Autoreactive T cell clones specific for class I and class II HLA antigens isolated from a human chimera.

T cell clones of donor origin that specifically react with recipient cells were obtained from a SCID patient successfully reconstituted by allogeneic fetal liver and thymus transplantation performed 10 yr ago. The majority of these clones displayed both cytotoxic and proliferative responses towards PBL and an EBV-transformed B cell line derived from the patient. In addition, these T cell clones had proliferative and cytotoxic responses towards the parental PBL, EBV cell lines, and PHA blasts. Blocking studies with anti-class I and anti-class II HLA mAbs indicated that the activity of the CD4+ T cell clones was specifically directed against class II HLA antigens of the recipient. On the other hand, the cytotoxic and proliferative responses of the CD8+ T cell clones were specific for class I HLA antigens which are ubiquitously expressed on the recipient cells. Thus, the establishment of transplantation tolerance observed in this stable human chimera is not due to the elimination of host-reactive T cells from the repertoire and suggests the presence of a peripheral autoregulatory suppressor mechanism.

Antigen recognition by MHC-incompatible cells of a human mismatched chimera.

Tetanus toxin (TT)-specific T cell clones of donor origin were obtained from a patient with severe combined immunodeficiency (SCID) successfully reconstituted by transplantation of allogeneic fetal liver and thymus cells from two different donors performed 10 yr ago. A series of these clones recognized TT in the context of "allo" class II HLA determinants expressed by recipient APC. The restriction element of two T cell clones with the HLA phenotype of the first donor (HLA-DR1,8) and one T cell clone with the HLA phenotype of the second transplant (HLA-DR3,9) was HLA-DR4 of the recipient, whereas other T cell clones derived from the second transplant recognized TT in the context of HLA-DR5 of the recipient's APC. These latter T cell clones were not able to proliferate in response to TT when autologous APC were used. These data demonstrate that recipient and donor cells having different HLA phenotypes could cooperate across the allogeneic barrier and that MHC restriction of antigen (Ag) recognition is independent from the MHC genotype of the T cells but is influenced by the environment in which the T cells mature. We also isolated T cell clones that were able to recognize processed TT presented by all allogeneic EBV cell lines tested, indicating that the Ag specificity of these clones was not restricted by a particular class II MHC molecule. The Ag-specific proliferative response of one of these clones could be blocked by anti-class II MHC mAbs. These results demonstrate that in addition to Ag recognition in the context of specific class II MHC Ags, other types of Ag-specific responses may occur in this human chimera. It is not clear whether this "allo" plus Ag recognition is the result of education of transplanted fetal cells in the host thymus. Taking into consideration our previous findings indicating that alloreactive T cell clones specific for the recipient cells could be isolated in vitro from the PBL of the same patient, our data suggest that the mechanism for deletion of self-reactive clones and the generation of MHC-restricted responses are different.

Phorbol myristate acetate: a mitogen selective for a T-lymphocyte subpopulation.

Phorbol myristate acetate (pma) is a potent mitogen for human peripheral blood lymphocytes (PBL) comparable to phytohemagglutinin (PHA) in potency. Inactivation of PHA-responsive lymphocytes by 5'-bromodeoxyuridine and light treatment left the PMA response intact and nice versa. Experiments separating lymphocytes by rosetting with sheep erythrocytes (SRBC) demonstrated that the PMA-responsive lymphocytes segregate with those that have a high affinity for SRBC to a greater than PHA- or concanavalin A (Con A)-responsive cells. These results indicate that a PMA-responsive population in human peripheral blood resides within the T-lymphocyte population and appears to have a high affinity for SRBC and to be distinct from that responding to PHA and Con A. PMA may be useful clinically to assay the size and function of the high affinity or "active" rosette population.

High levels of interleukin 10 production in vivo are associated with tolerance in SCID patients transplanted with HLA mismatched hematopoietic stem cells.

