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At least 19 recordsLinked to original sources
PubMed1976

Recruitment of effector lymphocytes by initiator lymphocytes. Recruited lymphocytes are immunospecific and include graft-versus-host-reactive lymphocytes.

We have shown previously that initiator T lymphocytes (ITL), sensitized in vitro against fibroblast antigens, recruit effector T cells in vivo. After injection into hind footpads of syngeneic recipients, sensitized ITL migrated to the draining popliteal lymph nodes (PLN) and activated a trapping mechanism by which circulating lymphocytes were recruited in the PLN. This paper reports experiments designed to test the immunospecificity of these recruited T lymphocytes (RTL). We found that immunospecific RTL were depleted from other lymphoid organs during recruitment in the PLN. However, immunospecific ITL were not depleted from spleens during PLN recruitment. Thus ITL and RTL are functionally distinguishable. We show that specific GVH reactive lymphocytes were also lost from spleens and distal lymph nodes during trapping of RTL in the PLN. Thus, the trapping phase of the recruitment response is immunospecific, as are the sensitization and effector phases. The trapped RTL are antigen-specific, and include the pool of GVH-reactive-lymphocytes committed to the same alloantigen. Thus, it appears that GVH-reactive cells respond to syngeneic ITL sensitized against allogeneic fibroblasts.

Animals↗
PubMed1977

Distinctive functional properties of human blood L lymphocytes: a comparison with T lymphocytes, B lymphocytes, and monocytes.

Human blood lymphocytes with high affinity Fc receptors have been operationally named L lymphocytes because of membrane-labile IgG markers. L lymphocytes lack membrane-incorporated immunoglobulin and do not form rosettes with sheep red blood cells coated with IgM antibody and mouse complement. These lymphocytes are capable of binding IgG in normal human serum at 4 degrees C and will form rosettes with human lymphocytes coated with Ripley IgG. In this study, functional in vitro properties of isolated L lymphocytes were compared with T lymphocytes, B lymphocytes, and monocytes. To obtain these mononuclear populations, first, plastic adherent monocytes were harvested. T lymphocytes were then isolated by centrifugation of E rosette-forming cells, and other rosetting techniques were employed to isolate L and B lymphocytes by negative selection. The functional properties of L lumphocytes were completely unlike those of T cells, B cells, or monocytes. L lymphocytes did not proliferate in response to mitogens, soluble antigens, or cell surface antigens. Moreover, this population could not replace monocytes in helping T lymphocytes respond to concanavalin A and pokeweed mitogen. Once T cells were supplemented with monocytes, however, the addition of L lymphocytes to the culture greatly enhanced the T lymphocytes proliferative response to phytohemagglutinin, concanavalinA, purified protein derivative (PPD), and streptokinase/streptodornase. L lymphocytes were not a subset of B cells. They did not spontaneously develop surface Ig in culture, and pokeweek mitogen could not induce them to transform and generate cytoplasmic Ig detectable by immunofluorescence. Mixtures of B cells and T cells responded to pokeweed mitogen better than do T cells alone. In contrast, enhanced reactivity with L and T cell combinations was not observed. Another sharp difference between these two populations was the stimulator capacity of each in mixed lymphocyte culture. When B and L lymphocytes were carefully monocyte-depleted, only B cells were effective stimulators of autologous and allogeneic lymphocytes. In comparison with T cells, B cells, and monocytes, L lymphocytes were the only effective killers of human blood lymphocytes sensitized with IgG. L lymphocytes, then, have cytotoxic potential, but cannot proliferate in response to various stimulants or become antibody-producing cells. These findings suggest that L lymphocytes comprise a third lymphocyte population.

Antigen-Antibody Reactions↗
PubMed1976

Lymphocyte transformation induced by autologous cells. IV. Human T-lymphocyte proliferation induced by autologous or allogeneic non-T lymphocytes.

An autologous mixed lymphocyte reaction was demonstrated between T and non-T lymphocytes. Sheep erythrocyte rosetting was used to separate human lymphocytes into T and non-T lymphoid preparations. Non-T lymphocytes stimulated the proliferation of autologous T lymphocytes. The cell in this preparation that was most stimulatory had the characteristics of a K lymphocyte. The allogeneic mixed lymphocyte reaction was also shown to reflect the proliferation of T lymphocytes stimulated by allogeneic non-T lymphocytes. Proliferation of T lymphocytes in the allogeneic mixed lymphocyte culture probably reflects a response to both foreign histocompatibility determinants and determinants present on non-T lymphocytes. It is suggested that the proliferative response of T lymphocytes to autologous non-T lymphocytes may be a step in the process by which T lymphocytes regulate immunity.

