bluuebunny/crossref_metadata_2025_split huggingface dataset:
A 49,000-dalton polypeptide bearing all antigenic determinants and full immunogenicity of 22-nm hepatitis B surface antigen particles.
Authors: Mishiro S , Imai M , Takahashi K , Machida A , Gotanda T , Miyakawa Y , Mayumi M 
Published: December 2022

Abstract
Spherical 22-nm hepatitis B surface antigen (HBsAg) particles with a subtype adr were purified from plasma of asymptomatic carriers of hepatitis B virus. When purified HBsAg preparation was treated with sodium dodecylsulfate in the absence of reducing agents, it yielded spherical particles with a diameter smaller than 22 nm, and in addition, a polypeptide with a molecular size of 49,000 daltons, which seemed to constitute the outer coat of HBsAg particles. The recovery of the polypeptide on the basis of optical density at 280 nm was 2%, starting from 22-nm HBsAg particles. The 49,000-dalton polypeptide apparently represented a structural unit of the surface of HBsAg particles, since it bore all common (a, Re) and subtypic (d, r) determinants with essentially the same antigenic titers as intact HBsAg particles. Furthermore, this polypeptide was equally immunogenic as 22-nm HBsAg particles in raising corresponding antibodies in mice. When the 49,000-dalton polypeptide was reduced in the presence of 2-mercaptoethanol, it cleaved into 22,000- and 27,000-dalton polypeptides with a drastic decrease in both antigenicity and immunogenicity. These results indicate the different molecular arrangements between outer coat and inner portion of HBsAg particles, and a potential application of the 49,000-dalton polypeptide as a component vaccine, owing to its strong antigenicity both in vitro and in vivo.
Murine cell surface immunoglobulin: two native IgD structures.
Authors: Pollock R R , Mescher M F 
Published: December 2022

Abstract
Murine spleen cell surface IgD is found in two forms upon SDS-polyacrylamide gel electrophoresis under nonreducing conditions. Both IgDI and IgDII are present on the surface of intact cells and appear to be native structures. Neither form could be accounted for by proteolytic degradation or disulfide bond rearrangement. IgDII has an apparent m.w. of 96,000, suggesting an HL structure. IgDI has an apparent m.w. of 150,000, approximately 33,000 daltons lower than that expected for an H2L2 structure. Significant variation in the relative amounts of IgDI and IgDII was found when mice of different strains were examined.
Differential natural killer cell reactivity against T cell lymphomas by cells from normal or stimulated mice.
Authors: Tai A , Burton R C , Warner N L 
Published: December 2022

Abstract
One of the major problems confronting the study of NK cell populations concerns their potential recognition patterns and specificity. In this study three T cell lymphomas that differ markedly in their susceptibility to NK-mediated lysis from normal mice are shown to bear quantitatively but not qualitatively different degrees of NK target structures. The ability of these tumors to be lysed by NK cells can be drastically changed by augmentation of NK activity by LCM virus, but in a manner that differs relatively for the different targets. Comparison of the growth of these tumors in vivo strongly suggests an in vivo action for NK cells.
Cellular requirements for antigen presentation in the induction of a thymus-independent antibody response in vitro.
Authors: Kirkland T N , Sieckmann D G , Longo D L , Mosier D E 
Published: December 2022

Abstract
The ability of various cell populations to bind and present the thymus-independent antigen TNP-Ficoll to a responding cell population was assessed. The in vitro antibody response to TNP-Ficoll depends upon the presence of B lymphocytes and plastic-adherent accessory cells, but does not require T lymphocytes. Purified B cells were the most effective population in binding and presenting TNP-Ficoll, and adherent cells did not perform this function. Antigen binding and presentation was antigen specific and could be blocked with anti-mu antibody, but not by antibodies directed against other immunoglobulin classes. Spleen cells from mice genetically unresponsive to TNP-Ficoll (CBA/N X BALB/c F1 males) were equally effective as normal spleen cells in antigen binding and presentation. We conclude that the initial events in the induction of the antibody response involves antigen binding by B cells, and that subsequent activation of the subset of B cells that can respond to TNP-Ficoll proceeds either via B cell-B cell interaction or B cell-dependent transfer of antigen to macrophage-like cells.
Structural studies on the murine fourth component of complement (C4). IV. Demonstration that C4 and Slp are encoded by separate loci.
Authors: Carroll M C , Passmore H C , Capra J D 
Published: December 2022

