bluuebunny/crossref_metadata_2025 huggingface dataset:
Opposing Effects of Cryostat Sections of Preneoplastic and Neoplastic Mouse Mammary Lesions on in vitro Migration of Peritoneal Exudate Cells
Authors: Wei Wei-Zen , Miller Fred R. , Blazar Beverly A. , Medina Dan , Heppner Gloria
Published: December 2022

Cryostat sections of normal mouse tissues and of preneoplastic HAN and neoplastic mammary tumors were used as “antigens” in MMI tests. Nonspecific inhibition of normal and sensitized PEC migration was induced by HAN and some normal tissues, including normal mammary gland. This inhibition did not require the presence of lymphocytes, was not species specific, and could be blocked by sera from HAN-bearing mice. Cryostat sections of mammary tumors did not inhibit, indeed occasionally enhanced PEC migration. Further, the presence of tumor cryostats and eluates interfered with inhibition induced by HAN cryostats and by PPD with PEC from donors sensitized to that antigen. Histologic examination of HAN and of mammary tumor tissue revealed inflammatory cells to be distributed diffusely in the former and localized peripherally around the latter type of lesion.
Defective Resistance to Plasmodium Yoelii in CBA/N Mice
Authors: Hunter Kenneth W. , Finkelman Fred D. , Strickland G. Thomas , Sayles Peter C. , Scher Irwin
Published: December 2022

The role of B lymphocytes in resistance to malaria was studied in defective and normal F1 mice derived from CBA/N mice, a strain with an X-linked B cell defect. When infected with normally nonlethal Plasmodium yoelii, immune defective F1 male mice had higher parasitemias and more prolonged infections than normal F1 mice, as well as a 50% mortality rate. Before infection the plasma levels of IgM and IgG were lower in defective F1 males than normal F1 mice. The polyclonal IgM and IgG responses of infected abnormal F1 mice were delayed and lower in absolute magnitude than those of normal F1 mice. Furthermore, specific IgM and IgG anti-plasmodial antibody titers, as determined by radioimmunoassay, were depressed on day 12 in the defective F1 males. Although IgG titers approached those of the normal F1 mice on day 19, defective F1 male IgM titers remained depressed. These data demonstrate that an X-linked gene that affects B cell function influences malarial resistance in mice, presumably via a decreased specific IgM response, and the slow development of a specific IgG response to P. yoelii infection.
Regulation of Autoimmune Response to Mouse Thyroglobulin: Influence of H-2D-end Genes
Authors: Kong Yi-Chi M. , David Chella S. , Giraldo Alvaro A. , Elrehewy Mostafa , Rose Noel R.
Published: December 2022

Studies were initiated to define the H-2-linked genetic control of response to self-determinants of MTg. In addition to the Ir gene control of H-2K end, a modifying effect of D end was seen. The extent of regulation depended upon the derivation of the K-end Ir-Tg gene(s) as well as the D-end genes. When the Ir-Tg gene was from good responder H-2k and H-SS strains, and the H-2D-end gene from the d allele, antibody levels were moderate to high but cellular infiltration was significantly reduced. These findings demonstrate genetic interaction between I-region and D-end gene products in the response to a self-antigen, MTg.
Soluble Factors Containing Thy-1 Antigen Shed from Lymphoblastoid Cells Modulate in vitro Plaque-Forming Cell Response
Authors: Freimuth W. W. , Miller H. C. , Esselman W. J.
Published: December 2022

Culture media from two lymphoblastoid cell lines, BW 5147 (Thy-1.1, H-2k) and S.49.1 (Thy-1.2, H-2d), were capable of suppressing approximately 50% of the primary in vitro anti-SRBC hemolytic plaque response of BALB/c (Thy-1.2, H-2d) and AKR (Thy-1.1, H-2k) spleen cell cultures. The association of the Thy-1 molecule with the suppressor factor was suggested when pretreatment of both of these conditioned media with either anti-Thy-1.1 or anti-Thy-1.2 alloantisera abrogated the modulatory activity. Simultaneous measurement of primary anti-Thy-1.1 PFC responses by the same BALB/c (Thy-1.2, H-2d) spleen cell cultures indicated that only BW 5147 culture medium could induce a significant anti-Thy-1.1 antibody response. In contrast to neutralization of suppressor activity by both anti-Thy-1 alloantisera, only anti-Thy-1.1 sera adsorption of BW 5147 culture medium abrogated the anti-Thy-1.1 PFC response; anti-Thy-1.2 sera either had no effect or enhanced it.

The molecular properties of the suppressor factor and shed Thy-1 were analyzed by column chromatography of culture medium from [3H]glucosamine-labeled S.49.1 and BW 5147 cells. The suppressive activity in culture medium from both tumor cells was found in fractions of high m.w. (>2 × 106 daltons). Immunoprecipitation techniques and the anti-Thy-1 PFC assay were utilized to demonstrate that in both neoplastic cell lines the Thy-1 antigenicity also resided primarily in large m.w. complexes of >2 × 106 daltons. Column fractions containing high m.w. substances from BW 5147 or S.49.1 culture medium, either by themselves or pretreated with anti-Thy-1.1 or anti-Thy-1.2 sera, were cultivated with BALB/c spleen cell cultures and gave results similar to those observed with unfractionated culture medium. These experiments indicate that the suppressor activity found in the conditioned medium of these two lymphoblastoid cells is contained in a high m.w. complex associated with the Thy-1 antigen.
Cross-Neutralization of Infectious Mononucleosis and Burkitt Lymphoma Strains of Epstein-Barr Virus with Hyperimmune Rabbit Antisera
Authors: Coope Donald , Heston Lee , Brandsma Janet , Miller George
Published: December 2022

