Biomedical subjects

H Jyonouchi

Publications and source records attributed to H Jyonouchi.

At least 37 records · Page 2Linked to original sources

PubMed1996

Nucleotide-free diet suppresses antigen-driven cytokine production by primed T cells: effects of supplemental nucleotides and dietary fatty acids.

Our previous studies suggest that nucleotides modulate T-helper (Th) cell-mediated antibody (Ab) production. This nucleotide action is influenced by dietary fatty acids. Herein, we report the effects of nucleotide-free (NF) diets normal or high in saturated fatty acid on antigen-driven Th cell activation by using cytokine production as an indicator. C57BL/6 mice were fed a NF diet, a NF diet plus mononucleotide and nucleoside mixture (OG-VI), a NF diet high in saturated fatty acid (NF-SFA), or a NF-SFA diet plus OG-VI. Mice were then challenged with neoantigen, a keyhole limpet hemocyanin (KLH). Regional draining lymph nodes were collected 5-7 d following antigen (AG) priming, rechallenged with KLH in the culture, and resultant cytokine production was measured. IFN gamma and IL-5 production was lower in mice fed a NF diet at protein and mRNA levels. IL-4 and IL-2 mRNA expression was also lower in mice fed a NF diet. IFN gamma protein levels were higher in mice fed a NF-SFA diet than in mice fed a NF diet, but production of other cytokines was equally suppressed in those fed a NF-SFA diet. In vivo OG-VI supplementation prevented aberrant cytokine production in mice fed a NF or NF-SFA diet. Polynucleotides added to the culture restored impaired IFN gamma and IL-5 production in mice fed a NF diet but did not further augment cytokine production in mice of other diet groups. These results indicate a potential role of nucleotides in Ag-driven Th-cell activation, and this nucleotide action is partly under the influence of dietary fatty acids.

Animals↗

PubMed1996

Effects of various carotenoids on cloned, effector-stage T-helper cell activity.

Astaxanthin, a carotenoid without provitamin A activity, enhances murine T-helper (Th) cell clone-mediated antibody (Ab) production with suboptimal antigen (Ag) challenges. It also suppresses interferon-gamma (IFN-gamma) production by cloned murine Th1 cells. beta-Carotene is less effective than astaxanthin. This study evaluates the effects of various carotenoids with various relative polarity, provitamin A activity, and antioxidant activity. Carotenoids tested include astaxanthin, cantaxanthin, zeaxanthin, lutein, and lycopene, and their effects were tested at a concentration at which astaxanthin's effect was most potent. A.E7 and CDC35 cells are used as representative type 1 and type 2 Th cell (Th1 and Th2) clones, respectively. In the Th1 clone, astaxanthin, but not other carotenoids, suppressed IFN-gamma production and increased the number of Ab-secreting cells with the use of primed spleen cells. With cultures of Th1 cells and unprimed spleen cells, astaxanthin and zeaxanthin augmented the number of immunoglobulin M Ab-secreting cells. In the cultures of Th2 clone and primed spleen cells, astaxanthin, but not other carotenoids, enhanced the number of Ab-secreting cells. With unprimed spleen cells, lycopene suppressed Th2 clone-mediated Ab production. Interleukin-5 production by the Th2 clone was not significantly altered with the carotenoids tested, irrespective of the use of unprimed or primed spleen cells. Carotenoid actions on Th cells may vary in each carotenoid and do not seem to be closely associated with carotenoid antioxidant activity or relative polarity.

Animals↗

PubMed1996

An orally supplemented mononucleotide mixture prevents the decrease in T cell-dependent humoral immunity in C57BL/6 mice fed a nucleotide-free diet.

