bluuebunny/crossref_metadata_2025 huggingface dataset:
The relationship between surface immunoglobulin isotype and immune function of murine B lymphocytes. I. Surface immunoglobulin isotypes on primed B cells in the spleen.
Authors: Zan-Bar I , Strober S , Vitetta E S
Published: June 2004

We investigated the ability of IgM-, IgD-, and IgG-bearing cells from the spleens of (BALB/c x C57BL/Ka)F1 mice primed to dinitrophenyl-bovine serum albumin (DNP-BSA) to restore the adoptive secondary anti-BSA and anti-DNP antibody responses. A rabbit anti-mouse IgD antiserum was prepared and the specificity documented by radioimmunoprecipitation, and cell surface staining. Purified populations of IgM-, IgD-, and IgG-bearing cells were prepared by immunofluorescent staining with isotype-specific reagents, and sorting on the fluorescence activated cell sorter. Bright or dull cells were transferred to irradiated syngeneic recipients which were challenged with DNP-BSA in saline. Unfractionated spleen cells restored an adoptive secondary serum antibody response which was all IgG (2-mercaptoethanol resistant). Purified IgM- or IgD-bearing cells restored both the secondary IgM and IgG antibody response. IgG-bearing cells restored only the IgG response. In addition, the IgG-bearing cells appear to suppress the adoptive secondary IgM response, since depletion of IgG-bearing cells from transferred spleen cells results in a marked increase in the adoptive IgM response.
Mechanism of T-cell help in the immune response to soluble protein antigens II. Reconstitution of primary and secondary in vitro immune responses to dinitrophenyl-carrier conjugates by T-cell-replacing factor.
Authors: Hünig T H , Schimpl A , Wecker E
Published: June 2004

Spleen cells of dinitrophenyl keyhole limpet hemocyanin (DNPKLH) primed and boosted mice produced a nonantigen-specific helper factor upon in vitro challenge with DNPKLH. This helper factor displays all of the biological characteristics so far described for TRF produced by allogeneic or Concanavalin A stimulation of mouse spleen cells. It restores the primary anti-SRBC response in nude spleen cultures following the same kinetics of action as T-cell-replacing factor (TRF). Conversely, TRF restores the primary in vitro immune response of nude spleen cultures to DNPKLH. TRF also restores the secondary anti-hapten IgG response of T-cell-deprived spleen cell cultures derived from DNPKLH primed and boosted mice. Here the need for carrier specificity is fully overcome. The data therefore suggest that TRF, as a nonantigen-specific maturation signal, is involved in the primary and secondary immune responses to both particulate and soluble antigens.
The release of an endogenous pyrogen from guinea pig leukocytes in vitro: a new model for investigating the role of lymphocytes in fevers induced by antigen in hosts with delayed hypersensitivity.
Authors: Chao P , Francis L , Atkins E
Published: June 2004

Guinea pig periotoneal exudate (PE) cells incubated overnight in vitro with heat-killed Staphylococci released an endogenous pyrogen (EP) that could be assayed by intravenous injection in rabbits. The febrile responses were linearly related to the dosage of EP over an eightfold range. PE cells derived from guinea pigs with delayed hypersensitivity (DH) to bovine gamma globulin (BGG), also released EP when incubated with antigen in vitro. This reaction was specific and did not occur withe PE cells from normal or complete Freund's adjuvant-sensitized guinea pigs. Studies indicated that monos and/or polymorphonuclear leukocytes rather than lymphocytes were the source of EP. However, when incubated with BGG and sufficient dosages of BGG-sensitized lymphocytes, normal PE cells released EP over a 42 h period. These results suggest that antigen stimulates specifically sensitized lymphocytes to release an agent (perhaps a lymphokine) that activates phagocytic cells to release EP. This model offers unique advantages for investigating in vitro the role of the lymphocyte in antigen-induced fever in DH as well as the relationship of this lymphocyte-induced activity to other known biologic activities mediated by antigen stimulated lymphocytes.
Production of the second component of complement by human monocytes: stimulation by antigen-activated lymphocytes or lymphokines.
Authors: Littman B H , Ruddy S
Published: June 2004

Human peripheral blood mononuclear cells cultured in the presence of antigen produced hemolytically active second complement component earlier and in larger amounts than did control cultures of the same cells without antigen. The increased amount of C2 in culture supernates came primarily from the adherent cell population and was due to increased synthesis as demonstrated by inhibition with 10(-4) M cycloheximide. Purified adherent monocytes produced more C2 when exposed to lymphokine-rich supernates from antigen-stimulated lymphocytes than when exposed to control supernates from unstimulated lymphocyte cultures. The increased synthesis of C2, which appeared to be mediated by a lymphokine, was partially inhibited specifically by 0.025 M alpha-L(-) fucose, a sugar which has previously been shown in inhibit the response of macrophages to migration inhibitory factor.
Association and dissociation of aggregated IgG from rat peritoneal macrophages.
Authors: Knutson D W , Kijlstra A , Van Es L A
Published: June 2004