Transplantation of HLA mismatched hematopoietic stem cells in patients with severe combined immunodeficiency (SCID) can result in a selective engraftment of T cells of donor origin with complete immunologic reconstitution and in vivo tolerance. The latter may occur in the absence of clonal deletion of donor T lymphocytes able to recognize the host HLA antigens. The activity of these host-reactive T cells is suppressed in vivo, since no graft-vs. -host disease is observed in these human chimeras. Here it is shown that the CD4+ host-reactive T cell clones isolated from a SCID patient transplanted with fetal liver stem cells produce unusually high quantities of interleukin 10 (IL-10) and very low amounts of IL-2 after antigen-specific stimulation in vitro. The specific proliferative responses of the host-reactive T cell clones were considerably enhanced in the presence of neutralizing concentrations of an anti-IL-10 monoclonal antibody, suggesting that high levels of endogenous IL-10 suppress the activity of these cells. These in vitro data correlate with observations made in vivo. Semi-quantitative polymerase chain reaction analysis carried out on freshly isolated peripheral blood mononuclear cells (PBMC) of the patient indicated that the levels of IL-10 messenger RNA (mRNA) expression were strongly enhanced, whereas IL-2 mRNA expression was much lower than that in PBMC of healthy donors. In vivo IL-10 mRNA expression was not only high in the T cells, but also in the non-T cell fraction, indicating that host cells also contributed to the high levels of IL-10 in vivo. Patient-derived monocytes were found to be major IL-10 producers. Although no circulating IL-10 could be detected, freshly isolated monocytes of the patient showed a reduced expression of class II HLA antigens. However, their capacity to stimulate T cells of normal donors in primary mixed lymphocyte cultures was within the normal range. Interestingly, similar high in vivo IL-10 mRNA expressions in the T and non-T cell compartment were also observed in three SCID patients transplanted with fetal liver stem cells and in four SCID patients transplanted with T cell-depleted haploidentical bone marrow stem cells. Taken together, these data indicate that high endogenous IL-10 production is a general phenomenon in SCID patients in whom allogenic stem cell transplantation results in immunologic reconstitution and induction of tolerance. Both donor T cells and host accessory cells contribute to these high levels of IL-10, which would suppress the activity of host-reactive T cell in vivo.

The role of cysteinyl-LT(1)receptor (CysLT(1)R) in renal ischemia-reperfusion injury.

The pathogenesis of ischemia-reperfusion (I/R) injury is known to involve cytokines and particularly surface adhesion molecules, the expression of which initiates the attachment of inflammatory cells. Renal I/R injury, a clinically important problem, is an invariable consequence of renal transplantation. The problem begins at the onset of acute tubular necrosis (ATN), when the transplantation includes a long ischemic interval or by use of a cardiac arrest donor's kidney. The cysteinyl leukotriene-1 (CysLT(1)), a potent lipid mediator in allergic disease, acts through the CysLT(1)R receptor. We researched the expression of CysLT(1)R in rat renal I/R injury as well as correlations with the degree of ATN. The right kidney was harvested and the left renal artery and vein were clamped at laparotomy. The kidney was reperfused after 90 minutes of ischemia; rats were sacrificed at 0, 3, 5, 12, and 24 hours after reperfusion. CysLT(1)R expression was analyzed by immunohistochemistry. CysLT(1)R expression was observed only in endothelial cells of a normal kidney. CysLT(1)R expression was most intense on endothelial cells at 3 hours after reperfusion, and CysLT(1)R expression on endothelial cells gradually became weaker. Twelve hours after reperfusion, ATN extended throughout the ischemic kidney. Renal I/R injury gradually progressed at time after reperfusion. Several hours after the maximal CysLT(1)R expression, we observed the maximum renal I/R injury.

Effect of early initiation of highly active antiretroviral therapy on CD4 cell count and HIV-RNA viral load trends within 24 months of the onset of acute retroviral syndrome.

OBJECTIVES: The effect of starting highly active antiretroviral therapy (HAART) early after the onset of acute retroviral syndrome (ARS) on CD4 and HIV-RNA trends was studied over a 2-year follow-up period. METHODS: Four groups of HIV-infected patients stratified according to the time interval from ARS onset to HAART initiation and a control group of untreated patients were compared. RESULTS: The results indicated that the earlier the start of HAART, the faster was the rate of CD4 increase and HIV-RNA decrease. However, this difference did not seem to persist at 24 months. CONCLUSIONS: The optimal treatment strategy for HIV-infected patients needs to be explored further.

Study of cysteinyl leukotriene-1 receptor in rat renal ischemia-reperfusion injury.