T-cell-dependent humoral immune responses are lower in mice fed a nucleotide-free (NF) diet. In a previous study, a mononucleotide and nucleoside mixture prevented the decrease in humoral immune responses in mice fed a NF diet when a total of seven doses [2100 micromol/(kg x dose)] were administered intraperitoneally. In the present study, C57BL/6 (B6) mice were fed a NF diet for 3 wk with or without mononucleotide mixture (MM) supplementation. The MM was given at the levels of 14 or 70 micromol/(kg x d) by daily gavage feeding for 3 wk. Control mice were fed a NF diet without supplements (negative control) or a NF diet plus the mononucleotide/nucleoside mixture administered intraperitoneally (positive control). Both doses of MM prevented the decrease in T-dependent antibody (Ab) production in mice fed a NF diet as effectively as positive controls. T-helper (Th) spleen cells from mice of each diet group were enriched, mixed with Th cell-depleted spleen cells from each diet group, and antigen-primed in the culture. The number of Ab-secreting cells formed was higher with Th cells from mice with oral MM supplements or from positive controls than with those from mice without nucleotide supplement. The source of Th cell-depleted spleen cells did not influence the number of Ab-secreting cells. Thus, orally supplemented nucleotides can prevent the suppression of Th cell-dependent humoral immunity in mice fed a NF diet with doses likely to be provided by dietary sources.

Animals↗

PubMed1995

Effect of carotenoids on in vitro immunoglobulin production by human peripheral blood mononuclear cells: astaxanthin, a carotenoid without vitamin A activity, enhances in vitro immunoglobulin production in response to a T-dependent stimulant and antigen.

The effect of carotenoids on in vitro immunoglobulin (Ig) production by peripheral blood mononuclear cells (PBMNC) was examined by employing blood samples from adult volunteers and full-term newborn babies (umbilical cord blood). Under carotenoid-supplemented culture conditions, cells were stimulated by polyclonal stimulants, neoantigens, and a recall antigen (Ag), and IgM, IgA, and IgG levels in the culture supernatant were measured. Beta-carotene and astaxanthin were used as representatives of carotenoids with and without vitamin A activity, respectively. Astaxanthin enhanced IgM production in response to T-dependent Ag (TD-Ag) and a T-dependent polyclonal stimulant. Astaxanthin also augmented IgG production in response to a recall Ag. IgA production without supplemental carotenoids was negligible for all stimuli. However, in carotenoid-supplemented cultures, IgA production was significantly higher in response to a T-dependent polyclonal stimulant than in unsupplemented cultures. IgM and IgA production was augmented at 10(-8) mol/l astaxanthin, whereas astaxanthin enhanced IgG production in response to a recall Ag at 10(-10)-10(-9) mol/l. Similar enhancing actions of astaxanthin on IgM production were observed in cord blood mononuclear cells (CBMNC), although CBMNC produced less IgM than adult PBMNC. Beta-carotene did not have a significant effect on human Ig production. The carotenoid actions were not demonstrated under serum-free culture conditions; serum is essential for solubilization of carotenoids. In summary, this study has shown for the first time that astaxanthin, a carotenoid without vitamin A activity, enhances human Ig production in response to T-dependent stimuli.

Adult↗

PubMed1995

Astaxanthin, a carotenoid without vitamin A activity, augments antibody responses in cultures including T-helper cell clones and suboptimal doses of antigen.

Astaxanthin, a carotenoid without vitamin A activity, enhances T-dependent antigen (Ag)-specific humoral immune responses. We examined carotenoid actions on T-helper (Th) cell activity in a direct manner with reconstitution experiments; spleen Th cells were replaced with Ag-specific Type 1 and Type 2 (Th1 and Th2) Th cell clones. The Ag for the Th1 and Th2 clones were pigeon cytochrome C and rabbit gamma-globulin, respectively. Astaxanthin and beta-carotene augmented the number of IgM antibody (Ab)-secreting cells when unprimed B cells were incubated with Th clones and stimulated with suboptimal doses of Ag specific for each Th clone. The number of IgG Ab-secreting cells were greater with use of in vivo primed B cells than with unprimed B cells in both Th clones. Astaxanthin but not beta-carotene augmented the number of IgG Ab-secreting cells when primed B cells and Th cell clones were stimulated with suboptimal doses of Ag specific for each Th clone. In the presence of optimal doses of Ag for each Th clone, neither carotenoid augmented the number of Ab-secreting cells. Astaxanthin and beta-carotene may enhance the actions of both Th1 and Th2 cells for humoral immune responses with suboptimal Ag challenges; certain carotenoids may help maintain Ag-mediated immune responses at optimal levels.

