bluuebunny/crossref_metadata_2025 huggingface dataset:
Regulation of the in Vitro Early Anamnestic Antibody Response by Exogenous Cholera Enterotoxin and Cyclic AMP
Authors: Cook Richard G. , Stavitsky Abram B. , Schoenberg Melvin D.
Published: December 2022

Keyhole limpet hemocyanin was injected into the hind foot pads of rabbits. Six days later cell suspensions were prepared from the popliteal lymph nodes. Various amounts of hemocyanin (1 ng to 100 µg) were added to 1 × 107 cells to induce an anamnestic antibody response. Various amounts of cholera enterotoxin, which stimulates the enzyme adenylate cyclase, or dibutyryl cyclic adenosine 3′5′-monophosphate (AMP), were added to the cultures with or without hemocyanin. De novo synthesis of antibody, protein, deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) from radioactive precursors was assayed. The addition of cholera toxin or dibutyryl cyclic AMP for the first 24 hr with optimal (1 µg) or supraoptimal (100 µg) amounts of hemocyanin enhanced antibody synthesis by at least 100 to 200%. Addition of the toxin or dibutyryl cyclic AMP for the same period to cells minus hemocyanin or with suboptimal amounts (1 to 100 ng) of antigen failed to enhance antibody synthesis. Addition of these agents for 72 to 120 hr to hemocyanin-induced cultures consistently inhibited antibody synthesis. These agents slightly inhibited DNA and RNA synthesis. The increase in protein synthesis caused by the toxin or dibutyryl cyclic AMP was almost totally accounted for by the increase in antibody synthesis. Neither toxin nor cyclic nucleotide promoted the antibody response in the presence of antibody to rabbit thymus-derived lymphocytes; these lymphocytes as well as bursa-equivalent lymphocytes were required for potentiation of the response. Macrophages were not required either for induction of the anamnestic response or for enhancement of this synthesis by cyclic nucleotide or cholera toxin. Both IgM and IgG antibody synthesis were regulated by exogenous cholera toxin and dibutyryl cyclic AMP. A number of possible cellular mechanisms of regulation of the antibody response through the cyclic AMP pathway were discussed. These included the effects of modifications of this pathway on the activities of T lymphocytes early (0 to 24 hr) and B lymphocytes late (72 to 120 hr) in the response and on the apparent reversal of high zone tolerance.
Cytotoxic Effects of Antigen- and Mitogen-Induced T Cells on Various Targets
Authors: Bevan Michael J. , Cohn Melvin
Published: December 2022

Mitogen-induced cytotoxicity was studied by culturing mouse spleen cells with an optimum mitogenic dose of concanavalin A (Con A) for 2 days and, after washing, assessing their ability to lyse tumor targets. We show that rapid lysis occurs only when the correct concentration of an agglutinating mitogen (phytohemagglutinin P (PHA) or Con A) is present in the assay. PHA is more efficient than Con A in revealing the cytotoxic effect. The Con A-induced effector cytotoxic cell is shown to be sensitive to anti-ϑ serum and complement. Cytotoxic T cells were also induced by H-2 different allo-immunization. These effector cells specifically lyse targets which bear the immunizing H-2 antigens in the absence of PHA. When PHA is present in the assay, they will also lyse syngeneic tumor targets nonspecifically. Since not all dividing T cells (e.g., T lymphomas, and T blasts induced by M locus different, H-2 similar mixed lymphocyte culture) lyse PHA-P815, we propose that this assay measures only a subset of effector T cells, namely, cytotoxic T cells, regardless of their antigen specificity.

The tumor cells, P815 and EL4, are sensitive both to antigen-specific T cell-mediated lysis in the absence of PHA and to nonspecific, PHA-revealed lysis. Small lymphocytes, T cell blasts, and B cell blasts are sensitive to lysis by T cells which are directed against H-2 antigens on their surface, but are not very susceptible to nonspecific T cell lysis in the presence of PHA. The reason for this difference in susceptibility of tumor and normal cells to PHA-revealed nonspecific T cell lysis is not known but may have some relevance to in vivo tumor rejection.
Macrophage Requirement for Production of Guinea Pig Migration Inhibitory Factor (MIF) in Vitro
Authors: Nelson Robert D. , Leu Richard W.
Published: December 2022

Methods devised for generation and assay of migration inhibitory factor (MIF) on a reduced scale have permitted the performance of experiments which demonstrate that glass bead column-purified guinea pig lymph node lymphocytes do not produce MIF or proliferate in response to antigen. Evidence that the macrophage is the essential cellular element eliminated by the purification procedure is demonstrated by the restoration of both lymphocyte responses upon addition of 5% macrophages to the purified lymphocytes. Autologous, immune and syngeneic, non-immune peritoneal exudate macrophages were equally effective in restoring MIF production by purified lymphocytes. Supernatants which inhibited the migration of peritoneal exudate macrophages had only minimal or no effect on the migration of alveolar macrophages, confirming that the inhibitory effects studied were attributable to MIF and not cytophilic antibody.
Synthesis of Antibody and Immunoglobulins without Detectable Antibody Function in Cells Responding to Horseradish Peroxidase
Authors: Miller Hugh R. P. , Ternynck Thérèse , Avrameas Stratis
Published: December 2022