Antisera that neutralize Epstein-Barr virus (EBV) were prepared in rabbits. Neutralization tests were based on inhibition of transformation of normal lymphocytes into cell lines or on inhibition of induction of early antigen. Supernatant culture fluids of human and marmoset lymphoblastoid cell lines productive of virus were the source of antigen. Neutralizing activity was not induced by immunization of rabbits with medium from EBV transformed cell lines that did not release virus. However, neutralizing activity appeared in the sera of rabbits inoculated with supernatant fluid of a producer line from which nearly all the virions had been removed by ultracentrifugation. Rabbit antisera with neutralizing activity reacted with radioiodinated virus purified by velocity sedimentation on a sucrose gradient.

Neutralizing capacity of the sera was not removed by absorption with primary human or marmoset leukocytes, by absorption with EBV transformed human B lymphoid cells that were not virus producers, nor by absorption with marmoset lymphoblastoid T cell lines transformed by Herpes saimiri virus. However, absorption of the antisera with EB virus producer lines caused a marked reduction or elimination of neutralizing antibody titer.

Cross-neutralization and cross-absorption tests did not indicate the existence of distinct serotypes. Antiserum prepared against the Hawley EBV strain from a patient with mononucleosis neutralized two viruses of Burkitt lymphoma origin, HR-1 and Olare. Antiserum raised against the nontransforming HR-1 strain neutralized the two transforming strains. Absorption of the sera with virus producer cells removed neutralizing activity directed against both homologous and heterologous viruses. The results indicate that EB viruses of diverse origin and diverse biologic properties share antigens, presumably located both on the viral envelope and on the cytoplasmic membrane of producer cell lines, which elicit neutralizing activity.
Regulation of the Primary Immune Response to Ovalbumin in Mice: Activation of T Cells Mediating Delayed-Type Hypersensitivity, Nonspecific Help, and Specific Help, and Their Sensitivity to Radiation
Authors: Lubet Martha Turner , Kettman John R.
Published: December 2022

We have previously shown that the immune response to ovalbumin (OVA) in mice is controlled by at least four genes. The purpose of the studies reported here was to investigate the site of action of the genes regulating the response to OVA. To this end, helper T cell functions were studied in responder (BDF1) and nonresponder (A/J) mice by using three approaches.

In the first approach, the antibody response to limiting and nonlimiting doses of TNP-OVA was studied. When mice were immunized with limiting doses of TNP-OVA, anti-TNP antibodies were elicited but anti-OVA antibodies were not. These findings suggest that OVA-specific helper T cells are not the limiting factor in the anti-OVA antibody responses.

Helper T cell functions were also measured in in vitro assays. Two kinds of helper T cell activity were measured. “Nonspecific” helper T cell activity (the bystander effect) was determined by measuring the ability of OVA-primed spleen cells to help the anti-sheep red blood cells (SRBC) antibody response in cultures stimulated with SRBC and TNP-OVA. Antigen-specific helper activity was determined by measuring the ability of OVA-primed spleen cells to help the anti-TNP antibody response in cultures stimulated with TNP-OVA. The results indicate that in vivo-priming doses of OVA that do not elicit a delayed-type hypersensitivity (DTH) response or a primary antibody response prime for both “nonspecific” and antigen-specific helper T cells. These findings suggest that the genes regulating the immune response to OVA do not control activation of helper T cells.

These T cell subpopulations that recognize OVA can be further distinguished by virtue of their sensitivity to radiation. The DTH effector cells and cells responsible for “nonspecific” help are not sensitive to 1000R. In contrast, the specific helper activity is sensitive to 1000R. The subsets that are not sensitive to radiation are distinguished by their independent activation by OVA.
Changes in Receptor Isotype and T/B Ratio in an Antigen-Binding Cell Population after in vitro Immunization
Authors: Merrill Jean E. , Ashman Robert F.
Published: December 2022

T and B antigen-binding cells (T ABC, B ABC) specific for sheep erythrocytes (SRC) have been generated in a primary in vitro Mishell-Dutton-type culture system. On days 1 to 3 of the in vitro response, ABC were approximately 60% T cells and 40% B cells, although on days 4 to 6 there were more B ABC than T ABC. T ABC increased significantly in the first day of culture, but no increase in B ABC was seen until day 3. Absolute numbers of both T and B ABC were maximal on day 4, representing a 10-fold increase in T ABC and about a 4-fold increase in B ABC.

The increase in T and B ABC was antigen-driven. In unstimulated cultures, T and B ABC maintained nonimmune levels until day 4. However, T and B non-ABC decreased synchronously, whether antigen-stimulated or not.

