Boosting antitumor responses of T lymphocytes infiltrating human prostate cancers

Immunotherapy may provide valid alternative therapy for patients with hormone-refractory metastatic prostate cancer. However, if the tumor environment exerts a suppressive action on antigen-specific tumor-infiltrating lymphocytes (TIL), immunotherapy will achieve little, if any, success. In this study, we analyzed the modulation of TIL responses by the tumor environment using collagen gel matrix–supported organ cultures of human prostate carcinomas. Our results indicate that human prostatic adenocarcinomas are infiltrated by terminally differentiated cytotoxic T lymphocytes that are, however, in an unresponsive status. We demonstrate the presence of high levels of nitrotyrosines in prostatic TIL, suggesting a local production of peroxynitrites. By inhibiting the activity of arginase and nitric oxide synthase, key enzymes of L-arginine metabolism that are highly expressed in malignant but not in normal prostates, reduced tyrosine nitration and restoration of TIL responsiveness to tumor were achieved. The metabolic control exerted by the tumor on TIL function was confirmed in a transgenic mouse prostate model, which exhibits similarities with human prostate cancer. These results identify a novel and dominant mechanism by which cancers induce immunosuppression in situ and suggest novel strategies for tumor immunotherapy.

Homing and memory patterns of human γδ T cells in physiopathological situations

Vgamma9Vdelta2 are a heterogeneous population of T cells and comprise distinct naive, memory and effector populations that can be distinguished on the basis of surface marker expression and effector functions. We review here these recently studied features of Vgamma9Vdelta2 T lymphocyte biology and the roles they play in infectious and autoimmune diseases.

CCR6 expression defines regulatory effector/memory-like cells within the CD25(+)CD4+ T-cell subset

Regulatory CD25(+)CD4+ T cells (Treg cells) are a central element of peripheral tolerance. Little is known, however, about phenotypic and functional characteristics of these cells with regard to memory. In this study we show that the chemokine receptor CCR6 is expressed on a distinct subset of mouse Treg cells. Similar to their CD25- counterparts, CCR6+ Treg cells exhibit markers of activation, memory, and expansion that are indicative for an effector-memory function. They are memory-like cells, generated in vivo from CCR6(-)CD25+ T cells after the encounter of antigen. As conventional CD25- effector-memory T cells, they have a high turnover rate and, in contrast to CCR6- Treg cells, they respond rapidly to restimulation in vitro with up-regulation of interleukin 10. CCR6+ Treg cells are enriched in the peripheral blood and accumulate in the central nervous system after induction of experimental autoimmune encephalomyelitis (EAE). This subset therefore seems to represent a population of regulatory effector-memory T cells (T(REM)), destined to control potentially destructive immune responses directly in inflamed tissues. Importantly, these cells are also present in humans. Here the expression of CCR6 fully cosegregates with CD45RO, an established marker of human memory T cells.

Gangliosides act as onconeural antigens in paraneoplastic neuropathies

We describe two patients with progressive neuropathy and lung cancer in whom gangliosides (GS) may represent the oncoantigens. Patient 1 had motor neuropathy, high titers of IgG1 and IgG3 to GD1a and GM1, and expansion of circulating gamma-delta T lymphocytes, a T-cell subset responding to glycolipids. Patient 2 presented with Miller-Fisher-like syndrome and IgG3 activity to disialo-GS. In both cases, decreased autoimmune responses and stabilization of neuropathy were accomplished by tumor treatment. By immunohistochemistry, patient 1's IgG bound to his own tumor and to structures of normal nervous system expressing GD1a or GM1. Infiltration of IgG in the same neural structures was found at his autopsy. Regarding cellular immunity, the proportion of gamma-delta T lymphocytes infiltrating carcinoma from patient 1 was significantly higher than in neoplastic controls. These results indicate that GS may represent onconeural antigens in paraneoplastic neuropathy (PNN); their expression on neoplastic tissue may elicit autoimmune responses, which also target neural structures.

