Decreases in alpha beta T cell receptor negative T cells and CD8 cells, and an increase in CD4+ CD8+ cells in active Hashimoto''s disease and subacute thyroiditis.

We examined peripheral lymphocyte subsets in patients with autoimmune thyroid disease, or subacute thyroiditis, in the active stage when possible. During destructive thyrotoxicosis arising from alpha beta T cell receptor (TCR) negative T (WT31-CD3+) cells and CD8 (CD4-CD8+) cells decreased and those of CD4+CD8+ cells increased slightly, resulting in proportional increases in CD4 (CD4+CD8-) cells, non-T, non-B (CD5-CD19-) cells, and the CD4/CD8 cell ratio. Changes were similar in active subacute thyroiditis. During stimulative thyrotoxicosis in active Graves' disease, the numbers of such T lymphocyte subsets were not changed, but only the number of CD5+ B (CD5+CD19+) cells increased markedly, resulting in proportional decreases in total T (CD3+) cells, alpha beta+ TCR T (WT31+CD3+) cells, CD8 cells, and non-T, non-B cells. A serial study of some of the patients showed opposite changes in alpha beta TCR- T cells, the CD4/CD8 cell ratio, and CD5+ B cells between the active stages of Graves' and Hashimoto's diseases. alpha beta TCR- T cells were mostly gamma delta TCR+ T (IIF2+ CD3+) cells in these patients. These data suggest that alpha beta TCR-T (gamma delta TCR+ T), CD8, and CD4+ CD8+ cells are important in thyroid destruction in Hashimoto's disease and subacute thyroiditis, and that CD5+ B cells are important in thyroid stimulation in Graves' disease.     

Intrathyroidal HLA-DR-positive lymphocytes in Hashimoto's disease: increases in CD8 and Leu7 cells

The peripheral and intrathyroidal HLA-DR-positive (DR+) lymphocyte subsets that were activated in vivo in patients with Hashimoto's disease (HD) were examined by two-color flow cytometry with monoclonal antibodies against CD3, CD4, CD8, Leu7, CD19, and HLA-DR antigens. The proportions of total DR+ cells in peripheral lymphocytes and the proportions of DR+ cells in the CD3+, CD4+, and Leu7+ lymphocytes were higher in patients with HD than in normal controls. Furthermore, the proportions of total DR+ cells among intrathyroidal lymphocytes isolated from thyroid tissue of individuals with HD were higher than those in their peripheral lymphocytes. Interestingly, the proportions of DR+ cells among the CD3+, CD8+, and Leu7+ lymphocytes in the thyroid were greatly increased. These data indicate that (i) CD3+ T, especially CD4+ T helper/inducer, lymphocytes and Leu7+ NK/K cells are activated in peripheral blood in Hashimoto's disease and that (ii) CD3+ T, especially CD8+ T suppressor/cytotoxic, lymphocytes and Leu7+ NK/K cells are predominantly activated in Hashimoto's goiter, suggesting an increase of cell-mediated cytotoxicity in the thyroid in Hashimoto's disease.     

The majority of the activated T cells in the blood of insulin-dependent diabetes mellitus (IDDM) patients are CD4+.

Twenty-five recently diagnosed insulin-dependent diabetic patients were screened for the presence of activated T lymphocytes using the anti-IL-2 receptor monoclonal antibody; thirteen had elevated levels of activated T lymphocytes. The activated cells were mostly confined to the CD4 subset, with the CD4/CD8 ratio in IL-2 receptor expressing cells averaging 5 +/- 1 (s.d.) compared with 1.3 +/- 0.3 for all T cells. In recent onset insulin-dependent diabetes blood there was no lack of CD4 CD45R+ (suppressor/inducer) T cells. The activated IL-2 receptor, expressing cells belonged to both CD4 subsets, 'helper inducer' (CD44B4) and 'suppressor inducer', (CD42H4).     