Animals↗

PubMed1995

Polynucleotides compensate for impaired T-dependent antibody production induced in C57B1/6 mice by a nucleotide-free diet both in vivo and in vitro, but a mononucleotide-nucleoside mixture is effective only in vivo.

Actions of nucleotides on in vitro humoral immune responses were studied in mice fed a nucleotide-free diet, a nucleotide-free diet plus a mononucleotide-nucleoside mixture or a nucleotide-free diet plus yeast RNA (polynucleotides). Cultured spleen cells from mice fed a nucleotide-free diet produced fewer numbers of antibody-secreting cells in response to a T-dependent antigen, compared with those from controls fed nucleotide-supplemented diets. Immunoglobulin M concentrations in these supernatants were significantly lower in cultured cells from mice fed the nucleotide-free diet or the nucleotide-free diet plus the mononucleotide/nucleoside mixture compared with concentrations in cells from mice fed the nucleotide-free diet plus RNA. Concanavalin A-potentiated cytokine (interleukin-4 and interleukin-5) production by purified T helper cells was also lower in cultured cells from mice fed a nucleotide-free diet than in those from mice fed nucleotide-supplemented diets. In vivo supplementation with the mononucleotide/nucleoside mixture restored impaired in vitro antibody and concanavalin A-potentiated cytokine production in mice fed a nucleotide-free diet. However, addition of RNA to the culture enhanced antibody production in spleen cells from mice of all diet groups. Supplementing the culture with RNA did not enhance mitogen-potentiated cytokine production. This in vitro action of RNA was retained after the removal of oligonucleotides (molecular weight < 1000), but was reduced by modification of bases and cleavage of phosphodiester bonds of RNA. Thus the in vitro action of RNA is mainly attributed to polynucleotides, indicating their potential role in modulation of local humoral immune responses in the body.

Animals↗

PubMed1995

Mismatched bone marrow transplantation for Omenn syndrome: a variant of severe combined immunodeficiency.

Omenn syndrome is a variant of SCID, inherited as an autosomal recessive disorder, and characterized by severe eczematoid dermatitis, eosinophilia, elevated serum IgE and a distinctive histology in enlarged lymph nodes. The etiology of Omenn syndrome is unknown, however, unlike other forms of SCID; patients with Omenn syndrome have activated T lymphocytes in their circulation capable of non-MHC restricted cytotoxic function. Recently, it has been observed that the use of immunosuppressive therapy, particularly cyclosporine, can modify the clinical manifestations of the disorder. Prior to the use of bone marrow transplantation this disease was universally fatal. Death typically occurred in infancy as the result of opportunistic infections and/or malignancies, most notably lymphomas. While bone marrow transplantation has become quite successful for many phenotypes of SCID, even with the use of alternative donors other than histocompatible siblings, in Omenn syndrome it remains a challenge. In our experience, patients with Omenn syndrome exhibit a higher incidence of Gram negative sepsis, before and during transplantation, and carry a significant risk of post-transplant rejection when compared with patients with other phenotypes of SCID. We report the results of six patients treated with bone marrow transplantation from alternative donors, three had unrelated donors (URD) and three had haplo-identical parental donors. Five of the six patients achieved complete and/or durable donor cell engraftment and only one patient experienced acute GVHD. Three patients died of transplant-related complications (infection or EBV-associated B cell lymphoma) between day +22 and day +95 post-transplant. Three patients survived more than 1 year post-transplant.(ABSTRACT TRUNCATED AT 250 WORDS)

Bone Marrow Transplantation↗

PubMed1994

Immunosuppression: preliminary results of alternative maintenance therapy for familial hemophagocytic lymphohistocytosis (FHL).

