bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and secretion of plasma proteins by embryonic chick hepatocytes: changing patterns during the first three days of culture.
Authors: Grieninger G , Granick S
Published: June 2004

A simple model system is described for studying synthesis of plasma proteins. The system is based on chick embryo hepatocytes in primary monolayer culture which synthesize a broad spectrum of plasma proteins and secrete them into the culture medium. The secreted proteins are stable and consist almost exclusively of plasma proteins. The cultured cells are nonproliferating hepatic parenchymal cells whose cell mass remains constant in culture. By a modification of Laurell's rocket immunoelectrophoresis, the secreted plasma proteins can be detected in nanogram amounts in 3 microliter of unconcentrated culture medium. Kinetics of secretion are obtained by sequential assay of proteins accumulating in the medium. In this system it is demonstrated that: (a) intracellular plasma protein levels are equivalent to less than 5% of the daily secretion; (b) synthesis and secretion are continuous; and (c) the overall half-time for plasma protein movement along the secretory pathway is less than 10 min. From these results, it follows that the rate at which the plasma proteins are secreted gives a valid estimate of their rate of synthesis. This feature of the culture and the sensitivity of the assay allow routine measurements of plasma protein synthesis without disruption of the cells and without the use of radioisotopes. It is shown, furthermore, that the overall rate of plasma protein synthesis in cultured hepatocytes is constant over a 3-day period and is similar to that of the intact liver. 3,000,000 cells, containing 1 mg cell protein, synthesize 0.2 mg of plasma proteins daily, amounting to one-fifth of hepatocellular protein synthesis. Under the conditions used, albumin synthesis steadily decreases with culture time whereas the synthesis of many other plasma proteins increases. The observed phenotypic changes and reorganization of plasma protein synthesis illustrate how the system may be exploited for studying the regulatory processes governing plasma protein synthesis.
Antigen requirements for induction of B-memory cells: studies with dinitrophenyl coupled to T-dependent and T-independent carriers.
Authors: Braley-Mullen H
Published: June 2004

Mice were primed with dinitrophenyl (DNP) (trinitrophenyl, TNP) coupled to thymus-independent (TI) or thymus-dependent (TD) carriers. B cells from these mice were transferred to irradiated recipients with T cells from keyhole limpet hemocyanin (KLH)-primed mice. After secondary immunization with DNP-KLH a significant DNP-specific IgG memory response was produced only by mice which received B cells which had been primed with TD antigens. TI antigens were unable to induce differentiation of B-cell precursors to IgG producing memory B cells but they did not suppress the induction of B-memory cells by TD antigens. The results indicate that TI antigens fail to activate a cell type which is required for the induction of memory B cells.
Restricted helper function of F1 leads to parent bone marrow chimeras controlled by K-end of H-2 complex.
Authors: Sprent J
Published: June 2004

F1 leads to parent bone marrow chimeras were prepared by transferring F1 hybrid marrow cells into heavily irradiated parental strain mice. When unprimed, donor-derived F1 T cells from the chimeras were activated to sheep erythrocytes (SRC) for 5 days in irradiated normal F1 mice, high IgM and IgG anti-SRC responses were observed with F1 B cells, and with B cells H-2-compatible with the strain in which the T cells were raised from stem cells. Significantly, however, responses with B cells of the opposite parental strain were either absent or very low. The restriction in T-helper function mapped to the K-end of the H-2 complex and could not be attributed to active suppression.
Hematopoietic thymocyte precursors: IV. Enrichment of the precursors and evidence for heterogeneity.
Authors: Basch R S , Kadish J L , Goldstein G
Published: June 2004

A method has been developed for the enrichment of the hematopoietic precursors of thymocytes from spleen and bone marrow cells. Up to 40-fold enrichments were obtained resulting in preparations in which as few as 10(5) cells produced prompt repopulation of the thymus of an irradiated mouse. Precursor cells from bone marrow appear to contain the enzyme terminal deoxyribonucleotidyl transferase (Tdt), an agent suggested as a potential somatic mutator. This enzyme (Tdt) was not detectable in any spleen cell preparation examined, including one in which a 40-fold enrichment of thymocyte precursors had been produced. This is the first difference reported between the splenic and bone marrow precursors of thymocytes.
Mitogenic analysis of murine B-cell heterogeneity.
Authors: Bona C , Yano A , Dimitriu A , Miller R G
Published: June 2004

The B-cell mitogens lipopolysaccharide (LPS), Nocardia water-soluble mitogen (NWSM), and dextran sulfate (DxS) react with different subpopulations of B lymphocytes. Selective in vitro killing of cells responding to either LPS or NWSM has little effect on the in vitro response to the other mitogen, although the response to DxS is reduced in both cases. If, after selective in vitro killing, cells are injected into irradiated mice for 2-3 wk before measuring their in vitro mitogen responses, the same specificity pattern is seen. Thus, one is dealing with different B-cell subpopulations rather than different stages of maturation of a single population. Treatment with various alloantisera and complement before measuring the mitogen response to LPS and NWSM shows that (a) whereas all LPS response cells carry surface Ig, a subpopulation of NWSM responsive cells does not; (b) both LPS- and NWSM-responsive cells carry I-A antigens but might not I-E or I-J antigens; (c) all LPS-responsive cells carry I-C antigens, whereas approximately 25% of NWSM responsive cells do not: (d) there is a subpopulation of NWSM-responsive cells carrying neither surface Ig nor I-C antigens and resistant to anti-theta treatment.
A study of proteases and protease-inhibitor complexes in biological fluids
Authors: Granelli-Piperno A , Reich E
Published: June 2004

