Biomedical subjects

K Nomoto

Publications and source records attributed to K Nomoto.

At least 199 records · Page 11Linked to original sources

PubMed1996

The role of p56lck in the development of gamma delta T cells and their function during an infection by Listeria monocytogenes.

We investigated roles of p56lck tyrosine kinase (Lck) on the development and function of gamma delta T cells in adult mice using lck gene knockout (lck -/-) mice. The mature gamma delta T cells (heat-stable Ag negative) were generated significantly in the thymi of adult lck -/- mice. When Listeria monocytogenes was infected i.p., gamma delta T cells were induced in the peritoneal cavity of the lck -/- mice. Interestingly, the repertoire of gamma delta T cells was obviously different in the lck +/+ and lck -/- mice; i.e., the gamma delta T cells of the lck -/- mice induced by the listerial infection dominantly expressed V delta 1 while those of the lck +/+ mice dominantly expressed V delta 6. The V delta 1 + gamma delta T cells in the lck -/- mice were extrathymically generated, supported by their appearance in thymectomized irradiated mice reconstituted with bone marrow cells from the lck -/- mice. Furthermore, the gamma delta T cells of the lck +/+ mice were protective in the early stage of the listerial infection, while the gamma delta T cells in the lck -/- mice were not protective against the listerial infection because the depletion of the gamma delta T cells from the lck -/- mice did not influence the bacterial burden in the spleens. These observations thus suggest that 1) gamma delta T cells can develop in adult mice through the intrathymic and extrathymic pathways even in the absence of Lck, 2) Lck influences the expansion and the repertoire of gamma delta T cells, and 3) the gamma delta T cells raised in the absence of Lck are not protective against L. monocytogenes.

Animals↗

PubMed1996

Extracellular ATP activates mast cells via a mechanism that is different from the activation induced by the cross-linking of Fc receptors.

In this study, the extracellular ATP (ATPo)-induced biochemical events were elucidated by comparing them with either the Fc epsilon RI- or Fc gamma R-induced events in the mouse mast cell line MC9. The omission of extracellular Ca2+ almost completely abolished the elevation of intracellular Ca2+ ([Ca2+]i) in the ATPo-stimulated cells, but only suppressed the second phase of the increase of [Ca2+]i in FcR-stimulated cells, thus suggesting that the ATPo-induced elevation of [Ca2+]i is totally dependent on the entry of extracellular Ca2+. Pretreatment with genistein, which inhibits protein kinases, especially protein tyrosine kinase, inhibited the FcR-triggered increase of [Ca2+]i, but not the ATPo-triggered one; however, such pretreatment did suppress both ATPo- and FcR-mediated beta-hexosaminidase release. An immunoblot analysis revealed that both ATPo and the cross-linking of FcRs led to tyrosine phosphorylation of 44- and 110-kDa proteins, which thus suggested that these tyrosine-phosphorylated proteins are involved in a modulation of the degranulation process following an elevation of [Ca2+]i. Pretreatment with PMA inhibited the FcR-induced [Ca2+]i increase, while not inhibiting the ATPo-induced one, thus suggesting that ATPo can mobilize [Ca2+]i even when protein kinase C (PKC) has already been activated. Pretreatment of calphostin C, a specific PKC inhibitor, had little effect on the ATPo-mediated beta-hexosaminidase secretion, thus indicating that the ATPo-induced degranulation is not mediated by PKC. Taken together, these results demonstrate that ATPo activates MC9 mast cells by a mechanism that is different from the activation induced by the cross-linking of FcRs.

Adenosine Triphosphate↗

PubMed1996

Differential effects of viable and killed bacteria on IL-12 expression of macrophages.

