight into the source and the role of IL-10 in gamma interferon assays with cells from goats and suggest that IL-10 from monocytes can regulate both innate and adaptive gamma interferon production from several cell types. Although IL-10 neutralization increased the sensitivity of the gamma interferon assay, the specificity of the test could be compromised.

scholarly journals Ex Vivo Generation of Donor Antigen-Specific Immunomodulatory Cells

2018 ◽  
Vol 27 (11) ◽  
pp. 1692-1704
Author(s):  
M. Watanabe ◽  
Makiko Kumagai-Braesch ◽  
M. Yao ◽  
S. Thunberg ◽  
D. Berglund ◽  
...  
Keyword(s):  
T Cells ◽  
Mononuclear Cells ◽  
Ex Vivo ◽  
Human Peripheral Blood ◽  
Human Leukocyte ◽  
Interleukin 10 ◽  
Control Group ◽  
Peripheral Blood Mononuclear ◽  
Foxp3 Mrna ◽  
Ifn Γ

Adoptive transfer of alloantigen-specific immunomodulatory cells generated ex vivo with anti-CD80/CD86 mAbs (2D10.4/IT2.2) holds promise for operational tolerance after transplantation. However, good manufacturing practice is required to allow widespread clinical application. Belatacept, a clinically approved cytotoxic T-lymphocyte antigen 4-immunoglobulin that also binds CD80/CD86, could be an alternative agent for 2D10.4/IT2.2. With the goal of generating an optimal cell treatment with clinically approved reagents, we evaluated the donor-specific immunomodulatory effects of belatacept- and 2D10.4/IT2.2-generated immunomodulatory cells. Immunomodulatory cells were generated by coculturing responder human peripheral blood mononuclear cells (PBMCs) (50 × 106 cells) with irradiated donor PBMCs (20 × 106 cells) from eight human leukocyte antigen-mismatched responder–donor pairs in the presence of either 2D10.4/IT2.2 (3 μg/106 cells) or belatacept (40 μg/106 cells). After 14 days of coculture, the frequencies of CD4+ T cells, CD8+ T cells, and natural killer cells as well as interferon gamma (IFN-γ) production in the 2D10.4/IT2.2- and belatacept-treated groups were lower than those in the control group. The percentage of CD19+ B cells was higher in the 2D10.4/IT2.2- and belatacept-treated groups than in the control group. The frequency of CD4+CD25+CD127lowFOXP3+ T cells increased from 4.1±1.0% (preculture) to 7.1±2.6% and 7.3±2.6% (day 14) in the 2D10.4/IT2.2- and belatacept-treated groups, respectively ( p<0.05). Concurrently, delta-2 FOXP3 mRNA expression increased significantly. Compared with cells derived from the no-antibody treated control group, cells generated from both the 2D10.4/IT2.2- and belatacept-treated groups produced lower IFN-γ and higher interleukin-10 levels in response to donor-antigens, as detected by enzyme-linked immunospot. Most importantly, 2D10.4/IT2.2- and belatacept-generated cells effectively impeded the proliferative responses of freshly isolated responder PBMCs against donor-antigens. Our results indicate that belatacept-generated donor-specific immunomodulatory cells possess comparable phenotypes and immunomodulatory efficacies to those generated with 2D10.4/IT2.2. We suggest that belatacept could be used for ex vivo generation of clinical grade alloantigen-specific immunomodulatory cells for tolerance induction after transplantation.

scholarly journals Activation signals leading to proliferation of normal and leukemic CD3+ large granular lymphocytes

Blood ◽  
1991 ◽  
Vol 78 (5) ◽  
pp. 1282-1285 ◽  
Author(s):  
JA Aprile ◽  
M Russo ◽  
MS Pepe ◽  
TP Jr Loughran
Keyword(s):  
Cell Cycle ◽  
Mononuclear Cells ◽  
Interleukin 2 ◽  
Cell Receptor ◽  
Interleukin 4 ◽  
Large Granular Lymphocytes ◽  
Peripheral Blood Mononuclear ◽  
Incorporation Assay ◽  
Granular Lymphocytes

Abstract The activation signals leading to proliferation of normal and leukemic CD3+ large granular lymphocytes (LGL) were studied in vitro. Anti-CD3 monoclonal antibody (MoAb) alone (P less than .01) and recombinant interleukin-2 (IL-2) alone (P less than .01) caused significant stimulation of peripheral blood mononuclear cells (PBMC) from four CD3+ LGL leukemia patients, as measured in a 3H-thymidine incorporation assay. Recombinant interleukin-4 (IL-4) alone had no effect (P = .11). The combination signals of anti-CD3 MoAb and either IL-2 or IL-4 produced a proliferative response greater than anti-CD3 MoAb alone (P less than .01) or lymphokine alone (P less than .01). Leukemic LGL, purified by two-color sorting, were subsequently activated by anti-CD3 MoAb and IL-2 and assessed for DNA content by viable Hoechst No. 33342 (HO) staining. Results of these studies demonstrated that leukemic LGL were stimulated directly by anti-CD3 MoAb and IL-2, with the percentage of cells in cell cycle (S + G2/M) ranging from 16% to 72%. Normal CD3+ LGL were also stimulated to enter the cell cycle by anti-CD3 and IL-2. These results show that leukemic LGL proliferate in vitro after activation through the T-cell receptor and/or lymphokine.