Stable aggregated IgG (A-IgG) of various sizes, having high biological activity, were incubated at 4 degree C with adhering peritoneal macrophages from normal rats and the kinetics of A-IgG binding to the cell surface were studied. Equilibrium constants were high (2.8-11.7 X 10(8) M-1) and varied as a function of aggregate size. The maximum number of A-IgG bound per cell varied from 230,000 for A-IgG9 to 90,000 for A-IgG74. Binding was 50% inhibited by near physiological concentrations of monomeric IgC. These data suggest that A-IgG are bound at multiple sites by attachment of Fc frgments to Fc receptors present on the macrophage surface with larger A-IgG being more avidly bound. Dissociation was slower for larger A-IgG while no clear trend was seen relating associating rates and aggregate size. Thus, differences in the avidity of binding of A-IgG are due primarily to slower dissociation of larger A-IgG. Dissociationissociation of A-IgG was slower from cells exposed initially to higher doses of A-IgG and dissociation did not follow simple first order kinetics. Thus, the avidity of binding appears to be heterogeneous in a population of similar sized A-IgG. As expected, association was dose-dependent, more rapid than dissociation, and followed pseudo first order kinetics. Based on all of the above data, it is proposed that binding of A-IgG proceeds in two steps. First, A-IgG are loosely bound to perhaps a single Fc receptor. Then, depending upon the availability and mobility of Fc receptors, additional Fc fragments are attached and the A-IgG becomes more firmly attached. Thus binding is slow, but once attached A-IgG are avidly held.
Transfer of experimental allergic encephalomyelitis in Lewis rats using supernates of incubated sensitized lymph node cells.
Authors: Whitacre C C , Paterson P Y
Published: June 2004

Supernates derived from incubated lymph node cells of Lewis rats sensitized to guinea pig spinal cord-Freund's adjuvant transfer experimental allergic encephalomyelitis (EAE) to syngeneic recipients. EAE supernatant transfer activity (EAE-STA) is not demonstrable in supernates derived from LNC of control donors not sensitized to nervous tissue. After addition of brain antigen to active supernates, EAE-STA is not longer demonstrable.
Purification and properties of M protein extracted from group A streptococci with pepsin: covalent structure of the amino terminal region of type 24 M antigen
Authors: Beachey EH , Stollerman GH , Chiang EY , Chiang TM , Seyer JM , Kang AH
Published: June 2004

M protein was extracted from type 24, group A streptococci with pepsin at pH 5.8 and was further purified by ammonium sulfate precipitation, ribonuclease digestion, ion-exchange chromatography, and isoelectric focusing. The purified pepsin extract of M (pep M) protein was shown to be free of nontype-specific immunoreactivity in (a) complement fixation tests with heterologous M antiserum, (b) skin tests in normal adult guinea pigs, and (c) passive hemagglutination tests for the presence of lipoteichoic acid sensitizing or antigenic activity. The pep M24 was highly immunogenic; two of three rabbits developed opsonic antibody titers of 1:256 and the third a titer of 1:32 6 wk after a single injection of 100-pg doses of pep M24 emulsified in complete Freund's adjuvant. The antisera lacked nontype-specific antibodies and produced single precipitin lines in agar gel diffusion tests against crude HC1 extracts of the homologous M protein. Thus, the type-specific antigenic determinant(s) of type 24 M protein appears to be separable from immunotoxic, cross-reactive antigens without loss of immunogenicity in rabbits.

The mobility of pep M24 upon electrophoresis in 10 percent sodium dodecyl sulfate pelyacrylamide gel was consistent with an average mol wt of 33,500 daltons. Amino acid analysis demonstrated a predominance of alanine, followed by glutamic acid, lysine, leucine, and aspartic acid. Pep M24 contained an estimated six to seven methionine residues and approximately ten phenylalanine residues per molecule. No other aromatic amino acids were detected. Automatic Edman degradation of pep M24 yielded the sequence of the first 29 amino acids (the amino terminal amino acid being valine) of the amino terminal region of the molecule. The detection of only one new amino acid at each step of Edman degradation confirmed the homogeneity of the purified pep M24.
Tissue culture studies in Hodgkin's disease morphologic, cytogenic, cell surface, and enzymatic properties of cultures derived from splenic tumors
Authors: Long JC , Zamecnik PC , Aisenberg AC , Atkins L
Published: June 2004

Monolayer and suspension cell cultures prepared from Hodgkin's disease tumors in the spleen were examined microscopically and by cytogenetics, tested for lymphocyte and monocyte cell surface properties, and assayed for enzymes by histochemical and spectrophotometric techniques. Hodgkin's disease monolayer cultures were composed of rapidly proliferating round and polygonal cells that were capable of propagation in vitro for an indefinite period of time. Abnormal aneuploid chromosomes were found in short-term Hodgkin's disease monolayers that had been passaged 16-20 times, and in established cell lines carried in culture longer than 3 yr and passaged more than 200 times. Cells fromHodgkin's disease monolayers contained lysozyme (muramidase), fluoride-resistant alpha naphthol acetate esterase, acid and alkaline phosphatase, and chymotrypsin-like activity. The monolayers did not exhibit specific cell surface markers or phagocytosis. Suspension cultures derived from Hodgkin's disease monolayers were composed of cells with aneuploid karyotypes and similar enzymes. The Hodgkin's disease suspension culture cells had surface receptors for complement and IgGFc, lacked surface or cytoplasmic immunoglobulin, and did not form Erosettes, react with an antithymocyte serum, nor exhibit phagocytosis. Normal monolayer culture cells, derived from adult spleen and human fetal spleen and thymus, were composed of spindle cells with a diploid number of chromosomes that could be carried for only a finite period of time in vitro. Normal cultured cells contained similar esterases and phosphatases, but were devoid of lysozyme and chymotrypsin-like activity.