Blood↗
PubMed1978

Adaptive differentiation of murine lymphocytes. I. Both T and B lymphocytes differentiating in F1 transplanted to parental chimeras manifest preferential cooperative activity for partner lymphocytes derived from the same parental type corresponding to the chimeric host.

The concept of adaptive (selective) differentiation preducts that early differentiation of lymphocytes is conditioned by the environment in which such differentiation takes place. These processes appear to involve selection of lymphocytes according to their self-recognition between interacting lymphocytes is, at least in part, controlled by major histocompatibility complex-linked genes, then adaptive differentiation is also controlled by these genes. In these studies, we have tested the capacities of helper T lymphocytes and hapten-specific B lymphocytes primed in the environments of various combinations of bone marrow chimeras prepared between two parental strains (i.e. A/J and BALB/c) and their corresponding F1 hybrid (CAF1) to interact with primed B and T lymphocytes derived from conventional parent and F1 donors as well as all of the corresponding bone marrow chimera combinations. The results demonstrate clearly that (a) F1 transplanted to F1 chimeric lymphocytes display no restriction in terms of cooperative activity with all of the various partner cell combinations; (b) parent transplanted to F1 chimeric lymphocytes manifest effective cooperative activity only for partner cells from F) or parental donors corresponding to the haplotype of the original bone marrow donor, thereby behaving phenotypically just like conventional parental lymphocytes; and (c) F1 transplanted to parent chimeric lymphocytes display restricted haplotype preference in cooperating best with partner lymphocytes sharing the H-2 haplotype, either entirely or codomimantly, of the parental chimeric host. The implications of these findings for understanding certain controlling mechanisms for lymphocyte differentiation are discussed.

Animals↗
PubMed1975

Mixed lymphocyte reactivity of human lymphocytes primed in vitro. I. Secondary response to allogenic lymphocytes.

In order to study the mixed lymphocyte culture reactivity of human lymphocytes primed in vitro, a nucleopore culture chamber technique allowing human lymphocytes to be cultured for a period of at least two weeks has been developed. During the primary culture period in nucleopore chambers, human lymphocytes were sensitized against mitomycin-treated allogenic stimulating cells. It was shown that the stimulated lymphocytes underwent a blastogenic reaction and the results suggest a reversion to the state of small, resting, primed lymphocytes. In vitro primed lymphocytes displayed allogenic memory. This was characteristic of a secondary response, which is shown by the following: 1) acceleration, the peak of thymidine incorporation occurring on day 4,2) specificity, the accelerated response was observed only when the primed lymphocytes were confronted with the cell used for priming. Contact with a third party cell did not produce this kind of activation. 3) Amplitude; the peak DNA synthesis response was greater than that of unprimed lymphocytes cultivated for the same length of time.

Cell Survival↗
PubMed1978

[In vitro stimulation of peripheral blood lymphocytes with allogeneic lymphocytes (mixed lymphocyte culture, MLC) or phytomitogens in patients with Hashimoto's thyroiditis (author's transl)].

To investigate the role of peripheral blood lymphocytes in thyroid auto-immunity, the in vitro responsiveness to allogeneic lymphocytes (MLC) or phytomitogens was examined in the lymphocytes from patients with Hashimoto's thyroiditis. The MLC responses of 16 patients were compared with those of age- and sex-matched normal controls. All possible combinations between lymphocytes from the patients and controls were mixed in both one-way and two-way MLC. From the results of one-way MLC, the stimulatory capacity and responding capacity of lymphocytes from the patients and controls were calculated respectively as follows: : formula: (see text) To the same allogeneic stimulation of Nm (mitomycin-treated stimulating lymphocytes from controls), lymphocytes from the patients (H) exhibited a lower response (P greater than 0.05) than did those from the controls (compare (1) with (3)). Phytomitogen-response was simultaneously studied for residual cells of MLC. Lymphocytes from the patients showed a significantly decreased (P less than 0.01) response to phytohemagglutinin-p and concanavalin A in comparison with the response of normal lymphocytes. From these results, it was suggested that cell-mediated immunity in vivo was impaired in Hishimoto's thyroiditis.

