Dendritic Cells Engineered to Express Defined Allo-HLA Peptide Complexes Induce Antigen-specific Cytotoxic T Cells Efficiently Killing Tumour Cells

Most tumour-associated antigens (TAA) are non-mutated self-antigens. The peripheral T cell repertoire is devoid of high-avidity TAA-specific cytotoxic T lymphocytes (CTL) due to self-tolerance. As tolerance is major histocompatibility complex-restricted, T cells may be immunized against TAA presented by a non-self human leucocyte antigen (HLA) molecule and transferred to cancer patients expressing that HLA molecule. Obtaining allo-restricted CTL of high-avidity and low cross-reactivity has, however, proven difficult. Here, we show that dendritic cells transfected with mRNA encoding HLA-A*0201, efficiently present externally loaded peptides from the antigen, Melan-A/MART-1 to T cells from HLA-A*0201-negative donors. CD8⁺ T cells binding HLA-A*0201/MART-1 pentamers were detected already after 12 days of co-culture in 11/11 donors. The majority of cells from pentamer⁺ cell lines were CTL and efficiently killed HLA-A*0201⁺ melanoma cells, whilst sparing HLA-A*0201⁺ B-cells. Allo-restricted CTL specific for peptides from the leukaemia-associated antigens CD33 and CD19 were obtained with comparable efficiency. Collectively, the results show that dendritic cells engineered to express defined allo-HLA peptide complexes are highly efficient in generating CTL specifically reacting with tumour-associated antigens.     

Characterization of T-Cell Receptor Vβ Repertoire in Ovarian Tumour-Reacting CD3+ CD8+ CD4− CTL Lines

T cells from tumour infiltrating lymphocytes (TIL) cultured in media containing IL-2 were shown to mediate in vitro and in vivo antitumour responses. To characterize the T-cell antigen receptor (TCR) Vβ expression in autologous cytotoxic effectors we isolated CD3⁺ CD8⁺ CD4⁻ cells from cultures of TIL and tumour-associated lymphocytes (TAL) and analysed the TCR Vβ repertoire of CD3⁺ CD8⁺ CD4⁻ lines of known HLA-A, -B and -C phenotype, using polymerase chain reaction (PCR). These lines showed preferential lysis of autologous tumours and lysed, to a much lesser extent, NK and LAK cellsensitive targets. Tumour lysis was inhibited by antibodies to CD3 and MHC class I antigens indicating that they are cytotoxic T lymphocytes (CTL). These CD8⁺ CTL lines expressed a broad distribution of TCR Vβ repertoire which was dominated by particular groups of Vβ families in each CTL line. However, no predominant expression of one or the same Vβ segment in all CTL lines was observed although statistical correlations between Vβ family usage and magnitude of the antitumour cytolytic response were found. These results suggest that certain TCR Vβ families may be selected by antigen in ovarian tumour-reactive T cells and this selection may be affected by Ag expression, and/or host factors. To our knowledge, this is the first documentation of TCR Vβ repertoire of human ovarian tumour-reactive CD3⁺ CD8⁺ CD4⁻ CTL from different individuals of known HLA types.     

Local T-Cell Proliferation and Differentiation in Inflammatory Myopathies

Our objective was to investigate the patterns of proliferation and differentiation of infiltrating cells in inflammatory myopathies. Immunohistochemical staining was performed on muscle biopsy specimens from 18 patients with inclusion body myositis, polymyositis and dermatomyositis using monoclonal and polyclonal antibodies.
An abundance of cells were TNF-α⁺ (4–8%), ICAM-1⁺ (7–65%). IFN-γ⁺ (3–6%), and Ki-67⁺ (4–8%). It was shown that 70% of the Ki-67⁺ cells were Ki-67⁺CD3⁺ cells. Very few mononuclear cells were IL-2R⁺. MHC-I expression was found on nearly all muscle fibres in all cases, while MHC-II expression was found on occasional muscle fibres in 1/3 of cases. Analysis of repeated biopsies from four IBM patients after prednisolone treatment showed no change in the proportions of TNF-α, ICAM-1, IFN-γ or Ki-67 positive cells. In inflammatory myopathies there is an intense proliferation and differentiation of inflammatory cells in situ , indicating a local stimulation of the inflammatory process.     