The kinetics of immunoglobulin-synthesizing cells (IFC) and antibody-forming cells (AFC) are compared in the popliteal nodes of mice challenged, in the hind footpads, with horseradish peroxidase (PO) in Freund's complete adjuvant. A rise in the number of IFC without antibody function precedes the appearance of AFC. IFC reach peak numbers 7 days before AFC. Control experiments show that the majority of IFC without antibody function are responding to PO and not to adjuvant. Kinetic and radioautographic data suggest that IFC arise by division and differentiation; however, the doubling time of AFC is too rapid to be accounted for by cell division alone. Double staining techniques revealed the presence of immunoglobulin and antibody in different compartments of the same cell in 5 to 15% of the AFC. It is postulated that some AFC are recruited, possibly from cells already synthesizing immunoglobulin determinants.
Distribution and Association of Heavy and Light Chain Variable Region Subgroups among Human IgA Immunoglobulins
Authors: Capra J. Donald , Kehoe J. Michael
Published: December 2022

A series of randomly selected human IgA myeloma proteins were examined for the presence of the VHIII subgroup, as defined by the possession of an unblocked amino terminal amino acid and characteristic linked residues along the heavy chain. Blocked heavy chains were classified as VHB proteins. The data showed that 20 of 30 such random alpha chains (67%) were classifiable as members of the VHIII subgroup. Similarly, 75% of heavy chains isolated from pools of normal serum IgA contained a VHIII variable region. The pattern stands in marked contrast to the situation in human IgG proteins where approximately 20% of heavy chains from both pools and myeloma proteins are VHIII. There was thus a clear divergence of the pattern of variable region: constant region association between these two classes of immunoglobulin.

Some more limited data were obtainable for the light chains of the IgA myeloma proteins. Certain predilections for light chain subgroup:heavy chain subgroup (VHIII or VHB) associations were discernable, but more data are required for definite conclusions.

Overall, this study suggests that although the pool of available variable region sequences is indeed shared among human IgA and IgG proteins, the partitioning is not exactly equivalent between the two immunoglobulin classes. The pattern is particularly apparent at present for the VHIII subgroup which comprises approximately 70% of human alpha chains and only about 20% of human gamma chains.
Suppression of Reaginic Antibody Formation
Authors: Lee Weng Y. , Sehon Alec H.
Published: December 2022

Reaginic antibodies to DNP and ovalbumin were induced readily in B6D2F1 mice by a single intraperitoneal injection of 1 µg of DNP-ovalbumin suspended with 1 mg aluminum hydroxide in 0.5 ml of saline. The formation of anti-DNP reaginic antibody was completely suppressed by treatment of mice with a conjugate consisting of the hapten coupled to an isologous, nonimmunogenic carrier, viz., murine γ-globulins. However, this treatment did not affect the level of antibody formation to the carrier of the immunizing antigen. The induction of unresponsiveness was dose dependent, complete suppression being achieved with 1 mg of the tolerogen. The state of unresponsiveness could be maintained for prolonged periods (these observations were made over a period of at least 8 months) by repeated injections of the tolerogen at intervals of 2 months. More importantly, the state of unresponsiveness could be induced readily not only in normal, but also in sensitized mice, i.e., this treatment was capable of abrogating an ongoing reaginic response, and the suppression was immunologically specific. Hence this system appears to have a great potential for adaptation to the treatment of allergic diseases in man.
Ly-4.2: A Cell Membrane Alloantigen of Murine B Lymphocytes
Authors: McKenzie Ian F. C. , Snell George D.
Published: December 2022

The Ly-4 locus defines an alloantigenic specificity present on the surface of lymphocytes of some mouse strains and detected in lymphocytotoxicity tests by an antiserum (BALB/c × SWR)F1 anti-B10.D2. In this paper are presented results which indicate that Ly-4.2 is predominantly represented on B cells and not T cells. In cytotoxicity tests with rabbit complement, the distribution of Ly-4.2 is restricted: thymus 5%, TDL 12%, spleen 60%, lymph node 30%, bone marrow 36%, Peyer's patches 55%, peritoneal exudate cells 35%, and peripheral lymphocytes 35%. This distribution is the reciprocal of that obtained with anti-Thy-1 antiserum. Further, when both reagents were used together, almost all cells in these tissues were lysed, excepting those with bone marrow. When anti-Ly-4.2 and anti-Thy-1.2 were used sequentially, it was apparent that these specificities were present on different cell populations. As Thy-1 is a marker for T cells, Ly-4 is therefore, presumably, a marker for B cells. This conclusion was confirmed by testing mice depleted of T cells (“nude”; thymectomy + anti-lymphocyte serum treatment; thymectomy, irradiation + reconstitution with bone marrow) where the majority of lymphocytes were Ly-4.2+, Thy-1.2-; and by testing tumors, where, for the most part, this reciprocal relationship held true. Appropriate studies indicate that the Ly-4.2 antibody does not detect a surface immunoglobulin allotype. Anti-Ly-4.2 antiserum may provide a useful alloantigenic marker distinct from immunoglobulin, mouse-specific bone marrow-derived lymphocyte antigen, and “β” for detecting some or all, B cells.
Ly-4.2: A Cell Membrane Alloantigen of Murine B Lymphocytes
Authors: McKenzie Ian F. C.
Published: December 2022

The alloantigenic specificity Ly-4.2 can be detected on a proportion of lymphocytes by the antiserum (BALB/c × SWR)F1 anti-B10.D2. In the preceding study it was shown that these lymphocytes were not thymus-derived (T) cells, as they were Thy-1 (ϑ)(-), and were therefore presumably B (bone marrow-derived) cells. Evidence is now presented for the reaction of the Ly-4.2 antiserum with functional B cells. Thus, the Ly-4.2 and Thy-1.2 specificities were detected on antigen-binding rosette-forming cells (RFC) in mice both immune and non-immune to sheep red cells (SRC). RFC formed to endotoxin lipopolysaccharide (LPS) were also Ly-4.2(+). Memory cells to both SRC and LPS could be detected with anti-Ly-4.2 and anti-Thy-1.2 antisera, thereby indicating that both T and B cells are involved in memory to these antigens. Both direct and indirect antibody-forming cells (the PFC) could be inhibited, in vitro, by anti-Ly-4.2 antiserum, although it is likely that not all PFC are Ly-4.2(+).

