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At least 19 recordsLinked to original sources
PubMed1979

Human T and B lymphoid cells: an electron microscopic study on thymocytes, peripheral blood lymphocytes, mitogen-stimulated cells and lymphoid cell lines.

Human lymphoid cells were studied by electron microscopy to find any morphological difference between T and B cells. The T cell population generally contains a smaller amount of the rough endoplasmic reticulum than the B cell in various functional states, i.e. peripheral blood lymphocytes of normal individuals, mitogen-stimulated lymphoblasts and lymphoid cell lines. This may depend on greater need of the rough endoplasmic reticulum for immunoglobulin synthesis in B cells, even though T cells produced some soluble mediators. Other differences between T and B cells are as follows: (1) Peripheral blood T lymphocytes often have clustered dense granules, while granules containing parallel tubular structures are more frequently seen in B lymphocytes. (2) Cultured T cell lines usually exhibit a higher nuclear-cytoplasmic ratio and less prominent nucleoli than B cell lines.

B-Lymphocytes↗
PubMed1975

Interaction in culture between mouse ascites hepatoma (MH-134) cells and lymphoid cells of isologous mice.

Thymocytes or lymphocytes of mesenteric lymph nodes were obtained from mice bearing subcutaneously mouse ascites hepatoma MH-134 for 5 to 40 days. These lymphoid cells were added into the cultures of MH-134 cells. Morphological changes of cells in the mixed cultures were observed by time-lapse cinemicrography for the period of 4 weeks. Lymphoid cells were phagocytosed by MH-134 cells, and, in most cases, the tumor cells did not undergo any damage due to the phagocytosis. The exceptional cases were as follows: When MH-134 cells were mixed with thymocytes from mice bearing MH-134 tumor for 5 days, MH-134 cells phagocytosed thymocytes but some of them died later. In the mixed cultures of MH-134 cells and thymocytes or mesenteric lymph node lymphocytes from mice bearing MH-134 for 14 or 15 days, MH-134 cells phagocytosed lymphoid cells but died later by the burst of cytoplasm. By the burst many lymphoid cells phagocytosed appeared from the broken cytoplasm of MH-134 cells and, in some cases, the lymphoid cells looked to be alive. These findings suggest the possibility that lymphoid cells attack tumor cells not only from the cell surface but also from the inside being phagocytosed by tumor cells.

Animals↗
PubMed1975

A procedure for removing red cells and dead cells from lymphoid cell suspensions.

A procedure is described for simultaneously removing red cells and dead cells from lymphoid cell suspensions, based on the observation that when populations of lymphoid cells are centrifuged on a mixture of Isopaque/Ficoll, dead cells and red cells sediment whereas viable cells float. The technique very efficiently removed red cells from a wide range of lymphoid cell suspensions and eliminated lymphocytes killed by mechanical stress, by antibody and complement and by prolonged tissue culture. The depletion of red cells was greater than 99% and the recovery of viable lymphocytes usually greater than 90%, the resulting cell suspensions being around 95-100% viable. The immunological activity of B cells, helper T cells and cytotoxic T cells virtually unimpaired by the separation procedure.

Animals↗
PubMed1975

[Changes of lymphoid cell cytotoxicity, shown in vitro, of mice bearing a syngeneic tumor after injection of killed tumor cells].

Lymphoid cells from mice bearing a syngeneic tumour show a cytotoxic activity in vitro, occuring in two succesive waves. Normally inactive during the second week after grafting, lymphoid cells have a marked killing ability during this period when heavily irradiated tumour cells have been injected on the 6th day. On the contrary, the cytotoxicity due to the graft, which is important from the 20th to the 30th day, is inhibited by injection of killed tumour cells 15 days before the test. Quantitative variations of the tumour antigen liberated in the animal may be responsible for those effects.

Animals↗
PubMed1978

In situ lymphoid cells of mouse mammary tumors. III. In vitro stimulation of tumor cell survival by lymphoid cells separated from mammary tumors.