Gamma interferon production and two-color fluorescence flow cytometry analysis of peripheral blood mononuclear cells in allogeneic bone marrow transplant recipients

Gamma interferon (gamma-INF) production was studied and two-color fluorescence flow cytometry analysis was done on the peripheral blood mononuclear cells (PBMC) in allogeneic bone marrow transplant recipients. Gamma INF was not detected in any patients within a year after transplantation whether PBMC was stimulated with PHA or not. A year after transplantation, gamma-INF was produced in the normal level in the stimulated and unstimulated PBMC. The number of suppressor-inducer T cells (CD4+2H4+) was decreased and that of suppressor T cells (CD11+CD8+) was normal. The numbers of helper-inducer T cells (CD4+4B4+) and helper T cells (CD4+2H4-) were normal. The numbers of activated helper-inducer T cells (CD4+HLA-DR+) and suppressor-cytotoxic T cells (CD8+HLA-DR+) were elevated. In the NK cells, Leu7+ CD16-cells were elevated, whereas Leu7+CD16+ cells and Leu7-CD16+ cells were normal. Leu7+CD8+ cells were elevated. These results indicated immunodeficiency after transplantation.     

The alternation of CD8+ cells and its subpopulations by serial monitoring of peripheral blood lymphocytes of renal allograft recipients

To catch and treat the initial alternation of a rejection and infection, we have introduced the serial analysis of lymphocyte surface antigens of peripheral blood lymphocytes by flow cytometry for 9 cases of renal allo-graft recipients since September 30 in 1988. In three recipients without rejection and infection, we found that T8+(CD8+), T8+Mo1+(CD11b+), T8+Mo1-(CD11b-), and T8+IL-2R+(CD25+) subsets were variable for first 20 days and then they were stable. However, another activated CD8+ T-cell subset such as T8+I2+(HLA-DR+) subset gradually increased after first 20 days, so that we investigated the different processes between these two activated subsets. On primary rejection of 5 cases, T8+I2+ and T8+IL-2R+ subsets showed peak formations within 2 days before the rejection. Two of these 5 cases resisted to a primary rejection therapy and showed rebounding arise of these subsets. We could easily convert to OKT-3 rescue therapy and treat them successfully. In order to catch the initial alternation of the primary rejection and treat the rebounding reaction successfully, we should monitor the T8+I2+ and T8+IL-2R+ subsets daily for first 2 weeks and after then 3 times a week.     

Intrathyroidal accumulation of T cell phenotypes in autoimmune thyroid disease.

In this study we have correlated peripheral T cell subset phenotypes with intrathyroidal lymphocyte accumulation in patients with autoimmune thyroid disease (Graves' and Hashimoto's disease). Our study utilized euthyroid family members for one of our control groups (n = 48) thus significantly limiting familial, but not disease-specific, influences on these T cell phenotypes. Our principal new observations were found only in patients with Graves' disease. As previously reported, there was a decrease in CD8+ (suppressor/cytotoxic) T cells in the peripheral blood of patients with untreated hyperthyroid Graves' disease (n = 27) (mean +/- SEM, 19 +/- 1.1% in patients compared with 25 +/- 1.2% in controls, p = 0.03), a finding not observed in treated, euthyroid Graves' disease patients or their relatives. However, the relative number of CD8+ T cells, assessed by CD4:CD8 ratios, was increased in the intrathyroidal T cell populations (n = 10), when compared to normal and patient peripheral blood. There were no consistent changes in total CD4+ (helper) T cells in the peripheral blood of patients with treated and untreated Graves' disease but a reduction in CD4+2H4+ (suppressor-inducer) T cells was seen in patients undergoing surgery for Graves' disease (13 +/- 6.9% compared with 39 +/- 3.4%). Again, however, this T cell subset was increased within the target organ of the same patients (41 +/- 5.9%). These data point to either a selective accumulation, or a specific "homing", of certain T cell subsets within the thyroid gland of patients with Graves' disease where T cell differentiation may be strongly influenced by antithyroid drug treatment and the local immune environment.     

Intrathyroidal activated (Ia+) T-lymphocyte CD+ subsets and B cells in Graves' hyperthyroidism respond rapidly to propylthiouracil therapy: demonstration using fine needle aspirates and two-colour laser flow cytometry.

