scholarly journals Lymphocyte surface immunoglobulin density and immunoglobulin secretion in vitro in chronic lymphocytic leukemia (CLL)

Blood ◽  
1978 ◽  
Vol 52 (3) ◽  
pp. 601-608 ◽  
Author(s):  
YH Chen ◽  
P Heller

Abstract Lymphocyte surface immunoglobulin (SIg) and immunoglobulin (Ig) secretion were studied in 14 patients with chronic lymphocytic leukemia (CLL) and 12 healthy subjects. The determination of SIgM-bearing (SIgM+) cells by immunofluorescent staining and the quantification of SIgM by radioimmunoassay (RIA) permitted the calculation of the SIgM density. In 12 normal subjects the percentage of SIgM+ cells averaged 8% (range 4%-12%) and the SIgM density 10.2 ng antigenic equivalent/10(6) SIgM+ cells (SD 4.3). In 12 patients with CLL the respective figures were 68% (range 35%-90%) and 0.68 ng (SD 0.57). Ig secretion from pokeweed mitogen-stimulated CLL cells was markedly diminished as compared with normal lymphocytes. In coculture experiments CLL cells had no suppressive effect on Ig secretion of normal lymphocytes and normal lymphocytes did not enhance Ig secretion leukemic lymphocytes. These results indicate that the impaired secretory activity of CLL cells results from an intrinsic anomaly of these cells.

Blood ◽  
1978 ◽  
Vol 52 (3) ◽  
pp. 601-608 ◽  
Author(s):  
YH Chen ◽  
P Heller

Lymphocyte surface immunoglobulin (SIg) and immunoglobulin (Ig) secretion were studied in 14 patients with chronic lymphocytic leukemia (CLL) and 12 healthy subjects. The determination of SIgM-bearing (SIgM+) cells by immunofluorescent staining and the quantification of SIgM by radioimmunoassay (RIA) permitted the calculation of the SIgM density. In 12 normal subjects the percentage of SIgM+ cells averaged 8% (range 4%-12%) and the SIgM density 10.2 ng antigenic equivalent/10(6) SIgM+ cells (SD 4.3). In 12 patients with CLL the respective figures were 68% (range 35%-90%) and 0.68 ng (SD 0.57). Ig secretion from pokeweed mitogen-stimulated CLL cells was markedly diminished as compared with normal lymphocytes. In coculture experiments CLL cells had no suppressive effect on Ig secretion of normal lymphocytes and normal lymphocytes did not enhance Ig secretion leukemic lymphocytes. These results indicate that the impaired secretory activity of CLL cells results from an intrinsic anomaly of these cells.


2016 ◽  
Vol 64 (4) ◽  
pp. 894-898 ◽  
Author(s):  
Dorota Koczkodaj ◽  
Sylwia Popek ◽  
Szymon Zmorzyński ◽  
Ewa Wąsik-Szczepanek ◽  
Agata A Filip

One of the research methods of prognostic value in chronic lymphocytic leukemia (CLL) is cytogenetic analysis. This method requires the presence of appropriate B-cell mitogens in cultures in order to obtain a high mitotic index. The aim of our research was to determine the most effective methods of in vitro B-cell stimulation to maximize the number of metaphases from peripheral blood cells of patients with CLL for classical cytogenetic examination, and then to correlate the results with those obtained using fluorescence in situ hybridization (FISH). The study group involved 50 consecutive patients with CLL. Cell cultures were maintained with the basic composition of culture medium and addition of respective stimulators. We used the following stimulators: Pokeweed Mitogen (PWM), 12-O-tetradecanoylphorbol 13-acetate (TPA), ionophore, lipopolysaccharide (LPS), and CpG-oligonucleotide DSP30. We received the highest mitotic index when using the mixture of PWM+TPA+I+DSP30. With classical cytogenetic tests using banding techniques, numerical and structural aberrations of chromosomes were detected in 46 patients, and no change was found in only four patients. Test results clearly confirmed the legitimacy of using cell cultures enriched with the mixture of cell stimulators and combining classical cytogenetic techniques with the FISH technique in later patient diagnosing.


