Age-related changes in circannual rhythms of lymphocyte blastogenic responses in mice

1987 ◽  
Vol 252 (2) ◽  
pp. R299-R305
Author(s):  
M. A. Brock
Keyword(s):  
T Cells ◽  
Immune System ◽  
B Cells ◽  
B Lymphocytes ◽  
B Lymphocyte ◽  
Tritiated Thymidine ◽  
Age Related ◽  
Dividing Cells ◽  
Age Related Changes

Blastogenic responses to T- and B-lymphocyte mitogens were tested in suspensions of splenocytes from 15- and 24- to 28-mo-old C57BL/6 mice and compared with analogous responses in young animals. The mice were housed under constant environmental conditions with alternating light-dark cycles (LD 12:12). Single cell suspensions were cultured in vitro with mitogens, and the induced incorporation of tritiated thymidine by dividing cells was determined. Increases in periodicity of responses to concanavalin A and phytohemagglutinin by T cells and to lipopolysaccharide by B cells and lower mean levels of activation characterized rhythms in cells from 15-mo-old and senescent mice compared with young animals. Amplitudes of the rhythms were unchanged at 15 mo, but by 24 mo of age rhythmic responses of T but not B cells were damped. The separable effects of age on expression of circannual rhythms by T and B lymphocytes suggest another mechanism for imbalance in the immune system. Phases of depressed responses that are extended for several months in populations of older mice could provide increased opportunities for environmental assaults.

scholarly journals INTERACTION OF HUMAN THYMUS-DERIVED AND NON-THYMUS-DERIVED LYMPHOCYTES IN VITRO

1973 ◽  
Vol 138 (5) ◽  
pp. 1230-1247 ◽  
Author(s):  
Raif S. Geha ◽  
Eveline Schneeberger ◽  
Fred S. Rosen ◽  
Ezio Merler
Keyword(s):  
T Cells ◽  
B Cells ◽  
B Lymphocytes ◽  
Tetanus Toxoid ◽  
B Lymphocyte ◽  
De Novo ◽  
Gradient Centrifugation ◽  
Blast Transformation ◽  
Normal Individuals

Relatively pure populations of human T and B lymphocytes were obtained from blood and tonsils using density gradient centrifugation in bovine serum albumin. Antigen alone was incapable of triggering the B lymphocyte into blast transformation or to secrete antibody. However, supernatants from tetanus toxoid-stimulated T cells obtained from immune donors contained a factor mitogenic for B lymphocytes. 50–60% of B cells responded to this lymphocyte mitogenic factor (LMF) by proliferation, loss of C3 reactivity, and change to a secretory state. LMF-stimulated B cells exhibited a three- to fivefold increase in protein secretion and a six- to eightfold increase in gamma G globulin secretion. De novo secreted IgG had specificity directed to the tetanus toxoid present in the LMF containing T-cell supernatants. This was confirmed by an increase in the number of indirect plaque-forming cells to tetanus toxoid-coated sheep red blood cells after stimulation of B cells with LMF. It is proposed that in the course of the response to a previously encountered protein antigen, sensitized human T cells emit a signal in the form of a soluble product that, together with antigen, triggers B cells into division and antibody secretion. The experimental model utilized can be adapted to study human T-B cell cooperation under various conditions in normal individuals and in individuals with immunodeficiency diseases.

scholarly journals Autologous stimulation of human lymphocyte subpopulation.

1975 ◽  
Vol 142 (5) ◽  
pp. 1327-1333 ◽  
Author(s):  
G Opelz ◽  
M Kiuchi ◽  
M Takasugi ◽  
P I Terasaki
Keyword(s):  
T Cells ◽  
B Cells ◽  
B Lymphocytes ◽  
Human Lymphocyte ◽  
Lymphocyte Subpopulation ◽  
High Background ◽  
Background Stimulation ◽  
Most Probable Explanation ◽  
Stimulation Of

The background stimulation universally seen when lymphocytes are cultured in vitro has been shown to be markedly lowered by reducing the proportion of B lymphocytes. B-rich fractions of lymphocytes had extremely high background stimulation. It is concluded that stimulation of T cells, probably by autologous B cells, provides the most probable explanation for the findings described.

scholarly journals IgG subclass, IgE, and IgA anti-trinitrophenyl antibody production within trinitrophenyl-Ficoll-responsive B cell clones. Evidence in support of three distinct switching pathways.