Listeria monocytogenes-specific, IFN-gamma-producing CD4+ T cells are induced in 5-day in vitro cultures of naive spleen cells with viable L. monocytogenes (VLM) but are not induced in cultures with heat killed L. monocytogenes (HKLM). Anti-IL-12 Abs abrogated the induction of the IFN-gamma-producing CD4+ T cells by VLM, suggesting an importance of IL-12 in the induction of IFN-gamma-producing CD4+ T cells. Accordingly, IL-12p40 was expressed by macrophages (M phi) from the cultures of whole spleen cells with VLM but not with HKLM, although HKLM induced IL-12p40 expression on M phi when nonadherent cells were removed before culture. In vivo analysis also showed that VLM induced IL-12p40 expression by M phi, whereas HKLM failed to induce it. On the other hand, the addition of anti-IL-10 mAb into cultures of whole spleen cells and HKLM resulted in an increase of IL-12p40 expression by M phi. Furthermore, we detected an expression of IFN-gamma by both adherent and nonadherent spleen cells at the early stage of stimulation with VLM before the appearance of IFN-gamma-producing CD4+ T cells. These data suggest that HKLM induce nonadherent spleen cells to produce IL-10 which may down-regulate IFN-gamma-producing CD4+ T cells by blocking IL-12 production by M phi. In contrast, VLM support IFN-gamma production by CD4+ T cells by stimulating M phi to produce IL-12 and IFN-gamma.

Animals↗

PubMed1996

Donor-specific prolongation of rat skin graft survival induced by rat-donor cells and cyclophosphamide under coadministration of monoclonal antibodies against T cell receptor alpha beta and natural killer cells in mice.

Because of the recent interest in human xenotransplantation, we investigated the possibility of inducing tolerance in a xenogeneic combination using cyclophosphamide (CP). Donor-specific prolongation of xenogeneic Fisher 344 (F344) rat skin graft survival for up to 60 days was induced in C57BL/6 (B6) mice by giving F344 bone marrow cells and spleen cells on day 0, CP on day 2, and monoclonal antibodies against murine TCR-alpha beta and NK1.1 on days--1 and 3. The inoculation of the xenogeneic cells brought accelerated repopulation of TCR-alpha beta+ T cells, even under the administration of anti-TCR-alpha beta mAb. The quick increase of the host TCR-alpha beta+ T cells caused by the xenogeneic cell injection was deeply suppressed by CP. Mixed lymphocyte reaction, CTL activity, and antibody production against donor F344 were profoundly suppressed for 50 days. Mixed xenogeneic chimerism was observed for 1 month after the inoculation of donor cells in the spleen and peripheral blood of the recipient B6 mice, but was never observed in the thymus. Moreover, when irradiated F344 cells were used in place of viable cells, chimerism was never detected and graft survival was only slightly prolonged. Clonal deletion of V beta 5- or V beta 11-bearing murine T cells was not observed on day 50 in the thymus or spleen of the recipient B6 mice. These results suggest that treatment with viable xenogeneic donor cells, CP, and mAbs against T and NK cells can induce a temporary peripheral mixed chimerism and donor-specific prolongation of xenogeneic skin graft survival. The destruction with CP of T and B cells that are xenoreactive and thus proliferating after antigen stimulation, followed by mechanism other than intrathymic clonal deletion, may be the mechanism of the hyporesponsiveness in the present system.

Animals↗

PubMed1996

Cytokine messenger RNA expression in the labial salivary glands of patients with Sjögren's syndrome.

OBJECTIVE: To characterize the initiation and progress of localized autoimmune damage in Sjögren's syndrome (SS), an autoimmune disease that is also considered to be a lymphoaggressive disorder, by examining the pattern of cytokine production at the site of autoimmune damage. METHODS: Using a polymerase chain reaction-based method, cytokine messenger RNA (mRNA) expression in the labial salivary glands of 15 patients with SS was investigated. In addition, the infiltrating lymphocytes in the labial salivary glands were examined immunohistochemically. RESULTS: Messenger RNAs of Th1 cytokines, such as interleukin-2 (IL-2) and interferon-gamma, were consistently detected in all patients, while Th2 cytokine mRNAs, such as IL-4 and IL-5, were detected in some cases, in association with strong B cell accumulation in the labial salivary glands. Other cytokine mRNAs produced by a variety of cell types, including IL-10, IL-6, and transforming growth factor beta (TGF beta), were also consistently detected in all patients, while IL-12 mRNA was detected in some of the patients. CONCLUSION: These results suggest that Th1 cytokines, as well as IL-10, IL-6, and TGF beta, are essential in the induction and/or maintenance of SS, while Th2 cytokines are involved in the progression of the disease process, especially local B cell activation.

