Vitamin D affects proliferation of a murine T helper cell clone

1,25-Dihydroxyvitamin D3 (1,25(OH)2D3), the biologically active form of vitamin D3, has been shown to inhibit the activation of T cell hybridomas and heterogeneous populations of mononuclear leukocytes. Because the response of various clones to 1,25(OH)2D3 may differ, we have examined the proliferative effects of the steroid on an antigen-specific cloned, nontransformed T helper cell line (D10.G4.1 [D10 cells]), and find that in contrast to these previous studies, the steroid is a potent stimulator of lectin-induced proliferation. In these experiments, D10 cells were incubated with concanavalin A and 1,25(OH)2D3, and although the lectin or steroid alone has minimal proliferative effects, their co-addition prompts up to a 50-fold increase in 3H-TdR incorporation at a concentration of 2.5 to 5 X 10(-9) M 1,25(OH)2D3, with significant mitogenesis occurring at 0.1 to 0.3 X 10(-9) M 1,25(OH)2D3. 25-Hydroxyvitamin D3 and 24,25(OH)2D3 have similar activity, but at concentrations two to three times greater than that of 1,25(OH)2D3, reflecting their relative affinities for the 1,25(OH)2D3 receptor. In addition, lectin treatment enhances 1,25(OH)2D3 receptor capacity fourfold to fivefold, an event coupled with the appearance of positive cooperativity. Although the steroid does not affect the quantity of bioassayable T cell growth factors as assessed by HT-2 cell proliferation, the expression of immunoreactive IL 2 receptors by lectin-activated D10 cells exposed to 1,25(OH)2D3 is enhanced. In contrast to its proliferative effect in the absence of IL 1, 1,25(OH)2D3 exerts biphasic effects on D10 replication when this monokine is present. Specifically, this steroid augments D10 proliferation at low concentrations of recombinant IL 1, but as the abundance of the monokine increases in the presence of 10(-10) to 10(-8) M 1,25(OH)2D3, the peak response of D10 cells to optimal IL 1 concentrations is diminished. Therefore, in this clone, 1,25(OH)2D3 presents itself as a regulator of T helper cell proliferation.     

Low-dose melphalan-induced shift in the production of a Th2-type cytokine to a Th1-type cytokine in mice bearing a large MOPC-315 tumor

The current studies demonstrate that MOPC-315 tumor cells secrete large amounts of interleukin-10 (IL-10), which contributes to the inhibitory activity of MOPC-315 culture supernatants for the in vitro generation of antitumor cytotoxicity by MOPC-315-immune spleen cells. Moreover, addition of neutralizing monoclonal anti-IL-10 antibody to the in vitro stimulation cultures of cells from the tumor infiltrated spleens of mice bearing a large MOPC-315 tumor resulted in the generation of enhanced anti-MOPC-315 cytotoxicity. In contrast, addition of monoclonal anti-IL-10 antibody to the in vitro stimulation cultures of splenic cells from mice that are in the final stages of immune-mediated tumor eradication as a consequence of low-dose melphalan (l-phenylalanine mustard; L-PAM) therapy (and whose spleens no longer contain metastatic tumor cells) did not lead to enhancement in the in vitro generation of antitumor cytotoxicity. The cessation of IL-10 secretion as a consequence of low-dose L-PAM therapy of MOPC-315 tumor bearers was found to be accompanied by the acquisition of the ability to secrete interferon (IFN) by the splenic cells. In addition, by day 2 after low-dose L-PAM therapy a drastic decrease in the amount of IL-10 secreted by the s.c. tumor nodules was noted, which preceded the accumulation of tumor-infiltrating lymphocytes capable of secreting IFN. Thus, low-dose L-PAM therapy of mice bearing a large MOPC-315 tumor leads to a shift in cytokine production from a Th2-type cytokine to a Th1-type cytokine, and it is conceivable that this shift in cytokine production plays an important role in the low-dose L-PAM-induced acquisition of antitumor immunity by hitherto immunosuppressed mice bearing a large MOPC-315 tumor.Supported by research grant IM-435 from the American Cancer Society and CA54413 from the National Cancer InstituteIn partial fulfillment of the requirements for the Doctor of Philosophy DegreeRecipient of career development award CA-01350 from the National Cancer Institute     

Testosterone and estrogen differently effect Th1 and Th2 cytokine release following trauma-haemorrhage.

