bluuebunny/crossref_metadata_2025_split huggingface dataset:
Antigen-Initiated B Lymphocyte Differentiation
Authors: Shortman Ken , Howard Maureen , Teale Judy , Baker Julie 
Published: December 2022

Abstract
Both primary IgM and secondary IgM and IgG adoptive immune responses to the thymus-independent antigen NIP-POL were found to proceed in two stages. The first 3 to 4 days of these responses required a stimulus, but this could be provided by an unrelated antigen such as HRC. Only the second 3- to 4-day stage of the response, leading to an AFC peak at day 8, required the specific antigen NIP-POL. This novel priming schedule of nonspecific followed by specific antigenic stimulation in fact produced a significantly greater AFC response than the standard specific immunization procedure. With the schedule of nonspecific, then specific antigen injection, the primary IgM response was T cell independent. Two sequential injections of specific antigen also gave an elevated adoptive response from the same B cell subset, but this time the increased component of the response was T cell dependent.
The results corroborate earlier work, and support a model of two sequentially related and “antigen”-responsive subsets of both primary and secondary B cells, termed “pre-progenitors” and “direct AFC progenitors”. Responses to antigens are thus two-tiered. In the first stage, all “pre-progenitor” subsets are nonspecifically activated to proliferate and differentiate into “direct-progenitor” B cells. This stage is different from “pre-B” to B cell development. Although it may occur continuously at a lower level in normal animals, it requires an environmental or experimentally introduced stimulus, and is probably triggered via macrophage activation. In the second stage the conventional rules apply, and antigens specifically stimulate antigen-restricted clones of direct-progenitor B cells to produce AFC.
Production of Human T Cell Colony-Inducing Activity (TCI) by Malignant Cells from Patients with Lymphocytic and Myeloid Leukemia
Authors: Douer Dan , Sachs Leo 
Published: December 2022

Abstract
Normal peripheral blood lymphocytes can be induced to form T cell colonies in culture by a T cell colony-inducing activity (TCI) found in conditioned medium (CM) induced by phytohemagglutinin (PHA) in normal T lymphocytes. TCI was also found in CM induced by PHA in peripheral blood cells from patients with untreated B cell chronic lymphocyte leukemia (CLL) and untreated acute myeloid leukemia (AML). The CM from these leukemic patients showed a much higher TCI activity for T lymphocytes both from normal persons and from CLL patients, than the CM from normal lymphocytes. This more active TCI was produced in the CLL patients by the peripheral blood B lymphocytes and in the AML patients by the peripheral blood myeloblasts. The CM from normal persons and CLL patients also contained an activity that induced the formation of granulocyte colonies from normal bone marrow cells. Although the CM from CLL showed a higher TCI activity than the CM from normal persons also with normal bone marrow cells, CM from both sources induced a similar number of granulocyte colonies.
The results indicate that malignant B lymphocytes from CLL patients and malignant myeloblasts from AML patients can produce a higher TCI activity than that produced by normal lymphocytes. It is suggested that induction of high TCI activity in certain malignant cells may selectively increase the number of normal T lymphocytes, and that the high TCI activity that can be produced by malignant B cells from CLL patients may explain the higher number of T cells that have been reported in these patients.
Induction of Autoreactive Cells by the Preculture of Human Peripheral Blood Mononuclear Cells with the Autologous Fresh Plasma
Authors: Tomonari Kyuhei , Aizawa Miki 
Published: December 2022

Abstract
An AMLR in which precultured cells proliferated in response to fresh non-T cells is described. In our system, the responder is human peripheral blood mononuclear cells precultured in the autologous fresh plasma for up to 16 days, and the stimulator is fresh autologous non-T cells. Results suggested that there were two subpopulations of autoreactive cells obtained from the preculture; the high and low density small lymphocytes, both having ERF activity. The autoreactivity of low density cells was augmented when either macrophages or N-ERF-cells were depleted from PBM and thereafter precultures were performed. A survey of the functional characteristics of the responding cells showed that the responding cells had NK activity against Molt-4 cells but had no significant ADCC activity against target CRBC. Mechanisms for the induction of autoreactive cells by the preculture in the presence of autologous fresh plasma are discussed.
Characterization of a Circulating Subpopulation of Spontaneous Antitetanus Toxoid Antibody Producing B Cells Following in Vivo Booster Immunization
Authors: Stevens Ronald H. , Macy Eric , Morrow Casey , Saxon Andrew 
Published: December 2022