Renal ischemia-reperfusion (I/R) injury is a major cause of renal transplant dysfunction. Recent studies of I/R injury have focused on the function of neutrophils, the mechanisms of action of inflammatory cytokines, and oxygen free radicals, as well as other mediators. However, few reports address the cysteinyl leukotriene-1 receptor (CysLT1R), an important mediator of bronchial asthma in human beings. We examined the expression of CysLT1R in rat renal I/R injury. At laparotomy, the right kidney was harvested and the left renal artery and vein were clamped. The kidney was reperfused after 90 minutes of ischemia, and the rats were killed after 0, 3, 5, 12, or 24 hours. Expression of CysLT1R analyzed at immunohistochemistry was observed only in endothelial cells in nonischemic kidney. At 0 to 3 hours after reperfusion, CysLT1R expression on endothelial cells gradually became stronger, being most intense at 3 hours after reperfusion. Twelve hours after reperfusion, necrosis extended throughout the ischemic kidney; nearly all of the tubular epithelial cells were destroyed. At 3 to 12 hours after reperfusion, CysLT1R expression gradually became weaker on endothelial cells. At 24 hours after reperfusion, CysLT1R expression was almost at the level of that in nonischemic kidney. Expression of CysLT1R was noted in a rat model of renal I/R injury. Several hours after the maximal CysLT1R expression, we observed the maximum renal I/R injury. These results may suggest a relationship between the CysLT1R and renal I/R injury.

Cooperation between major histocompatibility complex mismatched mononuclear cells from a human chimera in the production of antigen-specific antibody.

Fetal liver and thymus transplantation can be successfully employed for the treatment of severe combined immunodeficiency disease. In virtually all cases, donor and recipient cells are HLA mismatched. In a patient suffering from a severe combined immunodeficiency disease, full immunological reconstitution was obtained after fetal liver and thymus transplantation. HLA typing revealed that the patient's T cells were of donor origin, while the B cells and monocytes were of host origin. Despite this complete HLA mismatch, the patient was found to mount a subnormal to normal antibody response in vivo. This finding is in contrast with the concept that antigen recognition by T cells is major histocompatibility complex (MHC) restricted. To define the mechanism responsible for this in vivo antibody response, antibody production by peripheral blood mononuclear cells from the patient was tested in vitro after in vivo booster. The in vitro anti-tetanus toxoid antibody production was similar to that of the control group. In addition, specific proliferative responses to tetanus toxoid were obtained. Immunoglobulin allotype determination showed that antibodies were synthetized by host B cells. The results of the present study indicate that transplanted T lymphocytes and recipient cells cooperate despite complete HLA mismatch.

Chimerism and tolerance to host and donor in severe combined immunodeficiencies transplanted with fetal liver stem cells.

We have studied the peripheral T cell repertoire of two patients with severe combined immunodeficiency who were successfully treated with human histocompatibility leukocyte antigen (HLA)-mismatched fetal liver stem cell transplantation. The patients presented a split chimerism. T cells were of donor origin, whereas the B cells/monocytes were of the host phenotype. Interestingly, the natural killer (NK) cells in one patient were donor derived and in the other patient of host origin. The NK cells were functional but did not have antihost or donor reactivity. Despite the HLA mismatch between donor and host cells, complete tolerance was achieved in vivo, and a specific unresponsiveness of peripheral blood mononuclear cells from both patients toward the host cells was demonstrated in vitro. Nevertheless, we could isolate T cell receptor (TCR)alpha beta, CD4+ or CD8+, T cell clones specifically reacting with HLA class I and II molecules of the host. The CD4+ host-reactive T cell clones from both patients produced interleukins 2 and 5, interferon-gamma, granulocyte/macrophage colony-stimulating factor but are specifically defective in interleukin 4 production. The frequencies of CD8+ host-reactive T cells were high, and were in the same range as those observed for CD8+ alloreactive T cells. In contrast, no donor-reactive CD8+ T cells or host or donor-reactive TCR gamma delta + T cells were detected. These data indicate that, after fetal stem cell transplantation, donor-reactive, but not host-reactive cells, are deleted from the T cell repertoire. Therefore, a peripheral mechanism of suppression or clonal anergy, rather than clonal deletion, is involved in maintaining in vivo tolerance toward the host.

Impact of immunosuppression on improvement of results in clinical pancreas transplantation.