FcγRIII discriminates between 2 subsets of Vγ9Vδ2 effector cells with different responses and activation pathways

Upon recognition of nonpeptidic phosphoantigens, human Vδ2 T lymphocytes enter a lineage differentiation pattern that determines the generation of memory cells with a range of effector functions. Here, we show that within the effector memory Vδ2 population, 2 distinct and complementary subsets with regard to phenotype, mode of activation, and type of responses can be identified: Vδ2 TEMh cells, which express high levels of chemokine receptors, but low levels of perforin and of natural killer receptors (NKRs) and which produce large amounts of interferon γ (IFN-γ) and tumor necrosis factor α (TNF-α) in response to T-cell receptor (TCR)–specific stimulation by phosphoantigens; and Vδ2TEMRA cells, which constitutively express several NKRs, high amounts of perforin, but low levels of chemokine receptors and of IFN-γ. These NK-like cells are refractory to phosphoantigen but respond to activation via FcγRIII (CD16) and are highly active against tumoral target cells. Thus, circulating Vδ2T lymphocytes comprise 2 functionally diverse subsets of effector memory cells that may be discriminated on the basis of CD16 expression.

Stem cell-mediated muscle regeneration is enhanced by local isoform of insulin-like growth factor 1

We investigated the mechanism whereby expression of a transgene encoding a locally acting isoform of insulin-like growth factor 1 (mIGF-1) enhances repair of skeletal muscle damage. Increased recruitment of proliferating bone marrow cells to injured MLC/mIgf-1 transgenic muscles was accompanied by elevated bone marrow stem cell production in response to distal trauma. Regenerating MLC/mIgf-1 transgenic muscles contained increased cell populations expressing stem cell markers, exhibited accelerated myogenic differentiation, expressed markers of regeneration and readily converted cocultured bone marrow to muscle. These data implicate mIGF-1 as a powerful enhancer of the regeneration response, mediating the recruitment of bone marrow cells to sites of tissue damage and augmenting local repair mechanisms.

Identification and enrichment of spermatogonial stem cells displaying side-population phenotype in immature mouse testis

In mammals, spermatogenesis is maintained by spermatogonial stem cells (SSC). In their niche, SSC divide to self-maintain and to produce a transit-amplifying population that eventually enters the meiotic cycle to give rise to spermatozoa. The low number of SSC and the lack of specific markers hinder their isolation and enrichment. Stem cells in several adult tissues can be identified by using their verapamil-sensitive Hoechst dye-effluxing properties, which define the characteristic "side population" (SP). Here we show, by multicolor flow cytometric analysis, that immature mouse testis contains a "side-population" (T-SP), which is Sca-1pos, Ep-CAMpos, EE2 pos, alpha6-integrin pos, and alpha(v)-integrin neg. A 13-fold enrichment in SSC activity was observed when sorted T-SP cells from ROSA 26 mice were transplanted in busulfan-treated mouse testis. Whereas an incomplete range of spermatogenic stages was encountered two months after transplantation of unsorted testicular cells, the transplantation of T-SP cells generated all associations of mouse germ cells representing the full range of spermatogenic stages. These data suggest that Hoechst staining and cell sorting might provide a novel approach to SSC enrichment in mammals.

Allogeneic hematopoietic stem cell transplantation in a patient affected by large granular lymphocyte leukemia and multiple sclerosis

We describe a 57-year-old man, affected by large granular lymphocyte (LGL) leukemia and concomitant primary progressive multiple sclerosis (MS), treated with allogeneic hematopoietic stem cell transplantation (HSCT) from an HLA-identical sibling. The patient was conditioned with fludarabine, busulphan, and cyclophosphamide. Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporine and short-term methotrexate. At 3 years follow-up, the patient is in complete remission of LGL with a marked improvement in neurological conditions. This is the first case of allogeneic HSCT in a patient with LGL leukemia and concomitant primary progressive MS. Allogeneic HSCT, performed in our patient to cure the lymphoproliferative disorder, improved the clinical course of MS.

CD8+ T cells from patients with acute multiple sclerosis display selective increase of adhesiveness in brain venules: a critical role for P-selectin glycoprotein ligand-1

Multiple sclerosis (MS) is considered an autoimmune inflammatory disease of the central nervous system. Under physiologic conditions, we compared the adhesiveness of CD4+ and CD8+ lymphocytes from nontreated patients with acute, relapsing-remitting multiple sclerosis (RRMS) and from healthy donors. We show that in patients with RRMS CD8+, but not with RRMS CD4+, T cells display increased rolling and arrest in inflamed murine brain venules. Moreover, CD8+, but not CD4+, lymphocytes from MS patients show increased rolling on P-selectin in vitro. Anti-P-selectin glycoprotein ligand-1 (PSGL-1) antibodies dramatically block the recruitment of CD8+ cells in brain vessels of patients with MS, suggesting that PSGL-1 represents a novel pharmaceutical target that may be exploited to block the selective entrance of CD8+ cells during early inflammation. Vascular cell adhesion molecule-1 (VCAM-1), but not PSGL-1, is critical for the adhesion of CD4+ cells in MS patients, highlighting a fundamental dichotomy in the mechanisms governing the recruitment of lymphocyte subsets in RRMS. Importantly, 7-color fluorescence-activated cell sorter (FACS) analysis, together with functional data, indicates that a large fraction of CD8+ cells from MS patients display the characteristics of memory-effector phenotype. In conclusion, our results show that CD8+, but not CD4+, T cells from patients with RRMS in the acute phase of the disease display increased ability to be recruited in inflamed brain venules.