Seasonal Variation and Sex Differences of Circulating Macrophages, Immunoglobulins and Lymphocytes in Healthy School Children

Subpopulations of T and B lymphocytes and levels of serum immunoglobulins G, A, M, E and subclasses G1, G2 and G3 were studied in 45 healthy school children aged 8–16 years during four seasons of the year. There were significant increases in CD4⁺ T helper cells, total T lymphocytes and CD4⁺/CD8⁺ (helper/cytotoxic) T-cell ratio during the spring season. While the levels of CD8⁺ T cells and total B lymphocytes remained statistically unchanged during all four seasons, the levels of natural (HNK-1) killer cells and macrophages increased significantly during the autumn and summer seasons respectively. The levels of immunoglobulins G, A, M and E remained statistically unchanged during all four seasons. Girls had higher levels of CD4⁺ T cells and a higher CD4⁺/CD8⁺ T-cell ratio than boys. Girls also had slightly higher levels of immunoglobulin G and M. These observations suggest that seasonal variations of some immunological parameters occur in healthy children. This may be an adaptive response to variable climatic and other environmental factors. These natural variations due to seasonal changes should be taken into account when immunological tests are used in clinical investigations.     

Immunohistochemical characterization of thymic macrophages in normal and treated rats: a differential sensitivity to cyclosporine A

In the present study, a set of two monoclonal antibodies (TRPM1, TRPM2) was used to investigate the macrophage populations in the rat thymus and their different sensitivities to cyclosporine-A (CsA). With double immunohistochemical staining we demonstrated that, in the normal rat thymus, there are 3 populations of macrophages (TRPM1⁺, TRPM1/2⁺, TRPM2⁺), present in different proportions throughout the thymus. In the outer cortex TRPM1⁺ and TRPM1/2⁺ were present, but the TRPM1/2⁺ cells were more numerous. No TRPM2⁺ cells were observed in this area. The cortex and medulla showed all 3 types of cells with a majority of TRPM1/2⁺ cells. In the corticomedullary zone (CMZ) TRPM1/2⁺ and TRPM2⁺ macrophages were present in about equal proportion while only a few TRPM1⁺ cells were observed. After CsA treatment (for 21 days) profound changes occurred in the thymus; we observed a complete disappearance of the thymic medulla and a reduction in the total number of macrophages. The TRPM1⁺ macrophages had been eliminated, a few TRPM1/2⁺ cells were found while many of the cells were TRPM2⁺. The presence of the macrophages in different thymic areas suggests that they are a very heterogeneous population. The possible significance of the macrophage heterogeneity and the relationship to CsA sensitivity is discussed.     

The Effects of Mitogens, IL-2 and Anti-CD3 Antibody on the T-Cell Receptor Vβ Repertoire

Phytohaemagglutinin (PHA), Concanavalin A (Con A), interleukin-2 (IL-2), and monoclonal antibodies to CD3 (CD3MoAbs) are used for the assessment of the T-cell receptor (TCR) BV gene family expression in autoimmune disorders and multiple sclerosis, and to produce clones for assessment of cytokine profiles in progressive human immunodeficiency virus infection. The authors examined the effects of these stimulants on the TCR Vβ repertoire of resting and blastic CD4⁺ and CD8⁺ normal human peripheral blood lymphocytes, using three-colour cytofluorometry and a panel of anti-TCR Vβ monoclonal antibodies. IL-2 was associated with an increased percentage of blastic CD4⁺ cells expressing V_β5.1 (from median of 3.7% to 8.0%, P  = 0.0002) and blastic CD8⁺ cells expressing V_β5.3 (1.0 to 1.5%, P  = 0.0039). CD3MoAb caused a slight increase in V_β6.7 + blastic CD4⁺ cells (4.5 to 6.9%, P  = 0.0078). PHA did not alter the Vβ repertoire of blastic cells. Con A caused skewing in CD8⁺ blastic cells, toward expression of V_β5.2/5.3 (3.1 to 8.1%) and V_β5.3 (0.8 to 4.8%) ( P  = 0.0020). Thus, IL-2 stimulation causes slight alterations in the Vβ repertoire that should be taken into account in certain research settings. Con A produced skewing in CD8⁺ blastic cells suggesting that, in the presence of CD8, either Con A binds selectively to certain Vβ or the three-dimensional complex created by Con A's binding to other T-cell surface molecules induces preferential V_β5 stimulation.     