Neither of the specificities Ly-4.2 nor Thy-1.2 were detected on the bone marrow precursor of the splenic colony forming unit (the CFU). In an assay for B cells, the treatment of lymph node or spleen cells with anti-Ly-4.2 before transfer to irradiated recipients could inhibit the ability of these cells to make PFC to SRC, and this capacity could only be restored by bone marrow cells and not by thymus cells. These studies provide clear evidence for the presence of the Ly-4.2 specificity on antibody-forming cells and their precursors (B cells).
Rabbit Lymphocyte Populations Responding to Haptenic and Carrier Determinants for DNA Synthesis
Authors: Delespesse Guy , Ishizaka Kimishige , Kishimoto Tadamitsu
Published: December 2022

Mesenteric lymph node cells from rabbits primed with dinitrophenyl derivative of either Ascaris extract (DNP-Asc) or ragweed fraction D (DNP-Rag) were stimulated by the priming antigen, free homologous carrier, or with the hapten conjugated with rabbit serum albumin (DNP-RSA), and increase in DNA synthesis was observed by 3H-thymidine incorporation. The results showed that both free carrier and DNP-RSA stimulated DNA synthesis. The response of the primed lymph node cells to DNP-homologous conjugate was slightly higher than that to free carrier, but the optimal concentration of both antigens for maximal thymidine incorporation was 10 to 100 µg/ml. This concentration was about 100 times higher than the optimal concentration of the same antigens for maximal antibody response in vitro. The DNA synthetic response to DNP-RSA was much less than that obtained by free carrier, and the optimal concentration of DNP-RSA for the response was comparable to the concentration of DNP-homologous carrier conjugate to induce maximal anti-DNP antibody response. The relative importance of immunoglobulin bearing (B) cells and T cells in the DNA synthetic responses was assessed by fractionating lymph node cells with antigen-coated or antiimmunoglobulin coated cellular immunosorbent. The results indicated that hapten-specific, immunoglobulin-bearing cells (B cells) are responsible for the DNA-synthetic response to DNP-RSA, whereas B cells play a minimal role in the response to free carrier.
Induction of Lymphocyte Cytotoxicity by Modification of the Effector or Target Cells with Periodate or with Neuraminidase and Galactose Oxidase
Authors: Novogrodsky Abraham
Published: December 2022

Treatment of mouse spleen cells with periodate (NaIO4) or with neuraminidase and galactose oxidase (NAGO) induces blastogenesis and renders the cells cytotoxic to mastocytoma (P815) target cells. Treatment of target cells (P815 cells and turkey erythrocytes) with NaIO4 or with NAGO renders them susceptible to cytolysis by untreated mouse spleen cells. The cytotoxicity induced by NaIO4 is reduced upon reacting the NaIO4-treated, effector or target cells with borohydride or hydroxylamine. Thus the formation of free surface aldehydes on either the effector or target cell induced a cytotoxic effect. It is postulated that cross-linkage via a Schiff base between effector and target cell initiates the cytotoxic effect. Cytotoxicity induced by NaIO4 or NAGO is immunologically nonspecific and is independent of major antigenic differences between effector and target cells. Phagocytic cells are not involved in NaIO4-or NAGO-induced cytotoxicity toward P815 target cells.
Biological Expressions of Lymphocyte Activation
Authors: Rich Robert R. , Rich Susan Solliday
Published: December 2022

Thymus-derived lymphocytes (T cells) from mouse spleen, activated in vitro or in vivo with concanavalin A (Con A), suppress proliferative responses of syngenic lymphocytes in mixed lymphocyte reactions (MLR). Replication in vitro was not required for expression of suppressor activity by Con A-activated cells and was blocked in MLR by treating suppressor cells with mitomycin C or irradiation. Kinetics of MLR responses and viability of cultures were not altered by addition of activated suppressor cells. The data are consistent with a direct inhibitory effect of suppressor T cells on antigen-induced DNA replication. These observations extend a model previously described for regulation of antibody synthesis by Con A-activated T cells to control of cell-mediated immune responses. This model should be particularly useful in further definition of regulatory T cell subpopulations, and in investigation of interactions and relationships between such populations.
The Diisopropylfluorophosphate Inhibitable Step in Antigen-Induced Histamine Release from Human Leukocytes
Authors: Pruzansky Jacob J. , Patterson Roy
Published: December 2022

DFP inhibits early events in antigen-induced histamine release from human leukocytes. If added to cells 5 min or more after antigen it is ineffective. If added with antigen it can be removed at 5 min but release will still be inhibited. In contrast, ethylenediaminetetraacetate (EDTA) and 2 deoxyglucose (2DG) still inhibit the reactions when added 5 min after antigen.

During incubation of leukocytes for 90 to 120 min at 0°C they react with specific antigen since they subsequently release significant quantities of histamine after washing and reincubation at 37°C without addition of antigen. Such priming at 0°C is at least equivalent to priming for 2 to 4 min at 37°C. During antigen priming at 0°C the cells are not activated beyond the step in the release sequence which is inhibited by diisopropylfluorophosphate (DFP). This is apparent from the undiminished inhibitory activity of DFP on these cells. Furthermore, cells primed with antigen at 0°C in the presence of DFP release as much histamine after washing and incubation at 37°C as control cells primed in the absence of DFP.