1987 ◽  
Vol 2 (3) ◽  
pp. 173-176
Author(s):  
Teodoro Chisesi ◽  
Michele Vespignani ◽  
Giovanni Capnist

Three groups of patients with immunoproliferative disorders (15 multiple myeloma, 11 non-Hodgkin's lymphoma, 21 chronic lymphocytic leukemia) were studied by immunological characterization and compared to a group of 20 normal subjects (controls) using anti-immunoglobulin coated polyacrylamide beads (T-B Quantigen test, QT), erythrocyte rosettes (ER), surface immunoglobulin (SIg), and monoclonal antibodies for T and B cells (OKT3; OKT11; OKT8; OKT4; IaDR); null cells (NC) and double marker (DM) cells were also considered. The values for normal subjects for T-B, NC and DM cells were comparable. Results for the patient groups strikingly differed. There were progressively larger differences between the T and B percentages obtained with different techniques. The largest differences were seen in patients with chronic lymphocytic leukemia and the smallest in multiple myeloma patients; values were intermediate in non-Hodgkin lymphoma. The different findings were related to the number of DM cells (ER +, SIg+ QT+) and the different tests used. The importance of these findings in the diagnostic appproach to lymphoproliferative disorders is discussed.


Blood ◽  
1973 ◽  
Vol 42 (4) ◽  
pp. 591-600 ◽  
Author(s):  
Georg Cohnen ◽  
Steven D. Douglas ◽  
Erika König ◽  
Günter Brittinger

Abstract The in vitro response of lymphocytes from patients with chronic lymphocytic leukemia (CLL) to pokeweed mitogen (PWM) was diminished and/or delayed. Electron microscopy of PWM stimulated CLL lymphocytes revealed both PHA-type blast cells and plasmacytoid cells. Some PHA-type blast cells were indistinguishable from corresponding normal cells. However, many transformed cells had a reduced cell, cytoplasmic, and nuclear area in comparison to transformed lymphocytes from normal individuals. In 7- and 9-day cultures, 5-10% of the cells present were plasmacytoid. No ultrastructural differences were observed between the plasmacytoid cells in PWM stimulated cultures of normal and CLL lymphocytes. The findings support the concept that the circulating lymphocyte population in CLL is comprised predominantly of abnormal cells, in addition to a small number of normal T and B lymphocytes.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ana Colado ◽  
Esteban Enrique Elías ◽  
Valeria Judith Sarapura Martínez ◽  
Gregorio Cordini ◽  
Pablo Morande ◽  
...  

AbstractHypogammaglobulinemia is the most frequently observed immune defect in chronic lymphocytic leukemia (CLL). Although CLL patients usually have low serum levels of all isotypes (IgG, IgM and IgA), standard immunoglobulin (Ig) preparations for replacement therapy administrated to these patients contain more than 95% of IgG. Pentaglobin is an Ig preparation of intravenous application (IVIg) enriched with IgM and IgA (IVIgGMA), with the potential benefit to restore the Ig levels of all isotypes. Because IVIg preparations at high doses have well-documented anti-inflammatory and immunomodulatory effects, we aimed to evaluate the capacity of Pentaglobin and a standard IVIg preparation to affect leukemic and T cells from CLL patients. In contrast to standard IVIg, we found that IVIgGMA did not modify T cell activation and had a lower inhibitory effect on T cell proliferation. Regarding the activation of leukemic B cells through BCR, it was similarly reduced by both IVIgGMA and IVIgG. None of these IVIg preparations modified spontaneous apoptosis of T or leukemic B cells. However, the addition of IVIgGMA on in vitro cultures decreased the apoptosis of T cells induced by the BCL-2 inhibitor, venetoclax. Importantly, IVIgGMA did not impair venetoclax-induced apoptosis of leukemic B cells. Overall, our results add new data on the effects of different preparations of IVIg in CLL, and show that the IgM/IgA enriched preparation not only affects relevant mechanisms involved in CLL pathogenesis but also has a particular profile of immunomodulatory effects on T cells that deserves further investigation.


Blood ◽  
2021 ◽  
Author(s):  
Billy Michael Chelliah Jebaraj ◽  
Annika Müller ◽  
Rashmi Priyadharshini Dheenadayalan ◽  
Sascha Endres ◽  
Philipp M. Roessner ◽  
...  