Lymphoid cells were isolated by isokinetic gradient centrifugation from mouse mammary tumors and evaluated for their ability to affect tumor cell survival with the microcytotoxicity assay. In all experiments stimulation of the growth or survival of tumor cells was seen. This stimulation was not seen with separated lymphoid cells treated with anti-lymphocyte serum and complement. The lymphoid cells separated from tumors were more stimulatory than were lymph node cells; even toxic to the tumor cells, the separated tumor-associated lymphoid cells were markedly stimulatory. The gradient procedure had no effect on the activity of sensitized lymph node cells, but it did separate cytotoxicity and stimulation into different fractions.

Animals↗
PubMed1976

Immunostimulation of highly immunogenic target tumor cells by lymphoid cells in vitro.

A highly immunogenic mouse tumor was studied with the use of microcytotoxicity test, performed at lymphoid cell:target tumor cell ratios ranging from 1:1 to 1,000:1 at various times during tumour growth and after tumor excision. Although the tumor was highly immunogenic, in vitro lymphoid cell-mediated cytotoxicity was shown only with lymphoid cells from hyperimmunized mice, i.e., mice that had "seen" the tumor more than once. Instead, the lymphoid cells harvested 2 and 3 weeks after tumor inoculation, as well as after excision of the tumor, stimulated the target cells. At 4 weeks after inoculation of the tumor, there appeared to be neither stimulation nor inhibition of the target tumor cells, though at this point the growth of this highly immunogenic tumor had been arrested in vivo.

Animals↗
PubMed1977

Bone marrow kinetic studies on three patients with myelomatosis. Indications for malignant proliferation within both the plasma cell and lymphoid cell compartments.

The proliferative activity has been studied in lymphocyte and plasma cell populations of purified bone marrow from three myeloma patients. In one of them, proliferation was also recorded in blood lymphocytes. Immunofluorescence studies, using idiotypic antisera against the M-component, were performed to identify lymphocytes and plasma cells belonging to the malignant cell clone. Pulse incubations with 3H-thymidine (3H-TdR) were made in vitro. Autoradiographic analyses revealed a higher overall 3H-TdR labelling index in the myeloma cell populations than in normal control cell populations. A few labelled plasma cells were observed in the myeloma cases (2.5-5%) but the major fraction (11.5-14%) and intensity of labelled cells were found among the lymphoid cells. This indicates that the proliferation of malignant cells in myeloma occurs not only within the plasma cell but also in the lymphoid cell population. The results provide additional support for the assumption that B-lymphocytes are part of the malignant cell clone in myelomatosis and most likely precursors to the myeloma plasma cells.

Autoradiography↗
PubMed1976

Complement-dependent immunoglobulin G receptor function in lymphoid cells.

Lymphoid cells are unable to lyse antibody-coated target cells in the presence of normal immunoglobulin G (IgG), presumably because their surface receptors of IgG are blocked. However, when target cells are sensitized with antibodies and complement, IgG receptors are unblocked and cytotoxicity occurs even in the presence of normal IgG. Thus, IgG receptors may function in vivo despite the relatively high concentations of IgG in serum and interstitial fluid.

Antigen-Antibody Complex↗
PubMed1975

Evidence for the non-protein nature of the receptor for the enterotoxin in Vibrio cholerae on murine lymphoid cells.

Lymphoid cells from A/J and BALB/c strains of mice were iodinated with 125I by the lactoperoxidase method and the plasma membranes were disrupted by freezing and thawing or with 0.5 percent Nonidet P-40, a nonionic detergent. Attempts to find choleragen reactive iodinated material in 0.5 percent Nonidet P-40 lysates were unsuccessful even when the cells were incubated with choleragen before lysis. Freezing and thawing the cells resulted in the release of iodinated choleragen reactive material. The interaction of choleragen with the iodinated material could be inhibited (at low choleragen concentrations) or enhanced (at high choleragen concentrations) by the addition of the ganglioside G-M1 to the the immune precipitation system. The results are consistent with the hypothesis that the receptor for choleragen is a glycolipid and reduce, but do not totally eliminate, the likelihood that the receptor is glycoprotein in nature.