Since November 1975, 103 pancreas transplantations have been performed in 97 insulin-dependent diabetic patients. Pancreas and kidney were grafted simultaneously in 84 patients (plus 1 double retransplantation). Eighty-nine pancreas grafts were prepared by duct obstruction with neoprene, and 14 were pancreaticoduodenal grafts with enteric diversion in a Roux-en-Y loop. Five immunosuppressive protocols were subsequently used. With the latest protocols, patient and pancreas survival improved to 93 and 72% at 1 yr, respectively. The improvement in graft survival appeared to be particularly related to the reduction of the number of pancreas grafts lost in rejection. The patients treated with the last protocols, including cyclosporin A (CsA) and only low doses of steroids, showed a better glucose tolerance after provocative tests. Pancreas-graft function did not appear to be influenced by CsA treatment.

Kidney-graft survival in simultaneous kidney-pancreas transplantation.

Patient and kidney survival rates were compared between 69 diabetic patients undergoing simultaneous kidney-pancreas transplantation (group 1) and 723 nondiabetic patients undergoing kidney transplantation (group 2). The patients were treated with different immunosuppressive regimens over the years: steroids plus antilymphocyte globulin (ALG) plus azathioprine (Aza); cyclosporin A (CsA) plus ALG; steroids plus ALG plus Aza, replacing Aza 1 mo posttransplantation; or low doses of steroids plus CsA plus Aza. One-year kidney survival rates with the different regimens were 50, 42, 54, and 76%, respectively, in group 1 and 71, 74, 78, and 84%, respectively, in group 2. Patient survival was 60, 57, 71, and 86%, respectively, in group 1 and 93, 95, 94, and 96%, respectively, in group 2. Differences between the two groups were statistically significant for the first three protocols but not for the one used in this study. In group 1, 38 patients (55%) had a functioning kidney graft, whereas 15 (21%) lost their kidney to rejection. Between these two patient categories, there was no significant difference in age, sex, duration of diabetes, time on dialysis, blood transfusion number, HLA immunization, or HLA matching. Thus, since 1984, kidney-graft survival has not been inferior in diabetic patients. This improvement is mainly due to a decreased mortality related to better patient preparation and improvement in immunosuppression.

Islet cell autoimmunity in type I diabetic patients after HLA-mismatched pancreas transplantation.

The aim of this study was to investigate a possible reenhancement of islet cell autoimmunity in type I (insulin-dependent) diabetic patients who received HLA-mismatched pancreas transplants from cadaveric donors and who underwent generalized immunosuppression. Circulating islet cell antibodies (ICA) and complement-fixing ICAs (CF-ICAs) have been tested at 1, 2, 3, 6, and 12 mo and at least once a year posttransplantation in 23 recipients of 25 transplants (22 simultaneous with kidney, 2 retransplants, 1 isolated; 23 segmental neoprene injected, 2 whole with enteric drainage). Patients were aged 35.3 +/- 1.9 yr with a duration of diabetes of 20.6 +/- 1.1 yr. Immunosuppression consisted of double or triple association of azathioprine, cyclosporin, and prednisone with or without temporary antilymphocyte globulins. The number of HLA-A and HLA-B compatibilities was none in 8 patients, one in 12 patients, two in 4 patients, and three in 1 patient. The mean follow-up was 4.0 +/- 0.4 yr/patient (range 0.4-7.2). ICAs were positive pretransplantation in 2 of 25 patients and reappeared 1-42 mo posttransplantation in another 7. In 6 patients, CF-ICAs were also positive. In 7 of 9 ICA+ patients the pancreas transplant failed; in 1 patient this occurred 4 mo before ICA reappearance, and in 6 patients it occurred 2-35 mo after the first detection of ICAs. Pancreas-transplant failure was significantly associated with the positivity for ICAs (P less than .05) and particularly for CF-ICAs (P less than .005). ICA positivity was transitory in 4 patients (2-27 mo) and persistent in the remaining 5 (up to 61 mo).(ABSTRACT TRUNCATED AT 250 WORDS)

Induction of transplantation tolerance in humans using fetal cell transplants.