Incubation of leukocytes with specific antigen at 37°C for 3 min resulted in significant but not quite complete priming for subsequent histamine release in the absence of antigen. Most of these primed cells were not activated beyond the step inhibitable by DFP. However, some had completed the entire sequence including the release of histamine while others had not released their histamine but were not inhibited by DFP from subsequent release.

After 5 min incubation with antigen at 37°C almost all leukocytes had progressed beyond the stage which is inhibited by DFP.

Incubation of leukocytes at 37°C with DFP but without antigen for up to 15 min followed by washing did not impair subsequent antigen-induced histamine release by these cells. Thus, DFP was inhibitory under these conditions only after antigen activation of leukocytes.
The Initiation of Mast Cell Degranulation: Activation at the Cell Membrane
Authors: Morrison D. C. , Roser J. F. , Cochrane C. G. , Henson P. M.
Published: December 2022

The low molecular weight mast cell activator, polymyxin B, has been covalently bound to an insoluble matrix of Sepharose 4B. It has been demonstrated that mast cells in preparations of rat peritoneal cells bind to Sepharose 4B-polymyxin B beads but not to control beads. The bound cells are stimulated to degranulate by this interaction at the cell membrane with the resultant release of biogenic amines.
The Transfer of Tolerance to Dncb-Contact Sensitivity in Guinea Pigs by Parabiosis
Authors: Polak Ladislav
Published: December 2022

Normal guinea pigs parabiosed for 10 days with guinea pigs tolerant to DNCB-contact sensitivity became completely and permanently unresponsive when sensitized after parabiosis lasting 10 days and partially tolerant when sensitized after parabiosis lasting 2 days. On the other hand, tolerant parabionts became hypersensitive when parabiosed with normal partners which had been sensitized on the day of the operation or before the parabiosis was effected. From these results it is concluded that tolerance to DNCB-contact sensitivity in guinea pigs is a positive phenomenon affecting the afferent branch of the immune response.
Demonstration of Organ Differences in Peripheral B Cell Populations through the Use of Deficient Fetal Bovine Serum
Authors: Campbell Stephen M. , Kagnoff Martin F. , Watson James
Published: December 2022

Deficient fetal bovine serum (FBS) was used in culture to distinguish differences in the B cell populations of peripheral lymphoid organs. Culture medium supplemented with deficient FBS supported the induction of primary humoral immune responses to heterologous erythrocyte antigens in murine Peyer's patch and lymph node cultures, but not in spleen cultures obtained from the same unimmunized mice. This difference was not due to a difference in thymusderived (T) cell or adherent cell activity, or to the production of stimulating factors by Peyer's patch or lymph node cells. In view of the finding that spleen cells from mice immunized with erythrocyte antigens support immune responses in deficient FBS, we suggest that murine Peyer's patches and lymph nodes contain antigen-experienced B cells, whereas spleens contain predominately antigen-inexperienced B cells. In contrast, spleen and Peyer's patch cells cultured with deficient FBS can be induced to mediate specific cytotoxic allograft responses which are similar in magnitude to responses observed in normal FBS. Deficient FBS may provide a useful tool for distinguishing between B cells on the basis of prior antigenic encounter, and for examining the induction of T cell responses in the absence of B cell responses.
Antibody-Dependent Lymphocyte Cytotoxicity in the Murine Sarcoma Virus System: Activity of IgM and IgG with Specificity for MLV Determined Antigen (S)
Authors: Lamon Eddie W. , Skurzak Henryk M. , Andersson Birger , Whitten Hal D. , Klein Eva
Published: December 2022

Antisera with specificity for Moloney leukemia virus-(MLV) determined antigen(s) were studied for their ability to induce MLV antigen bearing target cell reduction by lymphocytes in microcytotoxicity assays.

Sera from animals which had regressed Moloney sarcoma virus (MSV) tumors as well as sera from animals with progressively growing MSV tumors were found to induce normal lymphocytes to be active against the targets. Regressor serum was found also to induce cytotoxicity by immune lymphocytes from a tumor-bearing animal 15 days after MSV and from a regressor 50 days after MSV infection.

Both the 19S and 7S Sephadex G-200 fractions of the antisera were found to induce cytotoxicity by normal lymphocytes and to potentiate the cytotoxicity of MSV immune lymphocytes. These activities were shown to be IgM and IgG, respectively, by the use of Sepharose-coupled anti-mouse IgM and anti-mouse IgG columns. All activity was removed by passing sera over both columns.
Non-T Cell-Mediated Cytolysis of Antibody-Coated Sheep Red Blood Cells Requires Mg++ but Not Ca++: An Argument against a Conventional “Stimulus-Secretion” Mechanism for Cytolysis
Authors: Golstein Pierre , Gomperts Bastien D.
Published: December 2022

“Stimulus-secretion” processes, and notably those in which the stimulus is provided by the formation of an antigen-antibody complex at the cell surface, require the presence of external Ca++. To test the possibility that effector cells, in non-T cell mediated cytolysis, might be triggered to release a cytolytic product by a similar mechanism, we investigated the requirements of this phenomenon for divalent cations. We found that Ca++ is not sufficient, not necessary, and not inhibitory, whereas Mg++ is necessary and sufficient. Other cations were tested, and we found that Mn++ behaved like Mg++. The Ca++ data suggest that no conventional “stimulus-secretion” process is operative in non-T cell-mediated cytolysis of antibody-coated sheep red blood cells.
The Role of Macrophages in the Production of Lymphokines by T and B Lymphocytes
Authors: Wahl Sharon M. , Wilton J. Mark , Rosenstreich David L. , Oppenheim Joost J.
Published: December 2022

