bluuebunny/crossref_metadata_2025_split huggingface dataset:
Lack of adenosine deaminase activity in cultured murine cytotoxic T lymphocytes.
Authors: Minkowski M D , Castellazzi M , Buttin G 
Published: December 2022

Abstract
The level of adenosine deaminase (ADA) activity was investigated in various populations of IL 2-dependent, cultured cytotoxic T lymphocytes (CTL), from bulk cultures as well as from CTL lines (CTL-A and CTL-B types). The study of C57BL/6 derived, cytotoxic bulk cultures yielded the following mean values of ADA activity: 12,500 U/mg in the cortical, immature region of the thymus, 1500 U/mg in the immunocompetent, cortisone-resistant medullary thymocytes, and 2000 U/mg in the T cell population from the spleen. These results are in agreement with previous studies on separated T lymphocyte populations of known origin and further indicate that a fall in ADA activity accompanies T cell maturation. ADA activity was measured in C57BL/6-derived CTL-A lines obtained from the thymic and splenic bulk cultures. All lines were characterized by a very low level of ADA activity, compared with the T cell bulk cultures freshly initiated from the thymic medulla or from the spleen, and to a variety of T tumor lines established in long term culture. Some showed undetectable ADA activity (less than or equal to 20 units/mg), whereas others maintained significant activity (50 to 500 U/mg). No correlation was found between the residual ADA activity level and the killing activity, at the time of the enzyme assay. Identical properties were observed for CTL-B cloned lines of various genetic backgrounds. These results suggest that the level of ADA activity of the CTL in the mouse is lower than the average value of mature T cells of the thymic medulla, and might constitute a differentiation marker specific to the CTL population. A possibility remains that low ADA activity levels in these CTL lines may be the consequence of an extinction of the ADA gene during in vitro growth, as it is observed for the cytotoxic activity itself. In either case, a low ADA activity level is a remarkable property of IL 2-dependent CTL clones, when compared to various established T tumor lines, which exhibit high and stable ADA levels during long term in vitro growth (5000 to 15,000 U/mg).
Pre-B cells in mouse bone marrow: in vitro maturation of peanut agglutinin binding B lymphocyte precursors separated from bone marrow by fluorescence-activated cell sorting.
Authors: Osmond D G , Melchers F , Paige C J 
Published: December 2022

Abstract
Peanut agglutinin (PNA) binding by mouse bone marrow cells and fractionation by the fluorescence-activated cell sorter have previously been shown to separate high concentrations of pre-B cells, as identified by cytoplasmic mu-chains (c mu). PNA+ and PNA- marrow cell fractions have now been assayed for the presence of functional pre-B cells able to generate mature B cells in culture, as defined by three criteria, the appearance of cell surface mu-chains (s mu), immunoglobulin secretion in response to bacterial lipopolysaccharides, and B cell colony formation. Small PNA+ cell fractions contained pre-B cells that developed into mature B lymphocytes in 1/2 to 1 day but did not sustain B cell production. Large PNA+ cells included pre-B cells that gave rise to mature B lymphocytes after an interval of 1 1/2 to 3 days and were able to sustain B cell genesis in vitro for at least 3 to 5 days thereafter. PNA- cell fractions contained mature B cells but lacked pre-B cell activity. The results demonstrate that PNA binding allows the separation of functional subsets of pre-B cells from bone marrow and that the three in vitro assays used in this study are closely comparable with one another as functional pre-B cell criteria. The findings suggest correlations between functional assays, c mu expression, PNA receptors, and cell size in characterizing stages of pre-B cell development.
Molecular genetic analysis of genes encoding the heavy chains of rabbit IgG.
Authors: Martens C L , Currier S J , Knight K L 
Published: December 2022

Abstract
We analyzed the genes which encode the heavy chain constant region of rabbit IgG molecules. Five DNA clones derived from the chromosomal region which spans the C gamma coding sequences were isolated from a recombinant phage library of rabbit liver DNA. Four of these clones can be grouped together by overlaps; together they represent 37 kb of genomic DNA, and contain one C gamma gene and one tentatively identified C epsilon gene. A second C gamma gene was identified which did not overlap with the group of four clones because of restriction site differences found in the flanking regions 5' to the C gamma genes. Nucleotide sequences of the two C gamma genes were identical. Comparisons of the restriction maps of the two cloned C gamma genomic regions suggest that they may represent allelic regions of chromosomes of two different heavy chain haplotypes with polymorphisms in the regions flanking the C gamma genes.
Specific cytolysis of fresh tumor cells by an autologous killer T cell line derived from an adult T cell leukemia/lymphoma patient.
Authors: Kannagi M , Sugamura K , Kinoshita K , Uchino H , Hinuma Y 
Published: December 2022