Adult↗

PubMed1996

Assignment of the gene encoding type 1 gamma protein phosphatase catalytic subunit (PPP1CC) on human, rat, and mouse chromosomes.

Using fluorescent in situ hybridization (FISH) method, a gene encoding the catalytic subunit of protein phosphatase type 1 gamma (PPP1CC) was mapped to human 12q24.1-q24.2, rat 7 q22, and mouse 10C. These results indicate that the PPP1CC is a member of conserved synteny group between rat chromosome 7, mouse chromosome 10 and human chromosome 12. These data and mapping data about other members of PP1 family show that in spite of the high identity of PP1 isoforms, each isoform is encoded by different genes which located on different chromosomes in human, rat, and mouse.

Animals↗

PubMed1996

Effect of Z-100, an immunomodulator extracted from human type tubercle bacilli, on the pulmonary metastases of Lewis lung carcinoma in attempt to regulate suppressor T cells and suppressor factor, IL-4.

In the present study, anti-metastatic effect of Z-100 on the spontaneous pulmonary metastases of Lewis lung carcinoma (3LL) was examined in an attempt to regulate suppressor T cells. When Z-100 (10 mg/kg) was daily injected i.p. after 3LL inoculation, survival rate of these mice was increased significantly (p < 0.05). In addition, the number of pulmonary metastatic colonies of 3LL in Z-100-treated mice were significantly decreased by 38% at 21 days, as compared with that of control mice (p < 0.05). Along with the decrease of pulmonary metastases, suppressor cell activity was also gradually reduced in these mice, as compared with that of control mice. When splenic suppressor cells (5 x 10(7) cells) from 3LL-bearing mice were adoptively transferred into normal mice (recipients) just before inoculation of 3LL, the development of pulmonary metastases in recipients was significantly accelerated. However, splenocytes from 3LL-bearing mice treated with Z-100 did not affect the development of pulmonary metastasis. The potential to accelerate the metastasis of splenic mononuclear cells from 3LL-bearing mice was decreased significantly by the treatment with anti-Thy 1.2 monoclonal antibody (mAb), anti-Lyt 2.2 mAb or anti-CD 11b mAb followed by complement. IL-4 activity in the sera of 3LL-bearing mice was detected 15 days after tumor inoculation (13 pg/ml) and gradually increased (18 pg/ml) 20 days after tumor inoculation. However, when Z-100 (10 mg/kg) was daily injected i.p., IL-4 activity in sera was decreased significantly, and the IL-4 activity was not detected in these mice on day 20. These results suggest that Z-100 could inhibit the pulmonary metastases in 3LL-bearing mice through the inhibition of suppressor T cell activity and a possible candidate of its effector molecule, IL-4.

Adjuvants, Immunologic↗

PubMed1996

Protective effect of an acidic glycoprotein obtained from culture of Chlorella vulgaris against myelosuppression by 5-fluorouracil.

An acidic glycoprotein prepared from a culture of Chlorella vulgaris (CVS) was examined for its protective effect on 5-fluorouracil(5FU)-induced myelosuppression and indigenous infection in mice. Subcutaneous administration of CVS greatly reduced the mortality of non-tumor-bearing mice given a high dose of 5FU, and could increase the LD50 value of 5FU for these mice. After 5FU treatment, indigenous infection developed probably as a result of the impairment of the host defense system. CVS reduced the incidence of indigenous infections and this effect was attributable to the acceleration of recovery from 5FU-induced myelosuppression. Early recovery of hematopoietic stem cells, or cells responding to interleukin-3 or granulocyte/macrophage-colony-stimulating factor, was especially observed in the bone marrow of CVS-treated mice on days 4-9 after the injection of 5FU. When tumor-bearing mice were given CVS during treatment with 5FU, CVS prolonged the survival of mice without affecting the antitumor activity of 5FU. In addition, CVS was itself shown to exert an antitumor effect. These results suggested that CVS may be beneficial for the alleviation of side-effects in cancer chemotherapy without affecting the antitumor activity of the chemotherapeutic agent.