The role of macrophages in the production of two lymphokines, monocyte chemotactic factor and macrophage activating factor, was investigated. Lymphokine production by guinea pig lymph node and spleen cells required macrophages for thymus-dependent antigens and mitogens. In contrast, B cell stimulants which also induce the synthesis of lymphokines were macrophage independent. When populations of relatively pure B or T lymphocytes were isolated, it was found that T cells required viable macrophage cooperation to produce these two lymphokines and to undergo proliferation in response to specific antigens, whereas B cells could be directly activated in the absence of macrophages. These findings suggest that T and B cells have different requirements for activation and for macrophage cooperation. Furthermore, since lymphokine synthesis is evident within the first 4 hr of stimulant presentation, these observations demonstrate that macrophages play an essential role in the earliest events of lymphocyte activation.
Regulation by Antibody of Phytolectin Induced Lymphocyte Proliferation
Authors: Banks Keith L. , McGuire Travis C.
Published: December 2022

Studies were conducted to determine the mechanisms of antibody suppression of phytohemagglutinin (PHA)- and concanavalin A (Con A)-induced lymphocyte proliferation. Initial experiments incubated lymphocytes with either PHA or Con A, and at various times the respective anti-phytolectin was added to the cultures. DNA synthesis was less than 20% of the total response if anti-PHA was added within 2 hr and if anti-Con A was added within 10 hr of addition of mitogens to the culture. At the concentrations used, anti-PHA reduced PHA binding to the lymphocytes, while anti-Con A did not reduce Con A binding to the cells. Antibody was non-toxic and specific for its respective mitogen. Additional experiments incubated lymphocytes with either PHA or Con A and then the cells were washed and placed in mitogen-free media. The addition of antibody to cultures which had been washed markedly suppressed proliferation. Using radiolabeled PHA and Con A in one group of experiments and fluorescent labeled anti-mitogen antibodies in others, it was determined that antibody did not remove Con A or PHA from the cell, but instead antibody slowed the release of mitogen from the lymphocyte. Anti-mitogen antibody remained attached to mitogen on the surface of lymphocytes for at least 24 hr. The experiments suggest that antibody can suppress the lymphocyte reaction by blocking the necessary phytolectin-lymphocyte interaction and interrupting stimulation by cell-bound mitogen.
Role of the Eosinophil in the Allergic Reactions
Authors: Hubscher Thomas
Published: December 2022

Human eosinophilic leukocytes respond to a variety of stimuli by liberating an inhibitor of histamine release. The active principle(s) in this eosinophil-derived inhibitor (EDI) was found to be a mixture of acidic lipids of similar physicochemical behavior and biologic activity to prostaglandins E1 and E2. Indomethacin, an inhibitor or prostaglandin synthesis, specifically blocked the immune release of EDI.

The results indicate that stimulation of human eosinophilic leukocytes results in synthesis and release of prostaglandins E1 and E2 from these cells. These findings strongly support the hypothesis that the eosinophil assumes a modulatory role in the allergic inflammatory reaction. the ways by which, under specific antigenic (allergenic) stimulation, human eosinophils could modulate the events associated with the allergic response, through the released prostaglandins, are discussed.
The Isolation and Characterization of the VH Domain from Rabbit Heavy Chains of Different a Locus Allotype
Authors: Mole Lawrence E. , Geier Michael D. , Koshland Marian Elliott
Published: December 2022

The Fd fragment of rabbit γ-chains was split by papain to yield a smaller fragment with a molecular weight of approximately 14,000 and dialyzable small peptides and amino acids. The domain size fragment was identified as intact variable region from its amino acid content, its blocked amino-terminus, and two characteristic cysteine-containing peptides, while the small peptides and amino acids were accounted for by the degradation of the CH1 region. The variable regions isolated from Aa1 and Aa3 Fd fragments not only reacted quantitatively with immunoadsorbents conjugated with the homologous anti-a allotype antibody, but also completely inhibited the binding of the parent Fd fragment to the homologous antibody as measured by radioimmune assay. These data provide direct evidence that the group a allotypic determinants are contained entirely in the variable portion and are independent of the constant portion of rabbit heavy chains.
Partial Characterization of a Soluble Antigen Preparation from Cells Infected with Human Cytomegalovirus: Properties of Antisera Prepared to the Antigen
Authors: Waner Joseph L.
Published: December 2022

Soluble antigen (SA) preparations were obtained from cell cultures infected with either the Davis or AD169 strains of cytomegalovirus (CMV). Fractionation of SA preparations through Sephadex G-200 resulted in a molecular weight value ranging from 67,000 to 85,000. Rate-zonal centrifugation produced an approximate value of 5.5S for the CMV antigenic material.

Antisera to SA prepared from either AD169- or Davis-infected cells lacked neutralizing activity but produced specific fluorescence confined to CMV intranuclear inclusion material when used in the indirect fluorescent antibody test (IFA). The specific fluorescing inclusion reaction was seen when either AD169 or Davis antisera were used with cells infected with the Davis, AD169, Kerr, or C-87 strains of CMV. Fluorescence was not observed in cells infected with a strain of Herpes simplex type 1, varicella-zoster virus, an EBV transformed lymphocyte line, the Cx-90-3B human CMV transformed hamster embryo cell line, or CMV-infected cell cultures treated with cytosine arabinoside (Ara-C) and showing only antigens expressed in the absence of viral DNA synthesis. Antisera prepared to SA preparations obtained from CMV-infected cells apparently react with specific CMV antigens that are dependent on viral DNA synthesis and are common to several strains.
Modulation of Cyclic AMP in Purified Rat Mast Cells
Authors: Sullivan Timothy J. , Parker Keith L. , Stenson William , Parker Charles W.
Published: December 2022