Adolescent↗
PubMed1976

Recruitment of effector lymphocytes by initiator lymphocytes. In vivo migration of in vitro sensitized initiator T lymphocytes.

We previously found that mouse T lymphocytes sensitized in vitro against allo- or syngeneic fibroblasts, upon injection into syngeneic recipients, do not themselves differentiate into effector cells, but recruit effector T lymphocytes within the draining lymph nodes. As a result of sensitization, these initiator lymphocytes acquire a trypsin-sensitive membrane property which is necessary for recruitment. We now report studies on the in vivo migratory behavior of initiator lymphocytes following sensitization. We injected 51Cr-labeled initiator lymphocytes into recipient footpads and found significantly increased migration of sensitized cells to the draining popliteal lymph node (PLN) during the first day. By amputation of the foot at various times, we showed that migration during the first 12-24 hours was critical for subsequent recruitment. Trypsin treatment of initiator lymphocytes abolished this accelerated migration. Lymphocytes triggered nonspecifically by Con A migrated to the PLN like antigen-sensitized cells. We also compared the migration of injected lymphocytes from the footpad to the PLN in graft-versus-host and host-versus-graft reactions, and found these reactions to differ both from each other and from recruitment in terms of lymphocyte migration. These findings are discussed in terms of the physiology of the cell-mediated immune response and the notion of peripheral sensitization.

Animals↗
PubMed1978

The effect of sera from chronic lymphocytic leukemia patients on normal mitogen-stimulated lymphocytes. A possible correlation with the patients' T and B lymphocytes.

Serum from chronic lymphocytic leukemia (CLL) patients was examined for its effect on normal lymphocytes stimulated by phytohemagglutinin and pokeweed. Responses of the patients' lymphocytes were similarly examined. E and EAC rosettes were also tested. A significantly increased transformation response was found when normal lymphocytes were exposed to sera from those patients who had a reduced number of E-rosette-forming lymphocytes (mean 8%) as compared to the response to sera from patients with a higher number of E-rosette-forming cells. The results suggest that a factor is present in sera from some CLL patients which stimulates the transformation of mitogen-stimulated lymphocytes and which seems to be related to the number of the patient's T and B lymphocytes and perhaps with a T suppressor effect on B lymphocytes.

Aged↗
PubMed1979

Regulatory functions of hapten-reactive helper and suppressor T lymphocytes. III. Amplification of a generation of tumor-specific killer T-lymphocyte activities by suppressor T-cell-depleted hapten-reactive T lymphocytes.

2,4.6-trinitrophenyl (TNP)-reactive T-cell activities were raised in mice by immunization with TNP-isologous mouse gamma globulin. After establishing that TNP-reactive T lymphocytes can serve as amplifier cells for induction of killer T lymphocytes in allogeneic system, we explored the possibility of this hapten-reactive T-cell system to amplify tumor-specific killer T-lymphocyte activity in the syngeneic system. We utlized relatively weak immunogenic syngeneic plasmacytoma X5563 in C3H/He mice. Analysis of the TNP-reactive T-cell activities revealed that such T lymphocytes express the biological functions of both major subtypes of regulatory T cells, namely suppressors and helpers, and that TNP-reactive suppressor and helper T lymphocytes, respectively, differ in their relative susceptibility to specific inactivation by TNP conjugates of the nonimmunogenic D-amino acid copolymer, D-glutamic acid, and D-lysine (D-GL). By taking advantage of the relative susceptibility-difference to TNP-D-GL, selective inactivation of TNP-reactive suppressor T cells was induced by appropriate treatment with TNP-D-GL, and the generation of TNP-reactive helper T-cell activity was amplified. The supplement of augmented TNP-reactive helper T-cell activity to the system at the immunization with syngeneic X5563 with TNP-haptenation, resulted in a striking augmentation of induction of tumor-specific killer T-lymphocyte activity, and a considerable number of hosts survived after the challenge with lethal dose of viable tumor cells. Thus, appropriate manipulations designed to induce potent hapten-reactive helper T-lymphocytes provided the potential for a very effective mode of immunoprophylaxis against tumor.

Animals↗
PubMed1978

Effect of released lymphocyte proteins on human lymphocytes in vitro. II. Protein synthesis of nylon-wool separated cells in the presence of proteins derived from lymphocytes.