scholarly journals Induction of interleukin-6 during human immunodeficiency virus infection

Blood ◽  
1990 ◽  
Vol 76 (11) ◽  
pp. 2303-2310 ◽  
Author(s):  
DL Birx ◽  
RR Redfield ◽  
K Tencer ◽  
A Fowler ◽  
DS Burke ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
T Cells ◽  
Interleukin 6 ◽  
Mononuclear Cells ◽  
Elevated Serum ◽  
Peripheral Blood Mononuclear ◽  
Immunodeficiency Virus ◽  
Normal Monocyte ◽  
Hiv Seropositive

Interleukin-6 (IL-6), a multifunctional cytokine produced in monocytes, fibroblasts, and other cell types, is induced by a variety of stimuli, including bacteria, viruses, and other cytokines. When normal monocyte cultures were exposed to a monocytotropic strain of human immunodeficiency virus (HIV), HTLV-IIIBa-L, significant levels of IL-6 bioactivity were detected in the culture supernatants after 12 to 43 days of incubation, at a time when there was associated evidence of HIV production. Similarly, when normal monocyte cultures were cocultured with peripheral blood mononuclear cells from HIV-infected individuals, HIV replication in these cultures was associated with production of IL- 6. In further studies, we determined that mean serum levels of IL-6 bioactivity were abnormally elevated in HIV-seropositive individuals with stage 1/2 infection (25.2 x/divided by 1.8 U/mL) and stage 3/4 infection (46.1 x/divided by 1.7 U/mL) when compared with normals (1.6 x/divided by 1.2 U/mL). In contrast mean serum IL-6 levels were not different from normal in stage 5/6 infection (2.7 x/divided by 1.6 U/mL). A selected group of 12 HIV-seropositive individuals (stages 1, 2, and 3) who harbored HIV capable of replicating in T cells but not in monocyte cultures had a mean serum IL-6 level of 5.3 U/mL (x/divided by 1.5), a value significantly lower (P less than .004) than that measured in control HIV-seropositive individuals infected with monocytropic HIV (39 x/divided by 1.9 U/mL). In addition, serum IL-6 levels in HIV- seropositive individuals (stages 1 through 6) correlated directly with serum immunoglobulin G (IgG) levels (R = .74, P less than .001). Monocytes but not T cells are capable of a high level IL-6 production in vitro, and monocyte-derived IL-6 stimulates Ig production in activated B cells. Thus, HIV-seropositive individuals who often are infected with monocytotropic HIV and often display abnormally elevated serum IgG levels may exhibit these abnormalities as a consequence of abnormally elevated IL-6 levels induced by HIV.

scholarly journals Graft failure after T-cell-depleted human leukocyte antigen identical marrow transplants for leukemia: II. In vitro analyses of host effector mechanisms

Blood ◽  
1989 ◽  
Vol 74 (6) ◽  
pp. 2237-2243 ◽  
Author(s):  
C Bordignon ◽  
CA Keever ◽  
TN Small ◽  
N Flomenberg ◽  
B Dupont ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Graft Failure ◽  
Mononuclear Cells ◽  
Human Leukocyte ◽  
Antigen Expression ◽  
Target Cells ◽  
Peripheral Blood Mononuclear ◽  
Surface Antigen Expression

To identify mechanisms potentially contributing to graft failure, 19 leukemic recipients of T-cell-depleted marrow transplants who failed to engraft following a transplant of HLA identical sibling marrow depleted of T cells by soybean agglutinin (SBA) and sheep erythrocytes (E) were evaluated. Peripheral blood mononuclear cells isolated at the time of failure were consistently of host origin, bearing the phenotype of suppressor T cells (CD3+, CD8+, Leu 7+). A direct cytolytic effect on 51Cr-labeled donor-derived target cells was not detected, a finding that contrasts with the donor-specific cytotoxic host T lymphocytes that have been regularly observed in patients rejecting HLA nonidentical SBA -E- BMTs. However, these host T cells did exhibit a strong and specific suppressive activity against the donor marrow CFU- GM in vitro. Furthermore, in contrast to prior findings in durably engrafted recipients of SBA -E- BMTs, the lymphocytes isolated prior to or at the time of graft failure lacked natural killer surface antigen expression and effector function.

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