Abstract
Cytotoxic T cells (Tc) derived from one patient with adult T cell leukemia/lymphoma (ATL) killed fresh autologous lymphoma cells in vitro. The Tc were induced from peripheral blood leukocytes (PBL) of this patient during remission by multiple in vitro stimulations with an autologous ATLV-bearing cell line (ILT) that was previously established by cloning of PBL in the presence of interleukin 2 (IL 2). PBL from eight other ATL patients were stimulated in the same manner, and responder cells from a patient in remission also showed cytotoxicity specific for ATL virus (ATLV)-bearing cells. Fresh lymphoma cells were obtained in relapse and were used as target cells for the autologous Tc induced. They became susceptible to the Tc within 4 hr of in vitro incubation, and their susceptibility increased with incubation time for at least 12 hr. ATLV antigens on the cell surface of these lymphoma cells, however, were not detected by radioimmunoassay during these incubation periods, but were detectable after 16 hr of incubation. In addition, cytotoxicity against lymphoma cells was completely inhibited by autologous ILT cells used as "cold" target competitor cells. These findings indicate that the target antigen of the Tc was expressed on both autologous ILT cells and lymphoma cells, and it may be different from ATLV antigens detected by serologic methods. In addition, the data suggested allogeneic restriction of the Tc in that the preferentially killed allogeneic ATLV-bearing cells share several HLA antigens.
Regulation of the immune response to tumor antigens. X. Activation of third-order suppressor T cells that abrogate anti-tumor immune responses.
Authors: Schatten S , Drebin J A , Perry L L , Chung W , Greene M I 
Published: December 2022

Abstract
The experiments described further define the suppressor T cell pathway in the S1509a tumor system. We demonstrated previously that S1509a-induced Ts1, TsF1, and Ts2 specifically suppress in vivo Ly1+2- T cell-dependent responses to S1509a and that Ts1 suppress in vivo Ly-1+2- T cell-mediated proliferative responses to S1509a. We have now shown that in vivo administration of either S1509a-induced TsF1 or TsF2 suppresses both in vivo and in vitro Ly-1+2- T cell-mediated responses to S1509a. Furthermore, we revealed the existence of Ts3, which are activated by S1509a tumor antigen and TsF2, in this murine tumor system. Finally, we demonstrated that cyclophosphamide abrogates the suppressive effect of TsF2 but not that of Ts3. These results are discussed with respect to T cell-mediated suppression in other murine tumor systems and the possible pivotal role for a tumor antigen-presenting cell in activating Ts3 in the S1509a tumor system.
Human newborn autologous mixed lymphocyte response: frequency and phenotype of responders and xenoantigen specificity.
Authors: Hayward A R , Mori M 
Published: December 2022

Abstract
The response of human newborn lymphocytes in autologous mixed lymphocyte culture was examined for specificity (by restimulation), responder cell phenotype, and responder cell frequency. When the newborn T cells were separated from non-T cells by rosetting with sheep erythrocytes (E) in fetal calf serum (FCS), approximately 1:20,000 T cells proliferated. These responders had specificity for E + FCS, were T4+, and were self-restricted. Significant numbers of responder T cells were not found when newborn T and non-T cells were separated by nylon wool. Responses in parallel autologous cultures of adult T cells showed that 1) adults had a higher frequency than newborns of E + FCS specific responders, 2) evidence for self specificity was lacking in restimulated cultures, and 3) occasional responses to antigen on the surface of monocytes could not be excluded.
Interferon is the suppressor of hematopoiesis generated by stimulated lymphocytes in vitro.
Authors: Zoumbos N C , Djeu J Y , Young N S 
Published: December 2022