1983 ◽  
Vol 157 (1) ◽  
pp. 69-85 ◽  
Author(s):  
P K Mongini ◽  
W E Paul ◽  
E S Metcalf
Keyword(s):  
T Cells ◽  
B Cells ◽  
B Cell ◽  
B Lymphocyte ◽  
Igg Subclasses ◽  
Igg Subclass ◽  
Cell Clones ◽  
High Propensity ◽  
Focus Assay

The IgM, IgG subclass, IgE, and IgA anti-trinitrophenyl (TNP) antibody (Ab) response of B cells to the type 2 antigen TNP-Ficoll was studied in athymic nude mice and in the in vitro splenic focus assay. Results from the splenic focus assay in which purified B lymphocyte preparations had been transferred to irradiated nu/nu recipients indicate that many TNP-Ficoll stimulated B cell clones secrete multiple isotypes and hence appear to be undergoing intraclonal isotype switching. Although the frequency of clones secreting each of the IgG subclasses was found to correlate with 5' to 3' Igh-gamma gene order, the frequency of IgE and IgA-secreting clones did not appear to be influenced by the respective position of Igh-epsilon and Igh-alpha on the chromosome. Unlike clones that secreted anti-TNP Ab of the IgG subclasses, IgE and IgA anti-TNP Ab-secreting clones did not have a high propensity for coexpression of isotypes encoded by 5' Igh-C genes. These data suggest that three distinct switching pathways may be employed by B cells responding to TNP-Ficoll: a common IgG pathway, an IgE pathway, and an IgA pathway. The presence of T cells resulted in a preferential enhancement of the production of anti-TNP Ab of those IgG subclasses which were least represented in the absence of T cells, i.e., IgG2b and IgG2a. No significant enhancement of IgE anti-TNP clonal frequency was found in the presence of T lymphocytes, but T cells were found to significantly enhance the clonal expression of IgA anti-TNP Ab. Although a relatively large number of B cell clones were found to synthesize IgE and IgA anti-TNP Ab in the splenic focus assay, relatively little or no secretion of these isotypes was detected in immune mice. Possible explanations for this apparent discrepancy are discussed.

scholarly journals B Lymphocyte Chemotaxis Regulated in Association with Microanatomic Localization, Differentiation State, and B Cell Receptor Engagement

1998 ◽  
Vol 187 (5) ◽  
pp. 753-762 ◽  
Author(s):  
Conrad C. Bleul ◽  
Joachim L. Schultze ◽  
Timothy A. Springer
Keyword(s):  
B Cells ◽  
B Cell ◽  
B Lymphocytes ◽  
Messenger Rna ◽  
B Lymphocyte ◽  
Somatic Hypermutation ◽  
Cell Receptor ◽  
B Cell Receptor ◽  
Cxc Chemokine