When engrafted with donor stem cells and lymphoid cells, patients develop transplantation tolerance to donor antigens. We analyzed the mechanism of tolerance induction in immunoincompetent recipients whose immunity has been reconstituted by transplantation of mismatched stem cells. Seven infants or human fetuses received fetal liver transplants as a treatment for severe combined immunodeficiency disease. After reconstitution of immunity by lymphocytes developed from donor stem cells, T-cell clones were produced and analyzed. Because donors and recipients were HLA mismatched, it was easy to demonstrate the donor origin of the T-cell clones. These clones were shown to have developed tolerance to histocompatibility antigens of the stem cell donor via a process of clonal deletion (probably as a result of contact with donor-derived macrophages and dendritic cells). They were also tolerant to histocompatibility antigens of the host but through a different mechanism: many clones recognized these antigens but had no detrimental effect on the target cells exhibiting host antigens, either in vitro or in vivo. Clonal anergy was therefore the cause of this tolerance to host determinants, resulting in a lack of graft-versus-host disease and of autoimmunity. The contact between developing T cells of donor origin and host epithelial cells within the host thymus may explain this colonal anergy. It should be noted that all patients had high serum levels of interleukin-10, which might have contributed to the persistent engraftment and tolerance.

Human interleukin-10 transduced fetal liver stem cells prolong survival of mouse skin and heart allografts.

Interleukin (IL)-10 regulates immune responses, acting as a suppressive cytokine by inhibiting the synthesis of Th1 cytokines, such as IL-2 and interferon (IFN)-gamma. It also strongly down-regulates major histocompatibility complex (MHC) class II determinants on antigen presenting cells (APC). On the other hand, long-term tolerance is well correlated with the persistence of a peripheral microchimerism. In this study, we investigated the synergistic effect of human IL-10 (huIL-10) and hematopoietic microchimerism for the induction of long-term tolerance. Irradiated Balb/c mice (H-2d) were used as recipients (fetal liver stem cells [FLSC], skin and heart) and C57BL/6 (H-2b) mice were used as donors of FLSC, skin and heart. Recipients were simultaneously transplanted with the heart, the skin and with huIL-10 gene-transduced FLSC. Microchimerism was checked using fluorescent flow cytometry, huIL10 production using enzyme-linked immunosorbent assay (ELISA), and graft survival was evaluated by daily observation. Significant level of huIL10 (up to 900 pg/mL) was detected for more than 2 weeks in the serum of mice that underwent transplantation. Four weeks after the FLSC injection, microchimerism was identified in the recipient lymphoid organs (spleen, thymus, and bone marrow) by the presence of donor cells (H-2b). Finally, in the group of mice treated with huIL-10 gene-transduced FLSC, skin allografts survived for 18.9 +/- 1.8 days compared with 9.5 and 9.6 days in the groups of mice treated with nontransduced FLSC or huIL-10 alone, respectively. The same pattern for heart allograft survival was observed. HuIL-10 transduction of donor hematopoietic stem cells resulted in production of huIL-10, cell engraftment, and chimerism. Although full tolerance was not obtained, specific and highly significant (P < .001) prolongation of the survival of donor heart allografts with (more than 2-fold compared with nontreated groups) was observed. The infiltration of the transplanted heart and its late rejection demonstrate that stem cells transduced with huIL-10 gene induce "prope" tolerance in this model.

[Kaposi's sarcoma and organ transplantation: 22 cases]. / Maladie de Kaposi et transplantation d'organes: 22 cas.

BACKGROUND: The discovery of the Human Herpes virus 8 (HHV8) improved our knowledge of the pathogenesis of Kaposi's sarcoma. After organ transplantation, Kaposi's sarcoma exhibits distinctive features compared with other forms of the disease. PATIENTS AND METHODS: We report 22 cases of post-transplant Kaposi's sarcoma (12 kidneys, 2 kidney-pancreas, 6 livers and 2 hearts). The aim of this retrospective study was to analyze clinical and virological characteristics in these transplant patients and to specify the frequency of HHV8 seroconversions in this population. RESULTS: Twenty-one patients showed cutaneous lesions and 9 had visceral involvement. HHV8 serology was positive in 16/20 patients at transplantation and in 21/22 cases at the time of Kaposi's sarcoma diagnosis. Most cases corresponded to viral reactivations whereas seroconversions occurred in 2 cases and may have been linked to viral transmission by the graft. Treatment led to recovery in 68p. 100 of the cases. Two heart-transplant patients died from their disease. We included in our series two cases of re-transplanted patients without recurrence of Kaposi's sarcoma and one case of familial Kaposi's sarcoma. DISCUSSION: Seroconversions after transplantation emphasize the interest of systematic screening of HHV8 serology in transplant recipients and their donors.