Abstract
Lymphocytes that inhibit hematopoiesis may have a pathogenic role in some forms of bone marrow failure, and lymphocyte-mediated suppression may also be important in the normal regulation of bone marrow function. We have investigated the mechanism of in vitro suppression of hematopoiesis by T cells by using the methylcellulose colony culture system. Total peripheral blood T cells and separated subpopulations of helper (OKT4+) and suppressor (OKT8+) cells that have been stimulated by exposure to lectin suppress autologous colony formation by bone marrow myeloid (CFU-C) and erythroid (BFU-E) progenitor cells. Medium conditioned by these cells is also inhibitory, indicating that the suppressor activity is a soluble factor. A strong correlation existed for the concentration of interferon and the degree of hematopoietic suppressor activity in these supernatants; both activities peaked at days 3 to 5 of incubation and had sharply declined by day 7. Interferon production was enhanced by exposure of lymphocytes to sheep red blood cells during the rosetting procedure. Specific antiserum and a monoclonal antibody directed against gamma-(immune) interferon abrogated the inhibitory activity for hematopoiesis produced by lectin-stimulated T cells; an antiserum to alpha-interferon was generally much less effective in neutralizing activity. We infer from these results that gamma-interferon is the mediator of hematopoietic suppression generated by lectin-treated T-cells.
A new lymphocyte surface antigen defined by a monoclonal antibody (9F3) to the T cell population expanding in MRL/Mp-lpr/lpr mice.
Authors: Dumont F J , Habbersett R C , Nichols E A 
Published: December 2022

Abstract
This report is a description of the pattern of reactivity of a rat monoclonal antibody (MAb 9F3) directed to the abnormal T cells expanding in MRL/Mp-lpr/lpr (MRL/lpr) mice. By using single- and two-color flow cytofluorometry analysis, this MAb was found to stain brightly 90 to 98% of lymph node (LN) T cells from MRL/lpr, C57BL/6-lpr/lpr (B6/lpr), and C3H/HeJ-lpr/lpr mice, and approximately 10 to 50 times less intensely 55 to 70% of T cells from control congenic +/+ mice. The study of in vitro proliferative responses of sorted cells from MRL/+ mice demonstrated that 9F3- T cells react better to phytohemagglutinin and allogeneic cells but less well to concanavalin A (Con A) than 9F3+ T cells. Upon Con A-induced blastogenesis, 65% of 9F3- T cells became 9F3+ whereas all 9F3+ remained 9F3+. Although only 15% of thymocytes, which included hydrocortisone-resistant population, were 9F3+ in +/+ mice, up to 60% of bright 9F3+ cells were detectable in the thymus of lpr-bearing mice after the onset of lymphoproliferation. Moreover, in both lpr-bearing and normal mice, the 9F3 MAb stained the totality of resting or mitogen-activated B cells. The 9F3 MAb also reacted with 100% of bone marrow (BM) cells, irrespective of the lpr gene. However, a subset of bright 9F3+, large BM cells was increased in frequency in lpr-bearing mice compared to congenic controls. Although expressed on macrophages, granulocytes, and erythrocytes, the 9F3 antigen was not in liver, kidney, and brain tissue of MRL/+ mice. Because the cell and tissue distributions of the 9F3 antigen do not correspond to any previously described murine antigen, this antigen may represent a new surface marker that should prove useful for studying lymphohemopoietic cell differentiation in normal and lpr-bearing mice.
Glycolipid antigens with blood group I and i specificities from human adult and umbilical cord erythrocytes.
Authors: Okada Y , Kannagi R , Levery S B , Hakomori S 
Published: December 2022

Abstract
Neutral glycolipids and gangliosides of umbilical cord and adult human erythrocytes were separated by high performance liquid chromatography, and each fraction was analyzed by direct binding of anti-I (Ma) and anti-i (Den) on solid phase glycolipid-lecithin-cholesterol. The I- and i-active glycolipids were isolated and their structures were determined by methylation analysis and direct probe mass spectrometry. The major I antigen in adult erythrocytes, showing a remarkable binding activity with anti-I(Ma), was found in one neutral glycolipid fraction, designated fraction y4, which was identified as a mixture of two glycolipids of a new type, lactoisooctaosylceramide and monofucosyllactoisooctaosylceramide (for structures, see Table I). In addition, two gangliosides displaying direct binding activity with anti-I(Ma) were identified as monosialoganglioside G8, as previously described and disialosyllactoisooctaosylceramide, which showed the same level of I activity as the y4 glycolipid. The same ganglioside was recently isolated and characterized by Kundu and co-workers. The major i-active glycolipid antigen in umbilical cord erythrocytes, showing a strong binding activity with anti-i(Den), was a neutral glycolipid, x4a, which was identified as lactonorhexaosylceramide. This glycolipid without fucosyl or sialosyl substitution has not been isolated previously and was present as an obvious normal component of umbilical cord erythrocytes, but an extremely minor component of adult erythrocytes. Sialosyllactonorhexaosylceramide (G6) was isolated and characterized as a second i antigen of umbilical cord erythrocytes, but showed a very weak binding activity with the anti-i antibody. Although these sialosyl derivatives displayed only weak activity, the chemical quantity of the sialosyl derivatives is significantly large in fetal erythrocytes; therefore, Ii activity of human erythrocytes, in general, must be significantly dependent on sialosyl derivatives in addition to unsubstituted structures.
Modification of cellular protein sulfhydryl groups by activated soluble immune response suppressor.
Authors: Aune T M 
Published: December 2022