We have (a) screened a variety of cell lines and body fluids for plasminogen activators and (b) studied the activity of proteases bound to α2- macroglobulin after exposing the complexes to partial degradation and/or denaturing procedures to unmask proteolytic activity. The respective results show (a) that the plasminogen activators in urine and cell culture media are generally of lower molecular weight than those in plasma; and (b) that proteases bound to α2-macroglobulin recover the ability to attack macromolecular substrates after exposure to sodium dodecyl sulfate while retaining the electrophoretic mobility of the protease inhibitor complex. This indicates that the protease and inhibitor are probably linked by covalent bonds. In contrast, other complexes formed between proteases and inhibitors of lower molecular weight (such as soybean or Kunitz inhibitors) are fully dissociated by sodium dodecyl sulfate (SDS).

The experiments described were based on a new procedure for detecting proteolytic enzyme activity in SDS-polyacrylamide gels. The method relies on solutions of nonionic detergents for extracting SDS, after which the electrophoretic gel is applied to an indicator gel consisting of a fibrin- agar mixture. The method is sensitive, permitting the detection of proteinases in less than 1 μl of fresh plasma, and it is effective for resolving small differences in molecular weight. The procedure can be quantitated and, with minor modifications appropriate to each particular system, it has been applied to a broad spectrum of serine enzymes and proenzymes, including some that function in the pathways of fibrinolysis, coagulation and kinin-generation. Other potential applications appear likely.
Mononuclear phagocytes from carrageenan-induce granulomas. Isolation, cultivation, and characterization.
Authors: Bonney R J , Gery I , Lin T Y , Meyenhofer M F , Acevedo W , Davies P
Published: June 2004

Stable cultures of mononuclear phagocytes from carrageenan-induced granulomas in mice have been established after enzymatic dispersion of these lesions. The cells can be maintained for up to 3 wk without division in serum-free media. The mononuclear phagocytes were identified by several criteria. The cells are adherent, phagocytic, contain lysosomal acid hydrolases at high specific activities, secrete lysozyme, and bind soluble aggregates of IgG. The activities of 5'-nucleotidase and leucine aminopeptidase in the cultured granuloma cells showed that they resembled macrophages from thioglycollate-stimulated mice but not unstimulated macrophages in these respects. Supernates from the cultured granuloma cells contain factor(s) which induce the proliferation of thymocytes; the release of such factors by the cells is stimulated by lipopolysaccharide.
Involvement of fusion activity of ultraviolet light-inactivated sendai virus in formation of target antigens recognized by cytotoxic T cells
Authors: Sugamura K , Shimizu K , Back FH
Published: June 2004

Mice inoculated with ultraviolet light-inactivated Sendai virus mount a cell- mediated immune response to the virus. Cytotoxic T cells specific for Sendai virus can be obtained by in vitro secondary stimulation of primed spleen cells with syngeneic stimulator cells coated with UV-inactivated Sendai virus. Neither in vivo nor in vitro stimulation alone is sufficient to generate specific cytotoxic T cells. Sharing of the H-2 haplotype between cytotoxic T cells and target cells is required for the Sendai virus-specific lysis to occur.

The fusion (F) glycoprotein of Sendai virus has been implicated in target antigen formation (20). Ethanol treatment of Sendai virus causes complete inactivation of the cell-fusion and hemolytic activities of the envelope, but does not affect the antigenicity of the F glycoprotein; furthermore, hemagglutinin and neuraminidase activities of the envelope HANA glycoprotein are also left intact after ethanol treatment. Target cells can be prepared by coating them with various numbers of UV-inactivated Sendai virus that have been treated with ethanol or, as a control, phosphate-buffered saline (PBS). The amount of virus adsorbed to target cells during the cytotoxicity reaction time using either ethanol-treated or untreated (PBS "treated") virions is essentially identical, but target cells coated with ethanol-treated Sendai virus fail to serve as targets for cytotoxic T cells. These results indicate that fusion activity of the Sendai virus envelope is essential to the formation of the target antigen and that virus adsorption to cell surfaces without fusion of the envelope with cell membranes is not sufficient to allow killing by virus-specific cytotoxic T cells.
Acquisition of murine major histocompatibility complex gene products by schistosomula of Schistosoma mansoni.
Authors: Sher A , Hall B F , Vadas M A
Published: June 2004

Schistosoma mansoni schistosomula recovered from the lungs of inbred mice were shown to possess serologically detectable alloantigens on their tegumental surfaces. Using appropriate antisera and infected congenic and recombinant mice as worm donors, gene products of the K and I subregions of the major histocompatibility complex were demonstrated among these alloantigens acquired by the parasites. In contrast, other cell surface alloantigens, such as Thy 1, Ly 1, and H-Y and the serum proteins albumin, C3 and Ig, could not be detected on the surface of lung schistosomula by means of comparable techniques. In another series of experiments, schistosomula recovered from the lungs of mice and reinjected into allogeneic recipients were shown to exchange their alloantigens during an 87-h period of examination. Similarly, lung schistosomula cocultured with allogeneic lymphocytes were shown to acquire major histocompatibility complex (MHC) coded antigens from the cells. It is possible that as acquired host molecules, MHC gene products may disguise the surface of schistosome parasites thereby rendering them insusceptible to immune attack.
In a fully H-2 incompatible chimera, T cells of donor origin can respond to minor histocompatibility antigens in association with either donor or host H-2 type.
Authors: Matzinger P , Mirkwood G
Published: June 2004