Gene transfer of anti-gp41 antibody and CD4 immunoadhesin strongly reduces the HIV-1 load in humanized severe combined immunodeficient mice.

OBJECTIVE: To study the anti-HIV-1 effects of the delivery of anti-gp41 monoclonal antibody (mAb) and soluble CD4 (sCD4) immunoadhesin by genetically modified cells in HIV-1-infected, humanized severe combined immunodeficient (SCID) mice. DESIGN: The complementary DNA of mAb 2F5, an anti-HIV-1 gp41 antibody, and of sCD4-IgG chimeric immunoadhesin were transferred into 3T3 cells using Moloney murine leukaemia virus vectors. The cells were then incorporated into a collagen structure called the neo-organ, which allowed the continuous production of the therapeutic molecules. METHODS: The antiviral effects in vivo of 2F5 or sCD4-IgG or both compounds were evaluated in neo-organ-implanted SCID mice that were grafted with human CD4 CEM T cells and challenged with HIV-1 Lai or MN. RESULTS: In SCID mice implanted with 2F5 neo-organs, antibody plasma levels reached 500-2000 ng/ml. Viral loads after HIV-1 challenge were significantly reduced in neo-organ-implanted HIV-infected mice. Although 29 x 10(7) and 13 x 10(8) HIV-1-RNA copies/ml were detected at 12 days in the controls (mice injected with Lai and MN, respectively) less than 16.5 x 10(3) HIV-1-RNA copies/ml were observed in all implanted mice injected with either Lai or MN. The intracellular viral load was also reduced in CD4 cells recovered from the implanted mice. Comparable antiviral effects were obtained with CD4-IgG neo-organs. CONCLUSION: Our results confirm the anti-HIV properties of 2F5 and sCD4-IgG continuously produced in vivo after ex-vivo gene therapy in SCID mice.

Experimental gene therapy: the transfer of Tat-inducible interferon genes protects human cells against HIV-1 challenge in vitro and in vivo in severe combined immunodeficient mice.

OBJECTIVES: To evaluate in vitro and in vivo a strategy for gene therapy for AIDS based on the transfer on interferon (IFN)-alpha, -beta and -gamma genes to human cells. DESIGN: Human U937 promonocytic cells were stably transfected with Tat-inducible IFN expression vectors conferring an antiviral state against infection with HIV. METHODS: Transfected cells were either infected by HIV-1 in vitro or transplanted into severe combined immunodeficient (SCID) mice for an HIV challenge in vivo. RESULTS: U937 cell lines stably carrying IFN transgenes under the positive control of the HIV-1 Tat protein were highly resistant to HIV-1 replication in vitro. This antiviral resistance was associated with a strong induction of IFN synthesis immediately following the viral infection. HIV-1 proteins were found to be specifically trapped within the genetically modified cells. In contrast, all IFN-U937 cells permitted full HIV-2 replication. Transfected cells injected into SCID mice and challenged against HIV-1 were strongly resistant to infection when cells were transduced with IFN-alpha of IFN-beta genes. However, IFN-gamma-transfected cells permitted HIV-1 infection in vivo despite the induction of a high level of IFN-gamma secretion. The quantity of proviral DNA was 10(5)-fold lower in IFN-alpha- or IFN-beta-transfected U937 cells collected from these SCID mice than that in non-transfected cells. CONCLUSIONS: Our results substantiated the validity of a strategy, bases on the transfer of HIV-1-inducible IFN-alpha or IFN-beta genes, to confer antiviral resistance to human cells.

Fat distribution evaluated by computed tomography and metabolic abnormalities in patients undergoing antiretroviral therapy: preliminary results of the LIPOCO study.