Phenotypic and functional analysis of T cells homing into the CSF of subjects with inflammatory diseases of the CNS

The recruitment of lymphocytes across the blood brain barrier (BBB) is mediated by adhesion molecules and chemokines. The expression of activation markers and of chemokine receptors on T cells homing to the nervous system (NS) may help define their functional state. In the cerebrospinal fluid (CSF) of subjects with inflammatory neurological diseases (IND), including multiple sclerosis, we observed an increased number of T cells coexpressing CXCR3 and CCR5 as well as T cells with a CD45RO+ CCR7+ CD27+ memory phenotype. A subset of CCR7+ T cells coexpressed CXCR3 and CCR5. We also detected an increased number of interferon-gamma-producing T cells in the CSF compared with peripheral blood, mostly but not exclusively in the CD45RO+ CCR7- CD27- compartment. T helper 1 (Th1) clones, established from the CSF of individuals with IND and from a healthy subject, similarly migrated to CXCL10, CXCL12, and CCL5. CXCL10, CXCL12, and CCL19 were increased in the CSF of individuals with neuroinflammation. These findings suggest that CSF is enriched in Th1-polarized memory T cells capable of differentiating into effector cells upon antigen encounter. These cells are recruited into the CSF by inducible chemokines. Thus, CSF represents a transitional station for T cells trafficking to and from the NS.

Involvement of classical and novel protein kinase C isoforms in the response of human V gamma 9V delta 2 T cells to phosphate antigens

Human gammadelta T cells expressing the Vgamma9Vdelta2 gene segments are activated polyclonally by phosphoantigens found on a wide variety of pathogenic organisms. After ligand exposure, Vgamma9Vdelta2 T cells proliferate and rapidly secrete large amounts of cytokines and chemokines that contribute to the innate immune response to these pathogens. Neither APCs nor costimulatory molecules are required. In this study we examined whether these phosphoantigens activate protein kinase Ctheta (PKCtheta). This novel PKC isoform is essential for Ag signaling through the alphabeta TCR in a costimulation-dependent fashion. The results showed that isopentenyl pyrophosphate (IPP), a soluble phospholigand released by mycobacteria, led to the rapid and persistent activation of PKCtheta in gammadelta T cells, as determined by evidence of translocation and phosphorylation. In contrast, no ligand-dependent response was detected for PKCalpha/beta or PKCdelta. Using the inhibitors Gö6976 and rottlerin, a role for both conventional and novel PKC isoforms in IPP-induced proliferation, CD25 expression, and cytokine and chemokine production was demonstrated. Gel-shift assays indicated that the transcription factors NF-kappaB and AP-1 were downstream targets of PKC activation. IPP also induced the rapid and persistent phosphorylation of extracellular signal-regulated kinases 1 and 2, p38 mitogen-activated kinase, and stress-activated kinase/c-Jun N-terminal kinase, but only an inhibitor of conventional PKCs blocked these responses. We conclude that the gammadelta T cell response to phosphoantigens is regulated by both novel and conventional PKC isoforms, with PKCtheta being more responsive to ligand stimulation and PKCalpha/beta to growth-factor availability.