Abstract
The S region of the murine major histocompatibility complex (MHC) encodes the structural gene for the fourth complement component (C4) and controls C4 serum levels and expression of the sex-limited protein (Slp). Although Slp was first throught to be an allele of C4, more recent studies have suggested that Slp is either a modified product of the C4 locus or is encoded at a separate locus. By using a sensitive peptide analysis technique, each of the three constitutive polypeptide chains of C4 and Slp was compared, and multiple distinct peptides as well as several shared peptides were detected. These results demonstrate that although C4 and Slp undoubtedly share a common genetic origin, they are encoded by separate structural genes.
Ontogeny of T cell function. I. Acquisition of helper cell activity by the thymus.
Authors: Haines K A , Siskind G W 
Published: December 2022

Abstract
The ontogeny of the ability of thymus cells to "help" the response to a T-dependent antigen was studied in a cell transfer system. Lethally irradiated, thymectomized mice were reconstituted with thymus cells from donors of various ages together with rabbit anti-mouse brain antiserum and complement- (C) treated bone marrow cells. Mice were immunized with TNP-BGG and the magnitude and affinity distributions of their splenic plaque-forming cell (PFC) responses were assayed 3 weeks later. The results indicate that neonatal thymic cells are capable of helping a direct PFC response but cannot mediate the shift to indirect plaque formation. The ability to mediate the switch to an indirect PFC response is a separate maturation event that occurs between birth and 2 to 4 days of age. The thymus cell population from 2-day-old donors is already capable of mediating selection of high affinity PFC. Neonatal cells residing in an irradiated, thymectomized or nonthymectomized adult recipient for 7 days, even in the presence of adult rabbit anti-mouse brain and C-treated syngeneic spleen cells, did not mature to be capable of mediating an indirect PFC response.
T cell requirements for generation of helper factor(s) in man: analysis of the subsets involved.
Authors: Reinherz E L , Kung P C , Breard J M , Goldstein G , Schlossman S F 
Published: December 2022

Abstract
Lymphocyte mitogenic factor functions as a nonspecific helper molecule generated from antigen stimulation of T lymphocytes. As such, it induces proliferation of all major lymphocyte subclasses (T, B, and Null cells) and B cell immunoglobulin synthesis. In the present study, the specific T cell subset requirements for LMF production were determined in man. By utilizing the OKT4 monoclonal antibody directed at the human inducer T cell subset, T lymphocytes were separated into OKT4+ and OKT4- subpopulations. The antigen stimulated OKT4+ subset generated LMF in a fashion comparable to the unfractionated T cell population and was itself capable of directly inducing B cell proliferation and antibody production. In contrast, LMF could not be generated from the OKT4-T cell subset although this population accounted for 40% of the unfractionated T cell population. In addition, the OKT4- subset was unable to facilitate B cell differentiation in the presence of soluble antigen. These studies provide the first report of T cell subset restriction for generation of helper factors in man and further stress the importance of the OKT4+ inducer population in regulation of the human immune response.
Expression of both I-A and I-E/C subregion antigens on accessory cells required for in vitro generation of cytotoxic T lymphocytes against alloantigens or TNBS-modified syngeneic cells.
Authors: Pettinelli C B , Ahmann G B , Shearer G M 
Published: December 2022

Abstract
We have previously reported that radioresistant, Thy 1-negative accessory cells (SAC) are required for the in vitro generation of cytotoxic T-effector cells to allogeneic or trinitrophenyl-modified syngeneic cells. These SAC were found to provide accessory functions irrespective of whether they were syngeneic, semi-syngeneic, or allogeneic to the responding cells. To further characterize the accessory cells active in CML, the expression of Ia antigens on this functional population was assessed by pretreated SAC with anti-Ia reagents and complement and by testing the accessory cell function of these treated populations. The results of these studies demonstrated that the relevant accessory cells for allogeneic and TNP-self CTL express Ia determinants encoded by genes mapping in the I-A and I-E/C subregions. For the TNP-self CTL the accessory function of both SAC syngeneic or allogeneic to the responding and stimulating cells was specifically abrogated by treatment with anti-Ia reagents and complement.
A monoclonal antibody reactive with human peripheral blood monocytes.
Authors: Breard J , Reinherz E L , Kung P C , Goldstein G , Schlossman S F 
Published: December 2022