The object of the study was to determine whether male and female sex steroids produce divergent effects on Th1 and Th2 cytokine release following trauma-haemorrhage. Recent studies indicate that androgens are responsible for the depressed splenocyte Th1 cytokine release in males following trauma-haemorrhage. In contrast, female mice maintain their Th1 cytokine release capacity following trauma-haemorrhage. Nonetheless, the effect of male and female sex steroids on Th1 and Th2 cytokine release following trauma-haemorrhage remains unknown. Male C3H/HeN mice were castrated and treated with pellets containing either vehicle, 5alpha-dihydrotestosterone (DHT), 17beta-estradiol (estradiol), or a combination of both steroid hormones, for 14 days prior to soft-tissue trauma (i.e. laparotomy) and haemorrhagic shock (35+/-5 mmHg for 90 min followed by adequate fluid resuscitation) or sham operation. Untreated male and female mice, as well as DHT treated female mice, served as control groups. Twenty-four hours later the animals were sacrificed, plasma obtained and splenocytes harvested. Plasma DHT and estradiol levels in treated animals were comparable with intact male and female mice, respectively. A significant depression of splenocyte Th1 cytokines, i.e. IL-2, IFN-gamma, was observed in DHT treated castrated animals, DHT treated females, and untreated males following trauma-haemorrhage, as opposed to maintained Th1 cytokine release in estradiol treated and estradiol/DHT treated castrated animals and females. The release of the anti-inflammatory cytokine IL-10 was markedly increased in DHT treated mice and males subjected to trauma-haemorrhage compared to shams, but decreased in estrogen treated mice and females under such conditions. These results suggest that male and female sex steroids differentially affect the release of Th1 and Th2 cytokines following trauma-haemorrhage and should be further studied for their potential to modulate splenocyte function in trauma victims.     

Glucose-regulated protein 94/glycoprotein 96 elicits bystander activation of CD4+ T cell Th1 cytokine production in vivo

Glucose-regulated protein 94 (GRP94/gp96), the endoplasmic reticulum heat shock protein 90 paralog, elicits both innate and adaptive immune responses. Regarding the former, GRP94/gp96 stimulates APC cytokine expression and dendritic cell maturation. The adaptive component of GRP94/gp96 function reflects a proposed peptide-binding activity and, consequently, a role for native GRP94/gp96-peptide complexes in cross-presentation. It is by this mechanism that tumor-derived GRP94/gp96 is thought to suppress tumor growth and metastasis. Recent data have demonstrated that GRP94/gp96-elicited innate immune responses can be sufficient to suppress tumor growth and metastasis. However, the immunological processes activated in response to tumor Ag-negative sources of GRP94/gp96 are currently unknown. We have examined the in vivo immunological response to nontumor sources of GRP94/gp96 and report that administration of syngeneic GRP94/gp96- or GRP94/gp96-N-terminal domain-secreting KBALB fibroblasts to BALB/c mice stimulates CD11b(+) and CD11c(+) APC function and promotes bystander activation of CD4(+) T cell Th1 cytokine production. Only modest activation of CD8(+) T cell or NK cell cytolytic function was observed. The GRP94/gp96-dependent induction of CD4(+) T cell cytokine production was markedly inhibited by carrageenan, indicating an essential role for APC in this response. These results identify the bystander activation of CD4(+) T lymphocytes as a previously unappreciated immunological consequence of GRP94/gp96 administration and demonstrate that GRP94/gp96-elicited alterations in the in vivo cytokine environment influence the development of CD4(+) T cell effector functions, independently of its proposed function as a peptide chaperone.     