Fully H-2 incompatible radiation chimeras were prepared using BALB congenic mice. Such chimeric mice were immunized in vivo against histocompatibility antigens of the C57BL/10Sn (B10) background in association with either of the parental H-2 haplotypes, and their spleen cells subsequently boosted in vitro with the same minor antigens. Strong H-2-restricted cytotoxic activity against minor antigens was detected, and the specificity of the restriction could be to the H-2 haplotype of the donor or the host depending on the cells used for priming or boosting. Cross priming could also be demonstrated in these mice. The results show that fully allogenic radiation chimeras can produce H-2-restricted T-cell responses to minor histocompatibility (H) antigens, and are discussed in relation to contrasting results recently obtained against viral antigens.
Resistance of neoplasms to immunological destruction: role of a macrophage chemotaxis inhibitor.
Authors: Pasternack G R , Snyderman R , Pike M C , Johnson R J , Shin H S
Published: June 2004

Several tissue culture lines of 6C3HED, a murine lymphoma, were more susceptible to immunologic destruction in vivo than the highly virulent 6C3HED line maintained by serial intramuscular transplantation. The attenuated tissue culture cells were rejected by normal syngeneic recipients, but thymectomized mice were unable to reject attenuated cells. In such mice, the growth rate of attenuated cells was equivalent to the growth rate of virulent cells in normal syngeneic mice. The increased susceptibility of attenuated cells to destruction by syngeneic hosts was shown to correlate with decreased production by the tumor cells of a macrophage chemotaxis inhibitor, and not with altered antigen density. In addition, when inhibitor isolated from virulent cells was administered to mice challenged with attenuated cells, the latter cells became virulent in vivo. When attenuated and virulent cells were administered simultaneously in the same host, the attenuated cells were able to develop into progressively growing tumors. The data suggest that the successful growth of neoplastic cells in normal may require tumor cells to produce factors which subvert the ability of the host to mobilize macrophages rapidly at the tumor site.
Cellular and genetic restrictions in the immunoregulatory activity of alpha-fetoprotein. II. Alpha-fetoprotein-induced suppression of cytotoxic T lymphocyte development.
Authors: Peck A B , Murgita R A , Wigzell H
Published: June 2004

Alpha-fetoprotein (AFP), a major component of fetal and newborn sera, was shown to exert significant immunosuppressive activity on the in vitro generation of cytotoxic T lymphocytes (CTLs). This suppression proved independent of the suppressibility of the mixed leukocyte culture activation phase, since strain combinations whose proliferative responses were refractive to AFP-induced suppression also failed to develop demonstrable CTLs in the presence of AFP. Several strain combinations were also found in which normal generation of CTLs occurred in cultures containing AFP. This refractive nature correlated with the presence of nonsuppressible lymphocyte-stimulating alloantigenic systems on the stimulating cell population. These data provide the basis for proposing several possible mechanisms for AFP-induced suppression of T-cell-mediated cytotoxicity, as well as suggesting that the primary target of this suppression is the proliferating helper T cell precommited to respond towards the major histocompatibility complex-associated lymphocyte-activating determinants.
Antigenic drift in influenza A viruses. I. Selection and characterization of antigenic variants of A/PR/8/34 [HON1] influenza virus with monoclonal antibodies
Authors: Gerhard W , Webster RG
Published: June 2004

Antigenic variants of A/PR/8/34 [HON1] influenza virus were selected after a single passage of the parent virus in embryonated chicken eggs in the presence of monoclonal antibodies to this virus. The monoclonal antibodies were produced by a hybridoma and were specific for an antigenic determinant on the HA molecule of the parent virus. Seven antigenic variants were analyzed with 95 monoclonal anti-HA antibodies prepared in vitro in the splenic fragment culture system.

Three subgroups of antigenic variants were distinguished. The antigenic changes were primarily recognized by monoclonal antibodies to the strain- specific determinants of the parental hemagglutinin (HA) molecule. Monoclonal antibodies to HA determinants shared (in an identical or cross-reactive form) by parental virus and more than three heterologous viruses of the HON1 and H1N1 subtypes were unable to recognize the antigenic change on the variants. Similarly, heterogeneous antibody preparations could not differentiate between parental and variant viruses.

The results are compatible with the idea that the HA of PR8 has available a large repertoire of antigenic modifications that may result from single amino acid substitutions, and that antigenic changes can occur in the strain- specific determinants on the HA molecule in the absence of concomitant changes in the cross-reactive HA determinants. The findings suggest that antigenic drift, in order to be epidemiologically significant, probably requires a series of amino acid substitutions in, or close to, the antigenic area on the HA molecule.
Role of the H-2 complex in induction of T helper cells in vivo. I. Antigen-specific selection of donor T cells to sheep erythrocytes in irradiated mice dependent upon sharing of H-2 determinants between donor and host.
Authors: Sprent J
Published: June 2004