The isotypes of ABC receptors were examined by inhibiting antigen binding with heavy chain-specific antisera. All ABC, including T ABC, were inhibitable by rabbit anti-mouse immunoglobulin (RxMIg) containing antibodies to γ, µ, κ, and λ. The proportion of ABC inhibitable by anti-µ did not change from the day 0 level in antigen-stimulated or unstimulated cultures. There was an antigen-driven gain of surface IgG (sIgG) by ABC between day 2 and day 3 in stimulated cultures not seen in unstimulated cultures. Loss of surface IgD (sIgD) occurred to the same extent and at the same rate from ABC in stimulated and unstimulated cultures, providing no conclusive evidence that this loss was an antigen-driven differentiation event, but demonstrating that the loss of sIgD could be dissociated from the expression of sIgG. On day 3, when sIgG first appeared, it was expressed mainly or exclusively on surface IgM (sIgM)-bearing cells, the majority of which still expressed sIgD.
Lymphocytes Bearing Fc Receptors for IgE
Authors: Yodoi Junji , Ishizaka Teruko , Ishizaka Kimishige
Published: December 2022

The proportion of lymphocytes bearing receptors for IgE (FcεR) markedly increased after infection of rats with Nippostrongylus brasiliensis (Nb). The FcεR-bearing lymphocytes from the infected animals bound more IgE-coated erythrocytes in rosette assay than FcεR-bearing cells from normal rats, suggesting that the number of FcεR per cell may also increase following the infection. In contrast, the number of IgE-receptors on peritoneal mast cells did not change after Nb infection. The increase in the proportion of FcεR-bearing lymphocytes in Nb-infected rats is probably due to an increased concentration of IgE in the environment. The proportion of FcεR-bearing cells in normal rat lymphocyte suspensions increased by culture of the cells with rat IgE of 1 µg/ml or higher concentration. Other immunoglobulins such as rat IgG, human IgE, or rabbit IgG failed to induce either FcεR-bearing cells or FcγR-bearing cells. It was also found that induction of Fc receptors by rat IgE is confined to FcεR. Kinetic studies on the induction of FcεR-bearing lymphocytes in vitro showed that the proportion of these cells in lymphocyte suspensions increased within 8 hr incubation with rat IgE but not within 4 hr. Evidence was obtained that both RNA synthesis and protein synthesis, but no DNA synthesis, are required for the induction of FcεR-bearing cells or the expression of the receptors on the cell surface.
Immune Response Gene Control of Determinant Selection
Authors: Rosenwasser Lanny J. , Barcinski Marcello A. , Schwartz Ronald H. , Rosenthal Alan S.
Published: December 2022

The genetic control of the murine T cell proliferative response to insulin was examined. It was found for two responder strains of mice that each recognizes a different determinant on the insulin molecule. H-2b mice recognize a determinant in the A chain loop of insulin whereas H-2d mice recognize a determinant that resides in the B chain, possibly in the last eight amino acids. Using H-2 recombinant strains of mice, the location of Ir gene control of the response to both determinants was mapped to the K region and/or I-A subregion of H-2. The possibility of non-MHC regulation of MHC-controlled immune responses is suggested by studies of recombinant inbred strains of mice.
Carrier Effect During the Course of Experimental Schistosomiasis: Suppression of the Response to TNP-Schistosomula in Rats and Inbred Mice
Authors: Ramalho-Pinto F. Juarez , Smithers S. Ronald , Playfair John H. L.
Published: December 2022

The helper T cell response of the mouse and rat to infection with Schistosoma mansoni was measured by using schistosomula as a carrier for the hapten TNP. After infection, both hosts showed a high level of helper T cell activity with a peak response between 8 to 10 days after exposure to cercariae. As infection progressed and protective immunity developed, there was a steady decline in the level of helper T cell activity as detected by the anti-TNP assay, and the response could not be restimulated by a second infection. Mice vaccinated with 30 formalin-fixed schistosomula gave a helper T cell response equivalent to that of infected mice, but their response remained at a high level for at least 24 weeks. Antibody to schistosomula was detected in the serum of mice 5 weeks after infection and reached high titers by week 11; no antibody was detected in vaccinated mice. The passive transfer of serum from 8- to 13-week infected mice reduced the PFC response after injection of TNP-schistosomula in 8- to 10-day infected mice and in vaccinated animals, suggesting that anti-carrier antibody was responsible for the depression of helper T cell activity. IgG purified from the serum of 16- to 17-week infected mice by affinity chromatography with a Sepharose-protein A gel specifically suppressed T cell cooperation to the schistosomular surface. The decline in helper T cell activity in schistosome-infected mice may not indicate a decrease in the number of helper T cells to schistosomula in chronically infected animals, but could reflect the blocking by anti-carrier antibody of the cooperation between T cells and the hapten-committed B cells.
Suppression of the in Vitro Secondary Response to Syngeneic Tumor and of in Vitro Tumor Therapy with Immune Cells by Culture-Induced Suppressor Cells
Authors: Greenberg Philip D. , Cheever Martin , Fefer Alexander
Published: December 2022

Mice with advanced disseminated syngeneic tumor can be successfully treated with a combination of chemotherapy and adoptively transferred syngeneic immune cells. We have previously demonstrated that in vivo primed cells secondarily sensitized in vitro became more effective in tumor therapy, whereas primed cells cultured for 5 days without tumor stimulation became less effective than an equal number of uncultured fresh primed cells. Therefore, we examined stimulated and unstimulated cultures of tumor-primed cells for the presence of culture-induced suppressor cells, and determined whether in vivo tumor therapy with immune cells could be inhibited by concurrent inoculation of immune effector cells and cultured normal spleen cells, which contain culture-induced suppressor cells but are devoid of additional effector cells.

The in vitro primary allogeneic response was suppressed by cultured normal spleen cells, or tumor-primed spleen cells previously cultured for 5 days with or without tumor stimulation. In vitro secondary sensitization to syngeneic tumor was suppressed by normal or tumor-primed cells that had previously been cultured for 5 days without stimulation. The majority of this suppression was mediated by T cells in the cultured populations.