Kinetic Analysis of Subset Growth and B-Cell Activation in Pokeweed Mitogen-Stimulated Cultures of Peripheral Blood Mononuclear Cells Depleted of or Enriched for OKT8+ Cells

Peripheral blood mononuclcar cells (PBMN) that were depleted of OKT8⁺ cells and stimulated with pokeweed mitogen (PWM) produced higher cell yields and higher numbers of plaque-forming cells than unfractionated PBMN. Conversely, OKT8-enriched PBMN, prepared by mixing unfractionated and OKT8⁺ cells in a ratio of 3:1, gave reduced cell growth and B-cell activation. In OKT8-depleted cultures, B cells, OKT4⁺ cells, OKT8⁺ cells, and OKM1⁺ cells increased in number between days 4 and 7 of culture by factors of 9.8, 5.9, 20.1, and 5.6 respectively, whereas growth rates for these subsets were 2.4, 1.0, 2.0, and 1.3 in unfractionated cultures and 0.9, 1.0, 1.2, and 0.6 in cultures enriched for OKT8⁺ cells. On day 7 of culture, 73±10% of B cells secreted immunoglobulin in unfractionated cultures, whereas only 21±10% of B cells were activated in OKT8-enriched cultures. Surprisingly, PWM stimulation of OKT8-depleted PBMN produced only 40±12% activated B cells.     

Selective Cytotoxicity of Two Rodent T Cell Lymphomas to Rat Yolk Sac Tumours Involves a Retroviral Envelope Protein Expressed by the Lymphoma

A Gross virus induced rat T cell lymphoma G1-Tc1 and a Moloney virus induced mouse T cell lymphoma YAC-1 are shown to exert a strong cytotoxic activity against rat yolk sac tumours but not to various types of rat, mouse or human normal cells or tumour cell lines including carcinomas, sarcomas, lymphomas and gliomas. Both lymphomas are CD3⁺, CD4⁻, CD8⁻ and T-cell receptor (TCR)αβ⁺. The cytotoxicity was not MHC restricted or dependent on the density of MHC class I of the target cells, and the mouse lymphoma killed the rat yolk sac tumour target. The cytotoxic action was fast and up to 80% specific killing was observed in 4-h ⁵¹Cr release assays. A rat B cell hybridoma was established from a Wistar/Furth (WF) rat immunized with the syngeneic lymphoma G1-Tc1 producing an immunoglobulin (Ig)G2c monoclonal antibody (MoAb) 1F2. This binds to the lymphomas G1-Tc1 and YAC-1 and also to a murine non-cytolytic Rauscher lymphoma RMA, but not to any other of several rat, mouse or human cell types tested. The 1F2 completely inhibited the killing of rat yolk sac tumours by the two cytolytic lymphomas, but did not interfere with the killing mediated by natural killer (NK) cells or cytolytic lymphokine-activated killer (LAK) cells. Immunochemical analysis of solubilized cell membranes of the lymphoma G1-Tc1 demonstrates that the 1F2 antibody recognizes an epitope on a retroviral gp 70 envelope protein. This indicates that a retroviral protein is involved in the lytic activity of the two lymphomas.     