Abstract
The appearance of circulating B lymphocyte subpopulations responsible for the in vitro synthesis of IgG or IgM antitetanus toxoid antibody after in vivo booster immunization has been analyzed. Before booster immunization, only background levels of IgG antitetanus toxoid antibody were synthesized by B lymphocytes alone, or in combination with T cells and pokeweed mitogen, as measured by quantitative radioimmunoassay. Within 5 days after booster immunization, a population of B lymphocytes appeared within the circulation that had the capacity to synthesize IgG antitetanus toxoid antibody in the absence of T lymphocytes or pokeweed mitogen. These cells could be detected in the circulation until 10 to 12 days after immunization, and the antibody synthesized was inhibited by the inclusion of 50 µg/ml cyclohexamide in the culture medium. At the peak of this response, between 10 and 60% of the total IgG synthesized was IgG directed against tetanus toxoid. The cells responsible had a precursor frequency of up to 10-3 in the non-E-rosetting cell fraction obtained from peripheral blood and sedimented at 1 × G with velocities ranging from 4 to 11 mm/hr. The synthesis of IgM antitetanus toxoid antibody by this cell fraction was not detected.
In contrast to the above B cells, lymphocytes capable of responding to pokeweed mitogen and T lymphocytes with the synthesis of IgG antitetanus toxoid antibody did not appear in the circulation until 10 days after immunization. Limiting dilution analysis of the pokeweed mitogen responsive B lymphocytes 2 to 4 weeks after booster immunization gave a precursor frequency of 1 × 10-4. In the presence of T cells and PWM, the synthesis of IgM anti-Tet remained at constant levels before and for 3 weeks post-booster immunization. These results indicate that multiple subsets of circulating B cells can be functionally defined in humans.
Expression of MHC Antigens by Mouse Thymic Dendritic Cells
Authors: Rouse Robert V. , van Ewijk Willem , Jones Patricia P. , Weissman Irving L. 
Published: December 2022

Abstract
Thymic epithelial cells express MHC antigens in several different patterns. I-A is present throughout the thymic cortex on dendritic cells. The remainder of the I region and H-2K/D are expressed on dendritic cells apparently only variably in the cortex (at least in some haplotypes). All MHC antigens tested are present in the medulla on epithelial cells; expression on medullary lymphocytes cannot be evaluated. Monoclonal anti-MHC antibodies confirm these results. The significance of these findings to T cell maturation is discussed.
Natural Killer Cells, Bone, and the Bone Marrow: Studies in Estrogen-Treated Mice and in Congenitally Osteopetrotic (mi/mi) Mice
Authors: Seaman William E. , Gindhart Thomas D. , Greenspan John S. , Blackman Marcia A. , Talal Norman 
Published: December 2022

Abstract
Mice lose natural killer cells after 6 weeks of treatment with 17β-estradiol. We here demonstrate that the same protocol leads to loss of genetic resistance to bone marrow transplantation and to significant osteoproliferation with loss of bone marrow. We also show that mice with reduced marrow because of congenital osteopetrosis are deficient in natural killing. These findings are consistent with previous evidence that natural killing and genetic resistance to bone marrow transplantation are dependent upon the marrow.
Temporal studies of bone histology and radiology during and after treatment with estrogen reveal that alterations in natural killing proceed more rapidly than changes in bone marrow volume. These studies also demonstrate that estrogens induce osteoproliferation only at endosteal surfaces that are adjacent to hematopoietic marrow. From these observations, we conclude that estrogens do not reduce natural killer cells simply by reducing the volume of bone marrow. Estrogens may instead have an effect on bone marrow cells that leads both to osteoproliferation and to a deficiency of marrow-dependent cells.
T Cell Regulation of Polyclonal B Cell Responsiveness
Authors: Goodman Michael G. , Weigle William O. 
Published: December 2022