Animals↗

PubMed1996

T cell receptor V alpha and V beta gene usage by tumour-infiltrating lymphocytes in oral squamous cell carcinoma.

Oral squamous cell carcinomas (SCC) are often infiltrated by a large number of T lymphocytes. To clarify the nature of the tumour-infiltrating lymphocytes (TIL), we examined T cell receptor (TCR) V alpha and V beta gene usage by TIL and peripheral blood mononuclear cells (PBMC) obtained from 10 patients with oral SCC. We obtained RNA from TIL and PBMC, synthesized complementary DNA, and used the polymerase chain reaction (PCR) method with a panel of primers specific for the V gene segment subfamily (V alpha 1-18/V beta 1-20). We thus found that TIL showed more restricted usage of V beta gene families in contrast to PBMC of the same patients while two unique V beta gene (V beta 6 and V beta 5.2) segment transcripts were overexpressed in the TIL of more than half of the patients. On the other hand, no major difference was observed in the V alpha gene usage between the TIL and PBMC of most patients. To characterize these T cell subpopulations with unique V beta gene segment transcripts further, we sequenced the complementarity-determining region 3 in V beta 6-C beta and V beta 5.2-C beta PCR products derived from TIL and PBMC of two selected patients in each case. Although no usage of the conserved amino acid sequence by TIL was detected, the frequent use of V beta 6/J beta 1.1 in one patient and the V beta 6/J beta 2.7 gene segments in another patient was observed. Regarding the V beta 5.2 transcripts, obtained from the other two patients, no preferential usage of specific J beta gene segments by TIL was observed. These results suggest that the unique T cell populations are amplified in patients with oral SCC, possibly as a consequence of an in situ immune reaction.

Adult↗

PubMed1996

The concurrent administration of OK432 augments the antitumor vaccination effect with tumor cells by sustaining locally infiltrating natural killer cells.

The effect of a local injection with a streptococcal preparation OK432 on the antitumor vaccination with tumor cells was investigated. Natural killer (NK) cells, which were detected by anti-NK1.1 monoclonal antibody (mAb), increased in the peritoneal exudate cells after an intraperitoneal (i.p.) injection with syngeneic B16 melanoma cells. Furthermore, a concurrent i.p. injection with OK432 efficiently sustained the locally infiltrating NK cells. The OK432 treatment also sustained the augmented NK and lymphokine-activated killer activities in the peritoneal exudate cells. This treatment also increased the ability of the locally infiltrating NK cells to produce interferon gamma in response to the tumor cells. In addition, the concurrent i.p. injection with OK432 in combination with the tumor cells enhanced the capacity of the spleen cells to turn into anti-(B16 melanoma) cytotoxic T lymphocytes after in vitro restimulation. This augmenting effect of OK432 was dependent on NK cells. Moreover, the concurrent injection with OK432 at the time of anti-tumor vaccination significantly enhanced the protective immunity against B16 melanoma at the rechallenge. Taken together, these findings indicate that a concurrent local injection with OK432 in combination with tumor cells efficiently augments the antitumor vaccination effect, in part, by sustaining the locally infiltrating activated NK cells.

Adoptive Transfer↗

PubMed1996

Effects of interleukin-12 on in vitro culture with interleukin-2 of regional lymph node lymphocytes from lung cancer patients.

In the present study, we carried out a functional analysis of regional lymph node lymphocytes (RLNL) from patients with lung cancer after in vitro activation by interleukin-2 (IL-2) and interleukin-12 (IL-12). IL-12 (100 U/ml) enhanced both the proliferation and cytotoxic activity of RLNL in a culture with low doses of IL-2 (5-10 JRU/ml). After comparing an RLNL culture with a low dose of IL-2 alone, a higher proportion of CD8+ cells and CD56+ cells and a lower proportion of CD4+ cells were found in the culture with both IL-12 and a low dose of IL-2. Such a combination of the cytokines effectively activated RLNL in terms of the expression of IL-2 receptors. In the culture condition of IL-12 and a low dose of IL-2, a synergistic effect was observed in the production of such cytokines as interferon gamma, tumor necrosis factor alpha (TNF alpha), and TNF beta, as well as in tumor cytotoxicity. However, the addition of IL-12 inhibited the cytotoxicity of RLNL in the culture with a high dose of IL-2 (100 JRU/ml). This inhibition is considered to be partially due to the endogenous production of TNF alpha by lymphocytes, because the neutralization of TNF alpa bioactivity partially restored the cytotoxic activities of RLNL. Furthermore, in the presence of hydrocortisone, IL-12 synergistically enhanced the cytotoxic activity of RLNL cultured with a high dose of IL-2. These results provide useful information about the improvement of adoptive immunotherapy against cancer using RLNL.