Effect of T helper 1 (Th1)/Th2 cytokine on chemokine-induced dendritic cell functions

Effects of T helper 2 (Th2) and Th1 cytokines, interleukin (IL)-4, and interferon (IFN)-gamma, respectively, on chemokine-induced DC migration and endocytosis are not well understood. We investigated herein the effects of these cytokines on chemokine-induced functions of murine myeloid DCs. As expected, immature DCs markedly migrated to CCL3 but not CCL19, while mature DCs showed vigorous migration in response to CCL19 but not CCL3. Both IL-4 and IFN-gamma significantly decreased CCL3-induced migration of immature DCs. In contrast, these cytokines exerted no significant effects on CCL19-induced migration of mature DCs. Of note, both IL-4 and IFN-gamma markedly enhanced CCL3-induced endocytosis of immature DCs. The messenger RNA level of CCR5, a CCL3 receptor, in immature DCs was slightly increased by IL-4 or IFN-gamma treatment. These results demonstrate that these Th1/Th2 cytokines can act to either inhibit or enhance chemokine-mediated DC functions, and may play a role in increasing antigen uptake by immature DCs at inflammatory sites.     

The attachment (G) glycoprotein of respiratory syncytial virus contains a single immunodominant epitope that elicits both Th1 and Th2 CD4+ T cell responses

BALB/c mice immunized with a vaccinia virus expressing the attachment (G) glycoprotein of respiratory syncytial virus (RSV) develop a virus-specific CD4(+) T cell response that consists of a mixture of Th1 and Th2 CD4(+) T cells following intranasal infection with live RSV. Recent work has shown that both Th1 and Th2 CD4(+) T cells are elicited to a single region comprising aa 183-197 of the G protein. To more precisely define the CD4(+) T cell epitope(s) contained within this region, we created a panel of amino- and carboxyl-terminal truncated as well as single alanine-substituted peptides spanning aa 183-197. These peptides were used to examine the ex vivo cytokine response of memory effector CD4(+) T cells infiltrating the lungs of G-primed RSV-infected mice. Analysis of lung-derived memory effector CD4(+) T cells using intracellular cytokine staining and/or ELISA of effector T cell culture supernatants revealed a single I-E(d)-restricted CD4(+) T cell epitope with a core sequence mapping to aa 185-193. In addition, we examined the T cell repertoire of the RSV G peptide-specific CD4(+) T cells and show that the CD4(+) T cells directed to this single immunodominant G epitope use a restricted range of TCR Vss genes and predominantly express Vss14 TCR.     

Effect of suplatast tosilate (IPD-1151T) on cytokine production by allergen-specific human Th1 and Th2 cell lines.

Suplatast tosilate (IPD-1151T) is an antiallergic agent that suppresses airway eosinophil infiltration in asthma. We investigated the effects of IPD-1151T on proliferative response and cytokine production by human antigen-specific T cell lines. Purified protein derivatives (PPD)-specific T helper 1 (Th1) cell lines and Dermatophagoides farinae (Der f)-specific T helper 2 (Th2) cell lines were established from patients with asthma sensitized with house dust mite. Stimulation of PPD-specific and Der f-specific T cell lines with relevant antigens resulted in production of mostly interferon (IFN)-gamma and of interleukin (IL)-4 and IL-5, respectively. IPD-1151T did not inhibit the proliferative responses of either the Th1 or Th2 cell line to antigens. Although IPD-1151T did not inhibit IFN-gamma production by PPD-specific Th1 cell lines, it did inhibit IL-4 and IL-5 production by antigen-stimulated Der f-specific Th2 cell lines in a dose-dependent manner. IPD-1151T directly inhibited cytokine production by Der f-specific Th2 cell lines stimulated with immobilized anti-CD3 antibodies. Although IPD-1151T did not inhibit the clonal expansion of memory T cells among PBMCs into PPD-specific Th1 and Th2 cell lines, it did inhibit IL-4 and IL-5 production by Der f-specific Th2 cell lines but not IFN-gamma production by PPD-specific Th1 cell lines. These results suggest that IPD-1151T selectively inhibits Th2-type cytokine production.     

