bluuebunny/crossref_metadata_2025 huggingface dataset:
MLC-derived human helper factor(s) that promote B cell differentiation: induction, functional characterization, and role of Ia antigens.
Authors: Friedman S M , Irigoyen O H , Gay D , Chess L
Published: December 2022

Utilizing a PFC assay to quantitate the polyclonal activation of human peripheral blood B lymphocytes, we have investigated the induction and functional activity of MLC-derived human helper factor(s). Our data demonstrate that highly purified responder T cells, but not B or null cells, are required for the elaboration of MLC helper factor(s) that trigger the in vitro differentiation of B lymphocytes into PFC. Helper factor can trigger B cell maturation in the absence of helper T cells, since complement- (C) mediated lysis of the small (less than 5%) fraction of T cells present in anti-F(ab)2 immunoabsorbent column purified B cell population eliminates the PWM induced, but not the helper factor-induced PFC response. Responder T cells required for helper factor production do not bear surface membrane Ia, since alpha p23,30 + C treatment of this population does not affect helper factor generation. In contrast, alpha p23,30 + C treatment of the allogeneic stimulator cell population eliminates helper factor production. Taken together, these results demonstrate that interaction between Ia-bearing stimulator cells and Ia- responder T cells is required for the production of MLC-derived helper factor. In additional experiments, we determined that alpha p23,30, in the absence of C, totally abrogates the PFC response triggered by MLC helper factors. This result suggests an important role for Ia antigens in the functional activity of preformed helper factor molecules.
In vitro growth of cytotoxic human lymphocytes. II. Use of T cell growth factor (TCGF) to clone human T cells.
Authors: Lotze M T , Strausser J L , Rosenberg S A
Published: December 2022

Soft agar and limiting dilution techniques utilizing human T cell growth factor (TCGF) have been developed to clone human lymphoid cells with high cloning efficiency. TCGF has been used for the continued growth and expansion of lymphoid populations derived from single T cells, and the cytotoxic specificity of individual clones has been repeatedly examined. An analysis of clones derived from human lymphocytes sensitized to allogeneic determinants in vitro reveals significant polymorphism in lytic recognition when tested against HLA typed targets. This pattern of reactivity remained constant over the 2 months of continuous culture. These methods should be capable of dissecting and analyzing the fine specificity of the T cell response.
The lipid A moiety of lipopolysaccharide is specifically bound to B cell subpopulations of responder and nonresponder animals.
Authors: Gregory S H , Zimmerman D H , Kern M
Published: December 2022

Employing autoradiography to detect [125I]-lipid A binding splenocytes and immunofluorescence to identify splenic B cells, it was observed that only a subpopulation of B cells bound lipid A. In contrast, non-B cells, including T cells and macrophage cells, exhibited either relatively little or no lipid A binding. LPS-responder and LPS-nonresponder substrains of mice exhibited essentially the same distribution of bound [125I]-lipid A among B cell subpopulations. Approximately 25% of the B splenocytes obtained from the LPS-responsive C3H/HeN substrain or from the LPS-nonresponsive C3H/HeJ, C57BL/10ScCR and C57BL/10ScN substrains bound [125I]-lipid A. On the other hand, 60% of the B splenocytes from both high- and low-responder mice derived from the CBA strain exhibited [125I]-lipid A binding. Taken in conjunction with the findings of other workers, these results are consistent with the possibility that the genetic defect in nonresponder mice is related to a lipid A triggering event rather than to lipid A binding.
Functional discrimination by human monocytes between their C3b receptors and their recognition units for particulate activators of the alternative complement pathway.
Authors: Czop J K , Austen K F
Published: December 2022

A trypsin-sensitive recognition unit for ingestion of particulate activators of the human alternative complement pathway is present on human monocytes and persists during 48 hr of culture in synthetic medium. Further, after inactivation by trypsin, the recognition unit for activators of the alternative pathway is fully regenerated in terms of function during the 48 hr of culture. In contrast, the C3b receptor on human monocytes is relatively trypsin resistant and is lost during 48 hr of culture, as assessed by its capacity to mediate C3b-dependent immune adherence or enhanced phagocytosis. The prior immune adherence of the monocytes to C3b-bearing particles does not alter the capacity of the monocytes to ingest a particulate activator, and the ingestion of particulate activators does not induce phagocytosis of the rosetted C3b-bearing particles. Thus, the functions linked to the recognition of C3b and of particulate activators of the alternative pathway are expressed independently by monocytes when the determinants reside on separate particles. When the determinants are expressed by the same particle, such as an activator bearing C3b, the monocytes exhibit a synergistic response through their distinct recognition units for C3b and particulate activators of the alternative pathway.
The response of human lymphocyte subpopulations to measles, mumps, and vaccinia viral antigens.
Authors: McFarland H F , Pedone C A , Mingioli E S , McFarlin D E
Published: December 2022

A proliferative assay employing virus-infected, fixed monolayers was used to examine the response of PBL and lymphocyte subpopulations to measles, mumps, and vaccinia viruses. The response obtained in this assay was shown to be virus specific. In individuals previously exposed to mumps or vaccinia viruses, a substantial proliferative response was elicited. In contrast, only a small number of individuals responded to measles virus even though they were seropositive for this virus. In the responders, the proliferation to each of the viruses was essentially limited to the T cell fraction and more specifically to the IgG Fc receptor-bearing T cell, the T gamma cell. The response was not dependent on the presence of antiviral antibody in the assay and was therefore apparently not related to the ADCC activity of the T gamma population. The failure of the T non-gamma cell to proliferate was not due to HLA restriction since a response in this cell population could not be elicited on infected autologous skin fibroblasts. The functional significance of the T gamma cell response is not established although a possible immunoregulatory role is considered.
The variable region of human immunoglobulins. I. Serologic and structural correlations of antigenic markers common to V lambda I and V lambda IV proteins (isotypic cross-reactivities).
Authors: Rivat-Peran L , Tischendorf F W , Dumitresco S M , Rivat C , Tischendorf M M , Haas H , Deutsch H F
Published: December 2022