Abstract
Polyclonal activation of murine splenic B lymphocytes to secrete immunoglobulin was shown to be subject to regulation by splenic T cells. By admixture of separated B and T cell populations it was demonstrated that normal fresh splenic T cells were able to augment polyclonal B cell responsiveness to LPS up to several-fold. Optimal collaboration between these two cell types ensued when they were co-cultured in equal numbers. T cell-mediated enhancement of polyclonal B cell responses was dependent upon the ability of T cells to divide and was manifested upon T cell interaction with B cells soon after culture initiation. Originally expounded as a one-signal phenomenon, polyclonal activation of lymphocytes by LPS is, under the circumstances described, attributable instead to two distinct, nonspecific signals acting in concert. The observation that T cells from LPS-nonresponder (C3H/HeJ) mice were deficient in the capacity to enhance polyclonal B cell responsiveness of B cells derived from responder (C3H/HeN) mice implied a direct action of LPS on the involved T cells as well as an active role for the T cell signal in this immunoregulatory event. The novel observation of a functional T cell defect in LPS responsiveness in the C3H/HeJ mouse is discussed in terms of its other cellular defects.
Maturation of the Lymphoid System
Authors: Etlinger Howard M. , Chiller Jacques M. 
Published: December 2022

Abstract
A/J mice displayed a striking ontogenetic difference in the capacity to respond to DNP-Ficoll, a T-independent antigen, and to aggregated human γ-globulin (AHGG), a T-dependent antigen. Thus, whereas responses to DNP-Ficoll of 4-day-old mice were similar in magnitude to those of adult animals, responses to AHGG did not become pronounced until mice were some 30 to 40 days of age. The inability of young animals to respond to AHGG was reflective of a negative consequence of lymphocyte/antigen interaction, since such mice became specifically unresponsive to subsequent challenges with AHGG. Unresponsiveness induced by neonatal injection of AHGG lasted 50 to 60 days, in contrast to that induced by deaggregated HGG, which persisted some 100 days longer. The unresponsive state induced by injection of neonates with AHGG maintained itself upon adoptive transfer and did not appear to be linked to suppressive factors associated with either serum or lymphoid cells for its maintenance. Finally, AHGG was also shown to be capable of inducing unresponsiveness in neonatal, athymic mice. These results demonstrate that AHGG, the normally immunogenic form of HGG in adult mice, can serve as an effective tolerogen when administered into a neonatal environment.
Maturation of the Lymphoid System
Authors: Etlinger Howard M. , Chiller Jacques M. 
Published: December 2022

Abstract
It has been previously shown that AHGG, a form of HGG that is highly immunogenic in euthymic adult mice, is capable of inducing specific unresponsiveness when injected into neonatal animals. This report extends this finding and indicates that such a neonatal treatment results in the induction of tolerance in T as well as B cells. Furthermore, a similar conclusion was reached regarding specific T lymphocyte function in animals treated as neonates with OVA. The ability of LPS to modulate responses of neonatal animals to AHGG or DHGG was also examined. It appeared that such mice were not susceptible to the adjuvant effects of LPS until the 4th week of life. Furthermore, LPS was incapable of inhibiting the unresponsiveness induced in mice by either DHGG or AHGG until the 3rd or 4th week of life.
Requirement for a Bacterial Flora before Mice Generate Cells Capable of Mediating the Delayed Hypersensitivity Reaction to Sheep Red Blood Cells
Authors: MacDonald Thomas T. , Carter Philip B. 
Published: December 2022

Abstract
A delayed-type hypersensitivity (DTH) reaction can be elicited by an injection of 108 sheep red blood cells (SRBC) into a rear footpad of conventional (CV) mice previously immunized with small doses of SRBC. In contrast, immunization of germ-free (GF) mice with the same doses of SRBC produced no DTH when immunization was by the intravenous (i.v.) route, and only weak reactions when immunization was by the subcutaneous (footpad) route. Varying the immunizing dose of SRBC, or the time at which DTH was elicited, did not produce a state of DTH responsiveness in i.v. immunized GF mice. However, the transfer of lymphocytes from CV mice, immunized 4 to 5 days previously with SRBC, into GF mice, conferred on GF mice the capacity to express DTH. Although DTH was not readily demonstrable in GF mice immunized with SRBC, they nevertheless produced normal levels of hemagglutinating antibody to SRBC. Finally, it was shown that GF mice could generate a normal DTH response to SRBC if they were first monoassociated with a Gram-negative bacterial flora.
Eosinophil-Mediated Killing of Schistosomula of Schistosoma Mansoni in Vitro: Synergistic Effect of Antibody and Complement
Authors: McLaren Diane J. , Ramalho-Pinto F. J. 
Published: December 2022