Migration of mature B lymphocytes within secondary lymphoid organs and recirculation between these sites are thought to allow B cells to obtain T cell help, to undergo somatic hypermutation, to differentiate into effector cells, and to home to sites of antibody production. The mechanisms that direct migration of B lymphocytes are unknown, but there is evidence that G protein–coupled receptors, and possibly chemokine receptors, may be involved. Stromal cell– derived factor (SDF)-1α is a CXC chemokine previously characterized as an efficacious chemoattractant for T lymphocytes and monocytes in peripheral blood. Here we show with purified tonsillar B cells that SDF-1α also attracts naive and memory, but not germinal center (GC) B lymphocytes. Furthermore, GC B cells could be converted to respond to SDF-1α by in vitro differentiation into memory B lymphocytes. Conversely, the migratory response in naive and memory B cells was significantly reduced after B cell receptor engagement and CD40 signaling. The receptor for SDF-1, CXC chemokine receptor 4 (CXCR4), was found to be expressed on responsive as well as unresponsive B cell subsets, but was more rapidly downregulated on responsive cells by ligand. Finally, messenger RNA for SDF-1 was detected by in situ hybridization in a layer of cells surrounding the GC. These findings show that responsiveness to the chemoattractant SDF-1α is regulated during B lymphocyte activation, and correlates with positioning of B lymphocytes within a secondary lymphoid organ.

scholarly journals The Influence of Aging and Sex Hormones on Expression of Growth Hormone-Releasing Hormone in the Human Immune System1

2001 ◽  
Vol 86 (7) ◽  
pp. 3157-3161
Author(s):  
O. Khorram ◽  
M. Garthwaite ◽  
T. Golos
Keyword(s):  
T Cells ◽  
Immune System ◽  
B Cells ◽  
Mrna Expression ◽  
Postmenopausal Women ◽  
Cell Line ◽  
Immune Cell ◽  
Hormone Replacement ◽  
Men And Women

GHRH is a neuropeptide that has also been localized to the immune system. The physiological function of GHRH in the immune system has not been elucidated. This study was conducted to determine whether immune GHRH expression is altered in certain pathological states, such as immune cell tumors, and whether gender, aging, and alterations in the sex steroid milieu influence the expression of this peptide in immune cells. Using double color flow cytometry, GHRH protein was found to be expressed in less than 2% of peripheral blood mononuclear cells (PBMC). Monocytes and B and T cells all expressed GHRH protein, although a greater percentage of T cells compared with B cells and monocytes expressed GHRH (5- to 7-fold). Semiquantitative RT-PCR was used to quantify GHRH messenger ribonucleic acid (mRNA) in PBMC and several immune cell-derived tumors. PBMC and granulocytes expressed low levels of GHRH mRNA with relatively higher levels of expression in monocytes. The tumor cell lines CEMX 174 (B/T cells), HUT 78 (T cells), WIL2-N (B cells), U937 (monocytes/macrophages), and JM 1 (pre-B cell lymphoma) all showed greater expression of GHRH mRNA relative to PBMC. However, two cell lines, CCRF-SB, a B lymphoblastoid cell line, and HL-60, a promyelocytic cell line, expressed GHRH mRNA at similar levels as PBMC. A significant decrease in the percentage of lymphocytes (CD45+ cells) expressing GHRH protein was found in age-advanced men and women compared with young men and women. This decline was noted in B cells (CD20+) and monocytes (CD14+), but not in T cells (CD3+). GHRH mRNA expression in PBMC derived from postmenopausal women was lower than that from premenopausal women. However, no differences in PBMC GHRH mRNA expression were found in young and old men. Although in older men there were fewer peripheral lymphocytes that express GHRH protein, these cells secreted significantly more GHRH in vitro than cells from postmenopausal women with no hormone replacement therapy (HRT), but similar levels as cells from women receiving HRT. PBMC from women receiving HRT secreted more GHRH in vitro than cells from women receiving no hormone replacement. This study demonstrates that the expression of immune GHRH is dynamic, and therefore likely to be regulated. Increased expression of GHRH in certain immune tumors suggests that GHRH may be mitogenic under certain conditions and therefore play a role in the pathogenesis of select immune cell tumors. Collectively, these results suggest a role for GHRH as a local immune modulator and in the pathophysiology of immunosenescence and immune cell tumors.

scholarly journals CELL INTERACTIONS IN THE IMMUNE RESPONSE IN VITRO

1972 ◽  
Vol 136 (4) ◽  
pp. 737-760 ◽  
Author(s):  
Marc Feldmann
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cells ◽  
B Cell ◽  
B Lymphocytes ◽  
Cell Interaction ◽  
T And B Lymphocytes ◽  
Activated T Cells ◽  
Cell Cooperation