The cyclic adenosine 3′,5′-monophosphate (cAMP) content of isolated unstimulated mast cells and the changes induced by a variety of pharmacologic, metabolic, and physical stimuli were studied. A modified bovine serum albumin density gradient purification method consistently provided mast cell preparations which were 95% or more pure, without apparent damage, and a 73% recovery of the mast cells applied to the gradients. The measured cAMP in unstimulated mast cells was high, a mean of 16 picomoles per million cells. Moderate agitation or contact with glass increased cAMP content about 2-fold. When calcium was omitted from the medium mast cell cAMP was markedly elevated; incremental increases in added calcium ion concentration from 1 µM to 1 mM caused a linear decrease in cAMP content. Theophylline (3 to 20 mM) caused a dose-related increase in mast cell cAMP content, approximately 2-fold at 20 mM theophylline. Epinephrine (0.01 to 1 mM) caused a modest, dose-related increase in cAMP. In the presence of theophylline, epinephrine increased cAMP levels equal to or greater than the sum of the effects of the agents used individually. The increase in cAMP induced by epinephrine was completely inhibited by 100 µM propranolol and partially inhibited by 10 µM propranolol, thus suggesting that a β adrenergic receptor is involved. Prostaglandin E1 (PGE1) and histamine (in the presence of theophylline) also raised cAMP. Carbamylcholine (1 nM) lowered cAMP 38%. Atropine (0.1 mM) inhibited the decrease in cAMP induced by 1 nM carbamylcholine by 83% indicating that a muscarinic receptor is involved. In these homogeneous single cell suspensions, therefore, cholinergic and β adrenergic agents have opposing effects on cAMP levels. Diazoxide (10 µM) and adenine (1 µM) caused 37 and 32% decreases in cAMP, respectively. The availability of highly purified mast cells and the identification of agents which either decrease or increase cAMP content allows a direct examination of the role of cAMP in histamine release.
Splenic Regulation of the Clinical Appearance of Small Tumors
Authors: Nordlund James J. , Gershon Richard K.
Published: December 2022

The Cloudman (S91) melanoma elicits an immune response in syngeneic DBA/2 mice which prolongs the time before the tumor becomes detectable but does not significantly alter the growth rate subsequent to its appearance. The spleen can either enhance the immune response and prolong the lag phase when stimulated with high doses of tumor cells or suppress it and shorten the duration at lower doses. This bidirectional effect of the spleen is similar to previously reported activity of regulatory T cells which reside in the spleen. This observation is discussed in contrast to the role of the spleen in animals bearing tumors which elicit concomitant immunity.
Macrophage Activation of Allogeneic Lymphocyte Proliferation in the Guinea Pig Mixed Leukocyte Culture
Authors: Greineder Dirk K. , Rosenthal Alan S.
Published: December 2022

The role of the macrophage in the guinea pig mixed leukocyte culture was investigated. Macrophages obtained from oil-induced peritoneal exudates, peritoneal wash-out cells, spleen, and alveolar washings were found to be effective stimulators of allogeneic lymph node and splenic lymphocyte DNA synthesis. The stimulatory properties of macrophages proved radioresistant but viability dependent. Unfractionated lymph node cells or adherence column purified lymph node lymphocytes and thymocytes were only minimally active as stimulators, even in the presence of macrophages syngeneic to the responder lymphocytes. Allogeneic fibroblasts, polymorphonuclear leukocytes, L2C leukemia cells, and xenogeneic (murine) macrophages failed to stimulate. These data provide evidence that the macrophage is the predominant stimulator of the mixed leukocyte culture in the guinea pig.
Effects of an Acidic Polysaccharide Produced by Serratia Piscatorum on Immune Responses in Mice
Authors: Matsumoto Takao , Shimonishi Chiemi , Ootsu Koichiro
Published: December 2022

An acidic polysaccharide of Serratia piscatorum, consisting of l-rhamnose, d-galactose and d-galacturonic acid, stimulated the primary IgM PFC response of spleen cell cultures against sheep erythrocytes. The polysaccharide (PS) caused dose-dependent stimulation of 3H-thymidine incorporation into DNA of spleen cell cultures and the maximum response was seen after about 48 hr. Nonadherent B (ATXBM) cells were strongly reactive to PS, whereas adherent spleen cells were less reactive.

Higher doses of PS suppressed the peak PFC response, but enhanced the earlier PFC responses. Lower doses of PS stimulated the PFC responses significantly throughout the period of PFC production. The optimal dose (0.1 µg/ml) of PS increased the PFC responses in mixed cell cultures containing spleen cells and either B cells, T cells activated with a different antigen, or hydrocortisone-resistant thymus cells of syngeneic origin. However, this dose of PS interfered with the enhanced PFC response of spleen cells due to addition of antigen-primed T cells. Since these characteristic activities of PS were like those of lipopolysaccharides (LPS), this acidic polysaccharide may be useful for further elucidating the modes of LPS action.
DNP-Lys-Ficoll: A T-Independent Antigen Which Elicits Both IgM and IgG Anti-DNP Antibody-Secreting Cells
Authors: Sharon Raphael , McMaster Philip R. B. , Kask Anne M. , Owens James D. , Paul William E.
Published: December 2022