BACKGROUND: Fat distribution abnormalities have been reported in patients treated with various antiretroviral drug regimens. The LIPOCO study is an ongoing observational study of unselected HIV-infected patients which aims to better characterize such disorders and their metabolic correlations. METHODS: Cross-sectional analysis of data collected at baseline in the first 154 male patients included. Investigators divided patients into four predetermined clinical categories of fat distribution: lipoatrophy, obesity, mixed condition and normal. Body composition (tetrapolar bioelectrical impedance analysis and skinfold thickness), fat distribution [computed tomography (CT) scan], plasma glucose and insulin concentrations both fasting and during an oral glucose tolerance test and endocrine and lipid profile were measured and compared between the four groups. RESULTS: Patients in the lipoatrophy group had significantly decreased abdominal and mid-thigh subcutaneous fat area values and elevated levels of plasma triglycerides. Patients in the obese and mixed groups had significantly increased intra-abdominal fat area values and elevated levels of plasma insulin and C-peptide. The CT scans identified some patients with isolated subcutaneous fat accumulation but no other alterations in fat distribution and no insulin resistance. Visceral adipose tissue measured by CT scan was positively correlated with fasting insulin and the sum of insulin levels (P < 0.0001). Fasting insulin as well as the sum of insulin levels were negatively correlated with the delta HIV-RNA (log(10)). In a multivariate logistic regression model, the use of stavudine significantly correlated with fat wasting in both nucleoside reverse transcriptase inhibitor and protease inhibitor groups: odds ratio (OR), 413 [95% confidence interval (CI), 5.2-999; P = 0.0068] and OR, 2.08 (95% CI, 0.92-7.0; P = 0.058) respectively, when compared with the use of zidovudine. Neither lamivudine or didanosine use, nor the use of protease inhibitors were significantly associated with fat distribution abnormalities or fat wasting. CONCLUSIONS: These preliminary results suggest that three major types of fat distribution abnormalities may occur in isolation or in association in HIV-infected patients undergoing active antiretroviral therapy: a fat depletion or 'lipoatrophy' syndrome which might be related to the use of stavudine; a mixed or fat redistribution syndrome related to an unusual side-product of effective virus control; and a subcutaneous adiposity syndrome reflecting increase in caloric intake.

A syndrome of peripheral fat wasting (lipodystrophy) in patients receiving long-term nucleoside analogue therapy.

OBJECTIVE: To compare body composition, body fat distribution and insulin secretion in patients taking nucleoside reverse transcriptase inhibitor (NRTI) therapy. DESIGN AND SETTING: Cross-sectional study in three French AIDS clinical centres. PATIENTS: Forty-three HIV-infected patients on long-term NRTI therapy including stavudine (n = 27) or zidovudine (n = 16) and 15 therapy-naive HIV-infected patients (control group). MAIN OUTCOME MEASURES: Fat wasting was assessed by physical examination and body composition by bioelectrical impedance. Regional fat distribution was estimated using caliper measurements of skinfold thickness at four sites and evaluated by computed tomography at abdominal and mid-thigh level. Fasting glucose, insulin, C-peptide, triglyceride, cholesterol, free fatty acid, testosterone, follicle stimulating hormone, luteinizing hormone, cortisol levels, CD4 cell count and HIV viral load were determined. Daily total caloric and nutrient intake were evaluated. RESULTS: The zidovudine group and the control group had similar body composition and regional fat distribution. Stavudine therapy was associated with a significantly lower percentage of body fat (12.9% versus 15.2% in the zidovudine group; P < 0.05), markedly decreased subcutaneous to visceral fat ratio (0.90 +/- 0.63 versus 1.92 +/- 1.34, P < 0.01) and higher mean intake of fat and cholesterol (P < 0.01). Fasting plasma glucose, insulin and C-peptide levels were similar among the three groups. Triglyceride levels were significantly higher in the stavudine group than in the controls (P < 0.05), but did not differ between the stavudine and the zidovudine group or between the zidovudine and the control group. Free fatty acids tended to be higher in the stavudine group but the difference did not reach statistical significance. Lipodystrophy was observed clinically in 17 (63%) patients taking stavudine, and in three (18.75%) patients taking zidovudine after a median time of 14 months. The relative risk of developing fat wasting was 1.95 in the stavudine group as compared with the zidovudine group (95% confidence interval, 1.18-3.22). Five out of 12 patients had a major or mild improvement in their lipodystrophy after stavudine was discontinued. CONCLUSION: Lipodystrophy may be related to long-term NRTI therapy, particularly that including stavudine.