Using a rapid (whole blood lysis) single laser microfluorocytometric technique that permitted the simultaneous analysis of two monoclonal antibody surface markers tagged with different fluorescent dyes, the intrathyroidal (IT) and peripheral blood (PB) activated [Ia+ = DR+] T-lymphocyte CD3+ subsets and [F(ab')2+] B cells were studied in hyperthyroid patients with Graves' disease (GD) before and after 1-4 months of propylthiouracil (PTU) therapy. IT lymphocytes were obtained by serial fine needle aspiration. In untreated patients a marked quantitative (approximately < 10 fold) increase in activated (Ia+ CD3+) T-lymphocytes as well as CD4+ and CD8+ subsets, for IT compared to PB sites, was found. The percentages of Ia+ CD4+ and Ia+ CD8+ within Ia+ CD3+ were not significantly different between the two sources of T cells. F(ab')2+. B cells were significantly increased (approximately 2-3 fold) in IT compared to PB. In hyperthyroid GD patients, PTU therapy induced rapid and specific changes within the Ia+ CD3+ subsets, namely a reduction in the Ia+ CD4+ subset and an increase in the Ia+ CD8+ subset, resulting in a marked decrease in the Ia+ CD4+/Ia+ CD8+ ratio. These changes occurred in association with a reduction in serum T4 and T3 concentration. No significant changes could be detected within the total (predominantly non-activated) CD3+, CD4+ or CD8+ lymphocyte subsets within PB and only a small decrease in the CD4+/CD8+ ratio was demonstrated in IT, following PTU treatment.(ABSTRACT TRUNCATED AT 250 WORDS)     

Double phenotyping of immunoregulatory T cell subsets in patients with allergic asthma

In order to determine whether the dissection of helper/inducer (CD4 +) and suppressor/cytotoxic (CD8 +) lymphocyte subsets with Leu 8 reagent would reveal any differences between allergic asthma patients and non-atopic controls, we compared in both groups the 'true helper' T cell subset (Leu 8 - CD4 +), responsible for the major helper effect, and one of the suppressor T cell subpopulations (Leu 8 - CD8 +). Peripheral blood mononuclear cells from sixty-nine individuals, including nineteen extrinsic asthmatics, fifteen intrinsic asthmatics, seventeen patients with chronic obstructive lung disease and eighteen healthy controls, were comparatively analysed. Although total CD4 + cells and total CD8 + cells were similar for all groups, we found in the extrinsic asthma patients group a significant increase in the number of 'true helper' T cell sublineage (Leu 8 - CD4 +) and of suppressor cells expressing Leu 8 - CD8 + phenotype. Such imbalances may be implicated in the pathogenesis of atopic asthma.     

Interleukin 2 receptor expression by human blood lymphocytes after vaccination with pneumococcal polysaccharides.

Proliferative responses of unseparated peripheral blood mononuclear cells (PBMC) and blood T cells to recombinant interleukin 2 (rIL-2) were significantly increased 7-21 days after the vaccination with pneumococcal polysaccharides (PPS). In contrast, non-T cells expressed increased responsiveness to rIL-2 only on post-vaccination day 7. Analysis of the proliferative response to rIL-2 among lymphocyte subsets (CD4+Leu8+, CD4+Leu8-, CD8+Leu8+, CD8+Leu8-, CD20+) in cultures of unseparated PBMC revealed that the CD8+Leu8- T cells expressed increased responsiveness 7-14 days after vaccination, whereas neither CD4+ (Leu8+ and Leu8-) nor CD8+Leu8+ T cells showed significantly increased responsiveness after vaccination. The CD20+ B cells, like non-T cells, expressed increased responsiveness to rIL-27 days after the vaccination only. Expression of the 55 kD low-affinity interleukin 2 receptor (IL-2R, CD 25) on freshly isolated PBMC, as judged by direct fluorescence staining with a MoAb anti-55 kD chain, was low (less than 3%) and an increased expression of this receptor was not detected following vaccination. In contrast, binding of 125I-labelled IL-2 to freshly isolated PBMC increased following vaccination (day 7). Scatchard plot analysis revealed a modest increase in the expression of high-affinity IL-2R (Kd = 1-2 pM), whereas the increase in expression of the 75-kD, intermediate-affinity IL-2R (Kd = 300 pM) was more pronounced (from 195 to 295 (means) receptors per PBMC). It is concluded that, following vaccination with PPS increased IL-2R expression is induced on blood lymphocytes. These investigations suggest a role for T cells in the human immune response against PPS.     