Animals↗
PubMed1979

[Presence of clusters of Langerhans cells and lymphoid cells in the peritumoral infiltrate of a case of basal cell naevus syndrome. Ultrastructural study (author's transl)].

A case of naevoid basal cell carcinoma syndrome with clusters of Langerhans' and lymphoid cells in the inflammatory peritumoral infiltrate, is reported. Electron microscopy shows intercellular contacts between eight to ten lymphoid cells and a single Langerhans' cell. These contacts occur over limited areas of the cell membranes by means of zones of high electron density on the outer edge of the cytoplasm. The functional significance of this finding is discussed, bearing in mind that recent observations have established certain analogies between Langerhans' and interdigitating reticulum cells. The latter might, within the thymus-dependent region of the lymph nodes, contribute to the formation of a micro-environment favourable to certain immunological activities of T-lymphocyte populations.

Adolescent↗
PubMed1975

Interaction in culture between mouse ascites mammary carcinoma (MM2) cells and lymphoid cells of isologous mice.

MM2 cells, ascitic tumor originated from spontaneous mammary carcinoma of C3H/He mouse, were mix-cultured with lymphoid cells of thymus or mesenteric lymph nodes from isologous animals of the same sex. The interaction in culture between these cells was examined by time-lapse cinemicrography. In single culture, thymocytes, mesenteric lymph node lymphocytes and MM2 cells were kept for 7 days with little change in cell population. Lymphocytes of both sources showed a marked decrease in cell number when cultured together with MM2 cells, being evidently phagocytosed by MM2 cells. Lymphocytes from MM2-bearing mice or mice sensitized with deoxycholate-extracted MM2 antigen were also all phagocytosed. MM2 cells exhibited no sign of damage or degeneration due to the phagocytosis. Thymocytes were not phagocytosed by histiocytes obtained from ascitic fluid 3 days after i.p. injection of 5% starch suspension. Phagocytosis of erythrocytes or lymphoid cells from spleen by MM2 cells was not detected.

Animals↗
PubMed1976

Separation of human lymphoid cells by preparative cell electrophoresis. III. Studies on cells of lymphoid organs in hematological normal persons.

Blood and bone marrow lymphocytes and cells of lymphoid organs in hematologically normal persons have been studied using free-flow electrophoresis by which a preparative separation of cells according to their electrophoretic mobility is achieved. The results are demonstrated as electrophoretic distributions. Blood lymphocytes have a peak corresponding to relative high electrophoretic mobility, whereas the majority of marrow lymphocytes is found in fractions corresponding to low electrophoretic mobility. The distributions of small lymphocytes from tonsil, spleen and lymphnode either resemble the distribution of blood lymphocytes or have a bimodal fashion with peaks corresponding to blood lymphocytes or marrow lymphocytes. Large lymphoid cells capable of DNA synthesis are concentrated in fractions of intermediate mobility. The results confirm the concept that peripheral T cells have a high electrophoretic mobility whereas most B cells are of low mobility. In contrast to peripheral T cells, cells of the thymus have an intermediate or low electrophoretic mobility. Thus, it appears that in the lymphoid cell system differences in the electrophoretic mobility not only reflect different functional properties but also differences in maturation stages.

Adult↗
PubMed1976

Cytotoxicity responses to melanoma cells by human lymphoid cell subpopulations.

Lymphoid cell subpopulations from normal donors and patients with malignant melanoma were assessed for cytotoxicity. Unfractionated mononuclear cells and T-cells from melanoma patients gave cell-mediated cytotoxic (CMC) responses to melanoma target cells but not to human fibroblasts. These specific CMC responses to melanoma cells were partially inhibited by autologous serum. Non-T-cells and nonrosetting cells from melanoma patients were not directly cytolytic for melanoma target cells; however these same subpopulations were cytotoxic in the presence of autologous serum, which indicated antibody-dependent cell cytotoxic responses. Non-T-cell subpopulations from normal donors were not cytotoxic when incubated with autologous serum. A third cytotoxic mechanism was demonstrated with complement (C3) receptor-activated lymphocytes. From both melanoma patients and normal donors, cells forming rosettes with erythrocyte-antibody-complement were nonspecifically cytotoxic for lung fibroblasts and melanoma target cells, These responses were independent of antibody, since melanoma serum presumably containing antibody to melanoma target cells neither enhanced nor blocked cytotoxicity mediated by C3 receptor-bearing lymphocytes. The results indicated that lymphoid cell subpopulations from the same melanoma patient could express at least three different lymphocyte-mediated cytotoxicity mechanisms against melanoma target cells.