Responsiveness of naive CD4 T cells to polarizing cytokine determines the ratio of Th1 and Th2 cell differentiation

The intrinsic features of naive CD4 T cells that affect their ability to respond to polarizing signals for Th cell differentiation are not well understood. In this study, we show that naive CD4 T cells from mice transgenic for the Hlx gene expressed lower levels of IL-4Ralpha. The down-regulation of IL-4Ralpha diminished IL-4 signaling and the Th2 response and enhanced the Th1 response under suboptimal polarizing conditions. In nontransgenic CD4 T cells, blocking IL-4Ralpha with Abs had the same effect in an Ab dose-dependent manner. Conversely, Hlx haploinsufficiency caused higher expression of IL-4Ralpha to favor Th2 cell differentiation. Thus, the IL-4Ralpha level on naive CD4 T cells is genetically controlled by Hlx and determines the ratio of Th1 and Th2 cell differentiation.     

Interleukin 2 and concanavalin A stimulate interferon-gamma production in a murine cytolytic T cell clone by different pathways

We identified a variant murine cytolytic T lymphocyte (CTL) clone which, in contrast to the parent clone and all other murine T cell populations tested, was found to have acquired spontaneously the ability to produce interferon-gamma (IFN-gamma) in response to recombinant interleukin 2 (rIL-2). IFN-gamma production in response to concanavalin A (Con A), which was characteristic of all T cell populations tested, was preserved in this variant. The IFN produced by the variant in response to either stimulus was active in both a macrophage-activating factor assay and an anti-viral assay. Both activities induced by either stimulus could be blocked by monoclonal anti-IFN-gamma antibodies. Upon Northern blot analysis using an IFN-gamma-specific cDNA probe, the IFN-gamma RNA isolated from variant cells stimulated with Con A or IL-2 were found to migrate equivalently. The unusual pattern of responsiveness in this variant CTL was exploited to compare the mechanisms involved in induction of IFN-gamma production by Con A or IL-2. Striking differences were observed. Unlike IFN-gamma production induced by Con A, IFN-gamma production induced by IL-2 was not accompanied by an elevation of intracellular Ca2+ levels, did not require physiologic extracellular Ca2+ levels, and was not inhibited by the immunosuppressive agent cyclosporin A. Thus, in this variant CTL clone, conditions that have ordinarily been associated in an obligate manner with lymphokine gene expression were found instead to be related to the specific mode of stimulation.     

IL-10 augments antibody production in in vitro immunized lymphocytes by inducing a Th2-type response and B cell maturation

An in vitro immunization (IVI) protocol enables antigen specific antibody production from L-Leucyl-L-Leucine methyl ester (LLME)-treated human peripheral blood lymphocytes (PBL) upon antigen stimulation in the presence of IL-2, IL-4, and muramyl dipeptide. In the course of our studies, we have found that IL-10 added at the antigen sensitization significantly augmented antibody production level from the LLME-treated PBL. In the present study, we tried to demonstrate the role of IL-10 in the augmentation of antibody production in an IVI protocol by clarifying the cytokine expression profiles in CD4(+) and CD8(+) T cells. The results showed that IL-10 skewed the Th1/Th2 balance to Th2-type responses by suppressing Th1-type cytokine production and augmenting Th2-type cytokine production in CD4(+) and CD8(+) T cells, as well as in CD19(+) B cells. Furthermore, IL-10 augmented the expression of CD38, an antigen marker of plasma cells, on B cells, which clearly indicates that IL-10 promoted differentiation and maturation of B cells in an IVI protocol. These results indicate that IL-10 plays an important role in setting the cellular milieu to produce antibodies in an IVI protocol.     