Hemophagocytic lymphohistiocytosis (HLH) describes a group of disorders with similar clinical features that are associated with a very high mortality rate. Patients with HLH, and particularly the infantile form referred to as familial hemophagocytic lymphohistiocytosis (FHL), are often treated with multiple courses of epipodophyllotoxins, such as etoposide, for prolonged periods of time. Because of the concern regarding the risk of epipodophyllotoxin-induced acute myelogenous leukemia (AML) we have explored the use of immunosuppression as maintenance therapy for patients with FHL while they await the only known definitive treatment, i.e., bone marrow transplantation (BMT). We report 2 infants with FHL who had significant central nervous system involvement at diagnosis. Both were initially treated with etoposide, methotrexate, and glucocorticosteroids. Once clinical improvement was achieved these patients were successfully maintained in clinical remission of FHL on daily cyclosporine A (CSA) and glucocorticosteroids along with intermittent intrathecal methotrexate for 5 months until appropriate unrelated donors could be identified for BMT.

Cyclosporine↗

PubMed1994

Immunomodulating actions of carotenoids: enhancement of in vivo and in vitro antibody production to T-dependent antigens.

Previously, we demonstrated an enhancement of in vitro antibody (Ab) production in response to T-dependent antigens (TD-Ag) by astaxanthin, a carotenoid without vitamin A activity. The effects of beta-carotene, a carotenoid with vitamin A activity, and lutein, another carotenoid without vitamin A activity, on in vitro Ab production were examined with spleen cells from young and old B6 mice. In addition, the in vivo effects of lutein, astaxanthin, and beta-carotene on Ab production were studied in young and old B6 mice. Lutein, but not beta-carotene, enhanced in vitro Ab production in response to TD-Ags. The depletion of T-helper cells prevented the enhancement of Ab production by lutein and astaxanthin. In vivo Ab production in response to TD-Ag was significantly enhanced by lutein, astaxanthin, and beta-carotene. The numbers of immunoglobulin M- and G-secreting cells also increased in vivo with the administration of these carotenoids when mice were primed with TD-Ags. Antibody production in response to TD-Ags in vivo and in vitro was significantly lower in old than in young B6 mice. Astaxanthin supplements partially restored decreased in vivo Ab production in response to TD-Ags in old B6 mice. Lutein and beta-carotene also enhanced in vivo Ab production in response to TD-Ags in old B6 mice, although to a lesser extent than did astaxanthin. However, none of the carotenoids had an effect on in vivo or in vitro Ab production in response to T-independent antigen. These results indicate significant immunomodulating actions of carotenoids for humoral immune responses to TD-Ags and suggest that carotenoid supplementation may be beneficial in restoring humoral immune responses in older animals.

Adjuvants, Immunologic↗

PubMed1994

Nucleotide-free diet impairs T-helper cell functions in antibody production in response to T-dependent antigens in normal C57B1/6 mice.

We have previously shown that polynucleotides enhance in vitro antibody production in response to T-dependent antigens. This study examines the importance of dietary nucleotides on in vivo antibody production in response to antigen stimuli. C57Bl/6 mice fed a nucleotide-free diet for more than 3 wk demonstrated significantly lower antibody production to T-dependent antigens both in vivo and in vitro compared with control mice fed a nonpurified diet. Numbers of immunoglobulin M and G secreting cells in the spleen were also lower in mice fed a nucleotide-free diet after the challenge of T-dependent antigens compared to the controls. Responses to T-independent antigens remained intact in mice fed a nucleotide-free diet. T-helper cells from mice fed a nucleotide-free diet were less capable of inducing T-dependent antibody production in vitro compared with those from mice fed a nonpurified diet. Intraperitoneal injection of a mononucleotide-nucleoside mixture restored T-helper cell functions and T-dependent antibody production in mice fed a nucleotide-free diet. These results may indicate the importance of dietary nucleotides in maintaining optimal T-helper cell functions for humoral immune responses in response to T-dependent antigens.

Animals↗

PubMed1994

Nucleotide actions on humoral immune responses.