The efficacy of fresh tumor-primed cells, as well as primed cells secondarily sensitized in vitro, in adoptive chemoimmunotherapy of advanced tumor was diminished by concurrent inoculation of cultured normal cells. The cells mediating suppression of in vivo therapy required previous in vitro culture for induction, and were radiation sensitive.
Complement Receptor Binding of C3b-Coated Cells Treated with C3b Inactivator, β1H Globulin and Trypsin
Authors: Carlo Jaime R. , Ruddy Shaun , Studer Elaine J. , Conrad Daniel H.
Published: December 2022

Treatment of 125I-C3b bound to EAC1423b with C3b inactivator (C3bINA) and β1H globulin (β1H) cleaved the α-chain of C3b into 65,000- and 42,000-dalton fragments, both of which remained disulfide-bonded to the intact β-chain (C3bi). Subsequent treatment with trypsin (0.1 µg/ml) released 125I into the supernatant and yielded cells coated with a 33,000-dalton fragment of α-chain, presumably C3d. These results are in agreement with those obtained by others using fluid phase C3b. C3b-coated cells (EAC1423b) adhered to complement (C) receptors on human erythrocytes, glomeruli, and monocytes. C3bi-coated cells adhered to the receptors on glomeruli and monocytes, but not to those on human erythrocytes. C3d-coated cells adhered only to the monocyte receptors. The findings suggest that the glomerular C receptor recognizes portions of the C3 molecule different from those recognized by either the erythrocyte or monocyte receptors.
Selective Localization of Radiolabeled Immune Lymphocytes into Syngeneic Tumors
Authors: Mulé J. J. , Jones F. R. , Hellström I. , Hellström K. E.
Published: December 2022

Newly formed long-lived small lymphocytes (LLSL) generated during the immunization of mice to tumor specific transplantation antigens (TSTA) of syngeneic MCA-induced sarcomas were labeled. We then studied the localization of these labeled cells into tumor implants. “Criss-cross” experiments were performed in which MCA sarcomas with individually distinct TSTA were studied in parallel. A selective localization of LLSL into tumors to which the lymphocytes were immune was found when small tumor pieces were implanted into immune mice whose LLSL had been labeled. Selective localization was also detected upon adoptive transfer of immune LLSL to tumor-bearing mice, but only when these mice had, before transfer, received a sublethal dose of whole body irradiation.
T-T Interactions in the Induction of Antigen-Specific Human Suppressor T Lymphocytes in Vitro
Authors: Uytdehaag Fons , Heijnen Cobi J. , Pot Kees H. , Ballieux Rudy E.
Published: December 2022

We intended to investigate whether the suppression of antigen-induced antibody responses in vitro in man by T suppressor cells required contact of T suppressor cells with target cells or whether this effect was mediated by factors released by T suppressor cells. To this end supernatants of antigen-induced T suppressor cells were tested (by a plaque forming cell assay) for their capacity to suppress antibody responses of autologous and allogeneic human peripheral blood lymphocytes.

We have shown that supernatants of antigen-specific T suppressor cells, designated as TsF24: a) can suppress an antibody response of autologous but not allogeneic lymphocytes to the inducing antigen; b) are antigen-specific in their effect; and 3) are produced by radiosensitive T cells. Furthermore, the target of the factor is a radiosensitive T cell. These findings taken together indicate that, in the generation of T-effector suppressor cells in man, T-T interactions occur, and in addition, that cellfree factors may be involved in these interactions.
Immunoglobulin Classes Implicated in Intestinal Disturbances of Calves Associated with Soya Protein Antigens
Authors: Barratt Michael E. J. , Porter Philip
Published: December 2022

Calves fed diets containing soya protein develop high levels of serum antibody mainly of the IgG1 class which precipitates antigen and fixes complement. Passively acquired maternal antibody is associated with a significantly elevated response, and delaying the introduction of the soya antigen from 1 week to 4 weeks of age is associated with a significant decrease in the response.

Very few calves, 3 out of 80, were found to display classical signs of immediate-type hypersensitivity to dietary soya protein. One calf, however, exhibited extreme sensitivity, with demonstrable localized anaphylaxis and PCA in recipient calves. This calf was examined in greater detail in terms of its intestinal antibody response and compared with calves exhibiting the IgG1 complement-fixing precipitin reaction which occurs as the “conventional” response to the antigen in all calves fed on the soya protein.

A rationale for the surprising level of serum antibody response to the dietary antigen is based on current hypotheses relating to the cooperative action of gastrointestinal antibodies and enzymes. Examination of the immunoglobulin classes present in the secretions of Thiry Vella loops demonstrated a low level of specific antibody associated with IgM and IgA classes. Perfusion of the loops with soya protein extracts resulted in a dramatic release of antibody activity in the hypersensitive calf with a change of specific activity to the IgG class. This antibody secretion coincided with the detection of a transient homocytotropic antibody response in the loop secretion. In calves exhibiting the “conventional” IgG1 blood serum antibody response, insignificant amounts of antibody of any immunoglobulin class were released into the lumen.
The Requirement for Macrophages in the Augmentation of Natural Killer Cell Activity by BCG
Authors: Tracey Daniel E.
Published: December 2022