Sequential Analysis of Distributions of Donor-derived Thymocytes Bearing T-cell Antigen Receptor (TCR) and Donor-derived la+ Cells in Thymuses of Fully Allogeneic Bone Marrow Chimera in Mice

Lethally irradiated SJL/J mice were reconstituted with B10 bone marrow cells, and the process of thymic reconstitution by donor derived cells positive for I- A or Vβ8 molecules was investigated. The donor-derived la⁺ cells appeared in the medulla on day 7 after reconstitution. The la+ cells became confluent up to day 14, and the cellularity in the medulla on day 17 was almost the same as that in the normal thymus. Dull Vβ8⁺ thymocytes were first recognized in the cortex on day 10 and were identifiable in the medulla by day 14. The Vβ8⁺ cells seemed to be mainly CD4⁺8⁺ double-positive. Furthermore, most of the Vg8'cells in the medulla of chimeras given cyclosporin A for 3 weeks after reconstitution appeared to be CD4⁺8⁺. The present findings demonstrate that CD4 8+ thymocytes which bear a low concentration of TCR exist in the thymic medulla at a relatively early stage when donor-derived la⁺ cells have already settled there. The coincidental appearance and coexistence of la⁺ cells and TCR⁺ thymocytes in the medulla suggest that these histological characteristics may be related to the selection of thymocytes in this area.     

Anti CD5 Sustains the Proliferative Response of IgM-Activated Human CD5+B Cells

The CD5 molecule is expressed by most T cells but it is present on a minor B cell subset. Whilst several studies have provided information on the physiological role of T cell CD5, the functional role of CD5 on B lymphocytes remains unclear. To address this question, tonsillar CD5⁺ B cells were sorted by dual-colour fluorescence and FACS. Sorted cells were stimulated with polyclonal anti-IgM antibodies (Ab), and monoclonal (MoAb) F(ab')₂ fragments of anti-CD5. Proliferative responses were evaluated by enumeration of Ki-67 positive cells using quantitative flow cytometry. Co-stimulation with anti-CD5 MoAb for 3 days did not affect the anti-IgM and IL2-induced proliferation of CD5⁺ B cells. This was seen under conditions where the anti-CD5 was soluble, adsorbed to the microwells or cross-linked by anti-mouse antibodies. Fewer CD25⁺ cells were detected, however, in the presence of anti-CD5. In contrast, the proliferative response of CD5⁺ B cells prestimulated for 3 days with IL-2 and anti-IgM, was sustained in a further 3-day culture period when anti-CD5 was added. It is concluded that CD5 occupancy might provide an additional signal to activated CD5⁺ B cells favouring their proliferation and differentiation into autoantibody secreting cells.     

A2B5 Cells from Human Glioblastoma have Cancer Stem Cell Properties

Glioblastomas, like other cancers, harbor small cell populations with the capability of sustaining tumor formation. These cells are referred to as cancer stem cells. We isolated cells expressing the surface marker A2B5 from three human glioblastomas (GBM) and showed that after grafting into nude mice, they generated dense and highly infiltrative tumors. Then, we extensively studied A2B5⁺ cells isolated from 11 human GBM. These cells display neurosphere-like, self-renewal, asymmetrical cell division properties and have multipotency capability. Stereotactic xenografts of dissociated A2B5⁺-derived secondary spheres revealed that as few as 1000 cells produced a tumor. Moreover, flow cytometry characterization of A2B5⁺-derived spheres revealed three distinct populations of cells: A2B5⁺/CD133⁺, A2B5⁺/CD133^- and A2B5^-/CD133^-, with striking proportion differences among GBM. Both A2B5⁺/CD133⁺ and A2B5⁺/CD133^- cell fractions displayed a high proliferative index, the potential to generate spheres and produced tumors in nude mice. Finally, we generated two green fluorescent protein-cell lines that display—after serum induction—distinct proliferative and migratory properties, and differ in their CD133 level of expression. Taken together, our results suggest that transformed A2B5⁺ cells are crucial for the initiation and maintenance of GBM, although CD133 expression is more involved in determining the tumor's behavior.     