Sixty-eight human lambda-chain sources including representatives of the five different subgroups were studied for the distribution of the serologic markers ST, 111, and VOR The variable region character of these antigenic determinants has been demonstrated for those proteins whose primary structures had been partially or completely determined previously. The lambda-chain sub-groups I and IV are readily distinguished antigenically but the specificity designated VOR is shared between them and is absent in the II, III, and V subtypes. The results of these studies are discussed with respect to the possible relationships of the structural genes controlling the synthesis of the lambda-chain subgroups, and some potential phylogenetic and functional meaning of the heterogeneities is revealed.
Suppression splenic T lymphocytes in human hepatosplenic Schistosomiasis mansoni.
Authors: Ellner J J , Olds G R , Kamel R , Osman G S , el-Kholy A , Mahmoud A A
Published: December 2022

Splenic suppressor cell activity was evaluated in 10 patients with advanced hepatosplenic Schistosomiasis mansoni undergoing elective splenectomy. We used cell mixing experiments to assess the effect of mitomycin-C-treated spleen cells on antigen and mitogen-induced 3H-thymidine incorporation of responder cells. The suppressor to responder ratio was 1.0. Spleen cells from 7 of 10 patients caused at least 20% suppression of phytohemagglutinin-induced 3H-thymidine incorporation of one or more populations of responder cells (spleen cells, autologous and allogeneic peripheral blood mononuclear cells)Responses of peripheral blood mononuclear cells to streptokinase-streptodornase and schistosome soluble egg and worm antigen preparations also were inhibited by co-cultured spleen cells. An inverse correlation was apparent between the spleen cell response to PHA and the suppressor activity of that spleen cell population (r = -0.74, p less than 0.05). Cell purification procedures showed that the active suppressor splenic cell was non-adherent and rosetted neuraminidase-treated sheep erythrocytes. This splenic suppressor T lymphocyte may modulate splenic and peripheral blood lymphocyte responses in patients with hepatosplenic schistosomiasis.
Requirements for T cells in alloantigen-induced generation of non-T cell-mediated cytotoxicity against syngeneic mouse sarcoma cells.
Authors: Paciucci P A , Macphail S , Bach F H , Zarling J M
Published: December 2022

In vitro stimulation of BALB/c spleen cells with allogeneic normal cells results in the generation of effector cells cytotoxic for syngeneic SV40 virus-induced MKSA fibrosarcoma cells. The conclusion that natural killer (NK) cells are activated that lyse the syngeneic tumor cells derives from findings that 1) treatment of the allostimulated BALB/c effector cells with anti-theta serum and complement does not ablate cytotoxicity against syngeneic MKSA tumor cells and 2) allostimulation of congenitally athymic (nu/nu) BALB/c mice results in significant cytotoxicity against MKSA tumor cells but not against allogeneic target cells. The requirement for the presence of theta-positive cells in alloantigen-induced activation of NK cells cytotoxic for syngeneic tumors was studied. Spleen cells from conventional BALB/c mice are cytotoxic for syngeneic MKSA tumor cells after stimulation with anti-theta serum-treated allogeneic cells or with allogeneic nude cells. In contrast, stimulation of BALB/c nude spleen cells with anti-theta serum-treated allogeneic cells or allogeneic nude cells fails to give rise to anti-tumor effector cells. Thus, theta-positive cells (presumably T cells) are required for alloantigen induced non-T cell-mediated lysis of syngeneic tumors.
Staphylococcus aureus Cowan I-induced immunoglobulin production in human cord blood lymphocytes.
Authors: Ruuskanen O , Pittard W B , Miller K , Pierce G , Sorensen R U , Polmar S H
Published: December 2022

Human cord blood mononuclear cells (MNC) were stimulated with antibiotic killed Staphylococcus aureus Cowan I bacteria (S. aureus) or pokeweed mitogen (PWM) and cultured for 6 days. Immunoglobulin synthesis and secretion was measured with the indirect protein A plaque-forming cell (PFC) assay. All 14 cord blood specimens stimulated with S. aureus produced PFC comparable to that measured in adult peripheral blood cultures. PWM induced only minimal responses in cord MNC whereas good responses were demonstrated in adult cell cultures. The majority of the cord blood immunoglobulin synthesizing cells produced IgM, however, significant production of IgA was also seen. These observations were confirmed by detection of intracytoplasmic immunoglobulin in plasma cells with the use of fluorescent anti-immunoglobulin antibodies.
Allotypy of rabbit immunoglobulins: a fifth allele at the a locus.
Authors: Brézin C , Cazenave P A
Published: December 2022

Studies in wild rabbits (Oryctolagus cuniculus) allowed the detection of a fifth allele (a101) at the a locus of rabbit immunoglobulins. The structures responsible for the A101 allotypic specificity have been found on both IgG and IgM. Their location is on the Fab fragment, on the H chain. None of the rabbits possessing A101 allotypic specificity possessed two known allotypic specificities of the a series. Genetic evidence by breeding studies agree with assignment of A101 to the a series and allow to designate this allotypic specificity as a101. a101 has been found in wild rabbits in different areas in France. It has no detectable cross-reactivity with the known allotypes. The genetic polymorphism of immunoglobulins is much larger in the Oryctolagus cuniculus species than the one described in the domestic form of the species.
Characterization of a human macrophage-like cell line stimulated in vitro: a model of macrophage functions.
Authors: Larrick J W , Fischer D G , Anderson S J , Koren H S
Published: December 2022