The morphologic, cytogenetic, cell surface, and enzymatic findings indicate that our Hodgkin's disease monolayer and suspension cultures are composed of cells with many properties suggesting an origin from monocytes (macrophages) rather than lymphocytes or fibroblasts. The presence of aneuploid karyotypes is consistent with a neoplastic origin and derivation from a malignant cell of Hodgkin's disease.
Suppression of IgE antibody production in SJL mice. III. Characterization of a suppressor substance extracted from normal SJL spleen cells.
Authors: Watanabe N , Ovary Z
Published: June 2004

SJL mice were immunized with 1 microng dinitrophenylated keyhole limpet hemocyanin in 1 mg Al(OH)3. The mice were infected 21 days later with 750 third stage larvae of Nippostrongylus brasiliensis. On day 35, 14 days after infection, they were injected with 1 microng DNP-N, brasiliensis extract (Nb) in 1 mg Al(OH)3. In order to obtain high titer and persistent anti-DNP IgE antibody the mice were irradiated (540 R) 1 day after injection of DNP-Nb. Suppression of anti-DNP IgE antibody production was induced by spleen cells from normal SJL mice. Suppression of IgE antibody response is also obtained by an extract from normal SJL spleen cells. The suppressor substance from normal SJL spleen cell extract is a heat-labile protein, and is not absorbed by anti-mouse immunoglobulin. The mol wt of this substance is larger than 300,000 daltons as determined by gel filtration on Sephadex G-200, but after ultracentifugation, the supernate still has suppressive activity on IgE antibody production.
Frequencies of mitogen-reactive B cells in the mouse. II. Frequencies of B cells producing antibodies which lyse sheep or horse erythrocytes, and trinitrophenylated or nitrodophenylated sheep erythrocytes
Authors: Andersson J , Coutinho A , Melchers F
Published: June 2004

The B-cell mitogens LPS and lipoprotein stimulate 20-35 percent of all B cells in the spleen of 6- to 8-wk old C3H/Tif mice, as determined by limiting dilution analysis of precursors. Each reactive cell grows to a clone of IgM-secreting PFC, enumerated in a hemolytic plaque assay detecting all IgM secreting cells, regardless of v-region specificity. We have used these mitogens to reveal the total repertoire of Ig specificities produced by these mitogen-reactive B cells. We have determined in plaque assays with six different target erythrocytes the number of spleen cells limiting to one the number of mitogen-reactive B cells detected as specific IgM-secreting clones in each of these plaque assays. By this method, the absolute frequencies of precursor B cells with defined v-gene specificities could be calculated, for at least, one third of all B cells.

The frequencies of specific IgM-plaque-forming B-cell clones within the total pool of mitogen-reactive B cells was 1 in 10 for NIP(12),-SRC, 1 in 50 for TNP(12)- SRC, 1 in 100 for NIP(1)-SRC, 1 in 160 for TNP(3)- SRC, 1 in 500 for HRC, and 1 in 1,000 for SRC. These frequencies were the same in the LPS- and in the lipoprotein-reactive B-cell population for TNP(30)- SRC and SRC.
Immunity in taeniasis-cysticercosis I. Vaccination against Taenia taeniaeformis in rats using purified antigen.
Authors: Kwa B H , Liew F Y
Published: June 2004

Artificial immunization of rats against Taenia taeniaeformis was studied using somatic antigen (Som-Ag) and excretory-secretory antigen (ES-Ag). It was found that both Som-Ag and ES-Ag stimulated immediate-type hypersensitivity and delayed-type hypersensitivity reactions of similar levels. Antibody levels rose from the 2nd wk and peaked around the 6th and 7th wk. Both IgM and IgG were detectable from the 2nd wk onwards, with IgG at a considerably higher level compared to IgM. It terms of protection, 90-100% reduction in cyst counts were detected if the rats were challenged 10 days or more after immunization. In all cases, no significant difference was observed between immunization with either Som-Ag or ES-Ag were purified and characterized using Sephadex G-200 chromatography, double immunodiffusion, and disk acrylamide gel electrophoresis. A purified antigen (mol wt, 140,000 daltons) was obtained, and highly significant protection against infection resulted with injections of 50, 10, or 1 mug doses of this antigen with complete Freund's adjuvant.
Lectin-driven maturation of cytotoxic effector cells: the nature of effector memory.
Authors: Chakravarty A K , Clark W R
Published: June 2004

In an attempt to define further the activation of effector T-cell function with concanavalin A (Con A), we examined the ability of Con A to generate effector memory in mouse lymph node cells in vitro. In the course of these studies, it became necessary to define parameters by which memory could be defined. These parameters include length of time of exposure to signal required to generate full cytotoxic function; time of onset and kinetics of blast cell formation; requirement for DNA synthesis; sensitivity to the drug 5'-bromodeoxyuridine; and kinetics of the cytotoxic response to alloantigen. By these criteria, mouse lymph node cells exposed 12 days previously to Con A behave qualitatively differently from unprimed mouse lymphocytes. We found that the time of onset and kinetics of DNA synthesis could not be used to distinguish primary and secondary cytotoxic responses. We propose that the parameters defined in these stidues can be applied generally in determining whether a given cytotoxic response involves primed (memory) or unprimed cells.
Immunosuppressive factor(s) specific for L-glutamic acid(50)-L- tyrosine(50) (GT). II. Presence of I-J determinants on the GT-suppressive factor
Authors: Theze J , Waltenbaugh C , Dorf ME , Benacerraf B
Published: June 2004

The responses to the synthetic antigens, L-glutamic acid(60)-L- alanine(30)-L-tyrosine(10) (GAT) and L-glutamic acid(50)-L-tyrosine(50) (GT) are controlled by genes in the I region of the mouse H-2 complex (1-3). Preimmunization of the mice bearing the H-2(p,q,s) nonresponder haplotypes with GAT stimulates the development of suppressor T cells that inhibit in vivo or in vitro antibody responses to GAT complexed to the immunogenic carrier, methylated bovine serum albumin (GAT-MBSA) (4). The copolymer GT is not immunogenic in any inbred mouse strain tested, and has a suppressive effect on the antibody responses to GT-MBSA in mouse strains bearing the H-2(d,f,k,s) haplotypes; suppressor T cells have been demonstrated to be responsible for specific GT suppression (3).