Intraperitoneal injection of BCG gives rise to a rapid augmentation of peritoneal natural killer (NK) cell activity in mice. Depletion of macrophages in vivo by injection of silica particles markedly diminished BCG-induced NK cell augmentation. In contrast, short-term in vitro treatment of BCG-induced peritoneal exudate cells (BCG-PEC) with silica did not affect NK cell activity, despite considerable toxicity to macrophages. The mechanism of BCG-induced enhancement of NK cell activity was evaluated with an in vivo inductive transfer system. Intraperitoneal transfer of BCG-PEC, but not normal peritoneal cells, induced cytotoxic activity in recipient PEC as measured 1 to 10 days later. That this cytotoxic activity was due to NK cells was shown by their lability at 37°C and by their adherence properties. Macrophages were required for the induction of NK cell augmentation, as it was shown that 3-day BCG-PEC depleted of phagocytic cells, adherent cells, or Fc receptor-bearing cells failed to induce NK activity. Furthermore, cell-free supernatants of 24-hr cultures of 3-day BCG-PEC were also active in inducing NK cell enhancement in vivo. These results suggest that the augmentation of NK cell activity by BCG involves cell-derived soluble factors and it requires macrophages during the induction phase, but not for the lytic expression of NK cells.
Killing of Schistosomula of Schistosoma mansoni by Normal Human Monocytes
Authors: Ellner Jerrold J. , Mahmoud Adel A. F.
Published: December 2022

All mammalian species exhibit some degree of innate resistance to infection with the helminth Schistosoma mansoni. This is manifest experimentally by the discrepancy between the number of infecting cercariae and the resulting mature worm load (1). Even in the most susceptible species, such as the hamster and mouse, no more than 40 to 60% of infecting organisms develop into adult worms (2). In vitro systems have been used to elucidate potential mechanisms of schistosomula killing (3–8). However, the recognized mechanisms all are predicated upon prior schistosomiasis with the development of specific antibodies (3, 4), the availability of eosinophils (5–7), or activation of macrophages (8). The current studies were designed to evaluate possible contributions of circulatory leukocytes to naturally occurring resistance to schistosomiasis. They show that cells derived from circulatory human monocytes can kill schistosomula independent of specific antibody and complement (C).

Materials and Methods. Cell preparations.
Characterization of a Spontaneous Murine B Cell Leukemia (BCL1)
Authors: Knapp M. R. , Severinson-Gronowicz E. , Schröder J. , Strober S.
Published: December 2022

A spontaneous BALB/c B lymphocyte leukemia could be stimulated in vitro by the polyclonal B cell activator lipopolysaccharide (LPS) and the conditions for activation were studied. Spleen cells or peripheral blood lymphocytes from tumor-bearing animals responded by increased DNA synthesis and the peak of activation occurred earlier than with normal mouse spleen cells. Tumor cells harvested from the spleen, but not from the peripheral blood, could be induced by LPS to secrete IgM. Direct demonstration that the response was due to tumor cell activation and not that of contaminating normal B lymphocytes was provided by karyotype analysis and by immunoprecipitation, which showed the restriction of light chains on secreted IgM molecules to the λ isotype.
The Ability of the Murine Placenta to Absorb Monoclonal Anti-Fetal H-2K antibody from the Maternal Circulation
Authors: Wegmann Thomas G. , Mosmann Timothy R. , Carlson George A. , Olijnyk Orysia , Singh Bhagirath
Published: December 2022

One of the major unresolved questions in transplantation immunology is the mechanism that prevents the mother from rejecting her allogeneic offspring in utero (1). A number of investigators have proposed that the placenta could serve as a histocompatibility antigen-containing immunoabsorbent barrier between mother and fetus, preventing potentially harmful maternal antibodies from reaching the fetus (2–7). We have recently obtained direct evidence for this by injecting partially-purified radiolabeled antibodies directed against the paternal strain H-2 haplotype into the maternal circulation during pregnancy (6, 7). We found that the antibody differentially accumulated in the placenta exclusively, and only when the fetus bore the target H-2 haplotype, although the exact component(s) of H-2 being recognized was not defined. Fetectomy experiments ruled out the fetal circulation as an immediate source for the immunoabsorbent effect.

In this communication we report confirmation of these findings by using a highly purified monoclonal antibody directed solely against a K region antigen coded for by the fetal H-2 haplotype.
The Carboxy-Terminal Peptides of in vitro Precursor and in vivo Mature κ Light Chains Are Identical
Authors: Rose Stephen M. , Kuehl W. M.
Published: December 2022

Protein structural analysis of several precursor light chains indicates that these in vitro products include a cysteine-containing tryptic peptide that is indistinguishable from the carboxy-terminal tryptic tripeptide present in in vivo mature κ light chains. It is concluded that although in vitro precursor light chains contain an additional amino-terminal sequence, their carboxy-terminus is the same as that found in in vivo mature light chains.
Structural Similarities between C6 and C7 of Human Complement
Authors: Podack Eckhard R. , Kolb William P. , Esser Alfred F. , Müller-Eberhard Hans J.
Published: December 2022

A new method for the isolation of C6 and C7 by affinity chromatography of human serum with anti-C6 and anti-C7 coupled to Sepharose is described. C6 and C7 prepared by this method are hemolytically fully active, homogeneous proteins obtained in 25% yield. A comparison of the properties of isolated C6 and C7 gave the following results: The amino acid composition of the two proteins is very similar. The m.w. calculated from the amino acid content is 124,800 for C6 and 120,800 for C7. Both components are single chain glycoproteins migrating upon electrophoresis at pH 8.6 as β2-globulins. Both proteins are polymorphic as detected by isoelectrofocusing in polyacrylamide gels and range in their isoelectric points from pH 6.15 to 6.7. The UV spectra reveal only minor differences; the extinction coefficients are: EC6 = 1.71 cm2 × mg-1 and EC7 = 1.92 cm2 × mg-1. CD-spectra show 8% α-helix and 10% β-structure for C6 and 10% α-helix and 14% β-structure for C7. The structural similarities of C6 and C7 suggest their evolution from a common ancestral gene.
Experimental Allergic Encephalomyelitis in the Lewis Rat: Studies on the Mechanism of Recovery from Disease and Acquired Resistance to Reinduction
Authors: Willenborg David O.
Published: December 2022