Effect of 12 Neutralizing Anti-Cytokine Antibodies on In Vitro Activation of B-Cells. Interleukin-12 is Required by B1a but not B2 Cells

Normal human peripheral blood mononuclear cells, depleted of most monocytes and virtually all CD8-positive cells, were stimulated in vitro with pokeweed mitogen plus Staphylococcus aureus Cowan I in the presence or absence of variousneutralizing anti-cytokine antibodies. Numbers of CD5⁺ and CD5⁻ immunoglobulin-secreting cells were determined using the protein A haemolytic plaque assay after labelling B1a cells with anti-CD5-coated beads. Antibodiesagainst IL-2, IL-5 and IL-10 had little or no effect on plaque-forming cell (PFC) induction; anti-IL-6, -TNFα and -TGFβ enhanced PFC induction; anti-IL-1α, -IL-1β, -IL-4, -IFNγ and -IL-13 suppressed PFC induction. B1a and B2 cells were equally affected by cytokine deprivation using these 11 neutralizing antibodies. In contrast, neutralizing anti-IL-12 suppressed induction of CD5⁺ but not CD5⁻ PFC. Furthermore, recombinant IL-12, if added during thefirst 48 h of culture, enhanced CD5⁺ PFC induction while marginally suppressing (IgG-) or not affecting (IgA-, IgM-) induction of CD5⁻ PFC. IL-12 did not preferentially increase survival in culture of B1a cells norinduce expression of CD5 on B2-cells. Further studies are required to determine whether manipulation of B1a and B2 subsets in vivo using IL-12 could be achieved in clinical situations where imbalances in the two populations have beenobserved.     

Cytokine Dependence of Human to Mouse Graft-versus-Host Disease

Human peripheral blood leucocytes (PBL) induce chronic graft versus-host disease (GvHD) in non-conditioned severe combined immunodeficient mice. Chronic GvHD was observed in such animals after transplantation of 6 × 10⁷ human PBL per g body weight. However, acute xenogeneic GvHD results from grafting at least 2 × 10⁷ human PBL per g body weight to heavily conditioned murine hosts. The large numbers of human PBL were thought to be required fo produce above threshold amounts of certain cytokines. We show that treatment of the recipient mice with human interleukin 2 reduces the number of cells to inflict acute GvHD by a factor of ten. Human T cells and not B cells or macrophages, were previously shown to generate acute xenogeneic GvHD, when selected cell types from peripheral blood were grafted. Most of the infiltrating cells had the CD4⁺ phenotype. We demonstrate that CD4⁺ T cells are the main mediator, as the disease is abrogated by treating the mice with cytotoxic CD4 antibodies, but not with CD8 antibodies. A survival pattern, similar to that seen in GvHD, was induced by transplantation of a Herpesvirus saimiri transformed human CD4⁺ clonal T cell line in conjunction with daily interleukin 2 injections. Herpesvirus saimiri transformed human T cells allow easily reproducible graft properties in chimeric mouse models for human diseases.     

An unbiased stereological study on subpopulations of rat liver macrophages and on their numerical relation with the hepatocytes and stellate cells

Studies on liver macrophages have elucidated their key roles in immunological, fibrotic and regenerative responses, and shown that macrophages are not a homogeneous population. In the rat, two sets of liver macrophages coexist, identified by ED1 and ED2 antibodies. Those sets have different quantitative responses in liver injuries and may have different tasks throughout the injury and recovery phases. Nevertheless, the total number (N), number per gram (N g⁻¹) and proportion of those macrophages in relation to other liver cells has never been quantified using design-based stereology. Thus, we combined immunocytochemistry with those tools to produce an unbiased estimate of the N of ED1⁺ and of ED2⁺ cells. A smooth fractionator sampling scheme was applied to the liver of five male Wistar rats (3 months old), to obtain systematic uniform random sections (30 µm thick); these were immunostained with the monoclonal antibodies: ED1, a pan-macrophagic marker; and ED2, which identifies the completely differentiated macrophages, i.e. Kupffer cells. The N of ED1⁺ cells was 340 × 10⁶, estimated with a coefficient of error (CE) of 0.04, and that of ED2⁺ cells was 283 × 10⁶, with a CE of 0.05. These figures correspond to 10.7% and 8.9%, respectively, of the total liver cells. The new data constitute reference values for correlative inferences. Also, the methodological strategy, by its accuracy and precision, is valuable for future investigations on the liver cell composition in various models of disease, and especially for studying the more subtle variations that occur during the injury and recovery phases.     