Previous studies indicate the importance of dietary nucleotides in maintaining optimal cellular immunity. Our studies using murine spleen cells showed that polynucleotides significantly increase in vitro antibody production in response to T-cell-dependent antigen. They seem to exert actions on T-helper cells at antigen presentation, perhaps during cognitive cell-cell interactions. They do not augment the actions of cloned, antigen-specific, activated T-helper cells, nor do they increase antibody production in response to T-cell-independent antigen or polyclonal B-cell activation. Polynucleotides increase in vitro human immunoglobulin production in response to T-cell-dependent stimuli and antigen. Humoral immune responses to T-cell-dependent antigen were depressed in mice fed a nucleotide-free diet, but were restored by a mononucleotide-nucleoside mixture. Responses to T-cell-independent antigen remained intact in these mice. The mononucleotide-nucleoside mixture had no effect on in vitro antibody production and did not further increase humoral immune responses in mice fed regular lab chow. These results suggest that the in vivo actions of polynucleotides on humoral immune responses may reflect local immune responses, perhaps at the site of inflammation. Mononucleotides and nucleosides may be incorporated into the tissue nucleotide pool fairly rapidly in a state of relative nucleotide deficiency and help restore T-cell-dependent humoral immune responses. Our findings may further support the importance of dietary nucleotides.

Animals↗

PubMed1993

Studies of immunomodulating actions of carotenoids. II. Astaxanthin enhances in vitro antibody production to T-dependent antigens without facilitating polyclonal B-cell activation.

Previously we have shown that astaxanthin, a carotenoid without provitamin A activity, enhances in vitro antibody (Ab) production to sheep red blood cells in normal B6 mice. In this study, we further attempted to examine the mechanisms of this enhancing action of carotenoids on specific Ab production in vitro in relation to different antigen (Ag) stimuli, cytokine production, and T- and B-cell interactions in both normal and autoimmune strains of mice. When the actions of carotenoids were tested in normal strains of mice, we found that astaxanthin enhanced in vitro Ab production to T cell-dependent Ag, but not to T-independent Ag, and did not augment total immunoglobulin production. Astaxanthin exerted maximum enhancing actions when it was present at the initial period of Ag priming. This action of astaxanthin was abolished when T cells were depleted from spleen cell suspensions and appeared to require direct interactions between T and B cells. The results also indicated that carotenoids may modulate the production of interferon-tau in this assay system. When the actions of carotenoids were tested in autoimmune-prone MRL and NZB mice, the enhancing action of astaxanthin on in vitro Ab production was less significant. Furthermore, carotenoids did not potentiate or augment spontaneous Ab and immunoglobulin production by spleen cells in these strains. Taken together, carotenoids without provitamin A activity may be able to augment in vitro specific Ab production to T cell-dependent Ag partly through affecting the initial stage of Ag presentation without facilitating polyclonal B-cell activation or autoantibody production.

Adjuvants, Immunologic↗

PubMed1993

Studies of immunomodulating actions of RNA/nucleotides. RNA/nucleotides enhance in vitro immunoglobulin production by human peripheral blood mononuclear cells in response to T-dependent stimuli.

We have shown previously that yeast RNA preparations enhance in vitro antibody and Ig production to T-dependent antigens in normal B6 mice. In this study, Ig production by human peripheral blood mononuclear cells from adult volunteers was examined under RNA and mononucleotide-supplemented culture conditions. RNA significantly enhanced IgM and IgG production in a dose-dependent manner to pokeweed mitogen, T-dependent stimuli, and keyhole limpet hemocyanin modified with trinitrophenol, T-dependent antigens. IgM and IgG production in response to T-independent stimuli were not significantly altered by RNA and mononucleotides. IgA production appeared not to be influenced by RNA and mononucleotides irrespective of the stimuli provided. Interestingly, spontaneous IgM production also appeared to be enhanced by RNA. When RNA was degraded, oxidized, or decomposed of pyrimidine bases, this enhancing action of RNA on Ig production was considerably reduced. RNA was most effective when present from d 0 of the culture. Its enhancing action was lost when it was added at d 3 of the culture or later, when T cells were depleted, or when direct interactions between T cells and non-T cells were not permitted in the culture. Thus, RNA may enhance IgM and IgG production by human peripheral blood mononuclear cells to T-dependent stimuli partly by influencing the process of direct cellular interactions between T and non-T cells in the early stage of B-cell activation.

Adjuvants, Immunologic↗

PubMed1993

Immunomodulating actions of nucleotides: enhancement of immunoglobulin production by human cord blood lymphocytes.