When cells of human macrophage-like cell line U937 are cultured in the presence of medium conditioned by mixed lymphocyte culture (MLC), PHA- or Con A-stimulated lymphocytes they demonstrate morphologic and functional characteristics of stimulation. The cells become larger, their surface more villous, and the cytoplasm has increased numbers of lysosomes and phagosomes. There is a marked (at least 10-fold) increase in antibody-dependent cellular cytotoxicity (ADCC) against both erythroid and tumor targets accompanied by increased expression of Fc receptors (FcR). There is also an augmentation of antibody-dependent phagocytosis. Medium conditioned by unstimulated lymphocytes, a B lymphoblastoid cell line or a fibroblast cell line produce very little stimulation of U937 cells. U937 cells gradually lose their increased ADCC capacity if they are washed free of conditioned medium (CM) but can be maintained in a stimulated state for long periods of time by culturing them in medium supplemented with PHA-CM at a concentration of 2%. Stimulation of macrophage-like cell line U937 may provide a useful model for further study of mechanisms of macrophage cytotoxicity and its modulation by products of activated lymphocytes.
In vitro cooperation of a antigen-specific T cell-derived helper factor, B cells, and adherent cells or their secretory product in a primary IgM response to chicken MHC antigens.
Authors: Shiozawa C , Longenecker M B , Diener E
Published: December 2022

The primary in vitro IgM response to the major histocompatibility (MHC) antigens expressed on chicken red blood cells (CRBC) has been shown to critically depend on the cooperation between antigen-specific helper factor from CRBC-primed thymus-derived helper (T) cells, bone marrow-derived (B) cells, and radioresistant (A) cells. A 500- to 1000-fold enrichment for immunocompetent B cells by means of a rosette technique permitted the culturing of as few as 2000 B cells that yielded on the average 500 plaque-forming cells against CRBC within 3 days of culture. Cell reconstitution experiments clearly showed that the presence of A cells can be circumvented by an A cell-derived secretory product. This is in disagreement with the hypothesis that helper factor acts as a mediator for antigen presentation on the A cell surface membrane. The spectrum of helper factor cross-reactivity with respect to certain alleles of the B locus was found comparable to that of antibody.
Evidence for abnormalities in separate lymphocyte populations in NZB mice.
Authors: Taurog J D , Smathers P A , Steinberg A D
Published: December 2022

Neonatally thymectomized, lethally irradiated NZB X DBA/2 and DBA/2 X NZB F1 mice were reconstituted with NZB or DBA/2 bone marrow cells and NZB or DBA2 thymocytes. Of the four resulting groups of recipient F1 mice, those given NZB bone marrow cells developed high serum IgM levels, irrespective of the thymocyte donor strain. In contrast, recipients of NZB thymocytes were resistant to induction of tolerance to BCG, irrespective of the bone marrow donor strain. Only recipients of NZB bone marrow cells made spontaneous antierythrocyte autoantibodies; of these, the responses of NZB thymocyte recipients were greater and more consistent than those of DBA/2 thymocyte recipients. Recipients of either NZB bone marrow cells or NZB thymocytes made antibody responses to ssDNA; the highest anti-ssDNA responses occurred in recipients of both NZB bone marrow cells and NZB thymocytes. We conclude that functional abnormalities in separate lymphocyte populations underlie different immune abnormalities in NZB mice.
Murine lymphocyte alloantigens. II. The Ly-7 locus.
Authors: Potter T A , Morgan G M , McKenzie I F
Published: December 2022

The murine Ly-7 locus was identified by the reactivity of alloantisera prepared as B6,C-H-2d x CXBG)F1 anti-CXBK. Most strains, except C57BL/6 and related strains, were Ly-7.2+. Absorption analysis demonstrated that the Ly-7 specificity was only found on lymphocytes and was absent from liver, kidney, brain, and red blood cells. Direct testing by cytotoxicity and protein A rosetting showed that Ly-7 is expressed in very low amounts on thymocytes, but is readily detectable on more mature T and B lymphocytes (including antibody-forming cells), with the greatest expression on B cells. Typing backcross mice with Ly-7.2 Ly-4.2, H-2.33 antisera showed that Ly-7 is not linked to the Ly-4 or H-2 loci. In raising the antisera by hyperimmunization, it was found that the antibody response to the Ly-7.2 specificity was influenced by an H-2-linked immune response gene.
A monoclonal antibody defining a lymphoma-associated antigen in man.
Authors: Nadler L M , Stashenko P , Hardy R , Schlossman S F
Published: December 2022

A monoclonal antibody (Ab 89) was developed against a lymphoma-associated antigen on the tumor cells of a patient (N.B.) with a B cell, poorly differentiated lymphocytic lymphoma (D-PDL). By indirect immunofluorescence, Ab 89 was shown to react only with N.B. lymphoma cells and was unreactive with normal N.B. lymphoid cells, normal fractionated peripheral blood cells, other normal lymphoid tissues, fetal tissues, and non-lymphoid malignant cells. In addition, Ab 89 was unreactive with conventional immunoglobulins, private and public HLA antigens, or Ia-like antigens. More importantly, Ab 89 was reactive with some B cell lymphoid malignancies. Of the 57 B cell lymphomas tested, it was found that Ab 89 reacted with approximately 10% of B cell D-PDL and B cell chronic lymphocytic leukemia (CLL). Of interest was the finding that N.B. serum contained a circulating antigen which could specifically block the reactivity of Ab 89. The data obtained suggests that Ab 89 defines a tumor-associated antigen shared by a unique subgroup of B cell lymphomas. The group of patients reactive with Ab 89 did not fall into any histopathologic classification system. These data support the notion that there is greater heterogeneity of B cell lymphomas than may have been previously recognized.
IgG1 and IgG2b share the Fc receptor on mouse macrophages.
Authors: Diamond B , Scharff M D
Published: December 2022