Abstract
The capacity of rat peritoneal eosinophils to kill schistosomula of Schistosoma mansoni coated with antibody plus complement (C) (fresh immune rat serum) has been compared with that recorded when the parasites are coated with C alone (fresh normal rat serum) or antibody alone (heat-inactivated immune rat serum). Time course studies of adherence and killing, together with serum and cell dilution experiments, have revealed the superior efficiency of the system involving eosinophils, antibody, and C. Cell migration assays have shown that the combined factors generated when both the classical and alternative C pathways are activated at the parasite surface are more potent eosinophil chemoattractants than those generated from the alternative pathway alone. Moreover, faster and higher levels of eosinophil-mediated killing accompany the generation of such factors; 70 to 80% mortality being recorded within 3 hr as compared to 25% or less when the factors are absent. Experiments with fIRS chelated with EGTA indicate that more C3 molecules are probably bound to the parasite surface when C is activated via the classical rather than the alternative pathway, and that factors stimulating eosinophil migration generated from the classical pathway promote faster adherence and, as a consequence, higher levels of eosinophil-mediated killing. IgE does not seem to play an important role in eosinophil-mediated cytotoxicity in vitro, in the presence of fIRS, but the possible participation of the anaphylatoxins and ECF-A is discussed. It is suggested that the rapid and enhanced parasite killing effected by the combination of eosinophils, antibody, and C may be of paramount importance in the destruction of the schistosomula of a secondary infection in the immune host.
Some Invariant Properties of IgE-Mediated Basophil Activation and Desensitization
Authors: Goldstein Byron , Dembo Micah , Sobotka Anne K. , Lichtenstein Lawrence M. 
Published: December 2022

Abstract
We investigate certain general properties of antigen induced degranulation of sensitized basophils by analyzing two types of experiments: Experiments in which we expose basophils to two antigens sequentially and then determine the fraction of histamine released; and experiments in which we obtain time-dependent release and desensitization curves. To analyze the latter type of experiments we introduce a new way to plot release and desensitization data that depends on the nature of the interactions of histamine-containing units (histamine quanta) with themselves or the cells degranulation apparatus, but not on any specific properties of the antigen.
From our analysis we conclude that: 1) A fraction of histamine within a population of basophils is nonreleasable by antigenic stimulation. 2) When a basophil degranulates the initial release of histamine appears to inhibit subsequent release. 3) The rate of histamine release is proportional to the amount of releasable histamine remaining in the cells when the amount remaining is small, as expected if released of histamine granules is a stochastic process. 4) There is no dependence of desensitization on the extracellular calcium concentration.
Young F1 Mice Spontaneously Generate Cytotoxic T Cells against Parental Targets
Authors: Ishikawa Hiromichi , Dutton Richard W. 
Published: December 2022

Abstract
Spleen cells from young (AKR/J♀ × BALB/c) or (BALB/c♀ × AKR/J)F1 mice can spontaneously generate effector cytotoxic T lymphocytes (CTL), in a 5-day primary in vitro culture, which lyse target cells from AKR/J and BALB/c but not allogeneic mice. These spontaneous CTL responses first appear when spleen cells are taken from F1 mice at 3 to 4 weeks of age, are maximum at about 5 weeks, and have declined by week 7. The fact that these spontaneous CTL responses are never detectable in the spleen cell cultures from any ages of parental AKR/J and BALB/c mice makes them unique properties of the F1 mice.
Surface Ig Isotypes on Cells Responding to Lipopolysaccharide by IgM and IgG Secretion
Authors: Gronowicz Eva Severinson , Doss Carol , Assisi Francis , Vitetta Ellen S. , Coffman Robert L. , Strober Samuel 
Published: December 2022