The 2,4-dinitrophenyl-lysyl derivative of Ficoll (DNP-Lys-Ficoll) was prepared and examined for immunogenicity. This antigen elicited large numbers of DNP-specific plaque-forming cells (PFC) of the IgM and IgG2 class in the spleens of C57BL/6 mice. Similar responses were observed in congenitally athymic (nu/nu) mice and in their littermates indicating that DNP-Lys-Ficoll is a T-independent antigen. The responses of nu/nu mice included a large number of IgG2 DNP-specific PFC, indicating that IgG responses can be initiated in the absence of mature thymus-dependent (T) lymphocytes. Cell transfer studies confirmed the T independence of the response and indicated that priming with DNP-Lys-Ficoll induces only a very meager degree of memory. Because they can be obtained in large quantities and in relatively pure form, DNP-Lys-Ficoll and other hapten conjugates of Ficoll should prove most valuable in the delineation of the mode of activation of precursors of antibody-secreting cells by T-independent antigens.
Release of Mitogenic Factor by Mouse Lymph Node Cells Stimulated with PHA in Vitro. Inhibition of This Phenomenon by the Addition of Thymocytes
Authors: Jacobsson Hans , Blomgren Henric
Published: December 2022

Thymidine uptakes of mouse lymph node cells and thymocytes in response to phytomitogen lectins were investigated in vitro. It was observed that mixtures of lymph node cells and thymocytes yielded higher 3H-TdR incorporations than expected when exposed to concanavalin A (Con A) or pokeweed mitogen (PWM), but lower incorporations than anticipated with phytohemagglutinin (PHA) as a stimulant. The observed enhancement of the response could be explained by factors which are stimulatory for thymocytes released by the lymph node cells. However, such mitogenic factors (MF) were released not only by Con A and PWM exposed cells but also by PHA expose lymph node cells. Further experiments showed that the admixture of thymocytes inhibited the release of MF by lymph node cells exposed to PHA but not to Con A or PWM. Since medullary thymocytes did not exhibit any inhibitory activity, it is likely that cortical thymocytes are responsible for this effect. The mechanism by which thymocytes inhibit MF production of lymph node cells exposed to PHA is not clear. MF was efficiently produced by lymph node cells cultured with PHA in “thymocyte-conditioned” medium and the MF activity was only marginally decreased by absorption with thymocytes.

The results are discussed in the light of recent findings showing that thymocytes may both enhance and depress the immune response of other lymphocytes.
The Role of T Cells in IgG Production; Thymus-Dependent Antigens Induce B Cell Memory in the Absence of T Cells
Authors: Schrader John W.
Published: December 2022

B cell memory was shown to develop in congenitally athymic (nu/nu) mice after injection with small amounts of thymus-dependent antigens, in particular heterologous serum proteins, such as fowl γ-globulin (FGG) or DNP-bovine-serum albumin (DNP-BSA). Large doses of protein (10 mg) tended to produce a specific B cell unresponsiveness, although there was still some evidence of B cell priming. The antigen did not have to be in a multivalent form to interact with B cell so as to induce immunologic memory or tolerance.

In contrast to the induction of B cell memory, the production of IgG antibody in this system was found to be strongly T cell dependent. Thymus-independent antigens like LPS or POL with pronounced adjuvant effects on IgG production in normal or surgically thymectomized mice, could not replace T cells in allowing an IgG response against thymus-dependent antigens in congenitally athymic mice. However, the action of T cells once activated is likely to be non-antigen-specific, since it was shown that supernatants of antigen-activated-syngeneic T cells stimulated IgG production in cultures of primed B cell populations non-antigen-specifically.
Binding of Poly (Glu60Ala30Tyr10) by Thymic Lymphocytes from Genetic Responder and Non-Responder Mice: Effect of Antihistocompatibility Serum
Authors: James Kennedy L. , Dorf Martin E. , Unanue Emil R. , Benacerraf Baruj
Published: December 2022

The binding of 125I-labeled GAT by murine thymocytes was studied by autoradiography. GAT binding was highly temperature dependent. Significantly more thymocytes bound GAT at 37°C than at 4°C. GAT bound at 37°C was usually distributed in a “cap” over one pole of the cell. Preincubation of thymocytes with specific anti-H-2 serum markedly inhibited the subsequent binding of GAT. The frequency of antigen-binding thymocytes was not significantly affected by preincubation of thymocytes with anti-Thy-1 serum or a number of anti-immunoglobulin in sera.

The immune response to GAT is controlled by an H-2 linked immune response gene(s). Mice of strains that are H-2p, H-2q or H-2s (non-responders) fail to develop effective T cell helper function necessary for a humoral immune response to GAT under most conditions. However, both responder and non-responder strains had similar numbers of thymocytes capable of binding GAT in vitro, indicating that T cells from non-responder strains of mice do possess a recognition mechanism for GAT.
Binding Parameters of the Interaction Between Rat IgE and Rat Mast Cell Receptors
Authors: Conrad Daniel H. , Bazin Hervé , Sehon Alec H. , Froese Arnold
Published: December 2022

Rat monoclonal IgE was purified by a combination of gel filtration and isoelectric focusing. The binding parameters of the IgE-target cell interaction were studied. The target cells used were normal rat peritoneal mast cells (RMC) and neoplastic rat basophilic leukocytes (RBL). Binding assays were performed by adding different amounts of IgE to a constant cell number. A Scatchard analysis of the data indicated that both cell types have a similar affinity for rat IgE; the equilibrium constant was in the order of 109 M-1. However, RBL have a higher number of receptor sites per cell—approximately 6 × 105 versus 3 × 105 for normal RMC. Since RMC have more than double the surface area of RBL, the data indicate a much higher receptor density on RBL.
Immunosuppression Induced in Vitro by Mastocytoma Tumor Cells and Cell-Free Extracts
Authors: Kamo Isao , Patel Chandu , Kateley John , Friedman Herman
Published: December 2022