We have obtained specific suppressive extracts from thymus and spleen cells of GAT-or GT-primed suppressor strains (5,6). The specific suppressive T-cell factors in the active extracts have been characterized (6,7) and appear similar to the carrier-specific suppressor factor described by Tada and Taniguchi (8). These products belong to a family of newly identified molecules coded for by the I region of the H-2 complex with affinity for antigen and helper (9,10) or suppressive (5-8) regulatory activity on the immune response.

Recently, Tada et al. have reported that the keyhole limpet hemocyanin (KLH)-specific suppressor factor is coded for by the I-J subregion of the H-2 complex (11). We now demonstrate also that a GT-specific suppressor factor extracted from the spleens and thymuses of B10.BR (H-2(k)) mice bears determinants controlled by the I-J subregion of the H-2 complex.
Induction of immunological tolerance requires that the B cells can respond to the polyclonal B-cell-activating properties of the thymus-independent antigens.
Authors: Fernandez C , Möller G
Published: June 2004

Mice were rendered specifically tolerant to the fluorescein isothiocyanatedextran (FITC) epitope by injection of FITC-dextran B512. Their spleen cells were removed at various times and cultivated in vitro with different polyclonal B-cell activators, such as lipopolysaccharide (LPS), purified protein derivative of tuberculin, and native dextran. LPS caused the appearance of high affinity anti-FITC plaque-forming cells to an equal extent with cells from untreated and tolerant animals, whereas native dextran failed to activate cells from tolerant mice, although it was a potent activator of normal cells. It was concluded that tolerance induction only affects those B cells that could respond to the polyclonal B-cell-activating properties of the tolerogen, but not other B cells having an identical set of Ig receptors directed against the tolerogen.
Regulatory functions of hapten-reactive helper and suppressor T lymphocytes. I. Detection and characterization of hapten-reactive suppressor T-cell activity in mice immunized with hapten-isologous protein conjugate
Authors: Yamamoto H , Hamaoka T , Yoshizawa M , Kuroki M , Kitagawa M
Published: June 2004

Helper and suppressor T-cell activities were detected simultaneously in the spleen cells of mice immunized with para-azobenzoate (PAB)-mouse gammaglobulin (MGG). Dinitrophenyl (DNP)-specific B cells were raised by immunization with DNP-keyhole limpet hemocyanin (KLH) and used as the indicator B-cell population. The helper and suppressor T-cell activities were determined after adoptively transferring spleen cells from PAB-MGG- primed donors and DNP-KLH-primed donors into X-irradiated recipients. Stimulation of these recipients with DNP-MGG-PAB detected helper T-cell activity, which was measured in terms of increased anti-DNP antibody responses of DNP-KLH-primed cells over these responses in the presence of unprimed cells. On the other hand, when DNP-KLH-primed cells were stimulated with DNP-KLH-PAB in the presence of PAB-MGG-primed cells, anti-DNP antibody responses were substantially lower than in unprimed normal cells.

This suppressor cell population was (a) hapten-reactive, (b) present in B-cell-depleted spleen cells, (c) Thy-1 positive, (d) detectable earlier than the helper T-cell activities after priming (e) more radiosensitive than helper cells, and (f) found in the spleen but not the lymph nodes in contrast to helper T cells. These data indicate that these suppressor T cells are distinct from the helper T cells. PAB-reactive T cells clearly suppressed the antibody response by inhibiting KLH-reactive helper T-cell functions. The hapten-reactive T-lymphocyte system described here should be useful for analyzing and manipulating the immune response and for studying regulatory interactions of helper and suppressor T cells in the induction of antibody responses.
Direct visualization of T lymphocytes bearing Ia antigens controlled by the I-J subregion
Authors: Parish CR , McKenzie IFC
Published: June 2004

Previous studies have demonstrated that I-J-subregion-controlled Ia antigens are only expressed on a small subpopulation of peripheral T lymphocytes which includes the suppressor T cells of antibody responses (6). This subpopulation of T cells cannot be detected by conventional dye-exclusion cytotoxicity tests. A sensitive rosetting procedure therefore was developed for detecting the binding of anti-Ia antibodies to T lymphocytes. This assay system, unlike the complement lysis technique, has a low background and since it represents a direct binding assay could detect noncomplement-fixing antibodies in the antisera.