Antigens, CD↗

PubMed1996

Effects of different inhibitors of 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase, pravastatin sodium and simvastatin, on sterol synthesis and immunological functions in human lymphocytes in vitro.

It has been shown previously that 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (HMG-CoA RIs) such as compactin and lovastatin suppress human lymphocyte functions in vitro (Cuthbert and Lipsky, 1981; Cutts and Bankhurst, 1989). Although it is not fully understood what inhibitory role the HMG-CoA RIs perform in causing this suppression, we show in this study that a certain inhibition threshold (inhibition level > 90%) of lymphocytic HMG-CoA reductase is required for the HMG-CoA RIs to attain effective inhibitory action in human lymphocyte lymphocyte functions in vitro. Thus the inhibitory activity of simvastatin, a lipophilic inhibitor, on sterol synthesis (HMG-CoA reductase activity) in lymphocytes was as much as 430 times more potent than that of pravastatin sodium, a hydrophilic inhibitor (IC50; 0.013 microM and 5.6 microM, respectively), and although pravastatin sodium and simvastatin at concentration levels of 10 and 0.016 microM respectively, inhibited the sterol synthesis in just over 50%, they failed to inhibit the lymphocyte functions. Significant inhibition (P < 0.01) of lymphocyte functions, including lymphocyte proliferative response to a variety of stimuli and activated natural killer-cell cytotoxicity, was demonstrated only when greater than 90% of the sterol synthesis in lymphocytes was inhibited by either simvastatin or simvastatin sodium salt at concentrations above 2 microM. This simvastatin-induced inhibition of lymphocyte functions was almost completely reversed by the addition of a 1 mM solution of mevalonate. Although simvastatin at a lower clinical blood concentration of 0.016 microM failed to inhibit either lymphocyte functions or HMG-CoA reductase activity sufficiently, at this level it caused a significant increase in cyclosporin A-induced suppression of T-cell response. These results infer that insufficient inhibition (in the 50% region) of HMG-CoA reductase activity by a low clinical blood concentration of HMG-CoA RIs, could still render the lymphocytes susceptible to immunosuppressive treatments. Pravastatin sodium on the other hand, is inactive in inhibiting lymphocyte functions in vitro, and such inactivity can be explained solely of the basis of its failure to inhibit HMG-CoA reductase activity in lymphocytes sufficiently.

Cyclosporine↗

PubMed1996

Thymus-dependent effects of a traditional Chinese medicine, ren-shen-yang-rong-tang (Japanese name; Ninjin-youei-to), in autoimmune MRI/MP-lpr/lpr mice.

Autoimmune MRL/lpr mice were i.p. treated with 200 mg/kg Ren-shen-yang-rong-tang (Japanese name: Ninjin-youei-to, NYT), a traditional Chinese herbal medicine (Japanese name: Kampo), from 8 weeks of age every 3 days before the onset of autoimmune disease Compared to age-matched control MRL/lpr mice, the serum IL-6 concentration in NYT-treated mice was decreased, their serum IFN-gamma concentration was increased, and the proliferative responses of whole and enriched CD4+ cells in their spleen and lymph nodes stimulated with ConA in vitro were restored. FACS analysis revealed that the rate of decreased CD4+CD8+ T-cell population in the thymus was decreased in MRL/lpr mice but recovered by NYT treatment. Further, adult thymectomized (ATX) MRL/lpr mice were treated with 200 mg/kg NYT similarly. NYT treatment prolonged the survival of sham-operated MRL/lpr mice and ameliorated their proteinuria but did not improve such autoimmune manifestations in ATX-MRL/lpr mice. These findings suggest that NYT plays an important role in the abrogation of autoimmune-prone T cell differentiation and that the therapeutic effect of NYT is dependent on the thymus in MRL/lpr mice.