When purified CBA lymph node T cells were mixed with sheep erythrocytes (SRC) and filtered from blood to lymph through irradiated syngeneic mice for 1-2 days, the donor cells lost their capacity to stimulate anti-SRC responses by CBA B cells; the response to a third-party antigen (horse erythrocytes) was unaffected and active suppression was not involved. This process of specific negative selection to SRC also occurred when semiallogeneic mice were used as filtration hosts. By contrast, when allogeneic hosts were used the helper function of the donor cells was not reduced; this applied to both primed and unprimed T cells. Studied with congeneic resistant strains indicated that negative selection to SRC occurred only when the donor and host shared H-2 determinants. Studies with T cells depleted of alloreactive lymphocytes showed that negative selection to SRC in irradiated F1 hybrid mice was followed by a stage of positive selection where the donor cells gave greatly increased responses to the injected antigen. Positive selection did not occur in H-2-different mice, however, and the helper function of the donor cells remained unchanged. By these parameters it was concluded that homozygous T helper cells have no detectable capacity to recognize antigen in an H-2-different environment.
Ethylene formation by polymorphonuclear leukocytes. Role of myeloperoxidase.
Authors: Klebanoff S J , Rosen H
Published: June 2004

Ethylene formation from the thioethers, beta-methylthiopropionaldehyde (methional) and 2-keto-4-thiomethylbutyric acid by phagocytosing polymorphonuclear leukocytes (PMNs) was found to be largely dependent on myeloperoxidase (MPO). Conversion was less than 10% of normal when MPO-deficient PMNs were employed; formation by normal PMNs was inhibited by the peroxidase inhibitors, azide, and cyanide, and a model system consisting of MPO, H2O2, chloride (or bromide) and EDTA was found which shared many of the properties of the predominant PMN system. MPO-independent mechanisms of ethylene formation were also identified. Ethylene formation from methional by phagocytosing eosinophils and by H2O2 in the presence or absence of catalase was stimulated by azide. The presence of MPO-independent, azide-stimulable systems in the PMN preparations was suggested by the azide stimulation of ethylene formation from methional when MPO-deficient leukocytes were employed. Ethylene formation by dye-sensitized photooxidation was also demonstrated and evidence obtained for the involvement of singlet oxygen (1O2). These findings are discussed in relation to the participation of H2O2, hydroxyl radicals, the superoxide anion and 1O2 in the formation of ethylene by PMNs and by the MPO model system.
Isolation and characterization of IgG molecules expressing latent group b allotypes from pedigreed b4b4 rabbits.
Authors: Yarmush M L , Kindt T J
Published: June 2004

Latent group b markers were detected in sera, in IgG preparations, and on isolated L chains from rabbits bred for homozygosity at the b locus. Serologic analysis of sera from an extended family of homozygous b4 rabbits revealed the presence of latent b allotypes in 5 of 37 sera tested. Latent b5 and b9 markers were identified; none of the sera tested contained latent b6. In two instances, the level of latent b9 allotypes was sufficiently high to permit isolation and detailed serologic characterization of the immunoglobulin population bearing this allotype. The fact that latent allotypes were detected in pedigreed homozygous rabbits minimizes the possibility that lymphoid cell chimerism is involved in latent allotype expression. Furthermore, characterization of the b9 IgG population indicates that the latent allotypic determinants do not reside on a subset of molecules with dual allotypic reactivity.
An approach to the development of new drugs for African trypanosomiasis.
Authors: Meshnick S R , Blobstein S H , Grady R W , Cerami A
Published: June 2004

The inability of the bloodstream form of Trypanosoma brucei brucei to decompose hydrogen peroxide forms the basis of our attempt to develop new pharmacological agents to kill these organisms. Approximately 1-3% of the oxygen consumed by these parasites appears in the form of hydrogen peroxide. Our previous observation that free radical initiators such as heme and hematoporphyrin D proved to be trypanocidal in vitro and in vivo, respectively, prompted this investigation into the mechanism of action of this class of compounds to enhance their therapeutic efficacy. The locus of H2O2 production within the trypanosome was examined using cell-free homogenates. Experiments described herein suggest that H2O2 is formed by the alpha-glycerol phosphate dehydrogenase in an adventitious manner, and that no enzymatic means of disposing of this potentially toxic compound are present with the organisms. Naphthoquinones were found to substantially increase the rate of both oxygen consumption and H2O2 production by trypanosomal mitochondrial preparations. Presumably, the naphthoquinones are acting as coenzyme Q analogues. The addition of sublytic concentrations of both naphthoquinones and heme leads to a synergistic lysis of the organisms in vitro. Another approach to increasing the susceptibility of T. b. brucei to free radical damage involved reduction of the intracellular concentration of glutathione. This was accomplished through the use of trypanocidal arsenicals. Melarsenoxide and heme acted synergistically in vitro, an effect which was further enhanced via addition of a naphthoquinone. Moreover, hematoporphyrin D and tryparsamide were shown to have a synergistic effect in T. b. brucei-infected mice.
Ir-genes in H-2 regulate generation of anti-viral cytotoxic T cells. Mapping to K or D and dominance of unresponsiveness.
Authors: Zinkernagel R M , Althage A , Cooper S , Kreeb G , Klein P A , Sefton B , Flaherty L , Stimpfling J , Shreffler D , Klein J
Published: June 2004