Anti-Ia sera were absorbed with B cells and using the rosetting procedure in genetic mapping studies the remaining antibodies were found to be directed against I-J-subregion-controlled determinants. These determinants were shown to be highly haplotype specific for H-2(k) and H-2(s) and appeared to be exclusively expressed on Ly-l.l(-), Ly2.1(+), T lymphocytes, at least some of which were suppressor T cells. Lymphoid organs differed in their content of anti-I-J-reactive cells, the hierarchy being spleen, lymph node more than thymus, bone marrow. In contrast, on a T-cell basis, a high proportion (35 percent) of the T cells in bone marrow reacted with anti-I-J antibodies, a substantial proportion (13 percent) of T cells from spleen were reactive, whereas the lymph node and thymus T-cell populations contained only a small proportion of positive cells (1-4 percent).
The generation of killer cells to trinitrophenyl-modified allogeneic targets by lymphocyte populations negatively selected to strong alloantigens.
Authors: Wilson D B , Lindahl K F , Wilson D H , Sprent J
Published: June 2004

Negatively selected mouse and rat lymphocyte populations, specifically deprived of alloreactivity to a particular major histocompatibility complex (MHC) haplotype, are nevertheless fully capable of responding to trinitrophenyl (TNP)-modified allogeneic stimulator cells and developing cytotoxic T-lymphocyte activity to TNP-altered allogeneic target cells. As for syngeneic systems, lytic expression of those responder killer cells also requires MHC identity between the target and stimulator cell populations. Such a finding argues strongly against two variations of the dual recognition hypothesis: like-like interactions and adaptive differentiation. Instead, these data favor either the altered self model or a third variation of the dual receptor model, where one of the relevent receptors is specific for the modifying antigen and the second is a low affinity receptor unable to be triggered in the absence of a modifying antigen.
A suppressor T cell in the human mixed lymphocyte reaction.
Authors: McMichael A J , Sasazuki T
Published: June 2004

Lymphocytes from an HLA-B7 DW2 homozygous multiparous woman, J.H., failed to respond in the mixed lymphocyte reaction to lymphocytes from her DW1 homozygous husband, W.H., and certain other homozygous typing cells. J.H. lymphocytes could suppress the response of HLA matched responders to W.H. This effect was shown to be radiosensitive and due to a T cell. The suppressor cell showed antigen specificity.
Antigenic modulation of Friend virus erythroleukemic cells in vitro by serum from mice with dormant erythroleukemia.
Authors: Genovesi E V , Marx P A , Wheelock E F
Published: June 2004

Friend leukemia virus (FLV) erythroleukemic cells cultured in medium containing FLV-immune serum from dormant FLV-infected mice undergo modulation of FLV cell surface antigens. Modulation was determined by an increased resistance to FLV antibody-mediated complement-dependent lysis and was associated temporally with the capping of FLV-immune complexes at the cell surface. Modulated cells regained their susceptibility to FLV antibody-mediated complement-dependent lysis when transferred to medium containing normal mouse serum. After 48 h of culture in FLV-immune serum, 26% of the FLV erythroleukemic cells were devoid of FLV cell surface antigens as demonstrated by immunofluoresence. Antigenic modulation occurred to a greater extent in cells maintained in logarithmic growth than in cells in GO or resting phase. FLV-antigenic modulation is discussed as a possible mechanism by which antibody induces and maintains FLV-transformed cells in a dormant state.
The guinea pig I region. I. A structural and genetic analysis
Authors: Schwartz BD , Kask AM , Paul WE , Geczy AF , Shevach EM
Published: June 2004

The Ia antigens of the guinea pig have been shown to play a central role in the regulation of the immune response. We have previously partially characterized the chemical structure of these antigens. In this communication, we further characterize the structure of the five Ia antigens already described, as well as two new Ia antigens. Evidence is presented which shows that these seven Ia antigens can be organized into three distinct groups, each with a characteristic structure. The Ia.2 determinant of strain 2 and the Ia.3 and Ia.5 determinants of strain 13 animals are found on molecules composed of a 25,000 dalton chain and a 33,000 dalton chain in noncovalent association, or else are individually expressed on nonlinked 33,000 and 25,000 dalton molecules. The Ia.4 and Ia.5 determinants of strain 2 and the Ia.7 determinant of strain 13 are borne on 58,000 dalton molecules in which two chains are linked by disulfide bonds. The Ia.1 and Ia.6 determinants of strain 13 are found on a molecule of 26,000-27,000 daltons. Ia.6 of strain 2 has yet to be definitively assigned. Furthermore, in strain 13 animals the Ia.3 and Ia.5 determinants are borne on the same molecule, as are the Ia.1 and Ia.6 determinants. In strain 2 animals, the Ia.4 and Ia.5 determinants are found on the same molecule. On the basis of chemical structure, we have divided the guinea pig I region into three subregions. The accompanying paper presents evidence of associations between particular Ia genes and Ir genes.
Immunostimulators induce granulocyte/macrophage colony-stimulating activity and block proliferation in a monocyte tumor cell line.
Authors: Ralph P , Broxmeyer H E , Nakoinz I
Published: June 2004

Monocyte tumor cell line PU5-1.8 does not normally produce colony-stimulating activity (CSA) required by granulocyte and macrophage progenitors to proliferate and mature in agar. However, CSA is induced in the culture line by as little as 10 ng/ml endotoxic lipopolysaccharide (LPS), with maximum CSA production and release to the medium between 2 and 3 days of incubation. Derived lipid A, but not alkali-treated LPS, is also active. Induction requires RNA and protein synthesis, but is not blocked by mitomycin C or Colcemid. Other inducers of CSA include Mycobacterium Bacillus Calmette-Guérin, tuberculin protein preparation purified protein derivative, zymosan, and phorbol myristate. All inducing agents are specific inhibitors of the monocyte tumor cell proliferation in vitro. Latex beads, another macrophage-activating agent, are rapidly phagocytosed by PU5-1.8 cells, but neither inhibit growth nor induce CSA.
Separation of helper and suppressor T lymphocytes. II. Ly phenotypes and lack of DNA synthesis requirement for the generation of concanavalin A helper and suppressor cells.
Authors: Tse H Y , Dutton R W
Published: June 2004