The mechanism of interaction of T and B lymphocytes was investigated in an in vitro hapten carrier system using culture chambers with two compartments separated by a cell impermeable nucleopore membrane. Because specific cell interaction occurred efficiently across this membrane, contact of T and B lymphocytes was not essential for cooperation which must have been mediated by a subcellular component or "factor." By using different lymphoid cell populations in the lower culture chamber and activated thymus cells in the upper chamber (with antigen present in both), it was found that the antigen-specific mediator acted indirectly on B cells, through the agency of macrophages. Macrophages which had been cultured in the presence of activated T cells and antigen acquired the capacity to specifically induce antibody responses in B cell-containing lymphoid populations. Trypsinization of these macrophages inhibited their capacity to induce immune responses, indicating that the mediator of cell cooperation is membrane bound. By using antisera to both the haptenic and carrier determinants of the antigen as blocking reagents, it was demonstrated that the whole antigen molecule was present on the surface of macrophages which had been exposed to activated T cells and antigen. Because specifically activated T cells were essential a component of the antigen-specific mediator must be derived from these cells. By using anti-immunoglobulin sera as inhibitors of the binding of the mediator to macrophages, the T cell component was indeed found to contain both κ- and µ-chains and was thus presumably a T cell-derived immunoglobulin. It was proposed that cell cooperation is mediated by complexes of T cell IgM and antigen, bound to the surface of macrophage-like cells, forming a lattice of appropriately spaced antigenic determinants. B cells become immunized by interacting with this surface. With this mechanism of cell cooperation, the actual pattern of antigen-B cell receptor interactions in immunization would be the same with both thymus-dependent and independent antigens. An essential feature of the proposed mechanism of cell cooperation is that macrophage-B cell interaction must occur at an early stage of the antibody response, a concept which is supported by many lines of evidence. Furthermore this mechanism of cell interaction can be elaborated to explain certain phenomena such as the highly immunogenic macrophage-bound antigen, antigenic competition, the distinction between immunity and tolerance in B lymphocytes, and the possible mediation of tolerance by T lymphocytes.

scholarly journals Studies of in vitro activated CD5+ B cells

Blood ◽  
1989 ◽  
Vol 73 (1) ◽  
pp. 202-208 ◽  
Author(s):  
AS Freedman ◽  
G Freeman ◽  
J Whitman ◽  
J Segil ◽  
J Daley ◽  
...  
Keyword(s):  
B Cells ◽  
B Cell ◽  
B Lymphocytes ◽  
Cell Activation ◽  
Tritiated Thymidine ◽  
Interleukin 1 ◽  
Cell Subpopulation ◽  
Recombinant Interferon ◽  
Barr Virus

Abstract Human B lymphocytes undergo distinct phenotypic changes following activation with antigen and polyclonal mitogens. Increasing interest has focused on the unique subpopulation of B cells that expresses the CD5 antigen. In this study, we examined the signals that induce the expression of CD5 on normal splenic B cells. Only 12-O- tetradecanoylphorbol-13-acetate (TPA) induced CD5 expression on highly purified splenic B cells, whereas anti-immunoglobulin (anti-Ig), Epstein-Barr virus, anti-CD20, recombinant interleukin-1 (rIL-1), rIL- 2, rIL-4, recombinant interferon-gamma (rINF-gamma), and B-cell growth factor all failed to induce CD5 expression. The expression of CD5 was detected on the cell surface by 48 hours and decreased by 96 hours. Dual-fluorochrome analysis demonstrated that the CD5+ B cells coexpressed the B-cell activation antigens B5, IL-2 receptor, and CD23, thereby providing phenotypic evidence that this B-cell subpopulation is activated. In vitro studies of dual-fluorochrome-sorted, TPA-stimulated splenic B cells demonstrated significantly greater tritiated thymidine incorporation and Ig secretion by the CD20+ CD5- cells than by the CD20+ CD5+ subset. These phenotypic and functional studies are consistent with the notion that TPA-induced CD5+ B cells are a subset of in vitro activated B lymphocytes.

scholarly journals Immunoglobulin signal transduction guides the specificity of B cell-T cell interactions and is blocked in tolerant self-reactive B cells.