Monoclonal IgG1 anti-SRBC has been used to study the binding of monomeric and aggregated IgG1 to Fc receptors on mouse macrophages. Aggregated IgG1 was found to bind to Fc receptors on two macrophage cell lines and on primary macrophages. It competes for binding with IgG2b and not IgG2a. Like the binding of IgG2b, the binding of IgG1 is unaltered at 4 degrees C and is insensitive to trypsin or cytochalasin B. Antigen-bound IgG1, like IgG2b and IgG2a, mediates phagocytosis. Variant macrophage cell lines selected for the loss of phagocytosis through the IgG2b receptor no longer phagocytize IgG1 bearing SRBC. Monomeric IgG1 did not bind to either macrophage lines or primary macrophages. We conclude from these experiments that antigen-activated IgG1 binds to the same receptor as IgG2b.
Ly phenotype of lymphocytes producing murine migration inhibitory factor (MIF).
Authors: Kühner A L , Cantor H , David J R
Published: December 2022

Murine lymphocytes from lymph nodes or peritoneal exudates were tested after treatment with various anti-Ly sera plus complement for their ability to produce MIF in response to stimulation with either antigen or mitogen. When remaining cells in the LN and PEC were stimulated with either Con A or PPD, respectively, it was found that cells of the Lyl set were primarily responsible for MIF production by T cells. This does not rule out the possibility that, under certain circumstances, other T cell sets may produce MIF or material with similar properties after stimulation by antigen.
Alteration of apparent specificity of monoclonal (hybridoma) antibodies recognizing polymorphic histocompatibility and blood group determinants.
Authors: Mosmann T R , Gallatin M , Longenecker B M
Published: December 2022

The fine specificity of five mouse anti-chicken monoclonal antibodies was altered by changes in pH or temperature. Four of these antibodies recognized determinants of the MHC, and the fifth recognized another polymorphic erythrocyte antigen. The pH changes could alter a monoclonal antibody specificity from an apparently private determinant to an apparently public determinant. These alterations have been interpreted on the basis of the pH effect on binding affinity, relative to the threshold of the assay used. Consistent with this interpretation was the observation that bound antibodies were eluted most rapidly from a "cross-reacting" antigen, even at a pH where cross-reactions were strongest. Also, an increase in the valency of the monoclonal antibody resulted in an increase in the observed degree of cross-reaction. This was demonstrated in a highly multivalent antibody-directed rosette assay (ADRA), where the cross-reactions occurred over a wider pH range. These results have considerable importance for the use of monoclonal antibodies as monospecific reagents, especially in highly polymorphic systems such as the MHC. Also, these results suggest ways to improve the apparent specificity of particular monoclonal antibodies, e.g., by removing undesirable cross-reactions.
Feedback suppression: phenotypes of T cell subsets involved in the Ly1 T cell-induced immunoregulatory circuit.
Authors: McDougal J S , Shen F W , Cort S P , Bard J
Published: December 2022

Ly1 inducer t cells (Ly1:SI) activate resting T cells to generate potent suppressor activity. Primed Ly1:SI generated in vitro were assayed for suppression induction in cultures containing B cells and various Lyt T cell sets that had been positively and/or negatively selected using alpha Lyt sera. These experiments both reaffirm the previously reported requirement for an Ly123 T cell in suppression by Ly1:SI and implicate a third T cell subset, which is absolutely required for the full expression of Ly1:SI-induced feedback suppression. This subset of T cells has the cell surface phenotype, Ly1- Ly23+ 1J+ Qa-1-.
Human endothelial culture supernatant (HECS): a growth factor for hybridomas.
Authors: Astaldi G C , Janssen M C , Lansdorp P , Willems C , Zeijlemaker W P , Oosterhof F
Published: December 2022

Human endothelial culture supernatant (HECS) had strong growth-promotion activity for hybridoma cells: the yield of hybridomas after fusion was increased at least 2-fold over that in the presence of feeder cells, such as mouse macrophages and spleen cells. Moreover, HECS could substitute for feeder cells when hybridomas were cultured at the single-cell level, and strongly enhanced the proliferation of hybrid cells. furthermore, the presence of human endothelial cells prolonged the stability of human-mouse hybridomas, producing human immunoglobulin, hybrids known to survive poorly during culture in vitro.
Purification of immunologically functional subsets of human Ia-like antigens on a monoclonal antibody (Q5/13) immunoadsorbent.
Authors: Quaranta V , Walker L E , Pellegrino M A , Ferrone S
Published: December 2022

Serologic and immunochemical asays have shown that the monoclonal antibody Q5/13 recognizes an antigenic determinant expressed on a subset of human Ia-like antigens. Testing with a panel of HLA typed B lymphoid cells has shown that this determinant is different from those defining the serologic polymorphism of HLA-DR antigens. The monoclonal antibody Q5/13 has been used to purify subsets of human Ia-like antigens, which are immunologically functional. These reagents should facilitate the characterization of structural and functional properties of human Ia-like antigens.
Effect of dextran-S (alpha, 1-3 dextran) on the growth of plasmacytomas MOPC-104E and J558.
Authors: Bhoopalam N , Heller P , Meyerstein N , Hall L
Published: December 2022