Experimental allergic encephalomyelitis (EAE) in the Lewis rat is an acute, self-limiting disease. Rechallenge of convalescent rats shortly after recovery leads to the reinduction of a mild, brief clinical episode. With increasing time after primary sensitization, rats become resistant to reinduction of both clinical and histologic signs of EAE. Convalescent rats that are resistant to reinduction of disease retain specific antigen-reactive cells, as evidenced by the ability of their lymphocytes to response in vitro to basic protein (BP). Spleen cells from convalescent rats can be used to reconstitute the lymphomyeloid apparatus of lethally irradiated rats. These reconstituted rats develop EAE in a normal fashion. These experiments provide evidence against clonal deletion as the mechanism of recovery from and resistance to reinduction of EAE and suggest the operation of an active suppressor mechanism. Although resistant to active reinduction of disease, convalescent rats do not appear to represent a suppressive environment for passive induction of disease. Sensitized lymphocytes capable of inducting EAE in naive recipients are not inactivated when transferred into convalescent recipients. The passively induced disease in convalescent rats is equal in severity to disease in naive recipients but shows a difference in the distribution of lesions with involvement of the cerebellum in the former but not the latter.
Role of Lipids in the Immune Response
Authors: Wolf Raoul L. , Merler Ezio
Published: December 2022

Lymphocyte mitogenic factor (LMF) is a lymphokine produced by dividing T cells. An activity coeluting with LMF from a Sephadex resin is extractable from LMF with chloroform-methanol. It enhances but does not initiate antibody formation measured by generation of plaque-forming cells (PFC). It does not cause proliferation of B cells. This activity elutes from a silicic acid column and produces a pattern on thin layer chromatography that suggests that the compound(s) responsible for the activity is a polar lipid.
The Cytolytic T Lymphocyte Response to Trinitrophenyl-Modified Syngeneic Cells
Authors: Finberg Robert , Burakoff Steven J. , Benacerraf Baruj , Greene Mark I.
Published: December 2022

The subcutaneous administration of trinitrophenyl (TNP)-coupled syngeneic cells 7 days before co-culture with TNP-coupled syngeneic stimulator cells results in increased cytolytic activity. This augmented cytotoxic response has been shown to be dependent, at least partially, on radioresistant “helper” T cells. In this paper we have demonstrated that TNBS-generated suppressor T cells that are capable of suppressing contact sensitivity can specifically suppress the augmented response seen after subcutaneous priming. The i.v. administration of TNP-coupled cells results in priming of the recipient; however, if cells from these animals are transferred to a second recipient, there is evidence of suppressor activity. Thus, the cytotoxic T lymphocyte response is controlled by the same type of complex interactions previously demonstrated for humoral and delayed-type hypersensitivity responses.
Cell-Mediated Immune Response to Syngeneic UV-Induced Tumors
Authors: Woodward Jerold G. , Daynes Raymond A.
Published: December 2022

Both I-A and I-E subregion-coded antigens were shown to be present on the accessory cell required for a tumor immune response in vitro. Draining lymph node (DLN) cells from mice immunized in the hind footpad with tumor cells proliferate and differentiate into cytotoxic T lymphocytes (CTL) after 4 days in vitro. Both proliferation and differentiation of CTL activity in vitro require the presence of an adherent, radioresistant, Thy-1 negative and Ia-positive accessory cell. The pretreatment of DLN cells with anti-Iak antisera + C caused a marked reduction in accessory cell function that was restored upon addition of 1000 rad irradiated DLN or spleen cells. Absorption experiments demonstrated that removal of both I-A and I-E subregion specificities from anti-Iak antisera was necessary to deplete the antisera of cytotoxic activity against DLN accessory cells. Antisera specific for the A, B, and J subregions as well as antisera specific for the J, E subregions or E, C subregions were also effective at removing accessory cell activity from DLN cells. One of these antisera possessed activity against only specificity Ia.7 of the Ek haplotype, suggesting the expression of Ia.7 on the accessory cell. Antigens coding in the I-J subregion could not be detected when an antiserum with known anti-suppressor cell activity was used. These results suggest the expression of I-A and I-E subregion-coded antigens on the accessory cell, and data are presented indicating that both antigens are expressed on the same cell.
Immunoglobulin Synthesis in the Lungs and Caudal Mediastinal Lymph Node of Sheep
Authors: Gorin Arnold Bernard , Gould John
Published: December 2022

The ratio of the lymph and plasma concentrations of a protein is inversely proportional to the log of its m.w., unless the molecule is locally secreted. To determine the quantity of immunoglobulin synthesized in the lung and mediastinal lymph nodes, we measured immunoglobulin levels in the plasma and lung lymph of 15 adult sheep.