Transendothelial migratory pathways of V delta 1+TCR gamma delta+ and V delta 2+TCR gamma delta+ T lymphocytes from healthy donors and multiple sclerosis patients: involvement of phosphatidylinositol 3 kinase and calcium calmodulin-dependent kinase II

We have previously reported that the Vdelta2(+)TCRgammadelta(+) T lymphocyte subset, expressing the NK receptor protein 1a (NKRP1a; CD161), is expanded in patients with relapsing-remitting multiple sclerosis and uses this molecule to migrate through endothelium. In this work, we show that Vdelta1(+) and Vdelta2(+) gammadelta T lymphocytes use distinct signal transduction pathways to accomplish this function. Indeed, we have found that Vdelta1(+) cells lack NKRP1a and selectively express the platelet endothelial cell adhesion molecule 1 (PECAM1; CD31), which drives transendothelial migration of this cell subset, at variance with Vdelta2(+) T cells, which are PECAM1 negative and use NKRP1a for transmigration. Interestingly, when Vdelta2(+) T cells were pretreated with two specific inhibitors of the calcium calmodulin-dependent kinase II KN62 and KN93, but not with the inactive compound KN92, the number of migrating cells and the rate of transmigration were significantly decreased. In turn, the phosphatidylinositol 3 kinase blockers wortmannin and LY294002 exerted a dose-dependent inhibition of Vdelta1(+) cell migration. Finally, NKRP1a and PECAM1 engagement led to activation of different signal transduction pathways: indeed, oligomerization of NKRP1a on Vdelta2(+) T cells activates calcium calmodulin-dependent kinase II, while occupancy of PECAM1 on Vdelta1(+) cells triggers the phosphatidylinositol 3 kinase-dependent Akt/protein kinase Balpha activation. These findings suggest that subsets of gammadelta T lymphocytes may migrate to the site of lesion in multiple sclerosis using two different signaling pathways to extravasate.

Lack of CD27-CD45RA-V gamma 9V delta 2+ T cell effectors in immunocompromised hosts and during active pulmonary tuberculosis

In humans, the circulating pool of mycobacteria-reactive Vgamma9Vdelta2+ T cells is expanded with age and may contribute to Mycobacterium tuberculosis immunosurveillance. We observed that two subsets of Vgamma9Vdelta2+ T cells could be identified on the basis of CD27 expression in immunocompetent adults, showing that functionally differentiated gammadelta T cells have lost CD27 expression. In contrast, the CD27-CD45RA-Vgamma9Vdelta2+ T cell subset of effector cells was absent in cord blood cells from healthy newborns and lacking in the peripheral blood from HIV-infected patients. Moreover, circulating Vgamma9Vdelta2+ T cell effectors were significantly reduced in patients with acute pulmonary tuberculosis, resulting in a reduced frequency of IFN-gamma-producing cells after stimulation with nonpeptidic mycobacterial ligands. These observations indicate that monitoring and boosting gammadelta T cell effectors could be clinically relevant both in immunocompromised hosts and during active tuberculosis disease.

Variable strategy toward carbasugars and relatives. 2. Diversity-based synthesis of beta-D-xylo, beta-D-ribo, beta-L-arabino, and beta-L-lyxo 4a-carbafuranoses and (4a-carbafuranosyl)thiols

The silyloxy diene-based construction of carbasugars, previously exploited for the synthesis of four carbocyclic furanose and pyranose analogues, has been investigated further. By introducing a novel silylative cycloaldolization protocol and by adjusting a couple of minor transformations, the efficiency of this synthetic sequence was greatly improved. Through a series of lactone/thiolactone aldehyde cyclization precursors, four carbafuranoses (4a-carba-beta-D-xylofuranose, 4a-carba-beta-D-ribofuranose, 4a-carba-beta-L-arabinofuranose, and 4a-carba-beta-L-lyxofuranose) and four (carbafuranosyl)thiols [(4a-carba-beta-D-xylofuranosyl)thiol, (4a-carba-beta-D-ribofuranosyl)thiol, (4a-carba-beta-L-arabinofuranosyl)thiol, and (4a-carba-beta-L-lyxofuranosyl)thiol] were assembled. From this study, it was shown that these constructions tolerate a variety of precursors, and in many instances, they are suitable for scaling-up.

Curcumin inhibits activation of Vgamma9Vdelta2 T cells by phosphoantigens and induces apoptosis involving apoptosis-inducing factor and large scale DNA fragmentation