The murine plasmacytomas MOPC-104E and J558 secrete IgM-lambda and IgA-lambda, respectively, which are antibodies to alpha, 1-3 dextran, a constituent of dextran-S (DEX-S) extracted from Leuconostoc mesenteroides. A single i.p. injection of 10 microgram DEX-S into BALB/c mice from 7 days before and up to 3 days after the implantation of 5 x 10(3) plasmacytoma cells protected the BALB/c mice from developing the tumors. Immunization with other antigens, such as Escherichia coli lipopolysaccharide, inulin (alpha, 1-6 linkage), and dextran T-10 (no known alpha, 1-3 linkages) did not protect the mice from developing the tumors. Growth of LPC-1 was not affected by DEX-S. The mechanism of this growth inhibition is unknown. It does not appear to depend solely on binding of antigen to tumor cells, and the limits of the effective time intervals between antigen and tumor injection suggest dependence on the presence of antibody to alpha-1,3 dextran.
Differences in the characteristics of inhibition of lymphocyte stimulation by 25-hydroxycholesterol and by the immunoregulatory serum lipoprotein LDL-In.
Authors: Curtiss L K , Edgington T S
Published: December 2022

Suppression of peripheral blood lymphocyte phytohemagglutinin-stimulated 3H-thymidine uptake in vitro by serum lipoprotein fractions enriched in the immunoregulatory low density lipoprotein (LDL-In) and by 25-hydroxycholesterol was compared to determine whether the biologically active constituent of LDL-In might be an oxygenated sterol. Dose titrations indicated that 25-hydroxycholesterol was 100 times more potent than LDL-In on the basis of total sterol. Both were similar in that maximal inhibitory activity was evident when they were present in the cultures for at least 24 hr before mitogen stimulation. However, the suppression of 3H-thymidine uptake by 25-hydroxycholesterol required the continuous presence of the sterol, whereas equivalent suppression by LDL-In was irreversible and did not require the presence of the lipoprotein beyond the preincubation period. 25-Hydroxycholesterol-mediated suppression of 3H-thymidine uptake was mitigated by the addition of cholesterol or mevalonic acid to the lymphocyte cultures, consistent with an effect on sterol biosynthesis, whereas, LDL-In mediated suppression was not. Finally, when chloroquine was used to inhibit lymphocyte lysosomal hydrolysis, which is required for the intracellular degradation and release of cholesterol esters from internalized low density lipoprotein, the phenotypic expression of LDL-In mediated suppression was not altered, indicating that this known pathway of regulation of cellular function by low density lipoproteins is not the primary mode of action of LDL-In. These data indicated that the mode of suppression of mitogen-stimulated thymidine uptake by serum lipoprotein fractions enriched in LDL-In differs from that produced by 25-hydroxycholesterol, and that LDL-In suppression does not appear to result from inhibition of intracellular cholesterol biosynthesis.
In vitro induction of human cell-mediated cytotoxicity directed against herpes simplex virus-infected cells: characterization of the effector lymphocyte.
Authors: Rola-Pleszczynski M
Published: December 2022

Normal human peripheral blood mononuclear leukocytes (PBML) were incubated (sensitized) in vitro for 6 days with herpes simplex virus type 1 (HSV-1)-infected cells. The sensitized PBML were then tested in a 5-hr 51Cr-release microassay against uninfected or HSV-1-infected target cells. PBML subpopulation-depletion studies revealed that the effector cells were neither B cells nor monocytes, but that their activity was found both in the E-rosetting and the non-E-rosetting lymphocyte fractions. Further separation techniques showed that the effector cells in either fraction expressed an Fc receptor for IgG. In vitro-generated, virus-specific cytotoxic activity thus appeared to be mediated both by a T gamma cell and a special null cell, suggesting possible NK cell involvement.
Characterization of cloned murine cytolytic T cell lines.
Authors: Engers H D , Collavo D , North M , von Boehmer H , Haas W , Hengartner H , Nabholz M
Published: December 2022

Murine cytolytic T lymphocytes can be kept in continuous culture apparently indefinitely by repeated passage in a concanavalin A-induced growth promoting medium. Some of these long-term cell lines maintain their cytolytic activity. Starting from three such populations, several cloned cytolytic T cell lines were derived and subsequently subcloned one or more times. Considerable variation in the levels of cytolytic activity was observed between different subclones; some initially active subclones lost activity with prolonged culture. In addition, one of the clones appeared to progressively lose the relative specificity demonstrated during the earlier passages of the parent cell line.
Antigenic determinants of influenza virus hemagglutinin. V. Antigenicity of the HA2 chain.
Authors: Brown L E , Dopheide T A , Ward C W , White D O , Jackson D C
Published: December 2022

All the polypeptide fragments obtained by cyanogen bromide cleavage of the hemagglutinin from A/Memphis/102/72 influenza virus were examined for their ability to bind to IgG raised against purified virus. Within the hemagglutinin heavy chain the only fragment displaying antigenicity is HA1CN1, which comprises the amino-terminal 168 amino acid residues. By the use of a sensitive radioimmunoassay in which the antigen is unlabeled, it was shown that the light chain is also antigenic. Inhibition studies have localized the activity to the HA2CN1 region, which comprises the carboxy-terminal 90 amino acids. The determinant on HA2 is shown to be subtype specific.
Hapten-specific T cell responses to 4-hydroxy-3-nitrophenyl acetyl.
Authors: Sunday M E , Weinberger J Z , Benacerraf B , Dorf M E
Published: December 2022