Identification of lymphocyte subsets in peripheral blood and thyroid gland in Graves' disease by alpha-naphthyl-acetate-esterase reaction

T lymphocyte subsets were prospectively examined in the peripheral blood and thyroid aspirates of 10 patients with hyperthyroid Graves' disease before and after treatment with methimazole and attainment of euthyroidism. T lymphocyte subsets were identified with monoclonal antibodies and pattern of alpha-naphthyl-acetate esterase (ANAE) staining pattern in the case of peripheral blood and ANAE staining pattern with thyroid aspirate smears. Before treatment, OKT8+ lymphocytes were significantly decreased (18.4% +/- 4.8) (S. D.) in the patients compared to control (28.8 +/- 6.7%, p less than 0.05), the OKT4/OKT8 ratio was increased (2.92 vs 2.11). Percent OKT8+ lymphocytes were not different from the controls when the ten patients had been rendered euthyroid. ANAE mononuclear cells with a diffuse pattern (presumed suppressor cells) were 4.2% +/- 1.8 before treatment and 8.3 +/- 2.4 (p less than 0.05) after treatment and 11.5% +/- 2.2 in controls. ANAE mononuclear cells with diffuse pattern represented 4.2% +/- 1.8 of the mononuclear cells infiltrating the thyroid gland of untreated patients and rose to 8.3% +/- 2.4 after the patients had become euthyroid. ANAE negative cells (B cells and some T cells) were increased in the thyroid of untreated patients. It is concluded that mononuclear cells with presumed suppressor T cell phenotype are decreased in the blood and thyroid glands of patients with active Graves' disease and that this defect is corrected when euthyroidism has been established.     

Pneumonitis in bone marrow transplant recipients results from a local immune response.

Eighteen recipients of allogeneic T cell-depleted bone marrow who developed 22 episodes of interstitial pneumonitis were investigated by bronchoalveolar lavage for the cause of pneumonitis. The cells obtained were examined using a panel of monoclonal antibodies with immunocytochemical techniques to identify lymphocyte subsets and the presence of surface molecules indicative of lymphocyte activation. The majority of patients had an excess of lymphocytes in lavage and most of these cells were positively stained with the McAb recognizing the CD8 antigen (suppressor/cytotoxic type T cells). Although the proportions of CD4+ (helper type) T cells were below normal, the absolute numbers were within normal limits, thus the CD4:CD8 ratio was consistently 1:1 or less. A large proportion of the CD8+ cells displayed HLA-DR molecules (RFDR1+), interleukin-2 (IL-2) receptors (CD25+) and high concentration of CD7 antigen (RFT2+). Further analysis revealed that most CD8+ cells were CD5+ (RFT1+) yet a large proportion (20-40%) were CD5-. A majority of CD8+ cells was also CD38+ (RFT10+) and Leu7+. No clear correlation between the emergence of a raised proportion of activated CD8+ cells and diagnosed cytomegalovirus infection was found. These results demonstrate, however, that cells with the phenotype of the resident T cells of the bronchial epithelium (CD8+CD5-) emerge to the air spaces and express activation markers. This raises the intriguing paradox of an aggressive local immune response occurring in an otherwise immunosuppressed group of patients.     