Animals↗

PubMed1996

High serum concentration of lipoprotein(a) is a risk factor for restenosis after percutaneous transluminal coronary angioplasty in Japanese patients with single-vessel disease.

To determine the relation between the concentration of lipoprotein(a) [Lp(a)] and restenosis after percutaneous transluminal coronary angioplasty (PTCA) in Japan, we studied 80 consecutive patients with single-vessel disease who successfully underwent PTCA. All were evaluated by follow-up angiography a mean of 6.9 months after PTCA and were divided into the restenosis (30 patients) and the non-restenosis (50 patients) groups. The serum Lp(a) concentration of 29 +/- 17 mg/dl in the restenosis group was significantly higher than that of 17 +/- 14 mg/dl in the nonrestenosis group (p < 0.01). Multiple logistic regression analysis for risk factors revealed a significant correlation between restenosis and Lp(a) (p < 0.003). The serum Lp(a) concentration was positively correlated with the coronary artery percent stenosis at the time of follow-up angiography (r = 0.32, p < 0.01). High serum concentration of Lp(a) is therefore a risk factor for restenosis after PTCA in Japan.

Adult↗

PubMed1996

An increase of B cells in the tumor-bearing state has the potential to induce anti-tumor immunity.

We investigated the role of an increased amount of B cells in the tumor-bearing state. The proportion of B cells increased concomitantly with tumor development in the regional lymph nodes (LN) of BALB/c mice bearing Meth A fibrosarcoma (Meth A). Tumor development was accompanied by an increased level of IgG antibodies against Meth A. CD4+ T cells of the regional LN in the early tumor-bearing stage produced significant levels of interferon-gamma and interleukin-4 in response to in vitro stimulation with coated anti-CD3 monoclonal antibody, whereas such capacities decreased in the late tumor-bearing stage. In a tumor-neutralizing assay, the growth of Meth A was significantly suppressed by a co-inoculation with splenic B cells from BALB/c mice in the late tumor-bearing state. This suppression of Meth A growth was tumor-specific and was abolished by the in vivo depletion of either CD4+ or CD8+ T cells. These findings thus suggest that tumor development was accompanied by an increase of B cells and tumor-specific IgG production, but such kinetic changes were not the result of a preferential activation of Th2 type CD4+ T cells. Furthermore, our results indicate that the increase of B cells in the tumor-bearing state has the potential to induce anti-tumor-specific T cell immunity.

Animals↗

PubMed1996

Anti-CD4 monoclonal antibody reduces the dose of cyclophosphamide required to induce tolerance to H-2 haplotype identical skin allografts in mice.

Cyclophosphamide (CP)-induced tolerance which consists of a single i.p. injection of 200 mg/kg CP 2 days after priming with 1 x 10(8) donor spleen cells (SC), leads to long-lasting donor-specific skin allograft tolerance in H-2 compatible, multiminor antigen incompatible, murine strain combinations. In this system, the optimal dose of CP has been suggested to be 200 mg/kg, however, such a dose of CP causes strong myelosuppression. In the present study, we therefore attempted to reduce the dose of CP by administering anti-CD4 monoclonal antibody (mAb) before donor cell priming in this tolerance-inducing system. When C3H/He (C3H; H-2k, Mls-1b) mice were injected i.p. with 200 micrograms anti-CD4 mAb on day -3, 1 x 10(8) AKR/J (AKR; H-2k, Mls-1a) SC plus 3 x 10(7) bone marrow cells (BMC) i.v. on day -2 and then 100 mg/kg CP i.p. on day 0, a long-lasting donor-specific skin allograft tolerance was established; furthermore, the decreases in the number of leukocytes and the concentration of hemoglobin (Hb) in the peripheral blood were all less in the C3H mice treated with this new combined protocol than in the C3H mice injected with 200 mg/kg CP following the previous protocol. In the periphery of these tolerant mice, the number of donor-reactive V beta 6+CD4+ T cells decreased and mixed chimerism was observed on both days 14 and 80. On the other hand, in the mice injected with AKR SC, BMC plus 100 mg/kg CP without anti-CD4 mAb, the number of V beta 6+CD4+ T cells decreased on day 14, and then recovered by day 80 when the mixed chimerism disappeared. These results therefore suggest that the combined use of anti-CD4 mAb with CP can reduce the dose of CP without affecting the efficiency of inducing donor-specific tolerance, probably due to the enhancement of the destruction effect of donor-reactive T cells by CP.