H-2 dependent and virus-specific Ir genes regulate the generation of primary virus-specific K or D restricted cytotoxic T-cell responses in vivo. The following examples have been analyzed in some detail: first, Dk restricted responses to vaccinia in Sendai viruses are at least 30 times lower than the corresponding K-restricted responses irrespective of the H-2 haplotypes (k, b, d, dxs, dxq) of K and I regions; in contrast, LCMV infection generates high responses to Dk. These findings are consistent with but do not prove that this Ir gene maps to D. Second, Db restricted responses to vaccinia and Sendai viruses are high in strains possessing the Kq or KbIb, KbaIb haplotype, are very low in strains with Kk, and relatively low in mouse strains of the KdI-Ad haplotype; LCMV generates high Db restricted response in the presence of Kk. This Ir gene for the response to vaccinia and Sendai viruses maps to K since B10.BYR (KqIkdDb) is a responder and B10.A (2R) is a nonresponder (KkIkdDb). Third, virus and K or D allele specific nonresponsiveness is dominant with variable penetrance; in heterozygous mice the nonresponder Kk allele over-rides responsiveness normally found in KbDb or KqDb combinations. Fourth, when (responder X nonresponder)F1 lymphocytes are stimulated in an environment expressing vaccinia virus plus only a high responder Kb or Kq allelle and Db, response to vaccinia Db is high; in contrast when the same F1 cells are stimulated in an environment expressing the low responder allele Kk, response to vaccinia Db is low. Thus absence of Kk during immunization allows generation of high responsive Db restricted vaccinia specific cytotoxic T cells. The Dk dependent low response to vaccinia Dk can be explained by a preclusion rule or by failure of vaccinia to complex with Db; however the analysis of Kk dependent low response to vaccinia Db does not support these explanations or that self-tolerance is responsible for this Ir effect but is compatible with the interpretation that Kk vaccinia is immunodominant over Db vaccinia. These results are discussed with respect to (a) possible mechanisms of regulation by Ir genes and (b) H-2 polymorphism and HLA-disease association.
Helper-independent mink cell focus-inducing strains of Friend murine type-C virus: potential relationship to the origin of replication-defective spleen focus-forming virus.
Authors: Troxler D H , Yuan E , Linemeyer D , Ruscetti S , Scolnick E M
Published: June 2004

Recent studies have indicated that both the replication-defective spleen focus-forming virus (SFFV) in the Friend virus complex and the helper-independent mink cell focus-inducing (MCF) viruses derived from AKR-murine leukemia virus (MuLV) are env gene recombinants between ecotropic virus and xenotropic virus. In an attempt to isolate additional env gene recombinants between Friend murine leukemia virus (F-MuLV) and xenotropic virus, we have inoculated cloned ecotropic F-MuLV into newborn NIH Swiss mice and analyzed MuLV released from preleukemic and leukemic spleens of infected mice. Two helper-independent MCF strains of F-MuLV have been isolated. Like the previously described AKR-MCF viruses, the Friend MCF viruses are env gene recombinants between an ecotropic virus (F-MuLV) and a mouse xenotropic virus, as shown by host range, interference pattern, and tryptic peptide analysis of the gp70s of these MuLV. Furthermore, RNA from the Friend MCF viruses hybridizes completely to cDNAsffv, a nucleic acid probe which detects that portion of SFFV which was not derived from P-MuLV. The ability to isolate replicating MCF viruses derived from F-MuLV FURTHER strengthens the parallels between the Friend erythroleukemia system and the AKR thymic leukemia system. Finally, the potential relationship of helper-independent env gene recombinants between F-MuLV and xenotropic virus to be highly leukemogenic SFFV is discussed.
Demonstration of opsonic activity and in vivo protection against group B streptococci type III by Streptococcus pneumoniae type 14 antisera.
Authors: Fischer G W , Lowell G H , Crumrine M H , Bass J W
Published: June 2004

The present studies demonstrate that antisera directed against Streptococcus pneumoniae type 14 is opsonic for group B streptococci type III in a neutrophile-mediated bactericidal assay. Specificity was demonstrated by the observations that group B streptococci type III and S. pneumoniae type 14 adsorbed the opsonic activity of anti-S. pneumoniae type 14 antisera. Group B streptococci strain 090R (devoid of type antigens) and S. pneumoniae type 3, did not remove the opsonic activity of anti-S. pneumoniae type 14 serum. In vivo studies using a suckling rat model of neonatal group B streptococcal type III sepsis demonstrated that antisera directed against S. pneumoniae type 14 was highly protective.
In vitro studies on lymphocyte differentiation. I. Long term in vitro culture of cells giving rise to functional lymphocytes in irradiated mice.
Authors: Schrader J W , Schrader S
Published: June 2004

In vitro cultures of mouse bone marrow cells, maintained for periods up to 7 wk, were shown to contain cells able to repopulate irradiated hosts with T and B lymphocytes. The lymphocytes were fully functional and there did not appear to be any gross restriction of their receptor repertoire. The cultured cells reconstituted irradiated semiallogenic hosts without evidence of graft-versus-host disease, suggesting that culture of donor marrow might be a useful preliminary to transplantation when tissue matching is incomplete.
Suppression of the immune response in C3H/HeJ mice by protein-free lipopolysaccharides.
Authors: Haas G P , Johnson A G , Nowotny A
Published: June 2004

The experiments described herein demonstrate the plaque-forming cell response of C3H/HeJ mice can be suppressed by a Boivin type lipopolysaccharide (LPS) and a deproteinized glycolipid. Suppression was observed both in vivo and in vitro, and could be transferred to normal cells in coculture experiments. This newly discovered effect of LPS in C3H/HeJ mice indicates that the adjuvant and inhibitory action of LPS may be distinct phenomena which are under different genetic regulation. Thus, the C3H/HeJ strain provides a convenient animal model for study of immunosuppression independent of the adjuvant effect.
Protein kinase activity associated with the surface of guinea pig macrophages.
Authors: Remold-O'Donnell E
Published: June 2004