Curcumin, in addition to its role as a spice, has been used for centuries to treat inflammatory disorders. Although the mechanism of action remains unclear, it has been shown to inhibit the activation of NF-kappaB and AP-1, transcription factors required for induction of many proinflammatory mediators. Due to its low toxicity it is currently under consideration as a broad anti-inflammatory, anti-tumor cell agent. In this study we investigated whether curcumin inhibited the response of gammadelta T cells to protease-resistant phosphorylated derivatives found in the cell wall of many pathogens. The results showed that curcumin levels > or =30 microM profoundly inhibited isopentenyl pyrophosphate-induced release of the chemokines macrophage inflammatory protein-1alpha and -1beta and RANTES. Curcumin also blocked isopentenyl pyrophosphate-induced activation of NF-kappaB and AP-1. Commencing around 16 h, treatment with curcumin lead to the induction of cell death that could not be reversed by APC, IL-15, or IL-2. This cytotoxicity was associated with increased annexin V reactivity, nuclear expression of active caspase-3, cleavage of poly(ADP-ribose) polymerase, translocation of apoptosis-inducing factor to the nucleus, and morphological evidence of nuclear disintegration. However, curcumin led to only large scale DNA chromatolysis, as determined by a combination of TUNEL staining and pulse-field and agarose gel electrophoresis, suggesting a predominantly apoptosis-inducing factor-mediated cell death process. We conclude that gammadelta T cells activated by these ubiquitous Ags are highly sensitive to curcumin, and that this effect may contribute to the anti-inflammatory properties of this compound.

T cell response to N-formylated peptides in humans

We present the first evidence of a T lymphocyte response to N-formylated peptides in humans. N-formylated peptide sequences from self (mitochondrial) and foreign (microbial) antigens were used to isolate antigen-specific T cell clones from healthy individuals, including a set of monozygotic twins. The observed response differed from that previously described in mouse (CD4(+) phenotype and MHC class II restriction in humans vs. CD8(+) phenotype and class I restriction in mice). These lymphocytes produce substantial amounts of IFN-gamma. They were isolated in only one of the monozygotic twins, which suggests that their expansion in the healthy immune repertoire is independent of the genetic background. Our result will help in assessing the relevance of N-formylated peptide-specific T cells in protection against infections within the human immune system.

Variable strategy toward carbasugars and relatives. 1. Stereocontrolled synthesis of pseudo-beta-D-gulopyranose, pseudo-beta-D-xylofuranose, (pseudo-beta-D-gulopyranosyl)amine, and (pseudo-beta-D-xylofuranosyl)amine

Four novel, chiral nonracemic carbasugars have been synthesized from 1,2-O-isopropylidene-D-glyceraldehyde. Furan- and pyrrole-based 2-silyloxy dienes--mimics of the alpha,gamma-dianions of gamma-hydroxy- and gamma-aminobutanoic acid, respectively--nicely served to complete the syntheses of two all-oxygen compounds, pseudo-beta-D-gulopyranose and pseudo-beta-D-xylofuranose, and two "anomeric" amino derivatives, (pseudo-beta-D-gulopyranosyl)amine (1,2,4-tri-epi-validamine) and (pseudo-beta-D-xylofuranosyl)amine. Two sequential, highly diastereoselective carbon-carbon bond-forming maneuvers, i.e., a vinylogous crossed aldol addition and an intramolecular aldolization, proved central to these constructions. The fact that readily available heterocyclic diene scaffolds can be employed in the assembly of a varied repertoire of carbasugars and analogues widens the prospects of dienoxy silane chemistry.

Evidence for a role of gammadelta T cells in demyelinating diseases as determined by activation states and responses to lipid antigens

In this report we review current information on the phenotypic and functional properties of gammadelta T cells in demyelinating disorders. The results support the conclusion that although gammadelta T cells show evidence of activation in patients with either multiple sclerosis (MS) or Guillain Barrè syndrome (GBS), differences exist in the phenotypic and functional properties of these cells between the two diseases. In particular, our data indicate that in patients with MS the Vdelta2 subset is activated and that these cells can be induced to secrete high levels of proinflammatory cytokines. In contrast, in patients with GBS, the Vdelta1 subset is expanded and can be induced to secrete cytokines more associated with a humoral response.

Global immune disregulation in multiple sclerosis: from the adaptive response to the innate immunity

Increasing evidences show a global immune disregulation in multiple sclerosis (MS). The possible involvement of myelin and non-myelin (auto-)antigens in the autoaggressive process as well as the disregulation of both adaptive and innate immunity challenge the concept of specific immunotherapy. T cells at the boundary between innate and adaptive immunity, whose immunoregulatory role is becoming increasingly clear, have recently been shown to bear relevance for MS pathogenesis. Global immune interventions (and type I interferons may be considered as such) aimed at interfering with both innate and acquired immune responses seem to be a most promising therapeutic option in MS.