Protein synthesis of nylon-wool adherent (B) and non-adherent (T) human tonsillar lymphocytes was examined in the presence of three protein fractions precipitated with ammonium sulfate from the medium of the above lymphocytes incubated in vitro for 4 hours. One fraction precipitated with ammonium sulfate at 0--30% saturation was found to inhibit amino acid incorporation into proteins mainly in unseparated cells while the fraction precipitated at 30--70% saturation decreased the rate of protein synthesis in B cells. The fraction precipitated at 70--100% saturation inhibited protein synthesis slightly in T lymphocytes. Protein synthesis in B and T as well as in unseparated cells was also examined in the presence of proteins obtained from the medium of B and T lymphocytes. It is assumed that proteins released by lymphocytes without mitogenic activation in vitro are involved in the mediation of lymphocyte interactions and may be related to lymphokines synthesized and released by activated cells.

B-Lymphocytes↗
PubMed1977

Murine B lymphocyte heterogeneity: distribution of complement receptor-bearing and minor lymphocyte-stimulating B lymphocytes among cells with different densities of total surface Ig and IgM.

The distribution of complement receptor-bearing (CR+) and minor lymphocyte-stimulating (Mls)-defined lymphocyte-activating determinants (LAD) among B lymphocytes with different densities of total surface immunoglobulin (sIg) and sIgM was determined. B lymphocytes that bore intermediate densities of sIg and low densities of sIgM had the highest frequency of CR+ cells and were the most active in expressing Mls-defined LAD. The distribution of these and other surface markers on B-lymphocyte subpopulations is discussed.

Animals↗
PubMed1976

Comparison of normal and chronic lymphocytic leukemia lymphocyte surface Ig determinants using peroxidase-labeled antibodies. II. quantification of light chain determinants in atypical lymphocytic leukemia.

Five cases of atypical lymphocytic leukemia were investigated with regard to their membrane-associated light chains. Detection and quantitation of antigenic determinants were performed by means of peroxidase-labeled antibodies according to Avrameas et al. The cases studied had clinical and cytologic features in common: an active clinical course, marked splenomegaly, severe anemia and thrombocytopenia, little or no lymph node enlargement, and very high white blood counts with small mature lymphocytes and poorly differentiated lymphoid cells. Blood lymphocytes of all patients carried a single type of light chain, and 90%-100% of the cells were stained. The average number of antigenic sites per cell was 72,500 (range 40,000-97,500). These results differed from those previously found in typical CLL (mean value 9000) and approached the values of normal peripheral blood lymphocytes (90,000). The criteria investigated in this study could be of value for the diagnosis and prognosis of some atypical forms of lymphocytic leukemia.

Aged↗
PubMed1978

In vitro effect of transfer factor on the cyclic nucleotide level of human lymphocytes in chronic lymphocytic leukaemia and of mouse lymphocytes.

In the present study transfer factor (TF) failed to produce any change in the cAMP- and cGMP-levels of lymphocytes of patients with chronic lymphoid leukaemia (CLL). This is attributed to the malignant transformation of the lymphocytes or to a changed proportion of different lymphocyte populations in CLL. Human TF leaves the cyclic nucleotide levels of splenic lymphocytes of BALB/c mice unaffected.

Animals↗
PubMed1979

Ultraviolet-induced DNA excision repair in human B and T lymphocytes. III. Repair in lymphocytes from chronic lymphocytic leukaemia.

There have been conflicting reports about the capacity of lymphocytes from individuals with chronic lymphocytic leukaemia (CLL) to undertake u.v.-induced DNA repair. We have examined repair in CLL cells and in control and age-matched purified B and T lymphocytes by a technique independent of incorporation of radioactive precursor, i.e. by the recovery of normal sedimentation behaviour of nucleoid bodies obtained from these cells by lysis in high salt and non-ionic detergent. Recovery of normal sedimentation is associated with restoration of DNA supercoiling. CLL cells were found to be as sensitive to u.v. and to repair at similar rates as age-matched B controls. They are considerably more sensitive than young B cells and repair less efficiently. Reasons for the reported discrepancies in CLL repair are discussed.

Aged↗
PubMed1979

Nonspecific activation of murine lymphocytes. VI. Mediation of synergistic interaction between T and B lymphocytes by a cell-associated, reciprocally acting lymphocyte proliferation helper.