Protein kinase activity has been detected associated with the outer surface of guinea pig peritoneal macrophages. Macrophages incubated with [gamma-32P]ATP incorporated 32P-phosphate into cell-associated proteins. Inorganic phosphate did not compete, nor could inorganic [32P]phosphate substitute as the phosphate donor, demonstrating that transfer of phosphate from ATP to protein is direct and extracellular. The macrophage-associated protein kinase was also shown to phosphorylate added acceptor protein (histone) and to be tightly associated with the cell surface. Thus, a new ectoenzyme, a protein kinase, has been detected in macrophages.
Virus-replicating T cells in the immune response of mice. III. Role of vesicular stomatitis virus-replicating T cells in the antibody response.
Authors: Minato N , Katsura Y
Published: June 2004

The functional role of the T cell (Tv) which can replicate vesicular stomatitis virus (VSV) on activation by the antigen was investigated in antibody response in vitro. By the inoculation of VSV into the culture, marked augmentation of antibody response to sheep erythrocytes (SRBC) was observed in the culture of spleen cells taken more than 3 days after the immunization with SRBC, suggesting that the VSV-susceptible suppressor cells were included in these spleen cells and the activity was eliminated by the effect of VSV. Development of two distinct types of suppressor T cells was revealed in the spleen of mice after the priming with SRBC. First, nylon wool nonadherent (NAd) suppressor T cells found in the spleen cells taken 3 days after immunization, and second, nylon wool adherent (Ad) suppressor T cells found in the spleen cells taken approximately 1 wk after immunization. The activity of nylon Ad suppressor T cells was completely abolished by VSV-preinfection, whereas that of nylon NAd suppressor T cells was unaffected. It was also shown that the helper T-cell activity was not influenced by VSV-preinfection. These results provided direct evidence that nylon Ad suppressor T cell but not nylon NAd suppressor T cell nor helper T cell can actually replicate VSV after antigenic stimulation. Thus it was strongly suggested that Tv represents the nylon Ad suppressor T cells.
The cellular basis of allograft rejection in vivo. I. The cellular requirements for first-set rejection of heart grafts.
Authors: Hall B M , Dorsch S , Roser B
Published: June 2004

The nature of the cells required for first-set graft rejection in vivo was examined by using an adoptive transfer system to restore heart-graft rejection in irradiated rats. Highly purified inocula of peripheral T lymphocytes were shown to quantitatively account for the restorative ability of adoptively transferred cells. These T cells were shown to be long-lived small lymphocytes which are not recently derived from the thymus during adult life. They belong to the pool of T cells which constantly recirculate from blood to lymph as shown by their rapid appearance in the lymph of iradiated syngeneic rats after intravenous injection. Neither B lymphocytes nor antibodies in the circulation or in the graft itself are required for first-set graft rejection.
The effect of complement on the ingestion of soluble antigen-antibody complexes and IgM aggregates by mouse peritoneal macrophages.
Authors: van Snick J L , Masson P L
Published: June 2004

Complement was found to stimulate markedly the ingestion of soluble antigen-antibody complexes by mouse peritoneal macrophages. This was shown indirectly by measuring the release of degradation products when the complexes were labeled with 125I, or directly when the antigen, that was human transferrin, was labeled with 59Fe. In this case, the metal which was released from human transferrin inside the cells was not excreted, and its accumulation in the macrophages was a direct index of the uptake of immune complexes. The decay of radioactivity in macrophages after ingestion of 125I-labeled complexes was similar when they were taken up with or without complement, indicating that complement acts primarily on ingestion and not on digestion or excretion. The ingestion of complexes was morphologically confirmed using fluorescein-labeled antigen in the immune complexes. The opsonic effect of complement was also observed with IgM aggregates indicating that soluble complexes can be ingested through complement receptors without involvement of Fc-receptors, as required for particulate antigen-antibody complexes.
Two-gene control of the expression of a murine Ia antigen.
Authors: Jones P P , Murphy D B , McDevitt H O
Published: June 2004

Two dimensional polyacrylamide gel electrophoresis of Non-Idet P-40 extracts and of specific Ia immunoprecipitates from [35S]methionine-labeled mouse spleen lymphocytes has revealed that the cell surface expression of some Ia antigens appears to be controlled by two genes. One locus, which maps in the I-A subregion, is probably the structural gene for an Ia polypeptide chain. The second locus, which maps between the I-J and H-2D regions, controls whether this I-A encoded molecule (Ae) remains in the cytoplasm or is modified and expressed on the cell surface. Complementation between these two loci allowing surface expression of Ae can occur in the cis or trans chromosomal position. Both the I-A molecule and a polypeptide chain coded for by a locus in I-E are coprecipitated by anti-I-E antibodies, suggesting that these two chains are associated with each other as a multisubunit complex in the cell. Because the ability to complement I-A for Ae expression is a property only of those strains which synthesize an I-E-encoded protein, it is likely that the I-E product itself is regulating the expression of Ae. These observations suggest several mechanisms by which interaction between two I region loci can generate new cell surface molecules. As a result, they may have important implications for understanding the molecular basis of two gene control of immune responsiveness and immune suppression.
Induction of human immunoglobulin synthesis and secretion in somatic cell hybrids of mouse myeloma and human B lymphocytes from patients with agammaglobulinemia.
Authors: Schwaber J F , Rosen F S
Published: June 2004