The primary anti-(4-hydroxy-3-nitrophenyl)acetyl (NP) antibody response is known to have a heteroclitic fine specificity, i.e., anti-NP antibodies bind (4-hydroxy-5-iodo-3-nitrophenyl)acetyl (NIP) with greater affinity than NP itself. Past studies of NP-specific DTH responses and NP-specific T cell-mediated suppression have demonstrated sharing of fine specificity patterns and idiotypic structure between receptors on NP-specific T cells and anti-NP antibodies. We now analyze the fine specificity of NP-specific cutaneous sensitivity (CS) reactions to NP-O-succinimide (NP-O-Su) and NIP-O-succinimide (NIP-O-Su). The specificity of these responses is shown to be controlled by genes in the Igh gene complex. Cross-reactive CS responses induced by NP-O-Su elicited by NIP-O-Su were observed in strains of mice possessing the Igh-1b allotype but not in strains bearing the Igh-1c or Igh-1j allotypes. The CS reactivity could be adoptively transferred to naive recipients, and the ability of transfer CS reactivity was T cell dependent. In contrast to the genetic requirement for I-A region homology to adoptively transfer DTH reactions, compatibility at either the H-2K, H-21, or H-2D regions was sufficient to transfer NP-specific CS reactivity to naive recipients. Furthermore, in contrast to DTH responses, cyclophosphamide pretreatment was not required to induce CS responsiveness. Thus, the specificity of NP-O-Su-induced CS responses is controlled by both H-2- and Igh-linked genes.
Polyclonal activation of murine B lymphocytes by Fe fragments. II. Replacement of T cells by a soluble helper T cell-replacing factor (TRF).
Authors: Thoman M L , Morgan E L , Weigle W O
Published: December 2022

Fc fragments of human gamma-globulin stimulate T cell-dependent polyclonal antibody responses in murine splenic B cells. The T cell signal can be delivered by a soluble T cell-replacing factor, derived by concanavalin A stimulation of spleen cells. TRF interacts directly with responding B cells and appears to provide the second, differentiative, trigger that initiates the polyclonal response. TRF is maximally active even if added at 24 hr after Fc and does not alter the response kinetics. Although macrophages are requird for the polyclonal activation of B cells in intact spleen cell cultures, they are not necessary for the delivery of the TRF signal to B cells.
The autologous mixed lymphocyte reaction in strains of mice with autoimmune disease.
Authors: Glimcher L H , Steinberg A D , House S B , Green I
Published: December 2022

We have studied the autologous mixed lymphocyte reaction (AMLR) in 3 strains of mice with autoimmune disease. T cell proliferation to autologous non-T cells occurs in young mice of these 3 strains (as it does in normal mice) but is absent or greatly reduced in older mice of strains with autoimmune disease. Reciprocal mixing experiments revealed that the defect in the AMLR of the older mice resides in the responder T cell population. Further analysis of the cells participating in the AMLR of young mice of the B/W F1 strain revealed that: 1) a Thy 1- and Ly1-positive responder cell was necessary at the start of the culture to initiate the AMLR; 2) the cells present after 5 days of culture contained very few, if any, Ly123 cells in the B/W F1 strain compared with the normal C57BL/6 strain; and 3) the stimulating cell appear to be a macrophage, and an Ia-bearing cell must be present for the reaction to occur.
An analysis of the lymphocyte content of rat lacteals.
Authors: Steer H W
Published: December 2022

A technique for the collection of lymph from the lacteals of the small intestine of the rat is described. The output of lymphocytes from an area possessing a Peyer's patch is 10 times greater than in lymph from an area lacking one, but the proportion of lymphocytes with surface immunoglobulin (sIg), surface immunoglobulin A (sIgA), and internal immunoglobulin A (iIgA) are similar in the 2 areas. A lower percentage of lymphocytes bear sIg in lymph afferent to the mesenteric lymph gland compared with that found in the thoracic duct. However, a higher proportion of these lymphocytes bearing sIg have IgA on their surface in lacteal lymph compared with thoracic duct lymph. The reasons for these differences between the lacteal lymph and thoracic duct lymph are discussed.
Conformation of Immunoglobulin M. III. Structural requirements of antigen for complement fixation by equine IgM.
Authors: Siegel R C , Cathou R E
Published: December 2022

Complexes of IgM equine anti-dansyl antibodies and different dansyl substituted carriers were tested for their ability to fix complement (C). Only dansyl92-Ficoll and dansyl12-poly-L-lysine were found to be effective. Dansyl13-bovine serum albumin, dansyl127-keyhole limpet hemocyanin, and reduced and alkylated dansyl10-ribonuclease were all ineffective. Lack of C fixation by the dansyl-ribonuclease was not due to lack of antibody-antigen complex formation, since binding at the concentrations employed for C fixation was established. However, in contrast, polymerized dansyl-ribonuclease (polydisperse, with m.w. = 74,000 to 230,000) was very effective in inducing C fixation. These results suggest that large antigen size is necessary for IgM to bind in a multivalent fashion to provide the correct conformation for C fixation. A similar conclusion had been made in earlier studies on rabbit IgM by Cunniff and Stollar. Since optimal C fixation occurred at lower antigen concentrations than maximal precipitation, it would appear that complexes in which several combining sites within a given IgM molecule may be bound to the same antigenic surface may be the most effective. The observation that the amount of C1q bound to antibody was the same in the presence and absence of antigen suggests that enhanced C fixation by antibody-antigen complexes is due to additional C component interactions such as C1r or C1s.
Natural cytotoxicity in the mouse embryo. I. Evidence for the presence of natural cytotoxic function in the yolk sac of the 10-day mouse embryo.
Authors: Dahl C A
Published: December 2022