Characteristics of the porcine kidney cell line IB-RS-2 clone D10 (IB-RS-2 D10) which is free of hog cholera virus

Summary A Brazilian stock of clone C17 of the IB-RS-2 porcine kidney cell line which was contaminated with hog cholera virus (HCV) was cloned. One clone designated IB-RS-2 D10 was determined to be free of HCV, 20 other viruses, andMycoplasma. IB-RS-2 D10 cells possessed the same viral susceptibility pattern as the contaminated parent cells to the viruses of foot-and-mouth disease, swine vesicular disease, vesicular exanthema of swine, transmissible gastroenteritis, and several other viruses. The IB-RS-2 D10 cells had a median chromosome count of 34, were morphologically epithelioid cells, and were resistant to HCV infection. Freedom from HCV affords advantages for vaccine production and avoids laboratory contamination. Mention of a trademark, propriety product, or source does not constitute a guarantee or warranty of the product by the USDA, and does not imply its approval to the exclusion of other products that may be suitable.     

Chronic morphine treatment promotes specific Th2 cytokine production by murine T cells in vitro via a Fas/Fas ligand-dependent mechanism

Improper homeostasis of Th1 and Th2 cell differentiation can promote pathological immune responses such as autoimmunity and asthma. A number of factors govern the development of these cells including TCR ligation, costimulation, death effector expression, and activation-induced cell death (AICD). Although chronic morphine administration has been shown to selectively promote Th2 development in unpurified T cell populations, the direct effects of chronic morphine on Th cell skewing and cytokine production by CD4(+) T cells have not been elucidated. We previously showed that morphine enhances Fas death receptor expression in a T cell hybridoma and human PBL. In addition, we have demonstrated a role for Fas, Fas ligand (FasL), and TRAIL in promoting Th2 development via killing of Th1 cells. Therefore, we analyzed whether the ability of morphine to affect Th2 cytokine production was mediated by regulation of Fas, FasL, and TRAIL expression and AICD directly in purified Th cells. We found that morphine significantly promoted IL-4 and IL-13 production but did not alter IL-5 or IFN-gamma. Furthermore, morphine enhanced the mRNA expression of Fas, FasL and TRAIL and promoted Fas-mediated AICD of CD4(+) T cells. Additionally, blockade of Fas/FasL interaction by anti-FasL inhibited the morphine-induced production of IL-4 and IL-13 and AICD of CD4(+) T cells. These results suggest that morphine preferentially enhances Th2 cell differentiation via killing of Th1 cells in a Fas/FasL-dependent manner.     

Differential monocyte chemoattractant protein-1 and chemokine receptor 2 expression by murine lung fibroblasts derived from Th1- and Th2-type pulmonary granuloma models.

Recent studies suggest that monocyte chemoattractant protein-1 (MCP-1) is involved in fibrosis through the regulation of profibrotic cytokine generation and matrix deposition. Changes in MCP-1, C-C chemokine receptor 2 (CCR2), procollagen I and III, and TGF beta were examined in fibroblasts cultured from normal lung and from nonfibrotic (i.e., Th1-type) and fibrotic (i.e., Th2-type) pulmonary granulomas. Th2-type fibroblasts generated 2-fold more MCP-1 than similar numbers of Th1-type or normal fibroblasts after 24 h in culture. Unlike normal and Th1-type fibroblasts, Th2-type fibroblasts displayed CCR2 mRNA at 24 h after IL-4 treatment. By flow cytometry, CCR2 was present on 40% of untreated Th2-type fibroblasts, whereas CCR2 was present on <20% of normal and Th1-type fibroblasts after similar treatment. IL-4 increased the number of normal fibroblasts with cell-surface CCR2 but IFN-gamma-treatment of normal and Th2-type fibroblasts significantly decreased the numbers of CCR2-positive cells in both populations. Western blot analysis showed that total CCR2 protein expression was markedly increased in untreated Th2-type fibroblasts compared with normal and Th1-type fibroblasts. IL-4 treatment enhanced CCR2 protein in Th1- and Th2-type fibroblasts whereas IFN-gamma treatment augmented CCR2 protein in normal and Th1-type fibroblasts. All three fibroblast populations exhibited MCP-1-dependent TGF-beta synthesis, but only normal and Th2-type fibroblasts showed a MCP-1 requirement for procollagen mRNA expression. Taken together, these findings suggest that lung fibroblasts are altered in their expression of MCP-1, TGF-beta, CCR2, and procollagen following their participation in pulmonary inflammatory processes, and these changes may be important during fibrosis.     

