scholarly journals The in vitro effects of Bordetella pertussis lymphocytosis-promoting factor on murine lymphocytes. III. B-cell dependence for T-cell proliferation.

1979 ◽  
Vol 149 (5) ◽  
pp. 1001-1017 ◽  
Author(s):  
M K Ho ◽  
A S Kong ◽  
S I Morse

The nature of the helper lymphocytes in lymphocytosis-promoting factor (LPF)-induced proliferation was explored. Removal of macrophages from adherent splenocytes by either carbonyl-iron incubation or passage through Sephadex G-10 columns did not affect their synergistic function. Nor did cytolysis with Thy-1.2 antiserum and complement. The helper cells were found to be surface immunoglobulin-positive (sIg+) because they are retained by anti-Ig columns, susceptible to lysis by rabbit anti-mouse immunoglobulin and complement, and occurred in the sIg+ fractions of splenocytes after separation on the fluorescence-activated cell sorter. Further delineation of the surface markers on helper cells showed that complement receptors are not the determining marker for synergistic function. The requirement for B-helper cells in the stimulation of T lymphocytes by LPF is unique for a mouse of T-cell mitogen.

2012 ◽  
Vol 94 (2) ◽  
pp. 123-131 ◽  
Author(s):  
Céline Miroux ◽  
Olivier Morales ◽  
Khaldoun Ghazal ◽  
Samia Ben Othman ◽  
Yvan de Launoit ◽  
...  

2018 ◽  
Vol 30 (1) ◽  
pp. 17-e6 ◽  
Author(s):  
Frane Banovic ◽  
Jaime Tarigo ◽  
Hannah Gordon ◽  
James P. Barber ◽  
Robert M. Gogal

1975 ◽  
Vol 142 (6) ◽  
pp. 1591-1599 ◽  
Author(s):  
P F Piguet ◽  
H K Dewey ◽  
P Vassalli

A synergistic effect in the proliferative response to phytohemagglutinin (PHA) can be observed in cultures containing a mixture of mouse CBA/Ca lymph node cells (LNC) and syngeneic CBA/T6T6 thymocytes (ThC) when compared to cultures containing only one cell type. This effect was analyzed, at various days of culture and in LNC-ThC mixtures of different ratios, by comparing the origin of the cells in mitosis (detected by caryotypic analysis), the stimulation of DNA synthesis, the number of blasts, and the percentage of blasts labeled after pulses of [3H]thymidine (detected by autoradiography). The following conclusions were reached: (a) ThC are induced to proliferate by the presence of LNC, while they are almost unresponsive to PHA when cultured alone; and (b) the strongest "synergistic" effect is exerted on LNC, whose proliferation is markedly enhanced. Evidence is presented that this last effect is not specific to the presence of ThC, but results from a dilution of LNC which retards the time when the culture reaches a critical concentration of blasts, above which proliferation progressively stops. Thus, conditions of culture allowing the response to PHA of a low concentration of LNC leads to the most prolonged T-cell proliferation. These observations may be relevant to the types of T-cell interactions, "synergistic" or "suppressive," occurring during in vitro or in vivo immune responses.


Cells ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1606
Author(s):  
Peter Seiringer ◽  
Stefanie Eyerich ◽  
Kilian Eyerich ◽  
Daniela Dittlein ◽  
Anna Caroline Pilz ◽  
...  

Whilst the importance of keratinocytes as a first-line defense has been widely investigated, little is known about their interactions with non-resident immune cells. In this study, the impact of human keratinocytes on T cell effector functions was analyzed in an antigen-specific in vitro model of allergic contact dermatitis (ACD) to nickel sulfate. Keratinocytes partially inhibited T cell proliferation and cytokine production. This effect was dependent on the keratinocyte/T cell ratio and was partially reversible by increasing the number of autologous dendritic cells. The inhibition of T cell proliferation by keratinocytes was independent of the T cell subtype and antigen presentation by different professional antigen-presenting cells. Autologous and heterologous keratinocytes showed comparable effects, while the fixation of keratinocytes with paraformaldehyde abrogated the immunosuppressive effect. The separation of keratinocytes and T cells by a transwell chamber, as well as a cell-free keratinocyte supernatant, inhibited T cell effector functions to the same amount as directly co-cultured keratinocytes, thus proving that soluble factor/s account for the observed suppressive effects. In conclusion, keratinocytes critically control the threshold of inflammatory processes in the skin by inhibiting T cell proliferation and cytokine production.