T cell immunophenotypes and DR antigen expression in intravenous drug users. Relationship to human immunodeficiency virus serology

Thirty-six intravenous drug users were studied for peripheral blood mononuclear cell (PBMC) immunophenotypes and human immunodeficiency virus (HIV) serological profiles. This population has a high risk for developing HIV infection. Half (18/36) were HIV antibody (Ab) negative (-) and half were positive (+). Total T lymphocytes (CD3+ and CD2+) were not different between HIV Ab-negative and HIV-positive groups. Unactivated T(CD3+DR-) cells/mm3 were less (p = 0.003) in HIV Ab-positive patients (1,467 +/- 628) compared to HIV Ab-negative patients (2,190 +/- 695). T-helper (CD4+) cells/mm3 were also less in HIV Ab-positive patients (762 +/- 344 vs. 1,161 +/- 419, p = 0.005). The most significant difference was in activated T lymphocyte CD3+DR+) percentages where the mean was 9.6% in those HIV Ab-positive compared to 3.8% in seronegatives (p less than 0.001). Preliminary studies showed that in vitro naloxone treatment of PBMC had no effects on immunophenotypic expression except for CD3+DR+ lymphocytes, where a significant reduction was observed in the HIV Ab-positive group (p = 0.022) but not in the HIV ab-negative group. These findings suggest that in certain populations, activated T cells may be an early manifestation of HIV infection.     

Phenotypic identification of suppressor-effector, suppressor-amplifier and suppressor-inducer T cells of B cell differentiation in man

Using monoclonal anti-Leu8 antibody to isolate subpopulations of human helper/inducer (CD4+) and suppressor/cytotoxic (CD8+) T cells, we have investigated the role of these subpopulations in the regulation of B cell differentiation in the human autologous mixed leukocyte reaction (AMLR). Whereas AMLR-activated CD8+,Leu8- cells were capable of suppressing fresh AMLR cultures in the absence of fresh CD8+ cells, CD8+,Leu8+ cells suppressed only those cultures containing fresh CD8+ cells. On the other hand, CD8+,Leu8- cells became suppressor cells only when cultured in the presence of CD8+,Leu8+ cells. Finally, the development of CD8+ suppressor cells was dependent on the presence of CD4+,Leu8+ cells; CD4+,Leu8- cells were incapable of acting as suppressor-inducer cells, but have been shown previously to mediate T cell help for B cell differentiation. Thus, at least 3 phenotypically distinct subsets of T cells interact sequentially to generate suppression of B cell differentiation induced in the AMLR: CD4+,Leu8+ suppressor/inducer cells, CD8+,Leu8+ suppressor-amplifier cells and CD8+,Leu8- suppressor-effector cells.     

The mononuclear cells of human mesenteric blood, intestinal mucosa and mesenteric lymph nodes: compartmentalization of NK cells.

The proportions of T cell subsets and Leu 7+ cells and the spontaneous cell-mediated cytotoxicity (SCMC) of isolated mononuclear cells have been determined across the mesenteric vascular bed and along the intestinal mucosal-mesenteric lymph node (MLN) axis in patients undergoing abdominal surgery. Whereas the proportion of T4+ and T8+ cells were similar in simultaneously taken PVB and mesenteric venous blood (MVB), the proportion of Leu 7+ cells was higher in MVB in 16 of 17 studies (15.4 +/- 6.8%, 10.8 +/- 5.1%). Additional studies showed that the proportions of lymphocyte subsets in peripheral arterial blood are the same as those in PVB. Thus, an enrichment of Leu 7+ cells occurs across the mesenteric vascular bed. Isolated intestinal and MLN mononuclear cells contained similarly high proportions of T4+ and T8+ cells as in PVB but Leu 7+ cells made up a minority subpopulation in intestinal (1.3 +/- 0.8%) and MLN mononuclear cells (1.0 +/- 0.9%). The SCMC of intestinal and MLN mononuclear cells was low and paralleled the proportion of Leu 7+ cells. Despite the higher proportions of Leu 7+ cells in MVB, the SCMC was less than that of PVB in eight patients with inflamed intestine and not significantly different from PVB in seven patients with normal intestines. These paradoxical findings were at least in part due to inhibitory factors in mesenteric plasma. In conclusion, NK cells appear to be largely confined within the vascular system and the enrichment of Leu 7+ cells across the mesenteric vascular bed suggests that this compartmentalization may be due to differences in the traffic of lymphocyte subpopulations through the intestinal mucosa and MLN.     