The mechanism by which B and T lymphocytes interact synergistically in the proliferative response to 2-mercaptoethanol (2-ME) as a mitogen was investigated in cultures of C3H/St spleen cells. The interaction between these cells required physical contact between the collaborating cell types, and was not mediated by the release of a soluble factor into the culture supernate. Sonicates of spleen cells which had been activated with optimal concentrations of 2-ME for 24 h and then washed extensively, stimulated the uptake of tritiated thymidine and morphological blast transformation of fresh, unstimulated cells. This activity was found to reside within the soluble fraction of the activated cells, and to activate cells optimally at a ratio of 1 naive cell: 1 activated cell-equivalent. This reciprocally-acting lymphocyte proliferation helper (RALPH) activity was produced by B cells as well as by T cells, with a kinetic peak at 48 h of culture. RALPH activity was produced by viable but not by nonviable cells incubated with 2-ME, and was nondialyzable. It could not be induced by the B-cell mitogens lipopolysaccharide, polyinosinic-polycytidilic acid, or purified protein derivative of tuberculin, or by the T-cell mitogen concanavalin A. RALPH isolated from T cells activated B cells exclusively, while that from B cells acted predominantly upon T cells, possibly with a nonspecific effect on B cells. A model for the cellular interactions involved in the amplification of the proliferative response to 2-ME is described.

Animals↗
PubMed1978

Visualization of tubulin in lymphocytes. I. Comparison of normal and chronic lymphocytic leukemia (CLL) lymphocytes.

Cell structures containing tubulin were studied in peripheral blood lymphocytes from 8 normal donors and 11 patients with CLL using specific antitubulin antibodies revealed by immunoperoxidase assay. The centriole and microtubules were clearly visible in both groups. A "nucleus-associated tubulin-containing structure" was revealed by antitubulin antibodies and was found in virtually all lymphocytes of normal subjects but in a considerably lower number of CLL lymphocytes. The nature of this structure and its relationship to other cell structures are discussed.

Adult↗
PubMed1976

The Fc receptor on thymus-derived lymphocytes. III. Mixed lymphocyte reactivity and cell-mediated lympholytic activity of Fc- and Fc+ T lymphocytes.

The involvement of Fc- and Fc+ T cells, separated on the fluorescence-activated cell sorter, in proliferative and cytotoxic responses to alloantigens was examined. The cytotoxic lymphocytes generated by in vivo exposure to allogeneic tumor cells were shown to express the Fc receptor. The proliferative responses to alloantigen exposure in mixed lymphocyte cultures was equivalent in intensity for unseparated T cells, the Fc+ T-cell fraction, and the Fc- T-cell fraction isolated from nonsensitized spleen cells. In contrast, the cytotoxic responses generated by the Fc- T-cell fraction (less than 1% Fc+) were much weaker than the cytotoxic responses generated by the Fc+ T-cell fraction (80-90% Fc+), and the responses of the Fc+ T-cell fraction were generally weaker than, or equal to the responses of unseparated T cells (Fc- T less than Fc+ T less than or equal to unseparated T). Mixtures of the Fc- and Fc+ T-cell fractions mounted stronger cytotoxic responses than the sum of the responses of either fraction alone. Examination of the Ly phenotypes of the synergizing populations revealed that the CL precursor activity (Ly-2+ T cells) resided in the Fc- T-cell population, and that the amplifier T-cell activity (Ly-1+ T cells) resided in the Fc+ T-cell population. The data are discussed in terms of T-cell heterogeneity, differentiation, and intercellular interaction.

Animals↗
PubMed1976

Generation of cytolytic T lymphocytes in vitro. VIII. failure of anti-RS antisera to inhibit the generation of cytolytic T lymphocytes or cytolytic T lymphocyte activity.

Antibody reactive with "recognition structures" (RS) of mouse lymphoid cells for alloantigens (anti-RS) was prepared by immunization of F1 hybrid mice with parentalstrain lymphoid cells or with antibody produced in one parental strain against alloantigens of the other parental strain. Such antisera prevented generation of the "product of antigenic recognition" (PAR) that is produced within a few hours in cultures prepared with a mixture of lymphoid cells from genetically disparate mice. However, treatment of responding lymphoid cells with anti-RS sera and complement did not inhibit generation of cytolytic T lymphocytes (CTL) in mixed lymphocyte cultures (MLC). Treatment of cells obtained from MLC with anti-RS sera and complement failed to inhibit cytolytic activity of such cells for specific alloantigens.

Animals↗