Abstract
Using the fluorescence-activated cell sorter (FACS), we have investigated the Ig isotypes present on murine B cells, which can be polyclonally activated by lipopolysaccharide (LPS) in low cell density cultures. The LPS response was partly inhibited as a result of staining with anti-IgD and anti-IgM reagents, but not with anti-IgG reagents. The IgM+, IgD+, or IgG- fractionated cell populations gave both an IgM and an IgG response comparable to controls, whereas the response of the IgM-, IgD- cells was 5- to 20-fold lower. IgG- cells separated 1 day after LPS stimulation could still mount an IgM and IgG response indistinguishable from controls at the peak of the response. It is concluded that IgM+, IgD+, IgG- cells constitute the major LPS-sensitive cell population in the low cell density culture system and that IgG is not a necessary cell surface isotype for precursors of IgG-secreting cells.
Human T Cell Differentiation Antigens and Correlation of Their Expression with Various Markers of T Cell Maturation
Authors: Boumsell Laurence , Bernard Alain , Coppin Hélène , Richard Yolande , Penit Claude , Rouget Pierre , Lemerle Jean , Dausset Jean 
Published: December 2022

Abstract
Two sets of differentiation antigens are demonstrated on human T cells by using 11 heterologous anti-human antisera raised against various normal and malignant T cells. The two antigenic determinants from the first set of differentiation antigens are expressed only on thymus cells and on T lymphoblasts, whereas the two antigenic determinants from the second set are expressed on blood T cells, Sezary cells, T.CLL cells, and thymus cells. Four T cells phenotypes are thus defined; two phenotypes are expressed only by T lymphoblasts, whereas the other two phenotypes are expressed both by normal and malignant T cells. Moreover, a clear-cut relationship exists between the four T cell antigenic phenotypes and two other markers of T cell differentiation: terminal deoxynucleotidyl transferase and peanut agglutinin. Two phenotypes are linked with the presence of TdT, one phenotype is linked with the affinity for PNA, and the fourth phenotype is correlated with the absence of both markers.
Increased Prostaglandin Synthesis by Macrophages from Tumor-Bearing Mice
Authors: Pelus Louis M. , Bockman Richard S. 
Published: December 2022

Abstract
Prostaglandin E2 (PGE2) synthesis by macrophages was measured in normal and tumor-bearing mice. Splenic macrophages from C57BL mice bearing a transplantable, nonmetastasizing methylcholanthrene-induced fibrosarcoma produced significantly more PGE than cells from normal nontumor-bearing littermates. Augmented PG synthesis was found basally and after nonspecific stimulation of macrophages with endotoxin (LPS) and concanavalin A (Con A) as measured by radioimmunoassay. Resident peritoneal macrophages showed similar differences in radioimmunoassayable PGE levels. The conversion to prostaglandins of radiolabeled arachidonic acid previously incorporated into membrane phospholipids was followed over time. Macrophages from both normal and tumor-bearing animals incorporated equivalent amounts of tritiated arachidonic acid, showed similar distribution of label in phospholipid pools, and released equivalent amounts of labeled Arachidonic Acid and phospholipid. However, at both 3 and 18 hr of incubation, unstimulated macrophages from tumor-bearing animals released significantly more PGE2 and 6-keto PGF1α (the metabolite of prostacyclin) compared to macrophages from normal animals. Nonspecific stimuli (Con A and zymosan) greatly augmented PG production in both animal groups, with tumor-bearers greater than with normals. LPS caused little augmentation in basal PG secretion at 3 hr, but it greatly increased synthesis measured 18 hr later. In similar experiments, Moloney sarcoma virus (MSV) could be shown to augment PG synthesis in BALB/c mice bearing a transplantable MSV-transformed tumor line, but not in normal animals. No significant difference was noted in adherence, morphology, phagocytosis, or enzymatic activity when the resident macrophages from normal and tumor-bearing animals were compared, suggesting that they were at the same relative state of activation but differed in their capacity to synthesize prostaglandins.