Using a Ficoll velocity sedimentation gradient, we have been able to fractionate concanavalin A (Con A)-induced helper and suppressor cells into separate pools. Cells activated by Con A to mediate helper activity are Ly1+, do not require DNA synthesis for induction, and remain as small cells after activation. Suppressor cells are Ly23+, are found in the blast cell fraction and their induction is not inhibitable by prior treatment with mitomycin C or irradiation, both of which inhibit DNA synthesis. The implications of such findings are discussed.
Cell-mediated mitogenic response induced by leukoagglutinin and Lens culinaris lectin in mouse lymphocytes.
Authors: Ozato K , Cebra J , Ebert J D
Published: June 2004

The proliferative response of mouse lymphocytes to syngeneic cellular stimulation upon membrane modification with lectins was studied. Brief pretreatment of stimulator cells (mitomycin-C-treated spleen cells) followed by mixed culture with syngeneic cortisone-resistant thymocytes resulted in a significant proliferative response in the thymocytes. This effect was not due to a soluble mediator and was similar to the mitogenic response after Con A-induced membrane modification reported previously. Because of its general characteristics, we refer to this response as cell-mediated mitogenic response (CMMR). Cell contact between stimulator and responder cells was necessary but not sufficient for the induction of the response. The lectins that generated CMMR were T-cell mitogens. CMMR was generated in all the syngeneic combinations tested and even in allogeneic combinations. No detectable cytotoxic activity towards syngeneic targets cells was produced after CMMR. Moreover, CMMR in allogeneic combinations led to the suppression of the generation of specific cytotoxic lymphocytes. Population analysis with antibodies against T or B cells, nylon wool fractionation of stimulator cells, and tests with peritoneal macrophages and with spleen cells from athymic mice revealed that CMMR depends predominantly on the interaction between responder T cells and stimulator Ig-positive lymphocytes.
Isolated hapten-binding receptors of sensitized lymphocytes. II. Receptors from nylon wool-enriched rabbit T lymphocytes lack serological determinants of immunoglobulin constant domains but carry the A locus allotypic markers.
Authors: Krawinkel U , Cramer M , Mage R G , Kelus A S , Rajewsky K
Published: June 2004

Hapten-binding receptor material was isolated from sensitized rabbit lymphocytes by a method described previously for murine receptor material. The material was separated into a fraction expressing immunoglobulin determinants (anti-Ig+ fraction) and a fraction lacking known class and type-specific determinants of Ig constant domains (anti-Ig- fraction). We present evidence in support of the notion that--in analogy to the mouse system--the anti-Ig+ fraction is B-cell-derived, whereas the anti-Ig- fraction originates from T lymphocytes. Receptors of the anti-Ig- phenotype are found to express a locus allotypic determinants and, thus, appear to carry variable portions of immunoglobulin heavy chains.
The ingestion and digestion of human lactoferrin by mouse peritoneal macrophages and the transfer of its iron into ferritin.
Authors: van Snick J L , Markowetz B , Masson P L
Published: June 2004

Human lactoferrin (Lf) labeled with 125I and/or 59Fe was found to be ingested in vitro by mouse peritoneal macrophages (MPM). The uptake measured after 15 h incubation reached a saturation point at a concentration of 200 microgram/ml in the culture medium, whatever was the iron content of Lf. In such conditions, the uptake of transferrin (Tf) used as a control was 10 times lower. At a concentration of 80 microgram/ml in the medium, one cell picked up about 0.7 X 10(6) molecules of Lf per hour, and 0.13 X 10(6) molecules of Tf per hour. Iron-saturated Lf disappeared from MPM with a half life of 14.5 h, whereas the halflife of iron-free Lf was 4.2 h. Concomitant with the intracellular digestion of Lf, the iron was transmitted to ferritin. These data provide additional support for the hypothesis that Lf plays a key role in iron turnover, especially at the level of the reticuloendothelial system where iron is recovered from the catabolism of erythrocytes.
Ontogeny of cell-mediated immunity. I. Early development of alloantigen-specific cytotoxic T-cell precursors in postnatal mice.
Authors: Pilarski L M
Published: June 2004

Cytotoxic T-cell precursors have been shown to occur in spleens of 2-3-day-old mice. By 12 days after birth, the cytotoxic T-cell response of spleen cells to alloantigens has reached 23-32% of adult levels. Addition of extra T-helper cells did not permit cytotoxic T-cell development in spleen cells from newborn to 2-day-old mice suggesting either a lack of precursors or suppression of precursors. The ontogeny of cell-mediated immune functions has thus been shown to correlate well with other work on the development of humoral immunity, accessory cells, and graft versus host reactivity.
Regulatory mechanisms in cell-mediated immune responses. V. H-2 homology requirements for the production of a minor locus-induced suppressor factor.
Authors: Kastner D L , Rich R R , Chu L , Rich S S
Published: June 2004

A mixed leukocyte reaction suppressor factor is produced by spleen cells sensitized in vivo and restimulated in vitro across non-H-2 antigenic barriers. Cells capable of producing this factor appear in the spleens of minor locus-immunized animals later than in animals sensitized to major histocompatibility complex-encoded antigens. However, both H-2 and non H-2-induced factors suppress proliferative responses to any alloantigen. Splenocytes from animals immunized with H-2-identical, minor locus-disparate cells produce suppressor factor in vitro only when restimulated with cells sharing both H-2 and non-H-2 antigens with the in vivo stimulators.
Specific enrichment of the suppressor T cell bearing I-J determinants: parallel functional and serological characterizations.
Authors: Okumura K , Takemori T , Tokuhisa T , Tada T
Published: June 2004