The caudal mediastinal lymph node (CMLN) receives afferents from both lungs, but not from the major bronchi or trachea. We cannulated the CMLN efferent duct at least 3 days before sample collection. We obtained simultaneous plasma and lung lymph samples under baseline conditions (presence of a normal pulmonary capillary permeability to albumin and lymph flow of 4 to 6 ml/hr). Concentrations of IgA, IgG, and IgM in all samples were measured by radial immunodiffusion. Concentrations of albumin, ceruloplasmin, and fibrinogen were measured chemically.

Our results yielded plasma levels of IgA (0.34 mg/ml), IgG (22.89 mg/ml), and IgM (3.70 mg/ml) in the normal range for sheep. The concentration of the measured proteins in lymph was that predicted by diffusion from plasma, except for IgA and IgM. The lymph/plasma concentration ratios for IgA (1.46) and IgM (0.41) were greater than predicted for a diffusion model by factors of 3 and 2, respectively. From our data we conclude that >56 mg of IgA and >128 mg of IgM are synthesized in the lower respiratory tract or CMLN and returned to the circulating immunoglobulin pool each 24 hr. This represents 10 to 15% of the total daily synthesis of both these classes. We found no evidence of IgG secretion in the distal lung under baseline conditions.
Ontogeny of Terminal Deoxynucleotidyl Transferase-Positive Cells in Lymphohemopoletic Tissues of Rat and Mouse
Authors: Gregoire Kathleen E. , Goldschneider Irving , Barton Randall W. , Bollum F. J.
Published: December 2022

The ontogeny of hemopoietic cells which contain the enzyme terminal deoxynucleotidyl transferase (TdT) was studied in rats and mice. During fetal life, TdT-positive cells were first detected in the thymus, where they appeared on or about day 17 of gestation. TdT-positive cells were not found in fetal liver, spleen, or bone marrow, but appeared in bone marrow and spleen on the day after birth. In the rat, peak levels of TdT-positive cells were attained at 3 to 4 weeks of age in thymus, bone marrow, and spleen, accounting for 67, 3.9, and 2.3% of nucleated cells, respectively. The percentages of TdT-positive cells in thymus and bone marrow decreased gradually thereafter, whereas TdT-positive cells in spleen were no longer detectable by 7 weeks of age. Normal percentages of TdT-positive cells were found in bone marrow and spleen from neonatally thymectomized rats and congenitally athymic (nu/nu) mice. Dexamethasone treatment resulted in a marked decrease in TdT-positive cells. The results are discussed with respect to the putative role of TdT-positive hemopoietic cells as thymocyte progenitors.
Studies on the Kinetics of Hemopoietic Stem Cells and Immune Responses to the Hapten-Carrier Conjugate
Authors: Hamano Teruaki , Kai Shunro , Fujita Shigeru , Nagai Kiyoyasu
Published: December 2022

The correlation between the kinetics of hemopoietic stem cells and immune responses to the hapten-carrier conjugate was investigated. The numbers of both pluripotent stem cells (CFU-S) and myeloid stem cells (CFU-C) in the spleen from mice immunized with the hapten-carrier conjugate were significantly greater than those of the control and the activity of colony-stimulating factor (CSF) in the serum of these mice was markedly elevated. The supernatant of short-term incubation of splenic T lymphocytes from these mice, when stimulated with carrier protein, had high levels of both activities of CSF and helper T cell factors. The study by gel chromatography showed that these factors are similar m.w. substances of 35,000 to 45,000 daltons. But analysis by ion-exchange chromatography demonstrated that they do not have identical biochemical properties. The present studies suggest that biologically active factors produced by T cells stimulated with carrier protein may induce the enhancing effect on the proliferation and differentiation of hemopoietic stem cells and immune responses to the hapten-carrier conjugate.
Adherence of Recirculating T and B Lymphocytes to High Endothelium of Lymph Nodes in Vitro
Authors: Kuttner Barry J. , Woodruff Judith J.
Published: December 2022

Lymph nodes of murine animals contain segments of venules lined by high endothelial cells and it is specifically through such vessels that lymphocytes migrate from the blood into this tissue (1). Previous studies from this laboratory have shown that lymphocytes obtained from thoracic duct lymph, lymph nodes, and spleen are capable of adhering selectively to high endothelial cell venules (HEV)3 when the cells are deposited over glutaraldehyde-fixed frozen sections of syngeneic lymph nodes (2). The results suggest that surface membranes of recirculating lymphocytes possess recognition structures that mediate interaction with HEV.

Recirculating lymphocytes are a mixture of T and B cells and both populations are known to enter the nodes by crossing HEV (3–5). However, T cell recirculation from blood to lymph occurs more rapidly than that of B cells (3, 6). The basis for the difference in tempo of recirculation is not known but one possibility is that these populations differ with respect to their affinity for HEV (3).
Ir Gene Defects May Reflect a Regulatory Imbalance
Authors: Araneo Barbara A. , Yowell Robert L. , Sercarz Eli E.
Published: December 2022

A singular responsiveness to HEL was revealed in a peripheral lymphoid compartment of the genetically nonresponsive H-2b mouse. Although i.p. injection of HEL induces suppression and a lack of anti-HEL production, following footpad injection there is an early emergence in the popliteal lymph node (P-LN) of HEL-specific helper activity and plaque-forming cells. Furthermore, the early P-LN transiently expresses one of two T cell types needed for initiation of suppression. Delayed recruitment of the second required cell-type permits the induction of efficient suppression. There is only a short period during which there is concurrent representation of the two T cell subpopulations, and by mixing early and late deficient P-LN T cells, suppression could be established. The general implication of these results is that although a vigorous helper cell potential may exist in a strain nonresponsive to a multideterminant antigen, it can be obscured by a regulatory cell imbalance that results in the manifestation of a generalized Ir gene “defect.”
Human T Cell Growth Factor
Authors: Alvarez José M. , Silva Augusto , de Landazuri Manuel O.
Published: December 2022