Anemia↗

PubMed1996

Cyclophosphamide-induced immunological tolerance: an overview.

A cyclophosphamide (CP)-induced tolerance system in mice that primarily consists of donor cell injection followed by CP-treatment was found useful for inducing a long-lasting allo- or xeno-tolerance to various solid organs. In the cells-followed-by-CP system, the sequential mechanisms of tolerance were clarified using the specific correlation between superantigens and certain T cell receptor (TCR) V beta segments. Those include the clonal destruction of antigen-stimulated mature T cells, the peripheral clonal deletion associated with peripheral chimerism, the intrathymic clonal deletion associated with intrathymic chimerism, and the clonal anergy. The generation of suppressor T cells was another important mechanism of tolerance in the late stage. Special care was taken to overcome the " hard" barriers of allo- or xeno-combinations by reducing the "split tolerance" produced through the clonal destruction mechanism. For this purpose, the tolerogen, antimitotic drugs, their doses, timing, route of administration, combined immunosuppressants, and supportive treatment were all crucial for successful induction of a long-lasting skin tolerance. This system may be applicable to human transplantation.

Animals↗

PubMed1996

Expression of activation-related molecules on regional lymph node lymphocytes in human lung cancer.

Using two- and three-color flow cytometry, we investigated the surface makers of regional lymph node lymphocytes (RLNL) in 54 patients with primary lung cancer in order to determine whether or not RLNL are in an activation state when compared with the corresponding peripheral blood lymphocytes (PBL) for the purpose of clarifying the characteristics of RLNL. RLNL showed a cell composition that was different from the corresponding PBL with a high proportion of CD3+ cells, CD4+ cells and CD20+ (B) cells as well as a low proportion of CD8+ cells and CD16+ (NK) cells. RLNL also contained a significantly higher proportion of CD45RO+ T cells and a lower proportion of CD45RA+ T cells in comparison to the corresponding PBL. Furthermore, we explored the activation-related molecules such as the interleukin-2 receptor (IL-2R) alpha chain, the IL-2R beta chain, HLA-DR and leukocyte function-associated antigen 1 (LFA-1) on CD4+ and CD8+ cells. The data showed that the expression of CD45RO, the IL-2R alpha chain, HLA-DR on CD4+ cells, and those of CD45RO and HLA-DR on CD8+ cells were significantly higher in RLNL than in PBL. On the other hand, PBL showed a higher expression of the IL-2R beta chain and LFA-1 only on CD8+ cells, which are thought to include CD8+ NK cells. When these activation related molecules were analyzed on CD45RO+ T cells, which are thought to be memory T cells, then the expression of the IL-2R alpha chain, HLA-DR on CD4+CD45RO+ cells and HLA-DR on CD8+CD45RO+ cells were significantly higher in RLNL than in PBL. Lastly, we analyzed the surface molecules according to such clinical factors as metastasis to the lymph nodes and the stage of lung cancer. Interestingly, RLNL with lymph node metastasis showed an increase in the percentage of CD20+ cells and a decrease in the percentage of CD4+ cells in comparison to those with benign lung disease, while these differences were not observed in PBL. The expression of ++CD45RO and LFA-1 on CD4+ and LFA-1 on CD8+ cells on RLNL in stage I + II is significantly higher in comparison with benign lung disease. Furthermore, RLNL in stage III + IV revealed the reduced expression of CD45RO, HLA-DR and LFA-1 on both CD4+ and CD8+ cells compared with those in stage I + II. These results thus demonstrated that RLNL were in a more activated state, particularly in stages I + II, than PBL. Whether these activation states in RLNL are directed against autologous tumor cells or not can hopefully be elucidated after the completion of further ongoing studies.

CD4-Positive T-Lymphocytes↗