Somatic cell hybrid clones were isolated from the fusion of RPC 5,4 mouse myeloma cells and B lymphocytes from three patients with agammaglobulinemia. One patient had X-linked agammaglobulinemia; the remaining two patients had common varied agammaglobulinemia. All three patients had B lymphocytes which fail to secrete immunoglobulin. The hybrid nature of the clones was established by examination of metaphase chromosome spreads. Most of the clones from all three patients expressed surface immunoglobulin of mouse and human parental origin. Clones from two of the patients had fewer cells with surface Ig than hybrids from normal persons, while clones from the third patient had large numbers of surface Ig fluorescent cells. Most of the clones from all three patients synthesized and secreted human and mouse immunoglobulin. As determined by sodium dodecyl sulfate acrylamide gel electrophoresis of radioactively labeled proteins, clones from each of the patients produced human gamma, alpha, and mu-heavy chains. These studies demonstrate the presence of functional structural genes coding for human immunoglobulin heavy chains in B lymphocytes of patients with agammaglobulinemia. Further, they represent induction in the somatic cell hybrids of a gene product not expressed in the parental B lymphocytes.
Alteration of clonal profile. I. Effect of sublethal irradiation on the responses to phosphorylcholine in BALB/c mice.
Authors: Kaplan D R , Quintáns J
Published: June 2004

BALB/c mice exhibit greater than 90% H8 clonal dominance in the immune response to phosphorylcholine. Adult mice exposed to 500 rads were initally unable to produce a humoral immune response to both phosphorylcholine and trinitrophenol antigens, and the direct plaque-forming cell response was slowly regained over several weeks. Clonotypic analysis wity antisera directed against the H8 idiotype showed that the H8 clone initially dominated the recovery of the response to phosphorycholine but that 60 days after the irradiation significant numbers of non-H8 clones could be detected. This same pattern could be seen in mice irradiated with 100 rads, a dose that does not completely abrogate the H8 response to phosphorylcholine. Sublethal irradiation of neonates before they had acquired responsiveness to phosphorylcholine could also eventually lead to the emergence of non-H8 idiotypes. Thus, a radiosensitive element regulates the expression of clonal dominance in anti-phosphorylcholine responses of BALB/c mice.
Antigen-specific suppressor T-cell activity in genetically restricted immune spleen cells.
Authors: Pierce C W , Kapp J A
Published: June 2004

Virgin spleen cells develop comparable primary antibody responses in vitro to syngeneic or allogeneic macrophages (Mphi) bearing the terpolymer L-glutamic acid60-L-alanine30-L-tyrosine10 (GAT), whereas immune spleen cells primed with syngeneic or allogeneic GAT-Mphi develop secondary responses preferentially when stimulated with GAT-Mphi syngeneic to the GAT-Mphi used for priming in vivo. These restrictions are mediated by products of the I-A subregion of the H-2 complex and are operative at the level of the GAT-Mphi-immune helper T-cell interactions. To investigate why these immune spleen cells fail to develop a significant antibody response to GAT-Mphi other than those used for in vivo immunization and determine the mechanism by which the restriction is maintained, spleen cells from virgin and syngeneic or allogeneic GAT-Mphi-primed mice were co-cultured in the presence of GAT-Mphi of various haplotypes. Antibody responses to GAT developed only in the presence of GAT-Mphi syngeneic to the Mphi used for in vivo priming; responses in cultures with GAT-Mphi allogeneic to the priming Mphi, whether these Mphi were syngeneic or allogeneic with respect to the responding spleen cells, were suppressed. The suppression was mediated by GAT-specific radiosensitive T cells. Thus, development of GAT-specific suppressor T cells appears to be a natural consequence of the immune response to GAT in responder as well as nonresponder mice. The implications of stimulation of genetically restricted immune helper T cells, and antigen-specific, but unrestricted, suppressor T cells after immunization with GAT-Mphi in vivo are discussed in the context of regulatory mechanisms in antibody responses.
Suppressor T-cell activity in responder x nonresponder (C57BL/10 x DBA/1)F(1) spleen cells responsive to l-glutamic acid(60)-L-alanine(30)-L-tyrosine (10)
Authors: Pierce CW , Kapp JA
Published: June 2004