A simple procedure to enrich the antigen (keyhole limpet hemocyanin, KLH)-specific suppressor T cell was described. The suppressor T cell from KLH)-immunized mice specifically bound to the KLH-coated Sephadex G-200 column at 37 degrees C, and was eluted from the column by cold (0-4 degrees C) medium. The helper T cell did not bind to the column under the identical condition. The suppressor T cell thus obtained had 100 times as potent suppressor activity as the original spleen cells in in vivo and in vitro secondary antibody responses against a hapten coupled to KLH. This procedure also enriched the cells bearing I-J determinants and Lyt-2,3 alloantigens, allowing us to study the phenotypic expressions on the suppressor T cell by direct serological procedures as well as by the use of the fluorescence activated cell sorter. Parallel functional and serological analyses indicated that the antigen-specific suppressor T cell belongs to a population of I-J+, Lyt-2+,3+ and Fc R- T cells.
Passive transfer of autoimmune disease with isologous IgG1 and IgG2 antibodies to the tubular basement membrane in strain XIII guinea pigs: loss of self-tolerance induced by autoantibodies.
Authors: Hall C L , Colvin R B , Carey K , McCluskey R T
Published: June 2004

Initiation of an autoimmune tubulointerstitial disease was achieved in strain XIII guinea pigs by passive transfer of functionally pure IgG1 or IgG2 fractions of isologous anti-tubular basement membrane (TBM) serum. IgG2 appeared to be somewhat more effective than IgG1. The immunopathologic features in the IgG1 and IgG2 recipients were similar at the time of sacrifice, 14 days after transfer. The recipients that developed disease had higher than expected anti-TBM titers at 14 days. Furthermore, anti-TBM antibodies were of both IgG isotypes. In contrast, simultaneously administered IgG1 or IgG2 anti-BGG antibodies declined in titer in the recipients and were never found in the isotype fraction that had not been transferred. These findings indicate that the recipients of anti-TBM antibodies of either IgG1 or IgG2 isotype were stimulated to produce anti-TBM autoantibodies, which participated in the pathogenesis of the renal disease. The model demonstrates that autoantibodies may provide a mechanism (autoimmune amplification) for the intensification and perpetuation of antibody-mediated autoimmune diseases.
Analysis of H-2 and Ia molecules by two-dimensional gel electrophoresis.
Authors: Jones P P
Published: June 2004

Mouse lymphocyte H-2 and Ia glycoproteins have been analyzed with a two-dimensional (2-D) acrylamide gel electrophoresis technique, in which proteins are separated first according to their charge in isoelectrofocusing gels and then according to their size in sodium dodecyl sulfate gels. Individual polypeptide chains from radiolabeled cells are resolved as discrete spots on autoradiograms of the gels, forming patterns which are characteristic of the proteins in the sample. 2-D gels of H-2K, H-2D, and Ia glycoproteins immunoprecipitated from 35S-methionine-labeled cells reveal that these proteins exist in the cells as complex arrays of molecules heterogeneous in both size and charge. Lactoperoxidase-catalyzed radioiodination of lymphocyte surfaces labels only subsets of the total H-2 and Ia molecules with 125I, indicating that some of the molecules may represent cytoplasmic precursors of the cell surface proteins. This theory is supported by the kinetics of labeling of various spots in 35S-methionine pulse-chase experiments. The 2-D gel patterns obtained for both H-2 and Ia antigens have also been shown to be haplotype-specific and independent of the genetic background.
Quantitative studies on the precursors of cytotoxic lymphocytes. III. The lineage of memory cells.
Authors: H-S Teh , Phillips R A , Miller R G
Published: June 2004

In the course of a mixed lymphocyte culture, memory cells are produced which can give rise to a large secondary cytotoxic lymphocyte response on reexposure to the sensitizing alloantigen. We have studied the lineage of these memory cells using a clonal assay for precursors of cytotoxic T lymphocytes (CLP). Our data provide conclusive evidence that individual CLP, upon stimulation with alloantigens, gives rise to clones which contain memory cells of the same specificity as the CLP. Only half of the clones that responded in the primary stimulation could be reactivated upon exposure to the original priming alloantigen.
Origin of IgA-secreting plasma cells in the mammary gland.
Authors: Roux M E , McWilliams M , Phillips-Quagliata J M , Weisz-Carrington P , Lamm M E
Published: June 2004

Lymphoblasts from the mesenteric lymph nodes (MN) of mice home to the mammary glands of syngeneic recipients late in pregnancy and during lactation, and within hours of transfer most can be shown to contain IgA. Homing does not occur in virgins, in early pregnancy, or after weaning. Homing MN lymphoblasts are sensitive to antiserum to IgA plus complement, but not to other class-specific antisera. Thus, lymphoblasts in MN with the potential to home to the mammary gland are already committed to IgA synthesis and bear surface IgA before reaching their destination. These results explain observations, made by others, of specific IgA antibodies and IgA plasma cells in milk and colostrum after oral immunization. Under natural conditions it is likely that IgA precursor cells, after stimulation in the gut-associated lymphoid tissue by intestinal antigens, migrate to the mammary gland where they secrete antibodies which constitute an important defense mechanism of the newborn. In the absence of lactation, these cells probably form part of the normal traffic to the lamina propria of the small intestine.
Immune response of Lewis rats to peptide C1 (residues 68-88) of guinea pig and rat myelin basic proteins.
Authors: Kibler R F , Fritz R B , Chou F , C-H Jen Chou , Peacocke N Y , Brown N M , McFarlin D E
Published: June 2004