Abstract
A monoclonal antibody directed at a determinant on human peripheral blood monocytes was produced and characterized. This hybridoma antibody, termed OKM1, was reactive by indirect immunofluorescence and complement- (C) mediated lysis with adherent mononuclear cells. OKM1 was unreactive with lymphocytes, thymocytes, lymphoblastoid cell lines, and tumor cells of the T or B cell lineage. In contrast, acute myelomonocytic leukemia cells and granulocytes were reactive with the antibody. Pretreatment of peripheral blood mononuclear cells with OKM1 and C before culture with soluble antigens totally abolished their antigen-induced proliferative response. This function was restored by addition of 1% adherent cells. These findings provided additional support for the notion that OKM1 was reactive with monocytes. In addition, OKM1 appeared to define two distinct populations of monocytes; an adherent population of large cells bearing surface Ia determinants and a nonadherent population of small, Ia-negative cells. These OKM1+ Ia- cells were found to be a contaminant of most fractionated mononuclear cell subsets including the E-SIg-Null cell population.
Diffusion control of the binding of carcinoembryonic antigen (CEA) with insoluble anti-CEA antibody.
Authors: Frackelton A R , Weltman J K 
Published: December 2022

Abstract
Analysis of the kinetics of CEA binding to rabbit anti-CEA antibody insolubilized on filter paper discs provided six lines of evidence indicating diffusion control of this reaction: 1) The observed forward rate constant, k1obs, decreased when solvent viscosity was increased with sucrose or Ficoll. 2) k1obs per receptor site increased from 1.2 x 10(4) M-1 sec-1 to 2.6 x 10(4) M-1 sec-1 as receptor site density on immunosorbent discs decreased from 5.2 x 10(-13) to 2.1 x 10(-13) moles/disc. 3) Stirring the reacting mixture of CEA and insoluble anti-CEA increased k1obs from 1.2 x 10(4) M-1 sec-1 to 3.4 x 10(4) M-1 sec-1. 4) The activation energy for CEA-insoluble anti-CEA binding was indistinguishable (p greater than 0.1 by t-test) from 4.1 Kcal/mole expected for diffusion controlled reactions. 5) Bimolecular reaction theory predicted a diffusion limited forward rate constant, k1max, for CEA binding to insoluble anti-CEA, which was consistent with our observed k1 of 1.2 x 10(4) M-1 sec-1. 6) k1obs for CEA binding to soluble rabbit anti-CEA antibody was 6.4 x 10(4) M-1 sec-1, 5 times faster than the k1obs of the heterogeneous phase reaction for receptor site density of 5.2 x 10(-13) moles/disc. Diffusion control of ligand binding to insoluble receptors, as exemplified by the CEA-insoluble anti-CEA model system, may be a very general biologic phenomenon.
The formation and release of slow reacting substance of anaphylaxis (SRS-A) by rat and mouse peritoneal mononuclear cells induced by ionophore A23187.
Authors: Orange R P , Moore E G , Gelfand E W 
Published: December 2022

Abstract
The capacity of the calcium ionophore A 23187 to induce the formation of SRS-A was used in an attempt to identify the nature of the cells that are responsible for the formation of this material. In agreement with previous observations, rat and mouse peritoneal mast cells were found to contribute very little to the total amount of SRS-A that was made, and in fact their removal from the cell suspensions resulted in an augmentation of the amount of SRS-A that was found. Discontinuous Ficoll and bovine serum albumin gradients were employed to further characterize these SRS-A-releasing cells from induced peritoneal cells. SRS-A was produced by nonspecific esterase-positive and latex-phagocytizing mononuclear cells. By electron microscopy, these cells had macrophage-like characteristics. In contrast, rat alveolar macrophages and a macrophage-like cell line of mouse origin both failed to produce large amounts of SRS-A. The results suggest that SRS-A formation may be the property of an as yet imperfectly characterized subclass of macrophages.
Mechanisms of lymphocyte activation: linkage between early protein synthesis and late lymphocyte proliferation.
Authors: Varesio L , Holden H T 
Published: December 2022