Expression of CD23 antigen and its ligands in children with intrinsic and extrinsic asthma

The role of the low-affinity IgE receptor CD23 in immune reactions has been further emphasized by recent discoveries of novel surface ligands for CD23: CD21, CD11b, and CD11c. We previously observed the difference between the expression of CD23 and CD21 antigens in children suffering from extrinsic asthma when compared to healthy controls. In the present study, we investigated the expression of CD23 and its ligand CD21 on CD20⁺B cells in 44 asthmatic children (23 allergic and 21 nonallergic) using three-color immunofluorescence analysis. In addition, the expression of two other ligands for CD23, CD11b, and CD11c, on T cells (CD3⁺), a subpopulation of T cells (CD4⁺ and CD8⁺), natural killer cells (CD56⁺), and monocytes (CD14⁺) was tested by two-color immunofluorescence analysis in 12 allergic and 14 nonallergic children. We found that children with extrinsic asthma had higher levels of CD23⁺ B cells than those with intrinsic asthma. No difference was observed in the percentage of either CD23⁺CD21⁺ or CD23^- CD21⁺ B cells. The CD11b antigen was expressed on each tested population, but only on CD4⁺ T cells was CD11b significantly increased in children with extrinsic asthma. CD11c was expressed mainly on monocytes, and no difference was observed between tested groups. The increased percentage of CD11b antigen on CD4⁺ T cells and the increased percentage of CD23 antigen on B cells in children with extrinsic asthma provide further evidence of the immunologic differences between intrinsic and extrinsic asthma.     

Population Dynamics of CD4+ T Cells Lacking Thy-1 in Murine Retrovirus-Induced Immunodeficiency Syndrome (MAIDS)

Increased numbers of CD4⁺ Thy-1 cells have been described in the spleen (SP) of mice with retrovirusinduced immunodeliciency (MAIDS). Since this phenotypic abnormality might have considerable functional importance, the expansion of the CD4⁺ Thy-1 subset in MAIDS was characterized further. CD4⁺ Thy-1⁻ and Thy-1⁺ T-cell is from infected mice expressed similar densities of CD3 and TCR γ/β. In contrast, the Thy-I⁻ subset was uniformly CD44^hi, even early in the disease when part of Thy-I⁺ cells were still CD44¹⁰. The emergence of CD4⁺ Thy-1⁻cells occurred first in SP and lymph nodes and was observed later in thymus. The important fraction ofCD4⁺ cells lacking Thy-1 normally present in Peyer's patches was only weakly modified. Despite the major expansion of the CD4⁺ Thy-1⁻ phenotype. the proliferating fraction was not higher in this subset than in CD4⁺ Thy-1⁺ cells from infeeted miee. Persistence after hydroxyurea administration was identical in both subsets, indicating similar mean cell lifespans. Taken together, these results show that the major expansion of CD4⁺ Thy-I⁻ T-cells in MAIDS is not ascribable solely to increased proliferation within this subset. Phenotypic analysis suggests that CD4⁺ Thy-I⁻ cells result from the differentiation of Thy-I⁺ cells induced by activation signals related to retroviral infection.     