1994 ◽  
Vol 179 (2) ◽  
pp. 425-438 ◽  
Author(s):  
M P Cooke ◽  
A W Heath ◽  
K M Shokat ◽  
Y Zeng ◽  
F D Finkelman ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cells ◽  
Transgenic Mice ◽  
B Lymphocytes ◽  
Molecular Mechanisms ◽  
Interleukin 4 ◽  
Th Cells

The specificity of antibody (Ab) responses depends on focusing helper T (Th) lymphocyte signals to suitable B lymphocytes capable of binding foreign antigens (Ags), and away from nonspecific or self-reactive B cells. To investigate the molecular mechanisms that prevent the activation of self-reactive B lymphocytes, the activation requirements of B cells specific for the Ag hen egg lysozyme (HEL) obtained from immunoglobulin (Ig)-transgenic mice were compared with those of functionally tolerant B cells isolated from Ig-transgenic mice which also express soluble HEL. To eliminate the need for surface (s)Ig-mediated Ag uptake and presentation and allow the effects of sIg signaling to be studied in isolation, we assessed the ability of allogeneic T cells from bm12 strain mice to provide in vivo help to C57BL/6 strain-transgenic B cells. Interestingly, non-tolerant Ig-transgenic B cells required both allogeneic Th cells and binding of soluble HEL for efficient activation and Ab production. By contrast, tolerant self-reactive B cells from Ig/HEL double transgenic mice responded poorly to the same combination of allogeneic T cells and soluble HEL. The tolerant B cells were nevertheless normally responsive to stimulation with interleukin 4 and anti-CD40 Abs in vitro, suggesting that they retained the capacity to respond to mediators of T cell help. However, the tolerant B cells exhibited a proximal block in the sIg signaling pathway which prevented activation of receptor-associated tyrosine kinases in response to the binding of soluble HEL. The functional significance of this sIg signaling defect was confirmed by using a more potent membrane-bound form of HEL capable of triggering sIg signaling in tolerant B cells, which markedly restored their ability to collaborate with allogeneic Th cells and produce Ab. These findings indicate that Ag-specific B cells require two signals for mounting a T cell-dependent Ab response and identify regulation of sIg signaling as a mechanism for controlling self-reactive B cells.

scholarly journals CELL INTERACTIONS IN THE IMMUNE RESPONSE IN VITRO

1972 ◽  
Vol 136 (1) ◽  
pp. 49-67 ◽  
Author(s):  
Marc Feldmann ◽  
Antony Basten
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cells ◽  
B Cell ◽  
B Lymphocyte ◽  
Cell Contact ◽  
T Cell Factor ◽  
Lower Chamber ◽  
Pass Through

Tissue cultures with two compartments, separated by a cell impermeable nuclepore membrane (1 µ pore size), were used to investigate the mechanism of T-B lymphocyte cooperation. It was found that collaboration was as effective when the T and B lymphocyte populations were separated by the membrane as when they were mixed together. Critical tests were performed to verify that the membranes used were in fact cell impermeable. The specificity of the augmentation of the B cell response by various T cell populations was investigated. Only the response of B cells reactive to determinants on the same molecule as recognized by the T cells was augmented markedly. Specific activation of thymocytes by antigen was necessary for efficient collaboration across the membrane. The response of both unprimed and hapten-primed spleen cells was augmented by the T cell "factor" although, as expected, hapten-primed cells yielded greater responses. The T cell factor acted as efficiently if T cells were present or absent in the lower chamber. Thus the site of action of the T cell factor was not on other T cells, but was either on macrophages or the B cells themselves. The T cell-specific immunizing factor did not pass through dialysis membranes. The experiments reported here help rule out some of the possible theories of T-B cell collaboration. Clearly T-B cell contact was not necessary for successful cooperation to occur in this system. Possible theoretical interpretations of the results and their bearing on the detailed mechanism of T-B lymphocyte cooperation are discussed.