The ability of spleen cells from (responder X nonresponder)F(1) mice immunized with various GAT-Mφ, GAT-MBSA, and soluble GAT to develop IgG GAT-specific PFC responses in vitro after stimulation with responder and nonresponder parental and F(1) GAT-Mφ, was investigated. F(1) spleen cells from mice immunized with F(1) GAT-Mφ or GAT-MBSA developed secondary responses to responder and nonresponder parental and F(1) GAT- Mφ, but not to unrelated third party GAT-Mφ. Spleen cells from F(1) mice immunized with either parental GAT-Mφ developed secondary responses to F(1) GAT-Mφ and only the parental GAT-Mφ used for immunization in vivo. Soluble GAT-primed F(1) spleen cells responded to F(1) and responder parental, but not nonresponder parental, GAT-Mφ. Simultaneous immunization in vivo with the various GAT-Mφ or GAT-MBSA plus soluble GAT modulated the response pattern of these F(1) spleen cells such that they developed secondary responses only to F(1) and parental responder GAT-Mφ regardless of the response pattern observed after immunization with the various GAT-Mφ or GAT-MBSA alone. These observations demonstrate the critical importance of the physical state of the GAT used for immunization in determining the subsequent response pattern of immune F(1) spleen cells to the parental and F(1) GAT-Mφ. Further, suppressor T cells, capable of inhibiting primary responses to GAT by virgin F(1) spleen cells stimulated by nonresponder parental GAT-Mφ, were demonstrated in spleens of F(1) mice immunized with soluble GAT, but not those primed with F(1) GAT-Mφ. Because responder parental mice develop both helper and suppressor T cells after immunization with GAT-Mφ, and soluble GAT preferentially stimulates suppressor T cells whereas GAT-Mφ stimulate helper T cells in nonresponder parental mice, these observations suggest that distinct subsets of T cells exist in F(1) mice which behave phenotypically as responder and nonresponder parental T cells after immunization with soluble GAT and GAT- Mφ.
T-cell lymphoma induction by radiation leukemia virus in athymic nude mice.
Authors: Ricciardi-Castagnoli P , Lieberman M , Finn O , Kaplan H S
Published: June 2004

We report the development of extrathymic lymphoblastic lymphomas in RadLV-inoculated congenitally athymic nude mice. Thus, a leukemogenic virus which appears to require the presence of a thymus for its replication in normothymic mice can infect and transform target cells in the absence of this organ in the athymic host. The cells of one of these lymphomas have been established in vitro as a permanent cell line, BALB/Nu1. This cell line as well as a lymphoma induced in NIH/Swiss nude mice exhibit several T-cell markers, including terminal deoxynucleotidyl transferase activity, Thy-1.2, and Ly-2.2, but not Ly-1.2 nor TL. Ig determinants were not detected. The characteristics of the tumor cells support the view that cells with T-cell markers may normally exist in nude mice and undergo neoplastic transformation and clonal expansion after infection with a leukemogenic virus. The alternative possibility that virus-induced differentiation of prothymocytes may lead to the expression of Thy-1.2 and Ly-2.2 antigens is also considered. BALB/Nu1 cells release large numbers of type C viral particles. The virus, designated radiation leukemia virus (RadLV)/Nu1, has RTase activity and the protein profile characteristic of murine leukemia virus (MuLV). In radioimmunoassays, it cross-reacts completely with RadLV/VL3, a virus obtained from RadLV-induced C57BL/Ka thymic lymphoma cells in culture, and slightly with a xenotropic virus (BALB:virus-2) and with AKR MuLV. On inoculation into C57BL/Ka mice it has thymotropic and leukemogenic activity. In vitro it is B-tropic, poorly fibrotropic, and has limited xenotropic activity. Thus, RadLV/Nu1 appears to be biologically and serologically similar or identical to its parent virus, RadLV.
Recessive dystrophic epidermolysis bullosa. Evidence for increased collagenase as a genetic characteristic in cell culture.
Authors: Bauer E A , Eisen A Z
Published: June 2004

Fibroblast cultures from patients with recessive dystrophic epidermolysis bullosa (RDEB) demonstrated an increased capacity to synthesize and secrete collagenase. This phenotypic trait appeared to distinguish RDEB from other genetically distinct forms of epidermolysis bullosa. The finding of increased collagenase may be a specific manifestation of these cells in that prototypic lysosomal and cytoplasmic enzymes were present in approximately normal concentrations. In addition, this trait persisted through many cell passages, suggesting that the property was genetically determined. The elevated concentrations of immunoreactive collagenase in fibroblast cultures of patients with RDEB reflected those previously observed in vivo (4) and support the concept of a pathogenetic role for the enzyme in the blistering phenomenon. In three of the cell lines, the increase in enzyme protein occurred in association with a structurally defective enzyme. The data suggest that this may be a characteristic of all RDEB cells.
The biologic significance of alloreactivity. The ontogeny of T-cell sets specific for alloantigens or modified self antigens
Authors: Burakoff SJ , Finberg R , Glimcher L , Lemonnier F , Benacerraf B , Cantor H
Published: June 2004

We have analyzed the cellular basis of T-cell reactivity against lymphocytes expressing major histocompatibility complex (MHC) products that are foreign by virtue of polymorphism (alloantigens) or because of modification by chemicals or viruses. We find that early in ontogeny, prekiller activity against both trinitrophenyl (TNP)-coupled autologous MHC products and allogeneic MHC products resides in the same (Ly123(+)) T-cell pool; later in ontogeny alloreactivity is invested in Ly23 cells which, when activated, lyse TNP-coupled autologous cells as well as appropriate allogeneic target cells. We demonstrate that stimulation of Ly123(+) T cells in vitro by autologous cells coated with chemically-inactivated Sendai virus results in the formation of Ly23(+) cytolytic T lymphocytes (CTL) that specifically lyse both virus modified autologous target cells and unmodified allogeneic target cells.

These results suggest the following model to account for the presence of large numbers of alloreactive T-cell clones in adult animals: continuous stimulation of Ly123 cells by autologous MHC antigens associated with foreign materials such as a virus results in the formation of Ly23 memory progeny carrying receptors that recognize MHC products that are foreign due to genetic polymorphism (alloantigens). In general, these studies indicate that alloaggression (as manifest by Ly23 cells in the CTL response) reflects a high degree of cross stimulation between physiologically relevant antigens, e.g., viral determinants associated with self MHC products, and biologically irrelevant allelic variants of the MHC.