Yolk sac cells from 10-day mouse embryos have natural cytotoxic activity directed against YAC-1 tumor targets but not against P815 tumor targets. Other embryonic tissues tested, including TG-16 embryonal carcinoma, fetal thymus, and fetal liver, do not display natural cytotoxic activity comparable to the yolk sac activity. The correlations between yolk sac natural cytotoxic function, and adult NK and promonocyte cytotoxic functions are briefly discussed.
In vivo and in vitro effects of colchicine and vinblastine on the secretory process of antibody-producing cells.
Authors: Antoine J C , Maurice M , Feldmann G , Avrameas S
Published: December 2022

The sensitivity of the secretory process of antibody-synthesizing cells to microtubule-binding drugs, colchicine and vinblastine sulfate, was studied. Rats were immunized by footpad injections of horseradish peroxidase, and the popliteal lymph nodes were removed at various times after injection. Both in vivo effects of colchicine and in vitro effects of colchicine and vinblastine were studied. Quantitative data were obtained with in vitro drug-treated cells by labeling with L-3H-leucine and by measuring the secreted and the cytoplasmic immunoglobulins. It was found that inhibition of immunoglobulin secretion was about 78% and 93% by colchicine and vinblastine, respectively. the results obtained with the latter drug were more difficult to interpret because it also inhibited the biosynthesis of total proteins, and particularly that of immunoglobulins. Immunocytochemical studies of the in vivo and in vitro drug-treated cells performed by light and electron microscopy showed that in antibody-containing cells the Golgi area was often occupied by dilated antibody-containing vesicles, probably derived from the Golgi apparatus. In a few of these cells it was observed that antibody-containing rough endoplasmic reticulum was markedly dilated. the above results demonstrate that both microtubule-binding agents, colchicine and vinblastine, are potent inhibitors of the secretory process of plasma cells and seem to indicate that a correlation may exist between ultrastructural changes and inhibition of secretion.
Isolation and characterization of lymphocyte mitogenic factor released in vivo during a cell-mediated immune reaction in the guinea pig.
Authors: Postlethwaite A E
Published: December 2022

By use of a guinea pig model of delayed hypersensitivity to horseradish peroxidase (HRPO), it has been possible to characterize the rate of release of lymphocyte mitogenic factor (MF) in vivo after i.p. challenge immune animals with antigen. MF is present in peritoneal fluid of immune guinea pigs 4 to 12 hr after i.p. challenge with HRPO, before 2 other lymphokines, lymphocyte-derived chemotactic factor for monocytes and macrophage migration-inhibitory factor, are released. The m.w. of MF generated in vivo and in vitro, as estimated by gel filtration, are similar, approximately 25,000. In vivo and in vitro MF are stable upon heating to 56 degrees C for 30 min. This observation that a mitogenic factor for lymphocytes is released early in vivo in a delayed hypersensitivity reaction gives support to the notion that its primary function in vivo may be to amplify cell-mediated immune reactions.
Anti-carbohydrate activity of T cell-reactive chicken anti-mouse immunoglobulin antibodies.
Authors: Layton J E
Published: December 2022

The specificity of chicken anti-mouse immunoglobulin F(ab')2 antibodies, which bind readily to T cells and have been claimed to detect immunoglobulin on T cells, was analyzed by indirect immunofluorescence. It ws found that only a minor proportion of the total antibody bound to T cells whereas the major fraction bound only to B cells. The T cell-reactive antibody cross-reacted with bovine IgG and therefore could be purified on this basis by affinity chromatography. T cell staining was inhibitable with nonimmunoglobulin glycoproteins as well as immunoglobulin, in contrast to staining with the B cell-specific antibody fraction, which was only inhibited by immunoglobulin. This suggested that the T cell staining was caused by anti-carbohydrate antibody. Inhibition of T cell staining was abolished by periodate oxidation of the inhibitors but not by proteolytic digestion. In addition, the antigenic determinant on the cell surface was not destroyed by autoclaving. Finally, antibody was absorbed on a mucin-Sepharose column and anti-T cell activity was found in the bound but not the unbound fraction. These results strongly suggest that the only anti-T cell activity in the chicken antibody is anti-carbohydrate antibody.
Derivation of a monoclonal antibody that detects an Ia antigen encoded by 2 complementing I-subregions.
Authors: Harris J F , Delovitch T L
Published: December 2022

A monoclonal antibody designated A303, which reacts with Ia antigens controlled by the complementation of 2 distinct I-subregion genes, is described. Complementation of both I-A and I-EC subregion gene products is necessary for the cytotoxic, direct and 125I-protein A-amplified indirect cell binding, and immunoprecipitation activities of A303. Positive prototype strains of independent origin include H-2k,p, whereas A303-negative haplotypes include H-2b,d,f,r,s,u. Seven recombinant strains, H-2ap5,as1,h4,i3,i5,t3,t4 representing intra I-region cross-over events between positive and negative haplotypes are A303 negative. Trans complementation occurs between the I-Ak allele and the I-EdCd, I-EkCk and I-EkCd alleles, respectively. Analysis of F1 heterozygotes suggests that A303-binding activity is also controlled by gene-dose effects. Thus, the activity of A303 is formally equivalent to a system of coupled complementation previously described for Ir and Is genes.
Cellular immune responses of mice to influenza virus vaccines.
Authors: Reiss C S , Schulman J L
Published: December 2022