Preproenkephalin is a Th2 cytokine but is not required for Th2 differentiation in vitro.

Preproenkephalin (PPNK) mRNA expression has been detected in many cells of the immune system, including monocytes and lymphocytes. In the present paper, the expression of PPNK mRNA in purified CD4+ Th1 and Th2 lymphocyte subpopulations is investigated and correlated with the presence of the opioid neuropeptides leu- and met-enkephalin. We found that PPNK mRNA and met-enkephalin were present at higher levels in the Th2 cultures compared with the Th1 cultures. Lymphocytes from PPNK-deficient mice were then used to look at the role of PPNK in Th2 lymphocyte differentiation. Lymphocytes from these mice could be driven into a Th2 phenotype, suggesting that cultures containing IL-4 do not require PPNK for Th2 differentiation.     

Co-expression of IL-18 binding protein and IL-4 regulates Th1/Th2 cytokine response in murine collagen-induced arthritis

We constructed a recombinant adenoviral vector containing a murine interleukin （IL）-18 binding protein （mlL-18BP） and murine IL-4 （mIL-4） fusion gene （AdmIL-18BP/mIL.4） and used a gene therapy approach to investigate the role of IL-18BP and IL-4 in modulating the T-helperl and T-helper2 （Th1/Th2） balance in mice with collagen-induced arthritis （CIA）. Mice with CIA were intra-articularly injected with 107 pfu/6 μl ofeitherAdmIL.18BP/mIL-4, or a controladenovirus, or with the control vehicle （phosphate-buffered saline）. After intra-articular gene therapy with AdmIL-18BP/mIL-4, the serum levels of tumor necrosis factor-α （TNF-α）, T-interferon （IFN-γ）, IL-4, IL-10, and IL-18 in mice with CIA were assessed by ELISA. IFN-T-expressing and IL-4-expressing CD4^＋ T cells from mice splenocytes were monitored by flow cytometry. Mice with CIA at weeks 1, 2, and 4 after intraarticular injection of AdmIL-18BP/mIL-4 showed significantly increased serum concentrations of IL-4 and IL-10 （P〈0.01 at all time points） but greatly decreased serum concentrations ofIFN-γ, TNF-α and IL-β （P〈0.01 at all time points ） compared to both the con trol adenovirus and phospha tebuffered saline control groups. The percentage of LFN-γ- producing CD4^＋ T cells was significantly decreased in response to local AdmIL-18BP/mIL-4 treatment. The percentage of IL-4-producing CD4^＋ T cells increased significantly at 1 week after local injection of AdmIL-18BP/ mIL-4 then returned to normal by week 4. These data indicated the significant modifying effects on the Th1/Th2 imbalance in murine CIA produced by local overexpression of IL-18BP and IL-4. Combination treatment with IL-18BP and IL-4 is a promising potential therapy for rheumatoid arthritis.     

Th2与ILC2细胞在哮喘模型中的数量及产生细胞因子的比较研究

目的比较过敏原依赖和非依赖性哮喘模型中2型辅助性T细胞(Th2 cell)和固有淋巴样2型细胞(type 2innate lymphoid cell,ILC2)的功能。方法滴鼻法制备过敏原卵清蛋白(ovalbumin,OVA)和上皮源性细胞因子(IL-25、IL-33)诱导的亚急性和慢性哮喘小鼠模型。收集小鼠肺泡灌洗液(bronchoalvelar lavage fluid,BALF)进行细胞计数;取左肺进行石蜡包埋、切片和HE染色;右肺行流式细胞术,以分析在不同时间点各组小鼠Th2细胞和ILC2细胞数目和占肺组织总细胞比例,并对Th2型细胞因子的来源进行分析。结果与生理盐水组相比,各实验组BALF中总细胞数明显增加; HE染色可见OVA、IL-25和IL-33均可诱导哮喘典型病理学改变;各实验组肺组织中Th2细胞与ILC2细胞均明显上升,数量上以Th2细胞为主,两者均可产生Th2型细胞因子IL-5和IL-13,且以Th2细胞为主。而在致哮喘样改变、促进Th2细胞和ILC2细胞在小鼠肺部聚集等方面,以IL-33的效应最强。结论在过敏原OVA和非过敏原IL-25、IL-33诱导的哮喘模型中,Th2型细胞因子主要来源均为Th2细胞,提示Th2细胞在哮喘的发生、发展中起到主要作用。IL-33可能是过敏性和非过敏性哮喘患者个体化治疗的潜在靶点。     