Abstract
Soluble immune response suppressor (SIRS), a product of murine Ly-2+ T lymphocytes, is activated to SIRSox by H2O2 produced by macrophages: SIRSox directly inhibits cell division by normal and neoplastic cells and antibody secretion by B lymphocytes. To examine the mechanism of SIRSox-mediated inhibition, a variety of cellular functions were measured after treatment of cells with SIRSox. These included respiration, glucose transport, microtubule content, glutathione content, production of H2O2 or superoxide anion, and the activities of a variety of different enzymes. Several cellular activities or measurements were inhibited or lowered after SIRSox-treatment, including cell division, microtubule content, glutathione reductase activity, and thioredoxin reductase activity; inhibition was partially reversed by the sulfhydryl reducing agent dithiothreitol. Protein sulfhydryl content of P815 mastocytoma cells and several other cell types was lowered by 35 to 45% after exposure to SIRSox. Protein sulfhydryl loss was also partially restored after incubation with dithiothreitol. Sulfhydryl loss was not due to cell lysis. In addition, treatment of crude cellular particulate fractions with SIRSox resulted in protein sulfhydryl loss and formation of protein sulfenyl derivatives. A comparison of the amount of SIRS and H2O2 present to the number of protein sulfhydryls lost or sulfenyl derivatives formed suggests that SIRSox acts catalytically, serves as a co-factor in protein sulfhydryl oxidation, or that it activates a second pathway that is directly responsible for sulfhydryl oxidation.
Adenosine receptors on mouse bone marrow-derived mast cells: functional significance and regulation by aminophylline.
Authors: Marquardt D L , Walker L L , Wasserman S I 
Published: December 2022

Abstract
Adenosine receptors on mouse bone marrow-derived mast cells were identified by functional criteria and radioligand binding. The stimulated release of beta-hexosaminidase from these cells was significantly augmented by the simultaneous addition of secretagogue and adenosine, NECA, or L-PIA. Similar enhancement of pre-formed mediator release occurred after a 10-min preincubation with adenosine. Resting mast cell cAMP levels increased within 15 sec after the addition of adenosine, and remained elevated for at least 60 sec. Although the antigen-or A23187-induced release of beta-hexosaminidase was markedly potentiated by exogenous adenosine, the stimulated release of [14C]-labeled arachidonic acid metabolites was minimally affected by adenosine, suggesting a differential effect of adenosine on granule-associated release as compared to generated mediator release. Bone marrow mast cells exhibited 5470 +/- 740 [3H]adenosine binding sites/cell, with a binding affinity of 24.4 +/- 3.8 nM. Cells cultured in the presence of 100 microM aminophylline for 6 days were hyperresponsive to exogenous adenosine, releasing a maximum of 162% of the amount of beta-hexosaminidase released from control cells in the presence of adenosine. The number of [3H]adenosine binding sites on the xanthine-treated cells increased to 156% of control values, suggesting an up-regulation of adenosine receptors induced by chronic exposure to an adenosine receptor antagonist. Mouse bone marrow mast cells possess functionally significant adenosine receptors that are regulated by aminophylline and that, when stimulated, produce many alterations in the mast cell secretory process.
The synergistic anti-proliferative effect of gamma-interferon and human lymphotoxin.
Authors: Lee S H , Aggarwal B B , Rinderknecht E , Assisi F , Chiu H 
Published: December 2022

Abstract
Highly purified preparations of rHuIFN-gamma and HLT synergistically inhibit the in vitro proliferation of WI38VA13 cells, a SV40 virus-transformed derivative of the human cell line W138. The growth of nontumorigenic WI38 cells, established from normal diploid embryonic lung tissue, was not inhibited under identical incubation conditions; rMuIFN-gamma and HLT have the same in vitro effects on the murine melanoma B16. Thus, the combination of rMuIFN-gamma and HLT synergistically inhibits the growth of B16 cells, although incubation with either lymphokine alone has no significant anti-proliferative effect. Flow cytometric analysis of the cell cycle of asynchronous cells indicates that when B16 melanoma cells are treated with rMuIFN-gamma and HLT in combination, more cells accumulate in the G0/G1 phase than when the cells are treated with rMuIFN-gamma alone. It appears that populations of rapidly proliferating tumor cells, which normally contain a large percentage in the S+G2+M phases of the cell cycle, become arrested in the quiescent G0/G1 phase by the combination of IFN-gamma and HLT, resulting in the inhibition of cell growth.
Inhibition of human B cell activation by diterpine forskolin: interference with B cell growth factor-induced G1 to S transition of the B cell cycle.
Authors: Muraguchi A , Miyazaki K , Kehrl J H , Fauci A S 
Published: December 2022