Parenteral sensitization of mice with equivalent amounts of untreated, gradient-purified or UV-inactivated influenza A/PR/8/34 virus (PR8 virus) results in the stimulation of maximal serum antibody titers, greatest numbers of antibody-forming cells (AFC), and strong virus-specific cytotoxic T lymphocyte (CTL) activity. In contrast, inoculation of formalin-inactivated virus, which induced antibody titers of equivalent magnitude, did not elicit a measurable primary CTL response nor prime for a secondary response. However, in mice previously exposed to untreated virus, challenge with formalin-inactivated virus evoked a secondary CTL response. Immunization of unprimed mice with aggregated viral glycoproteins or detergent-disrupted virus vaccine was much less immunogenic for antibody and AFC responses and did not evoke measurable primary, secondary, or memory cytotoxic effector cells in vivo.
The glycolipid asialo GM1 as a new differentiation antigen of fetal thymocytes.
Authors: Habu S , Kasai M , Nagai Y , Tamaoki N , TAda T , Herzenberg L A , Okumura K
Published: December 2022

Antibody directed to the neutral glycolipid "asialo GM1" was found to react with the majority of thymus lymphoid cells lacking characteristic T cell markers in mice at an early embryonic stage (13 days of gestation). The proportion of these asialo GM1-positive cells (asialo GM1+ cells) decreased strikingly thereafter, contrasting with an increased fraction of lymphocytes possessing T cell surface markers such as Thy-1, Lyt-1, and Lyt-2. After about 18 gestational days, only a few asialo GM1+ cells were detected in the thymus as well as in other lymphoid organs. Double-staining analysis of the embryonic thymocytes (13 days of gestation) with anti-asialo GM1 and anti-Thy-1 demonstrated that thymocytes stained with anti-asialo GM1 did not react with anti-Thy-1, and vice versa. Morphologic examination by immunoelectronmicroscopy demonstrated that these asialo GM1+ cells were mainly composed of immature, large lymphoid cells having large nucleoli and relatively abundant cytoplasm with many polysomes. These results suggest that asialo GM1 is present on very early thymocytes and is lost as the mature murine T cell protein antigens Thy-1, Lyt-1, and Lyt-2 develop on these cells. The antibody to this glycolipid is a useful tool for studying embryonic thymic differentiation.
Receptors for IgA on rabbit lymphocytes. I. Distribution, specificity, and modulation.
Authors: Stafford H A , Fanger M W
Published: December 2022

The distribution of IgA binding lymphoid cells in the rabbit was determined by using ox erythrocytes coated with specific secretory IgA. After overnight incubation at 37 degrees C, the average percentage of IgA binding lymphocytes detected in major IgA-producing organs (Peyer's patches, 14.4%; appendix, 8.4%; and mesenteric lymph nodes, 11.3%), was generally higher than that detected in systemic lymphoid tissue. Lymphocytes bearing receptors for IgA (RFc alpha) were detected immediately after isolation only in the spleen and failed to appear after overnight incubation only in the thymus. That these receptors were distinct from receptors for IgM or IgG was demonstrated by cross-blocking studies with purified IgG, IgM, and IgA immunoglobulins. RFc alpha were sensitive to pronase digestion at 1 mg/ml and were regenerated with overnight incubation. In preliminary studies designed to evaluate modulation of this receptor, it was found that a significant increase in the percentage of cells expressing RFc alpha could be induced by antibodies specific for rabbit immunoglobulin. This information as a whole is consistent with the premise that RFc alpha-expressing lymphocytes may be involved in the regulation or expression of IgA-mediated immunity.
Thymoma production of T cell growth factor (Interleukin 2).
Authors: Farrar J J , Fuller-Farrar J , Simon P L , Hilfiker M L , Stadler B M , Farrar W L
Published: December 2022

Phorbol-12-myristate-13-acetate stimulates a subline of mouse EL-4 thymoma cells to produce, in vitro, in very high titer, T cell growth factor (Interleukin 2, IL 2). The EL-4-derived IL 2 has the same m.w. (30,000) and isoelectric point heterogeneity (pI 3.8-4.4) as the IL 2 produced by Con A-stimulated spleen cells. In addition, the thymoma-derived IL 2 exhibits the same spectrum of biologic activities as has been reported for spleen cell-derived IL 2.
Characterization of the Fc receptor for IgG on a human macrophage cell line, U937.
Authors: Anderson C L , Abraham G N
Published: December 2022

Since the U937 cell line expresses many characteristics of normal human monocytes and macrophages, we studied in detail its receptors for IgG by measuring direct binding and inhibition of binding of 16 radioiodinated human myeloma proteins representative of the 4 subclasses. As with normal monocytes, IgG1 and IgG3 bound most efficiently (17.3 and 15.7% bound), IgG4 less readily (7.1% bound), and IgG2 least readily (0.6% bound). Scatchard plots of IgG1 binding showed approximately 18,000 binding sites/cell with Ka approximately 10(8) liter/mol. IgG1 binding was inhibited equally well by IgG1 and IgG3 (50% inhibition with 0.26 +/- 0.03 and 0.26 +/- 0.09 microgram, respectively). IgG4 inhibited less readily (0.68 +/- 0.12 microgram). Three IgG2 proteins were not inhibitory (115 +/- 59) but one IgG2 myeloma inhibited well (0.89 +/- 0.47). IgG Fc fragments inhibited IgG1 binding 1000-fold more efficiently than Fab fragments, IgM, and IgA. Reciprocal inhibition experiments gave no indication of multiple receptor sites of differing specificities. In situ, the IgG1 receptor was resistant to proteases. The data suggest that the U937 Fc receptor may be a useful model of human macrophage structure and function.