Antibodies↗
PubMed1975

Comparisons of surface markers on Herpesvirus-associated lymphoid cells of nonhuman primates and established human lymphoid cell lines.

Herpesvirus saimiri (HVS)-owl monkey lymphoid cells were found to have high levels of surface receptor for sheep erythrocytes and erythrocytes of 3 other species. These HVS-lymphoid cells lacked a receptor for modified complement. Lymphoid cells of one HVS-owl monkey line showed evidence for the presence of surface immunofluorescent staining with anti-kappa chain serum. Cells of an established HVS-marmoset lymphoid line had similar surface markers. Of 4 established human lymphoid cell lines, all lacked a receptor for sheep erythrocytes, 3 showed evidence for the presence of receptor for modified complement, and 3 showed immunofluorescent evidence for the presence on the surface of both heavy and light chain immunoglobulin. Preliminary data on an established Epstein-Barr virus (EBV)-owl monkey lymphoid cell line indicated a lack of receptor for sheep erythrocytes, presence of receptor for modified complement, and surface immunofluorescent staining with both anti-heavy and anti-light chain sera.

Animals↗
PubMed1976

Stimulation of lymphoid cells from normal and immune mice by syngeneic BALB/c plasma cell tumors.

Lymphoid cells from normal and immunized BALB/c mice could be stimulated in vitro by syngeneic PCT contrasted with an absence of response to a number of other tumors. Maximal responses of normal cells to PCT were found to occur 5 days after the initiation of the cultures at an optimal responding:stimulation cell ratio of 1:2. MLTI activity of normal cells could not be blocked or enhanced by PCT myeloma protein products indicating that MLTI reactivity was directed against non-idiotypec cell surface determinants. Lymphoid cells from immunized mice demonstrated increased MLTI responses to cells of the immunizing tumor but not to other PCT, indicating that the post-immunization MLTI responses were primarily to individual rather than shared tumor cell surface antigens. Activity of both normal and immunized spleen cells was found to involve thymus-derived lymphocytes. The persistence of residual MLTI activity after treatment with anti-theta serum and complement, however, implicated participation of non-theta antigen-bearing cells in MLTI reactivity. From these data, we conclude that lymphoid cells from un-immunized mice are capable of T cell-dependent reactivity to syngeneic PCT-associated antigens and that elevations in these reactivities after immunization may reflect specific cellular immune responses.

Animals↗
PubMed1977

The effect of cell synchronization upon the detection of T and B lymphoid cell receptors on two continuous lymphoid cell lines.

In the present study, the effect of the cell synchronization on the detection of T and B cell surface markers of two continuous lines of lymphoid cells (FL-74 and CT45-S) was examined. Suspension cultures were synchronized by deprivation of isoleucine and surface markers were quantitated by T rosette formation with guinea pig erythrocytes (E) and B rosette formation with an erythrocyte-antibody-complement (EAC) complex. After 24 hr, cells were resuspended in complete culture medium. Virtually 100% of FL-74 cells expressed the T cell marker at time 0, with a progressive decline to 80% at saturation density. A bell-shaped curve for expression of the EAC marker on CT45-S cells was seen with maximum expression in the logarithmic phase of the growth cycle. Spent culture medium was examined for the presence of free soluble receptor. Preincubation of E and EAC in appropriate old medium resulted in 42% inhibition of E rosettes and 42% inhibition of EAC rosettes with FL-74 and CT45-S cells, respectively. Thus quantitation of lymphocyte subpopulations as B, T or null cells with these cellular markers may be influenced by the age of the cell examined, phase of the cell cycle and the amount of free receptor present in the surrounding medium.

B-Lymphocytes↗