The remarkable proliferation of helper T cell subset in response to autologous thyrocytes and intrathyroidal T cells from patients with graves'' disease

We have studied cellular interactions among thyrocytes, intrathyroidal T cells and peripheral blood T cells from Graves' patients. In the autologous mixed lymphocyte reaction of Graves' patients, CD4+ cells were able to proliferate vigorously against autologous non-T cells, whereas CD8+ cells responded weakly to non-T cell stimulators. Furthermore, the proliferative response of the CD4+ 2H4+ suppressor-inducer T cell subset was increased like that of the CD4+ 2H4- helper T cell subset. In contrast to peripheral blood non-T cell stimulators, thyrocytes and intrathyroidal T cells had the ability to activate the CD4+ 2H4- helper T cell subset but were not able to cause proliferation both of CD4+ 2H4+ suppressor-inducer T cell and CD8+ suppressor/cytotoxic T cell subsets. The marked reduction in proliferative responses of CD4+ 2H4+ cells and CD8+ cells could not be attributed to a difference in kinetics or altered response to variable number of stimulator cells. On the basis of these findings, it is suggested that the concentration of the helper T cell subset may be progressively increased and suppressor circuits may be unable to be activated in thyroid tissues. These abnormalities in cellular interactions may induce the excessive production of autoantibodies.     

The alternation of CD4+ cells and its subpopulations by serial monitoring of peripheral blood lymphocytes of renal allograft recipients

Immunologic monitoring for renal allograft recipients should be carried out serially and as conveniently as possible so that we can catch and treat the initial alternation of the rejection and infection. We have introduced the serial analysis of lymphocyte surface antigens of peripheral blood lymphocytes by flow cytometry for 9 cases of renal allograft recipients (3 cases of living related, 2 cases of living non-related, and 4 cases cadaver donors). In three recipients without rejection and infection, T4+(CD4+), T4+4B4+(CDw29+), T4+2H4+(CD45R+), T4+I2+(HLA-DR+), and T4+IL-2R+(CD25+) subsets showed variable processes for first 10 days and then stable processes. On primary rejection of 5 cases, activated T cell subsets such as T4+I2+ and T4+IL-2R+ subsets showed peak formations within 2 days before the rejection. Two of these 5 cases resisted a primary rejection therapy and showed a rebounding rise of these subsets. We could easily convert to OKT-3 rescue therapy and treat them successfully. We could not find out the specific alternation in the secondary rejection of 2 cases and all the infection cases. On the basis of these findings, we should serially monitor the T4+I2+ and T4+IL-2R+ subsets daily for first 2 weeks and after then 3 times a week, in order to catch the initial alternation of the primary rejection and treat its rebound successfully.     

Immunological studies of autoimmune thyroid disorders: abnormalities in the inducer T cell subset and proliferative responses to autologous and allogeneic stimulation

Various immunological parameters were investigated in patients with Hashimoto's thyroiditis (HT) and Graves' disease (GD). The total T cell numbers were significantly decreased in both diseases whether they were enumerated by E rosetting or by pan-T cell monoclonal antibodies (OKT3 and anti-Leu 1). This diminution was due to a loss in the inducer T cell subset (OKT4+/Leu 3a+) whereas the cytotoxic/suppressor T cells (OKT8+/Leu 2a+) were present at normal levels in both diseases. The B cells were significantly higher in GD patients than in controls but were not modified in HT patients. Monocyte percentages remained unchanged and DR+ cells were slightly increased in the two diseases. On the other hand, T lymphocyte responses to stimulation by autologous or allogeneic cells were significantly impaired in GD but not in HT whether cultures were performed in autologous plasma or AB serum. In addition, lymphocytes from normal subjects were unable to proliferate in auto- or allo-MLR in the presence of plasma from GD patients but they were reactive in the presence of HT plasma or AB serum. Taken together, these results suggest that the patients with autoimmune thyroid disorders exhibit a T cell imbalance within the OKT4+/Leu 3a+ subset. Moreover, this abnormality is correlated with the observation that autoreactive and alloreactive cells are defective in GD.     