Abstract
An experimental model has been developed to study the mechanisms of lymphocyte activation. Using this model we examined the relationship between early protein synthetic events and the late proliferative response to Con A. We found that transient puromycin or cycloheximide-induced inhibition of protein synthesis during the first hour of stimulation by Con A resulted in either inhibition or enhancement of the response, depending on the subsequent treatment of the cells. If the lymphocytes were either not restimulated or restimulated immediately after the initial pulse with metabolic inhibitor plus Con A, there was a decrease in the proliferative response. However, if the cells were restimulated with Con A 24 hr later, there was a shift in the kinetics resulting in a prolonged and increased response. Inhibition of protein synthesis at 6 hr after stimulation with Con A produced no noticeable effects. Hence, there are protein synthetic events that take place during the first hours of stimulation that are critical for the development of the proliferative response. The possibility that these early protein synthetic events are the target for macrophage-mediated regulation of lymphocyte function is discussed.
Identification of a unique idiotype in cerebrospinal fluid and serum of a patient with multiple sclerosis.
Authors: Baird L G , Tachovsky T G , Sandberg-Wollheim M , Koprowski H , Nisonoff A 
Published: December 2022

Abstract
Anti-idiotypic antibodies were prepared in mouse ascites fluid against the CSF-IgG of a patient with multiple sclerosis. After adsorption with pooled human IgG, the ascites fluid antibodies precipitated 20% of labeled autologous CSF IgG. By using a competitive radioimmunoassay, less than one microgram of unlabeled CSF IgG produced 50% inhibition of binding autologous 125I-labeled CSF IgG, whereas 50 micrograms of normal HIgG was not inhibitory. The idiotype could be found in both serum and CSF IgG and persisted over a 5-year period. The absolute concentration of idiotype in the CSF varied somewhat but remained from 4 to 10 times greater than that of the serum. One of 14 heterologous MS CSF was found to contain small amounts of inhibitory protein; eight CSF from patients with other neurologic diseases did not contain the idiotype.
Effects of adriamycin on the activity of mouse natural killer cells.
Authors: Santoni A , Riccardi C , Sorci V , Herberman R B 
Published: December 2022

Abstract
Adriamycin, a widely employed anti-neoplastic agent, was found to have either inhibitory or stimulatory effects on NK activity, depending on the site examined. A single i.p. administration of ADM resulted in a rapid increase of cytolytic activity by PEC of various mouse strains. The effector cells appeared to be NK cells, being nonadherent and nonphagocytic; they expressed low amounts of Thy 1.2 antigen and had the same pattern of specificity as splenic NK cells. In contrast to the stimulatory effects of NK activity of PEC, ADM caused a transient dose-dependent depression of NK activity in the spleen, with a peak reduction at day 3 and recovery within a few days thereafter. The depressed NK activity could be reversed by removal of adherent cells by passage through a nylon column. Moreover, ADM induced cytostatic activity against tumor cells by macrophages, suggesting that activated macrophages may be responsible for suppression of splenic NK activity. The possible modulation of the levels of NK activity by ADM-induced macrophages was supported by mixture experiments, in which plastic adherent spleen cells from ADM-treated mice, but not from normal mice, inhibited the NK activity of normal spleen cells.
Specific spontaneous cytotoxic activity in human T cell colonies.
Authors: Price G B , Teh H S , Miller R G 
Published: December 2022

Abstract
Cells in T cell colonies grown in vitro from normal human peripheral blood leukocytes can kill a variety of different target cells against which the blood donor has not knowingly been previously sensitized, i.e., the colony cells exhibit spontaneous cytotoxicity. Tumor target cells are preferentially killed. The ability to kill two different targets segregates independently in different colonies, which implies that the effector cells are specificity restricted. A majority (perhaps all) of the effector cells possess receptors for sheep erythrocytes and do not possess receptors for the Fc end of IgG, making it unlikely that they are either "natural killer" (NK) cells of cells mediating antibody-dependent cellular cytotoxicity. They may, however, be cytotoxic T lymphocytes.
Anti-self receptors. II. Demonstration of H-2L region-restricted receptors on subpopulations of peripheral T and B lymphocytes.
Authors: Sia D Y , Parish C R 
Published: December 2022