The utility of furan-, pyrrole-, and thiophene-based 2-silyloxy dienes as demonstrated by modular synthesis of annonaceous acetogenin core units and their pyrrolidine and thiolane analogues

We report a modular strategy for obtaining the core units of annonaceous acetogenins and their nitrogen and sulfur analogues, which generates great structural diversity. This synthesis is based on the application of a reiterative vinylogous addition protocol involving a unique triad of silyloxy diene modules, 2-[(tert-butyldimethylsilyl)oxy]furan (TBSOF), N-(tert-butoxycarbonyl)-2-[(tert-butyldimethylsilyl)oxy]pyrrole (TBSOP), and 2-[(tert-butyldimethylsilyl)oxy]thiophene (TBSOT) and suitable heteroatom-stabilized carbenium ions. By combining TBSOF, TBSOP, and TBSOT nucleophilic synthons with certain tetrahydrofuran, pyrrolidine, and thiolane acceptors, the construction of varied, adjacently linked oligo-heterocyclic motifs related to the core segments of the annonaceous acetogenins is assured. At first, the reliability of the pivotal coupling maneuver was certified, by assembling a collection of 18 model constructs, covering all oxygen, nitrogen, and sulfur heteroatom combinations (i.e., compounds 7-9, 13-15, and 19-21). This uniformed protocol was then suited to forge advanced bis-tetrahydrofuran, bis-pyrrolidine, and bis-thiolane scaffolds encompassing the heterocyclic core portion of various binuclear annonaceous acetogenins and relatives. The utility of this synthesis was demonstrated by the preparation of a repertoire of eight isomeric bis-tetrahydrofuran units, 41-48, two bis-pyrrolidine units, 62 and 63, and four bis-thiolane units, 78-81.

Phenotypic and functional properties of gamma delta T cells from patients with Guillain Barré syndrome

In this study we have examined the phenotypic and functional properties of circulating gamma delta T cells in patients with Guillain Barre syndrome (GBS), in normal healthy controls, and in patients with active multiple sclerosis (MS). Cells expressing the Vdelta2 T cell receptor showed elevated expression of the C-lectin receptor NKRP1A in both GBS and MS, suggestive of an activated state. However, in patients with GBS these cells failed to respond to pyrenil-pyrophosphate derivatives and Vdelta2 + T cell clones derived from these patients released lower levels of IFNgamma than Vdelta2 + clones derived from controls and MS patients. In contrast, in patients with GBS the Vdelta1 + subset was expanded, showed elevated expression of NKRPIA and Vdelta1 + clones derived from these patients secreted high levels of IL-4. Our findings of expanded NKRP-1A +, IL-4-producing Vdelta1 T cells in the GBS patients suggests the possibility that these cells are activated by the recognition of non-protein antigens in an MHC-unrestricted manner and contribute to the humoral response to glycolipids that is a hallmark of this disease.

Activation of C-C beta-chemokines in human peripheral blood gammadelta T cells by isopentenyl pyrophosphate and regulation by cytokines

Human gammadelta T lymphocytes respond to viral, bacterial, protozoal, and tumoral antigens, but their precise function remains unknown. In adults the major circulating gammadelta T-cell subset expresses the Vgamma9Vdelta2 T-cell receptor and responds to protease-resistant phosphorylated derivatives found in many pathogens. In this study we show that activation of Vdelta2(+) cells with the nonpeptidic antigen isopentenyl pyrophosphate (IPP) rapidly induces (within 4-12 hours) the C-C chemokines MIP-1alpha, MIP-1beta, and lymphotactin but not MCP-1. The most robust response was obtained for MIP-1beta. IPP induction of MIP-1alpha and MIP-1beta was not affected by costimulation with interleukin-4 (IL-4), IL-10, TGF-beta, or interferon-gamma (INF-gamma). However, IL-12 significantly enhanced IPP-induced expression and release of MIP-1alpha that was down-regulated by TGF-beta whereas the induction of MIP-1beta by IPP+IL-12 was refractory to cotreatment with TGFbeta indicating that these chemokines are differentially regulated by these cytokines. Vdelta2(+) T cells also expressed a wide range of C-C chemokine receptors including CCR1, CCR5, and CCR8, all of which were down-regulated following activation. We conclude that Vdelta2(+) cells can be rapidly induced by components of bacterial cell walls to express high levels of proinflammatory chemokines, supporting an important role for these cells in the early stages of the inflammatory responses to many common pathogens. (Blood. 2000, 95:39-47)