Suppressed anti-sheep RBC responses occurred when spleen cells from mastocytoma-bearing mice were incubated in vitro and immunized with red blood cells. Marked immunosuppression also occurred when mastocytoma cells were added to spleen cell cultures from normal mice immunized in vitro with the sheep RBC. Suppressed immune responses also occurred when the mastocytoma cells were separated from the normal cells by 0.4-µ nucleopore membranes, but not by dialysis membranes in double chambered culture vessels. Cell-free homogenates prepared from mastocytoma cells, as well as ascitic fluid from tumor-bearing mice, also impaired the responsiveness of normal splenocytes to the SRBC. The suppressive activity of the cell-free homogenates was abolished by heating at 56°C for 30 min. The immunosuppressive activity, however, was retained in supernatant ultracentrifugates of the cell-free homogenate after 100,000 × G for 90 min. Immuno-suppression was most evident when mastocytoma extracts were added to cultures of normal splenocytes at the time of in vitro immunization and culture initiation. Suppression was not reversed by washing of the cultured cells and addition of fresh medium. Immunosuppression also occurred when mastocytoma extracts were incubated with spleen cells from allogeneic tumor resistant C57BL/6 mice. Additional physicochemical analyses should provide information as to the nature and specificty of the inhibitory factor(s) and its role as an immunoregulatory substance important in the host-tumor relationship.
Hepatitis B Core Antigen
Authors: Moritsugu Yasuo , Gold Jon W. M. , Wagner JoAnn , Dodd Roger Y. , Purcell Robert H.
Published: December 2022

Radioactive cores were prepared from concentrated Dane particles by DNA polymerase reaction followed by CsCl density gradient centrifugation. Two radioactive peaks were obtained: one peak with an average density of 1.36 g/cm3 in CsCl contained cores that possessed full serologic reactivity; the other peak, with a density of 1.28 to 1.32 g/cm3, contained cores associated with globulin. A double antibody immunoprecipitation test was developed, using the radioactive heavy cores as a source of antigen. The test was at least 300 times as sensitive as complement fixation for detecting antibody to core.
Thymus-Dependent Sensitizing Processes Involved in the Induction of CNS Disease in Mice by Parainfluenza Type 1 Virus
Authors: Iwasaki Y. , Aden D. , Koprowski H.
Published: December 2022

Parainfluenza type 1 virus injected intracerebrally into adult mice induced a mononuclear cell infiltration in the subarchnoidal and perivascular spaces, exudation of inflammatory cells into parenchymal tissue and preferential chronic degeneration of white matter (1, 2). No correlation was found between the severity of the central nervous system (CNS)2 lesions and the levels of circulating hemagglutination inhibition antibody (2). Inactivation of the virus by ultraviolet light (UV) did not affect the ability of the virus to produce the CNS lesions in these mice (3).

As part of an inquiry into the mechanisms involved in the production of CNS lesions, the present study reports the response of athymic nude mice and sensitization through prior CNS exposure to virus antigen in immunocompetent mice.

Materials and Methods. Inocula. The 6/94 strain of parainfluenza type 1 virus, originally isolated from cell cultures of brain tissue from two multiple sclerosis patients (4), was propagated in embryonated hen's eggs.
Endotoxin-Stimulated Spleen Cells: Characterization of the Responding Cells
Authors: Gormus Bobby J. , Shands Joseph W.
Published: December 2022

The percentage of endotoxin-stimulated lymphoblasts possessing C3 receptors (CR) decreases during a 72-hr period of in vitro cultivation. In studies reported here we attempted to determine whether the drop in the percentage of CR+ blast cells resulted from receptor loss by transformed cells or whether it resulted from the proliferation of additional blast cell types which lacked the CR.

Using methods which permitted simultaneous detection of cytoplasmic IgM, the presence of the CR, and 3H-thymidine uptake we found that: a) LPS stimulation resulted in a progressive increase in the number of IgM+ blasts, b) these constituted approximately 30% of the total cell population at 72 hr after LPS stimulation, c) of the IgM+ blasts 72 to 84% were CR+ and 16 to 28% were CR- at 72 hr, d) from 48 to 72 hr there was no decrease in the percentage of IgM+ blasts possessing the CR, and e) an additional blast cell type was observed which incorporated 3H-thymidine but which was IgM- and lacked the CR. These cells constituted from 11 to 27% of total 3H-thymidine+ cells at 72 hr after LPS stimulation. We conclude that the decrease in the percentage of CR+ blasts in LPS-stimulated spleen cell cultures is not due to receptor loss from IgM+ blasts cells but apparently is partly due to the stimulation and proliferation of other cell type(s) which lack(s) the CR. This cell(s), although its functional identity is unknown, does not appear to be of thymic origin. The heterogeneity of the markers on LPS-stimulated blast cells suggests that a heterogeneous population of cells responds to LPS.
Radiosensitivity of T and B Lymphocytes
Authors: Anderson Robert E. , Warner Noel L.
Published: December 2022

Radiation injury in defined populations of B cells was investigated utilizing an allotype congenic transfer system. The amount of donor immunoglobulin present in the recipient's serum was found to be directly proportional to the number of viable cells injected, and on this basis approximate D37 values for the inoculated B cells were determined in several experiments and found to fall in the 70 to 145 rad range depending upon the specific experimental conditions. Since the sensitivity of T cells to radiation-induced interphase death can be modified by prior exposure to select mitogens and antigens, an attempt was made to demonstrate a similar phenomenon with respect to B cells. The results indicate that the radiosensitivity of B cells can be slightly influenced by prior incubation with mitogens and only equivocally changed by activation with antigen.