We have investigated the conditions for the production of a T cell growth factor (TCGF) capable of maintaining the long-term growth of normal human T cells and present in the supernatants of human-stimulated peripheral blood leukocytes. T cell lectins induced TCGF release with maximal production by using PHA (1%) and lower activity with Con A (60 µg/ml). TCGF activity was also detected in the supernatants of MLC reactions, but in a smaller amount than after lectin stimulation. Furthermore, the cells activated by the MHC differences to produce TCGF, seemed to be included into those stimulated by PHA, since supernatants from a MLC reaction carried out in the presence of PHA did not show higher TCGF activity than did a pool of supernatants from the same donors individually stimulated with PHA. TCGF release was possible in serum-free media with inhibition of its production at serum concentrations higher than 2%. The kinetics of TCGF release were highly dependent on the cellular concentration of the cultures with a peak of activity that occurred early (18 hr) in high density cultures and later (60 hr) in low density cultures. Afterward, there was a progressive fall in activity that did not seem to be due to the release of suppressive factors. We also observed significant individual differences in the production of TCGF that were closely related to the individual variability in PHA-induced DNA synthesis.
Activation of Complement by Schistosoma Mansoni Schistosomula: Killing of Parasites by the Alternative Pathway and Requirement of IgG for Classical Pathway Activation
Authors: Santoro Ferrucio , Lachmann Peter J. , Capron André , Capron Monique
Published: December 2022

Living Schistosoma mansoni schistosomula incubated with normal chicken, guinea pig, human, and monkey sera were killed after 4 hr contact at 37°C. The following data indicate that this action is dependent on the activation of the alternative complement pathway (AP): a) the inactivity of RB, RD, and zymosan-treated serum against schistosomula; b) the partial activity of RD restored in FD; c) the full effect of the C4-deficient guinea pig, C2-deficient human, and the agammaglobulinemic human sera; d) the consumption of both the AP and FB after the incubation of NHS with schistosomula; e) the detection of C3d breakdown product during the contact of the C2-deficient human serum with these young parasites.

Killing by serum was decreased as the immature schistosomes developed and was completely absent against 4-day-old lung schistosomula (LS). In other experiments, it was demonstrated that schistosomula, in the presence of IgG, were able to initiate complement activation also through the classical pathway (CP). However, the CP does not appear to play a role in the schistosomulicidal activity of complement. The in vivo relevance of these observations is considered.
Subfractionation of Human Peripheral Blood Lymphocytes on the Basis of their Surface Properties by Partitioning in Two-Polymer Aqueous Phase Systems
Authors: Walter Harry , Webber Timothy J. , Michalski Joseph P. , McCombs Candace C. , Moncla Bernard J. , Krob Eugene J. , Graham Linda L.
Published: December 2022

Partitioning of cells in dextran-poly(ethylene glycol) aqueous-aqueous two-phase systems is a sensitive method for separating cells and for obtaining information on their surface properties. Highly purified lymphocytes were obtained by velocity sedimentation of human peripheral blood mononuclear cells and fractionated by countercurrent distribution (CCD, a multiple-step extraction procedure) in a charged two-polymer aqueous phase system. The lymphocytes remained viable after separation (order of 90%) and the E-rosetting cells responded (after adding back monocytes) to mitogens (PHA, Con A, PWM). Not only was the total lymphocyte population found to be highly heterogeneous (as evidenced by a broad and skewed distribution curve), but we were able to show that cells that rosetted with E, or had complement or Fc receptors were composed of additional subpopulations as well. The bulk of complement-receptor-bearing cells had the lowest partition coefficient (K), E-rosetting cells an intermediate K, and Fcreceptor-containing cells the highest K. The largest lymphocytes were among the subpopulation having the highest K and neither responded to T cell mitogens nor rosetted with E.

Our results thus demonstrate that human peripheral blood lymphocytes can be subfractionated by CCD. The fractions are differentially enriched with lymphocyte subpopulations having characteristic surface markers and functional abilities.
In Vitro Heterologous Cytotoxicity by T Effector Cells from Mice Immunized with Sindbis Virus
Authors: Peck Richard , Brown Arthur , Wust Carl J.
Published: December 2022

An in vitro correlate of cell-mediated cross-protection among α-viruses was demonstrated by cytotoxicity of Sindbis-immune spleen cells from mice to both Sindbis and Semliki Forest virus (SFV)-infected target cells. This cytotoxicity was shown to be mediated by the T cell population of the spleen and was independent of the presence of macrophages or B cells. The time when the level of the lymphocyte-mediated cytotoxicity (LMC) to SFV-infected cells was maximal coincides with the time when immunity to SFV is maximal in vivo, as reported previously, and when adoptive immunity to SFV can be transferred.

After one i.p. injection of Sindbis virus, the level of homologous LMC was higher than the level of heterologous LMC. However, following a second injection of Sindbis virus as immunogen, at a time when the mice are cross-protected to SFV, the heterologous LMC was considerably higher than homologous LMC. We propose that there is suppression of the effector T cells specific for Sindbis-infected cells after the second immunizing injection, probably by homologous antibody. In contrast, there appears to be an anamnestic cell-mediated response to SFV.