Abstract
We have previously demonstrated that a series of sequential steps are involved in the induction of a resting human B cell to proliferate. In this system, initial activation signals were delivered by either in vivo or in vitro stimulation, and proliferative signals were delivered by a B cell growth factor (BCGF) that was derived from a human T-T cell hybridoma. The involvement of adenosine 3',5'-monophosphate (cAMP) in regulating the growth and differentiation of lymphocytes has been of considerable interest. Diterpine forskolin has been reported to be a unique adenylate cyclase activator in membranes from mammalian tissues that results in elevations of intracytoplasmic cAMP. We have examined the effect of this drug on the progression of human B cells through their activation cycle. It was found that forskolin causes a rapid and sustained increase of cytoplasmic cAMP in purified small and large B cells. In the in vitro costimulation of small resting B cells with anti-mu plus BCGF, forskolin inhibited the proliferative response of B cells in a dose-dependent manner. This forskolin-mediated suppression of B cell proliferation was found when the drug was added to the cultures as late as 36 hr after initial stimulation. Of note is the fact that the anti-mu-induced RNA synthesis as well as cell enlargement in resting B cells was not inhibited by the addition of forskolin, whereas BCGF-induced proliferative response of activated B cells was markedly inhibited by the drug. Thus, these data demonstrate that forskolin, an agent that elevates cytoplasmic cAMP levels, has relatively little effect on early events in the human B cell cycle (G0 to G1) transition, but selectively inhibits the progression of BCGF-induced G1 to S phase transition of B cells.
Thymocyte differentiation activity from the cloned monocyte/macrophage cell line RAW 264.7. Alterations in the expression of immature thymocyte surface antigens.
Authors: McKernan L N , Largen M T 
Published: December 2022

Abstract
The cloned monocyte/macrophage cell line RAW 264.7 was previously shown to produce thymocyte mitogenic and co-mitogenic activity that eluted from a Sephadex G-75 column not only at approximately 16,000 daltons, the m.w. described for interleukin 1 (IL 1), but also at 30,000 to 40,000 daltons. The studies reported here indicate that the 30,000 to 40,000 dalton molecule has thymic differentiating activity. Thymocytes from A/J mice were fractionated on discontinuous BSA gradients, which yielded populations of cells enriched for immature and mature cells. The cells found at the interface between 35 and 29% BSA (band 1 cells), which are the most immature, were cultured for 48 hr with highly purified IL 1, with the 30,000 to 40,000 dalton form of thymocyte co-mitogenic activity obtained after Sephadex G-75 chromatography and chromatofocusing chromatography, or with media alone. The surface antigens TL-3, H-2Kk, Thy-1.2, Lyt-1, and Lyt-2 were examined by immunofluorescence. It was found that the highly purified 30,000 to 40,000 dalton species of co-mitogenic activity induced a significant increase in the content of surface H-2Kk, a decrease in TL-3, and a very small decrease in Thy-1.2 on the cell surface, whereas IL 1 was not capable of inducing a change in these surface antigens. There was no change in Lyt-1 on the surface of band 1 thymocytes after incubation with either IL 1 or the 30,000 to 40,000 dalton species. The 30,000 to 40,000 dalton species caused a significant decrease in the percentage of cells staining positive for Lyt-2, whereas IL 1 caused a smaller but significant decrease in Lyt-2. These changes in the surface markers TL-3, H-2Kk, and Thy-1.2 are consistent with changes that occur during thymocyte differentiation. It was also observed that the proliferative response to the 30,000 to 40,000 dalton form and IL 1 increased with increasing functional maturity of each band of thymocytes when used in the thymocyte mitogenic assay. However, only the 30,000 to 40,000 dalton form was capable of inducing a proliferative response in the immature band 1 thymocytes in the thymocyte co-mitogenic assay. These results indicate that the RAW 264.7 cells produce a factor that has, in addition to thymocyte co-mitogenic activity, thymocyte differentiation activity, and this factor is distinct from IL 1.