Blood ◽  
1979 ◽  
Vol 54 (1) ◽  
pp. 146-158 ◽  
Author(s):  
KS Zuckerman ◽  
PJ Quesenberry ◽  
J Levin ◽  
R Sullivan

Abstract Endotoxin was detected in all erythropoietin preparations tested and was removed from four lots, without loss of erythropoietic activity, by adsorption with limulus amebocyte lysate. Comparison of adsorbed (endotoxin-depleted) and nonadsorbed (endotoxin-containing) erythropoietin preparations demonstrated significant inhibition of CFU- e and BFU-e in vitro by nonadsorbed erythropoietin at concentrations higher than 0.25 U/ml and 2.0 U/ml, respectively. CFU-e and BFU-e were inhibited significantly by readdition in vitro of 10(-5)-10(-3) mug of endotoxin per unit of limulus-adsorbed erythropoietin. Administration of saline or 6 U of nonadsorbed or adsorbed erythropoietin twice a day for 4 days of CF1 mice resulted in reticulocyte counts of 2.1%, 9.9%, and 15.9%, respectively. Nonadsorbed erythropoietin resulted in a 29% decrease in erythropoiesis, a 42% decrease in CFU-e, and a 16% increase in granulopoiesis in the marrow, whereas adsorbed erythropoietin caused a 28% increase in erythropoiesis, no significant change in CFU-e and a 19% decrease in granulopoiesis in the marrow. Both preparations resulted in marked increases in splenic erythropoiesis and granulopoiesis. The effects of adsorbed erythropoietin are similar to those produced following stimulation of hematopoiesis by endogenous erythropoietin. Hemopoietic changes induced by nonadsorbed erythropoietin in vivo and in vitro are affected substantially by contamination of the erythropoietin preparations with endotoxin.


1980 ◽  
Vol 29 (3) ◽  
pp. 1102-1110
Author(s):  
M C Woan ◽  
U K Forsum ◽  
D D McGregor

A soluble extract of Listeria monocytogenes bound firmly and in similar amounts to a variety of rat cells. Cells that bound this material differed in their capacity to stimulate the in vitro proliferation of lymphocytes obtained from the thoracic duct of Listeria-immune donors. The capacity of cells to serve as antigen-presenting cells in this system coincided or closely overlapped the expression on these cells of an Ia antigen-like structure. Three lines of evidence indicate that T cells respond to L. monocytogenes antigen: the responder cells are members of a nylon-wool nonadherent population that lacks readily detectable surface immunoglobulin; they express determinants recognized by the W3/25 monoclonal antibody (a surface marker of rat peripheral T cells); and they are stimulated optimally by L. monocytogenes antigen when the latter is displayed on cells that share a haplotype with the responder lymphocytes.


2020 ◽  
Vol 11 ◽  
Author(s):  
Christian Binder ◽  
Felix Sellberg ◽  
Filip Cvetkovski ◽  
Erik Berglund ◽  
David Berglund

Antibodies are commonly used in organ transplant induction therapy and to treat autoimmune disorders. The effects of some biologics on the human immune system remain incompletely characterized and a deeper understanding of their mechanisms of action may provide useful insights for their clinical application. The goal of this study was to contrast the mechanistic properties of siplizumab with Alemtuzumab and rabbit Anti-Thymocyte Globulin (rATG). Mechanistic assay systems investigating antibody-dependent cell-mediated cytotoxicity, antibody-dependent cell phagocytosis and complement-dependent cytotoxicity were used to characterize siplizumab. Further, functional effects of siplizumab, Alemtuzumab, and rATG were investigated in allogeneic mixed lymphocyte reaction. Changes in T cell activation, T cell proliferation and frequency of naïve T cells, memory T cells and regulatory T cells induced by siplizumab, Alemtuzumab and rATG in allogeneic mixed lymphocyte reaction were assessed via flow cytometry. Siplizumab depleted T cells, decreased T cell activation, inhibited T cell proliferation and enriched naïve and bona fide regulatory T cells. Neither Alemtuzumab nor rATG induced the same combination of functional effects. The results presented in this study should be used for further in vitro and in vivo investigations that guide the clinical use of immune modulatory biologics.


Sign in / Sign up

Export Citation Format

Share Document