TGF-beta and IL-10 regulation of IFN-gamma produced in Th2-type schistosome granulomas requires IL-12

Interleukin-10 (IL-10) and transforming growth factor-beta (TGF-beta) regulate CD4+ T cell interferon-gamma (IFN-gamma) secretion in schistosome granulomas. The role of IL-12 was determined using C57BL/6 and CBA mice. C57BL/6 IL-4-/- granuloma cells were stimulated to produce IFN-gamma when cultured with IL-10 or TGF-beta neutralizing monoclonal antibody. In comparison, C57BL/6 wild-type (WT) control granuloma cells produced less IFN-gamma. IL-12, IL-18, and soluble egg antigen stimulated IFN-gamma release from C57BL/6 IL-4-/- and WT mice. IFN-gamma production in C57 IL-4-/- and WT granulomas was IL-12 dependent, because IL-12 blockade partly abrogated IFN-gamma secretion after stimulation. All granuloma cells released IL-12 (p70 and p40), and IL-12 production remained constant after anti-TGF-beta, anti-IL-10, recombinant IL-18, or antigen stimulation. C57 WT and IL-4-/- mouse granuloma cells expressed IL-12 receptor (IL-12R) beta1-subunit mRNA but little beta2 mRNA. TGF-beta or IL-10 blockade did not influence beta1 or beta2 mRNA expression. CBA mouse dispersed granuloma cells released no measurable IFN-gamma, produced IL-12 p70 and little p40, and expressed IL-12R beta2 and little beta1 mRNA. In T helper 2 (Th2) granulomas of C57BL/6 WT and IL-4-/- mice, cells produce IL-12 (for IFN-gamma production) and IL-10 and TGF-beta modulate IFN-gamma secretion via mechanisms independent of IL-12 and IL-12R mRNA regulation. We found substantial differences in control of granuloma IFN-gamma production and IL-12 circuitry in C57BL/6 and CBA mice.     

Two types of murine helper T cell clone. II. Delayed-type hypersensitivity is mediated by TH1 clones

We have previously shown that at least two types of Lyt-1+, Lyt-2-, L3T4+ helper T cell clones can be distinguished in vitro by different patterns of lymphokine secretion and by different forms of B cell help. Evidence is presented here to show that one type of helper T cell clone (TH1) causes delayed-type hypersensitivity (DTH) when injected with the appropriate antigen into the footpads of naive mice. The antigen-specific, major histocompatability complex (MHC)-restricted footpad swelling reaction peaked at approximately 24 hr. Footpad swelling was induced by all TH1 clones tested so far, including clones specific for soluble, particulate, or allogeneic antigens. In contrast, local transfer of TH2 cells and antigen did not produce a DTH reaction, even when supplemented with syngeneic spleen accessory cells. Similarly, local transfer of an alloreactive cytotoxic T lymphocyte clone into appropriate recipients did not produce DTH. The requirements for the DTH reaction induced by TH1 cells were investigated further by using TH1 clones with dual specificity for both foreign antigens and M1s antigens. Although these clones responded in vitro to either antigen + syngeneic presenting cells, or M1s disparate spleen cells, they responded in vivo only to antigen + MHC and did not cause footpad swelling in an M1s-disparate mouse in the absence of antigen. Moreover, in vitro preactivation of TH1 or TH2 cells with the lectin concanavalin A was insufficient to induce DTH reactions upon subsequent injection into footpads. From these results, we conclude that the lack of DTH given by TH2 clones in vivo could be due to the inability of the TH2 cells to produce the correct mediators of DTH, or to a lack of stimulation of TH2 clones in the footpad environment.