We have shown previously that polynucleotides enhance in vitro antibody and Ig production in response to T-dependent antigens in mice and augment Ig production by adult human peripheral blood mononuclear cells. Herein, we report their effects on umbilical cord blood mononuclear cells (CBMNC) obtained from full-term babies. CBMNC produced much less IgM/IgG and an almost negligible amount of IgA in response to various stimuli compared with adult peripheral blood mononuclear cells. The supplementation of yeast RNA augmented spontaneous and T-dependent IgM (p < 0.01) but not IgG production by CBMNC. This action was largely attributable to polynucleotides, which appeared to exert their actions in a dose-dependent manner at the initial stages of culture. Their actions were dependent upon the presence of T cells, but they also enhanced spontaneous IgM production by CBMNC in the absence of T cells. Preincubation of T cells from CBMNC and peripheral blood mononuclear cells with RNA for 3 h before the culture resulted in enhanced IgM production, independent of the stimulants used. Thus, polynucleotides appear to exert actions on immature human T cells as well as other lineage cells in vitro. Their actions may be dependent on the presence or absence of antigens or other stimuli and the nature of the stimuli (T dependent versus T independent). These findings may further support the potential importance of nucleotides contained in human breast milk.

Adjuvants, Immunologic↗

PubMed1993

Preventive action of carotenoids on the development of lymphadenopathy and proteinuria in MRL-lpr/lpr mice.

The chemopreventive action of carotenoids on proteinuria and lymphadenopathy were examined in autoimmune-prone MRL-lpr/lpr (MRL/l) mice. They were fed a synthetic full-fed diet (16-18 kcal/mouse/day) with supplementation of beta-carotene or astaxanthin (0.19 mumoles/mouse, 3 times a week), and the development of lymphadenopathy and proteinuria were examined. MRL/l mice fed a full-fed diet without the supplementation of carotenoids or those fed a calorie-restricted (CR) diet (10-11 kcal/mouse/day, 60% calorie intake of full-fed mice) were employed as controls. CR dramatically delayed the development of proteinuria and lymphadenopathy, as reported previously. Carotenoids also significantly delayed the onset of these symptoms in MRL/l mice fed a full-fed diet. Carotenoids were half as effective as CR and astaxanthin, a carotenoid without provitamin A activity, which appeared to exert more significant preventive actions than beta-carotene in delaying the development of these symptoms. Similar chemopreventive actions of carotenoids were also demonstrated in MRL/l mice fed a regular diet (Lab Chow). CR has been shown to augment IL-2 production and to decrease serum prolactin levels in this strain, which may be related to its dramatic preventive action of autoimmunity. However, carotenoids did not affect IL-2 production nor prolactin levels in full-fed MRL/l mice. The chemopreventive actions of carotenoids observed in autoimmune-prone MRL/l mice may be attributed to yet unknown mechanisms, apart from their provitamin A activity or oxygen-quenching activity.

Animals↗

PubMed1992

RNA/nucleotide enhances antibody production in vitro and is moderately mitogenic to murine spleen lymphocytes.

Suppression of immune functions was demonstrated in both humans and animals when exogenous RNA was eliminated from the diet. However, direct actions of RNA/nucleotide on the immune system are virtually unknown. Thus, in this study, we explored effects of RNA and nucleotide on lymphocyte functions in vitro. Yeast whole RNA, which is free of endotoxin, was supplemented to culture media, and changes in mitogen responses, thymocyte proliferation, or in vitro antibody production by murine spleen lymphocytes were analyzed. Yeast whole RNA potentiated the proliferation of spleen lymphocytes and it also strikingly enhanced in vitro antibody production in response to sheep red blood cells at least 10-fold. However, it did not potentiate the proliferation of thymocytes (immature lymphocytes). These enhancing activities of yeast RNA were significantly reduced by RNAse treatment, but not by treatments with DNAse or polymyxin B. Certain mononucleotides exhibited less, but similar, action on murine spleen lymphocytes. The whole yeast RNA employed was already degraded to small nucleotide (less than 1 kb). Therefore, it may be suggested that certain components of RNA degraders can function as powerful immunomodulators, indicating that exogenous RNA or nucleotide may be important in facilitating immune responses under certain circumstances.