CD 127- and FoxP3+ expression on CD25+CD4+ T regulatory cells upon specific diabetogeneic stimulation in high-risk relatives of type 1 diabetes mellitus patients

Abnormalities in CD4⁺CD25⁺ regulatory T cells (Treg) may contribute to type 1 diabetes (T1D) development. First-degree relatives of T1D patients are at increased risk especially when they carry certain HLA II haplotypes. Using two novel markers of CD4⁺CD25⁺ Treg (CD127⁻ and FoxP3⁺ respectively), we evaluated number and function of Treg after specific stimulation with diabetogeneic autoantigens in 11 high-risk (according to HLA-linked risk) relatives of T1D patients and 14 age-matched healthy controls using a cytokine secretion assay based on interferon- γ (IFN- γ ) production. High-risk relatives of T1D patients had significantly lower pre- and post-stimulatory number of CD127⁻ Treg than that of healthy controls ( P  < 0.05). Labelling Treg with FoxP3⁺ demonstrated similar trend but did not reach statistical significance. Although the stimulation with diabetogenic autoantigens did not lead to a significant change in number of Treg in both groups, the defective function of Treg was performed by significantly higher activation of diabetogeneic T cells in high-risk relatives of T1D patients compared to healthy controls ( P  ≤ 0.02). Individuals at increased HLA-associated genetic risk for T1D showed defects in Treg.     

Cytokine and chemokine expression in the skin from patients with maculopapular exanthema to drugs

Background:  Maculopapular exanthema (MPE) is the most frequent clinical manifestation of nonimmediate allergic reactions to drugs and T helper 1 (Th1) cytokines and CD4⁺ T cells have been shown to play an important role in its pathogenesis. We assessed the role of cytokines and chemokines and their receptors in the pathogenesis of MPE.
Methods:  We evaluated skin biopsies and peripheral CD4⁺ and CD8⁺ T cells from 27 patients during the acute phase of the reaction and 26 exposed controls. Semiquantitative real-time PCR was performed to determine the expression of cytokines and chemokines and their receptors and immunohistochemistry was used to determine the same chemokines and their receptor proteins in skin.
Results:  There was a high expression of the Th1 cytokines interferon-γ ( P  = 0.006) and tumor necrosis factor-α ( P  = 0.022) in skin and CD4⁺ T cells ( P  = 0.007 and P  = 0.005, respectively); and of the Th1 chemokines CXCL9 ( P  = 0.005) and CXCL10 ( P  = 0.028) in the skin, while their receptor CXCR3 was increased in skin ( P  = 0.006) and CD4⁺ T cells ( P  = 0.03). Homing chemokine receptors were also increased: CCR6 in skin ( P  = 0.026) and CD4⁺ T cells ( P  = 0.016), and CCR10 only in CD4⁺ T cells ( P  = 0.016), as well as their ligands, CCL20 and CCL27, in skin alone. Immunohistochemistry confirmed these results.
Conclusions:  These data show significant differences in the expression of chemokines and chemokine receptors, related with a Th1 profile, in both skin biopsies and peripheral CD4⁺ T cells in patients with drug-induced MPE.     

Restricted and Individual Usage of T-cell Receptor β-Gene Variables in Nickel-Induced CD4+ and CD8+ Cells

Nickel allergy is manifested as contact allergic eczema elicited by delayed-type hypersensitivity, the reaction being mediated by T lymphocytes. We examined the T-cell receptor (TCR) β-chain variable gene segment (Vβ) use of nickel-induced CD4⁺ and CD8⁺ T cells in the peripheral blood of nickel-sensitive and non-sensitized subjects. The results show that each patient had an individual Vβ repertoire overexpressed, these being in CD4⁺ cells Vβ10 and Vβ13 (in subject A); Vβ1, Vβ2, Vβ13 and Vβ21 (subject B); Vβ1 and Vβ10 (subject C); Vβ9 and Vβ19 (subject D). Thus, no single Vβ gene dominated in a majority of the CD4⁺ samples. The Vβ genes overexpressed in patient CD8⁺ nickel-induced T cells were Vβ1 (in subject A), Vβ1 (subject B), Vβ1 and Vβ2 (subject C) and Vβ7 (subject D), domination of Vβ1 being seen in most of the CD8⁺ samples (75%). No specific overexpression of any Vβ genes in the nickel-allergic subjects was found in comparison with the non-sensitized subjects. In conclusion, an individual pattern of restricted Vβ genes was induced with nickel in CD4⁺ and CD8⁺ T cells in each nickel allergy patient.