Abnormal distribution of gammadelta T lymphocytes in Graves' disease and insulin-dependent diabetes type 1

There is an increasing evidence that CD3+ cells, bearing gammadelta T cell receptors representing a minor subpopulation of T cells in the peripheral blood of humans are involved in the development of autoimmunity. The aim of the present study was determination of the gammadelta T cell subpopulation levels in the peripheral blood of subjects with Graves' disease and newly diagnosed type 1 diabetes in comparison to age-matched healthy controls. The percentages of CD3+, CD8+, gammadelta TCR+CD8+, gammadelta TCR+CD8- lymphocyte subsets were measured by flow cytometry. In the peripheral blood of newly diagnosed Graves' disease patients we showed a significant decrease of gammadelta TCR+ cells and gammadelta TCR+CD8- subset content in comparison to the percentages observed in subjects after methimazole treatment and in healthy controls. We also found a significant increase of gammadelta TCR+CD8+ cells in the peripheral blood of subjects with insulin-dependent diabetes, treated with insulin for 3-6 months. The present findings confirm our previous hypothesis that gammadelta TCR+CD8+ lymphocyte subset could play a role in the pathogenesis of diabetes type 1, probably as regulatory T cells and could be induced by delivery of exogenous insulin. Our results suggest that gammadelta T cells (gammadelta TCR+CD8- subset) could also play an important role in the development of Graves' disease and that their levels are modulated by thyreostatic treatment.     

T cell interactions in active rheumatoid arthritis: insights from the human autologous mixed lymphocyte reaction as a model of T cell activation cascade.

The autologous mixed lymphocyte reaction (AMLR) represents the activation, proliferation and differentiation of T cells in response to signals from autologous non-T cells. Using monoclonal anti-Leu8 antibody to isolate subpopulations of human CD4+ and CD8+ T cells, we have investigated the role of these subpopulations in the T cell activation cascade during the course of AMLR. In normal subjects, CD4+Leu8+ cells are necessary for the initiation of the AMLR response, and sequentially lead to activation and proliferation of both CD4+Leu8- cells and CD8+Leu8+ cells. The activated CD8+Leu8+ cells, in turn, induce CD8+Leu8- cells to generate proliferation of the latter cells. Soluble mediators could be involved in the T cell activation cascade induced by the AMLR. Patients with active rheumatoid arthritis have a profound defect in the AMLR. Further analysis indicates that rheumatoid arthritis CD8+ T cells are markedly defective as responding cells in the AMLR. The impaired AMLR response by CD8+ cells cannot be reconstituted with AMLR-derived supernatants from normal T cells. The data suggest that the defective CD8+ T cell function may contribute to the pathogenesis of the disease.     

UCHL1+ (CD45RO+) ''memory'' T cells predominate in the CD4+ cellular infiltrate associated with allergen-induced late-phase skin reactions in atopic subjects.

We have previously shown that CD4+ T lymphocytes accumulated at the site of allergen induced late-phase reactions (LPR) in the skin of atopic subjects. In order to determine whether these were predominantly 'memory' or 'naive' cells, monoclonal antibodies recognizing isoforms of the CD45 common leucocyte antigen and immunocytochemical methods were used to study the composition of the T cell infiltrate. Allergen-induced late-phase skin reactions were biopsied 6, 24 or 48 h after allergen challenge. Memory (CD45RO+/UCHL1+) T cells predominated and few naive (CD45RA+/Leu18+) cells were identified. Double immunofluorescence was used to confirm that the UCHL1+ and Leu 18+ cells were CD4+ T lymphocytes. The selective recruitment of memory T cells to LPR sites is consistent with the active involvement of T lymphocytes in atopic allergic inflammation. A possible alternative explanation for apparently selective recruitment is the differential expression of endothelial adhesion molecules on memory and naive T lymphocytes.