Peptide C1 (residues 68-88) from GP and rat BP differ by a single amino acid interchange at residue 79. This residue is serine in GP C1 and threonine in rat C1. GP C1 was encephalitogenic in Le rats at doses as low as 15 ng. Rat C1 was encephalitogenic at doses of 1,500 ng or greater. LNC from rats challenged with 25 X 10(-4) micronmol of GP C1 and 250 X 10(-4) micronmol of rat C1 showed a proliferative response in vitro to both peptides, but in each instance the magnitude of the response was greater to the GP peptide. GP C1 also induced higher levels of circulating antibodies at 25 X 10(-4) micronmol, but the specificity of antibodies produced by the two peptides was the same. These results have been interpreted as indicating that the presence of serine at position 79 in GP C1 results in the stimulation of greater numbers of T cells involved in (a) the induction of EAE, (b) the in vitro proliferative response and (c) helper function in antibody production.
H-2 effects on cell-cell interactions in the response to single non-H-2 alloantigens. II. H-2 D region control of H-7.1-specific stimulator function in mixed lymphocyte culture and susceptibility to lysis by H-7.1- specific cytotoxic cells
Authors: Wettstein PJ , Frelinger JA
Published: June 2004

The relative immunogenicity of the H-7.1 alloantigen has been shown in a previous communication to be regulated by a gene in the D region of the mouse major histocompatibility (H-2) complex. The level of relative immunogenicity was inferred from survival times of H-7.1-incompatible skin grafts donated by donors with different H-2 haplotype origins of H-2D region genes. In this communication we report the results of an extension of these previous investigations into the possible role of H-2D region genes in controlling the capacity of H-7.1-incompatible lymphocytes to stimulate H-7.1-speciflc mixed lymphocyte culture proliferation and generation of cytotoxic effector cells. The results reported herein demonstrate that the H-2D genotype of H-7.1-incompatible stimulator cells determines the relative H-7.1-specific capacity of those lymphocytes to stimulate H-7.1-specific proliferation of in vivo primed responder T cells in secondary mixed lymphocyte culture. H-2D(b)-bearing, H-7.l-incompatible stimulators were significantly more effective in stimulating H-7.1-specific proliferation than H-2D(d)-bearing stimulators. As expected, H-2D(b), H-7.1-in-compatible stimulators were also more effective than H-2D(d) a stimulators in generating H-7.1- specific cytotoxic effector cells. Further, the susceptibility of (51)Cr- labeled, H-7.1-incompatible lymphoblast targets to H-7.1-specific lysis was similarly regulated by an H-2D gene. Reciprocal H-2 restriction (F(1) cells are capable of killing only the cells bearing the immunizing cell parental H-2 haplotype) observed by other investigators for cytolysis of non-H-2-incompatible targets was not observed. H-2D a-bearing, H-7.1- incompatible stimulators stimulated generation of cytotoxic effectors capable of detectably lysing H-2D(b) but not H-2D(a)-bearing, H-7.1- incompatible targets. The impact of these observations on the proposed models for H-2 restriction of non-H-2 histocompatibility antigen-specific cytolysis is discussed.
Genetic control of cell-mediated responsiveness to an AKR tumor-associated antigen: mapping of the locus involved to the I region of the H-2 complex.
Authors: Meruelo D , Deak B , McDevitt H O
Published: June 2004

The role of H-2-linked genes in controlling resistance to murine leukemia viruses has been studied by measuring the cell-mediated immune response of F1 hybrid mice (between AKR and various C3H and C57BL/10 derived, H-2 congenic strains) to an AKR tumor cell line, BW5147. The studies have shown that the ability to generate a primary or secondary cell-mediated response to an AKR tumor cell antigenic determinant is under H-2 linked control. The locus determining CML responsiveness maps in the I-J subregion. Nonresponsiveness is associated with the H-2q/k and H-2b/k hybrid genotypes, whereas responsiveness is associated with the H-2k/k homozygous genotype. Nonresponsiveness may result from (a) dominant suppression; (b) recessive responsiveness; or (c) an alternate mechanism not yet understood. This type of control may be one of several H-2-associated mechanisms of defense against virus-induced neoplasms.
Nylon adherent antigen-specific rosette-forming T cells.
Authors: Cone R E , Gershon R K , Askenase P W
Published: June 2004

Shortly after intravenous immunization of mice with heterologous erythrocytes (RBC) antigen-specific Thy 1+ cells which form rosettes with the immunizing RBC (thymic-derived lymphocytes-forming rosettes [T-RFC]) appear in the spleen. These T-RFC are much less stable than Thy 1- RFC (non-thymic-derived [B-RFC]) although most if not all of both classes of RFC adhere to nylon. T-RFC are induced with low doses of antigen (which fail to induce B-RFC) and are inhibited by higher antigen doses which are optimal for induction of B-RFC. Pretreatment of mice with cyclophosphamide prevents the high dose inhibition of T-RFC. Although there are many parallels between the production of T-RFC and delayed-type hypersensitivity (DTH) it is unlikely that the T-RFC are essential for DTH reactions since DTH can be transferred with cells which pass through nylon, and such cells are almost totally depleted of T-RFC. Thus immunization can lead to the production of large numbers of antigen-specific T-RFC whose functional role in the immune response is unknown. However, the characteristics of the T-RFC suggest that they may play an important role in amplification of suppressor cell activity.