Covalent Bruton tyrosine kinase (BTK) inhibitors such as ibrutinib have proven to be highly beneficial in the treatment of chronic lymphocytic leukemia (CLL). Interestingly, the off-target inhibition of IL-2-inducible T-cell kinase (ITK) by ibrutinib may also play a role in modulating the tumor microenvironment, potentially enhancing the treatment benefit. However, resistance to covalently binding BTK inhibitors can develop by a mutation in cysteine 481 of BTK (C481S), which prevents the irreversible binding of the drugs. In the present study we performed pre-clinical characterization of vecabrutinib, a next generation non-covalent BTK inhibitor, with ITK inhibitory properties similar to those of ibrutinib. Unlike ibrutinib and other covalent BTK inhibitors, vecabrutinib showed retention of the inhibitory effect on C481S BTK mutants in vitro, similar to that of wildtype BTK. In the murine Eµ-TCL1 adoptive transfer model, vecabrutinib reduced tumor burden and significantly improved survival. Vecabrutinib treatment led to a decrease in CD8+ effector and memory T-cell populations, while the naïve populations were increased. Of importance, vecabrutinib treatment significantly reduced frequency of regulatory CD4+ T-cells (Tregs) in vivo. Unlike ibrutinib, vecabrutinib treatment showed minimal adverse impact on activation and proliferation of isolated T-cells. Lastly, combination treatment of vecabrutinib with venetoclax was found to augment treatment efficacy, significantly improve survival and lead to favourable reprogramming of the microenvironment in the murine Eµ-TCL1 model. Thus, non-covalent BTK/ITK inhibitors such as vecabrutinib may be efficacious in C481S BTK mutant CLL, while preserving the T-cell immunomodulatory function of ibrutinib.


Blood ◽  
2021 ◽  
Author(s):  
Ishwarya Murali ◽  
Siddha Kasar ◽  
Aishath Naeem ◽  
Svitlana Tyekucheva ◽  
Jasneet Kaur Khalsa ◽  
...  

Inhibitors of Bruton's tyrosine kinase (BTKi) and phosphatidylinositol 3-kinase delta (PI3Kδi) that target the B cell receptor (BCR) signaling pathway have revolutionized the treatment of chronic lymphocytic leukemia (CLL). While mutations associated with resistance to BTK inhibitors have been identified, limited data are available on mechanisms of resistance to PI3Kδi. Here we present findings from longitudinal whole-exome sequencing of multiply relapsed CLL patients (Ncases=28) enrolled in PI3Ki trials. The non-responder subgroup was characterized by baseline activating mutations in MAP2K1, BRAF and KRAS in 60% of patients. PI3Kδ inhibition failed to inhibit ERK phosphorylation (pERK) in non-responder CLL cells with and without mutations, while treatment with MEKi rescued ERK inhibition. Overexpression of MAP2K1 mutants in vitro led to increased basal and inducible pERK and resistance to idelalisib. These data demonstrate that MAPK/ERK activation plays a key role in resistance to PI3Kδi in CLL and provide rationale for combination therapy with PI3Kδ and ERK inhibitors.


Blood ◽  
2004 ◽  
Vol 103 (12) ◽  
pp. 4389-4395 ◽  
Author(s):  
Freda K. Stevenson ◽  
Federico Caligaris-Cappio

Abstract The finding that chronic lymphocytic leukemia (CLL) consists of 2 clinical subsets, distinguished by the incidence of somatic mutations in the immunoglobulin (Ig) variable region (V) genes, has clearly linked prognosis to biology. Antigen encounter by the cell of origin is indicated in both subsets by selective but distinct expression of V genes, with evidence for continuing stimulation after transformation. The key to distinctive tumor behavior likely relates to the differential ability of the B-cell receptor (BCR) to respond. Both subsets may be undergoing low-level signaling in vivo, although analysis of blood cells limits knowledge of critical events in the tissue microenvironment. Analysis of signal competence in vitro reveals that unmutated CLL generally continues to respond, whereas mutated CLL is anergized. Differential responsiveness may reflect the increased ability of post-germinal center B cells to be triggered by antigen, leading to long-term anergy. This could minimize cell division in mutated CLL and account for prognostic differences. Unifying features of CLL include low responsiveness, expression of CD25, and production of immunosuppressive cytokines. These properties are reminiscent of regulatory T cells and suggest that the cell of origin of CLL might be a regulatory B cell. Continuing regulatory activity, mediated via autoantigen, could suppress Ig production and lead to disease-associated hypogammaglobulinemia. (Blood. 2004;103:4389-4395)


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