Abstract
Subpopulations of murine spleen, lymph node, and bone marrow cells can bind autologous erythrocytes. The specificity of this interaction was investigated and it was found that these lymphoid cells, like thymocytes, primarily recognize self-H-2L antigens on red cells. Three experimental approaches were used to reach this conclusion: i) The inhibition of autorosetting with erythrocyte sonicates from different H-2 congenic and recombinant mouse strains; ii) the specific blocking of autorosette-inhibition with anti-H-2L antibodies, and iii) the analysis of H-2L mutant mice. The inhibition studies also demonstrated that extrathymic lymphocytes, like thymocytes, carry receptors that can distinguish between b, q and s haplotypes but cannot differentiate between the H-2L molecules expressed by d and k haplotypes. It was found that subpopulations of both T and B lymphocytes autorosette via H-2L restricted receptors. In fact, the majority (80%) of autorosetting cells in spleen were B lymphocytes. Furthermore, the H-2L restricted receptors on B lymphocytes were distinct from surface Ig and could develop in athymic (nude) mice. These findings imply that H-2 restricted receptors on lymphocytes play a much more fundamental and comples role in the immune system than simply directing the interaction of cytotoxic T lymphocytes with target cells.
H-2K/H-2D and Mls and I region-associated antigens stimulate helper factor(s) involved in the generation of cytotoxic T lymphocytes.
Authors: Scott J W , Ponzio N M , Orosz C G , Finke J H 
Published: December 2022

Abstract
This study examines the antigen that stimulate production or release of a soluble helper factor(s) involved in development of cytotoxic T lymphocytes (CTL). Antigens associated with the Mls locus, I and K/D regions of the MHC were all capable of stimulating responder cells in MLC to produce helper factor. These supernatant fluids were all capable of providing "help" for the generation of cytotoxic T lymphocytes in MLC in which spleen cells are stimulated by allogeneic heat-treated thymocytes or splenocytes. Previous reports from our laboratory as well as others have shown that heat-treated cells do not stimulate a cytotoxic response. Heat-treatment of Mls, I, and H-2K/H-2D region incompatible stimulatory cells in MLC eliminated their ability to induce responder cells to produce helper factor, suggesting this is the mechanism whereby heat-treatment reduces the ability of cells to stimulate cell-mediated lympholysis (CML). The inability of supernatant fluids, from MLCs in which heat-treated cells were the stimulators, to assist in the generation of cytotoxic T cells did not appear to be the result of any suppressive factor induced by such treatment. Further, the antigens that stimulate pre-killer cells appear functionally distinct from those heat labile antigens (Mls, I, H-2K/H-2D associated) that stimulate helper factor production since heat-treated allogeneic cells served as stimulators of cytotoxicity provided helper activity was added to the MLC.
Isolation and purification of a type-specific antigen from Chlamydia trachomatis propagated in cell culture utilizing molecular shift chromatography.
Authors: Hourihan J T , Rota T R , MacDonald A B 
Published: December 2022

Abstract
Various techniques have been utilized for antigen solubilization, isolation, and purification. This report is the first to describe the isolation and purification of a type-specific antigen from Chlamydia trachomatis serotype A grown in cell culture. The type-specific antigen was prepared from Chlamydia trachomatis serotype A organisms grown in baby hamster kidney cells (BHK21). The extraction process employed a combination of both pH change and Triton X-100 solubilization. The soluble extract was radioiodinated and subjected to ion exchange and gel filtration chromatography. The fractions eluted were tested for type specificity utilizing the IgG prepared from exhaustively cross-absorbed hyperimmune sera from rabbits immunized with homologous organisms. Molecular shift chromatography was employed for analysis. Small samples of the isolated antigen were later used as markers for preparation of larger quantities necessary for antigenic characterization. The purified type-specific antigen has a m.w. of 30,000 to 32,000.
Mediation of macrophage collagenase production by 3'-5' cyclic adenosine monophosphate.
Authors: McCarthy J B , Wahl S M , Rees J C , Olsen C E , Sandberg L , Wahl L M 
Published: December 2022

Abstract
The production of collagenase by lipopolysaccharide-(LPS) activated guinea pig macrophages is mediated by prostaglandins (PG) of the E series. After stimulation of guinea pig macrophages with LPS, extracellular PGE levels and cellular cAMP levels are elevated. Indomethacin inhibits not only PG synthesis, but also cAMP and collagenase production in LPS-stimulated macrophage cultures. In these indomethacin-inhibited cultures containing LPS, dibutyryl (dB) cAMP, or cholera toxin can restore macrophage collagenase production but not PG synthesis. Moreover, dBcAMP and cholera toxin enhance collagenase production in LPS-activated cultures. Initial activation of the macrophages by an agent such as LPS is a prerequisite for synthesis of collagenase, since in the absence of LPS, dBcAMP or cholera toxin alone are ineffective stimuli. These findings clearly demonstrate a role for PG-induced elevations of cAMP in the production of collagenase by LPS-activated macrophages.