Animals↗

PubMed1991

NZB serum factor (NZB-SF): B precursor cell maturation factor identified in murine lupus. I. Identification of 60-kDa glycoprotein as the major component from both spleen cell supernatant and serum.

NZB serum factor (NZB-SF), initially identified in sera of very young NZB mice, can enhance maturation and proliferation of sIg- pre-B cells in marrow. In the present study, spleen cell supernatant from young NZB mice was used as a source of NZB-SF. NZB mice were treated with Corynebacterium parvum 2 weeks prior to sacrifice, and harvested spleen cells obtained at sacrifice were cultured for 24 hr in serum-free medium. One liter of spleen cell supernatant prepared in this way contained NZB-SF-like activity equivalent to that present in 10 ml of serum collected from young NZB mice. NZB-SF was purified on an affinity chromatographic column conjugated with mouse IgG1 monoclonal antibody (mAb) against NZB-SF. The purified NZB-SF had pI 7.8 and showed one major band of 60 kDa and a faintly stained 35-kDa band upon SDS-PAGE under nonreducing conditions. The 60-kDa NZB-SF extracted from the gel slice was also more potent in dot blot ELISA (greater than 100 times) than the 35 kDa NZB-SF and was biologically active. After endoglycosidase F treatment, but not after treatment with a reducing agent (2-ME), the two bands merged into a single band at the 15-kDa position. Amino acid sequence analysis of endo-F treated NZB-SF indicated that the N-terminus of this protein is blocked. Serological and functional studies of affinity-purified NZB-SF have revealed that NZB-SF is distinguishable from IL-1 alpha, IL-2, IL-3, IL-4, IL-5, IL-6, CSF-GM, IFN-gamma, and TNF alpha. Therefore, a major component of NZB-SF(s) in the spleen cell supernatant may be an apparently novel 60-kDa glycoprotein with a single amino acid backbone. Sera and spleen cell supernatants from normal strains of mice (DBA/2, B6, or BALB/c) were also applied to the immuno-affinity column used to purify NZB-SF. It was found that trace amounts of NZB-SF are present also in serum of normal strains of mice and that spleen cells of these mice can also produce NZB-SF in vitro following stimulation with C. parvum. In SDS-PAGE, the 60-kDa NZB-SF is also the major component of NZB-SF in normal strains of mice. These results suggest that the 60-kDa NZB-SF may be of physiological importance in B cell differentiation and that this physiological factor is autoimmune-prone NZB mice.

Animals↗

PubMed1991

NZB serum factor (NZB-SF)-B precursor cell maturation factor. II. In vivo effects of NZB-SF or mAb against NZB-SF on B lineage cell populations.

In vivo effects of NZB serum factor (NZB-SF), which enhances the maturation of B precursor cells in vitro, were examined. Immunoaffinity-purified NZB-SF from young NZB mice was injected into B6 mice intraperitoneally twice weekly, five times total (5 micrograms/dose/mouse). Control mice were given 0.01% albumin. Then the B lineage cell populations defined phenotypically (sIg+ cells, B220+ cells, and AA4.1+ cells) or the numbers of colony-forming B lineage cells were examined. NZB-SF-treated B6 mice exhibited a decrease in the percentage of B precursor cells in marrow, even though the percentage of sIg+ cells in marrow or spleen did not differ from controls. In contrast, the frequency of colony-forming B cells in marrow and spleen, especially sIg- colony-forming B cells in marrow, increased significantly in NZB-SF-treated mice as compared to controls. In addition, monoclonal antibody (mAb) against NZB-SF was injected weekly for 9 weeks into NZB mice beginning at 7 weeks of age. mAb vs NZB-SF at a dose of 5 micrograms per mouse per injection, as stated above, prevented the decline of sIg- colony-forming B lineage cells which usually occurred in the adult NZB mice (greater than 16 weeks). This treatment also prevented, in part, the decline of the B220+ cell population which normally occurs in the marrow with increasing age. Thus NZB-SF impressively influences the composition of B lineage cell populations in normal B6 mice and may account for abnormal changes of B lineage cell populations observed in NZB mice.

Animals↗