CD19+,CD27+, IgM+ B Cells of Patients with Persistent Polyclonal B Cell (PPBL) Proliferate in a Low Intensity CD40-CD154 Interaction and Show Evidence of Immunoglobulin Isotype Switching

Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 4920-4920
Author(s):  
Robert Delage ◽  
Emmanuelle Dugas-Bourdages ◽  
Annie Roy ◽  
Sonia Neron ◽  
Andre Darveau
Keyword(s):  
T Cells ◽  
B Cells ◽  
B Cell ◽  
B Lymphocytes ◽  
Cell Population ◽  
Genetic Defect ◽  
Memory B Cells ◽  
Isotype Switching ◽  
Low Intensity

Abstract Persistent polyclonal B cell lymphocytosis (PPBL) is a rare disorder characterized by an expansion of memory B cells CD19+, CD27+, IgM+. PPBL occurs mainly in female, is associated with HLA DR7, an increased level of serum IgM and the lymphocytes frequently show a bi-nucleated morphology. The patients have in most cases smoking habits and the clinical evolution is usually benign but we have previously described one case of lymphoma 19 years after a diagnosis of PPBL. Although the pathophysiology remains unknown, a familial occurrence is at the basis of this disorder suggesting a genetic defect. Moreover, multiple bcl-2\Ig gene rearrangements are present in all patients and an extra isochromosome 3 (i3)(q10) is frequently shown in the B cell population. The binding of CD40 to CD154 expressed on activated T cells plays a central role in B cell activation, proliferation and Ig isotype switching. We have previously shown that PPBL B lymphocytes were unable to respond to the proliferative signal delivered in vitro by CD40 in the CD40-CD154 system, indicating a possible defect in the CD40 pathway although CD40 expression, sequencing and tyrosine phosphorylation appeared normal. However, it has been shown recently that a reduced intensity of CD40-CD154 interaction in the presence of IL-2, IL-4 and IL-10 results in the proliferation, expansion and immunoglobulin secretion of normal memory CD19+,CD27+, IgM+ B cells. PPBL B lymphocytes sharing the same phenotype as normal memory B cells, we design a study to investigate the response of B lymphocytes from patient with PPBL in culture in high and low CD154 interaction. Proliferation and flow cytometry analysis of B lymphocytes from 6 patients with PPBL were closely monitored through a 14 day culture period and the Ig secretion was determined by Elisa. Our results show that a low intensity CD40- CD154 interaction in the presence of IL-2, IL-4 and IL-10 induces proliferation of the CD19+,CD27+,IgM+ PPBL population 6 to 20 times higher compared to high CD154 interaction. Interestingly, the CD19+, IgG+ cell population that constitutes less than 5% of the cell population at the beginning of the culture, increased over 25% on day 14. As for normal controls, we observed the emergence of a CD19+,CD27− cell population and the disappearance of surface IgD. Culture of B cells from patients with PPBL resulted in high Ig secretion. Moreover on day 14, Ig isotype analysis showed higher IgG levels compared to IgM. We conclude that PPBL B lymphocytes could proliferate in the CD40- CD154 system under proper condition and that proliferation also results in IgM and IgG secretion indicating an adequate CD40 signalling pathway. Moreover, this report provides the first evidence of in vitro Ig isotype switching of CD19+,CD27+,IgM+ B lymphocytes from PPBL. These results also suggest a possible defect in the interaction with T cells as observed in the hyper-IgM syndrome or alternatively, other cells from the microenvironment.

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