PubMed Health⌕ Search

Biomedical subjects

E Racadot

Publications and source records attributed to E Racadot.

At least 73 records · Page 4Linked to original sources

[Therapeutic use of a monoclonal, anti-CD4 antibody in refractory rheumatoid polyarthritis. Preliminary results].

Ten patients (6 women and 4 men), with a group mean age of 65 years, defined as severe and with a mean follow-up period of 9 years and refractory to conventional treatments, were treated with monoclonal anti-CD4 antibodies in an open study. The monoclonal antibodies, of murine origin, were administered by intravenous route for ten consecutive days at a dose of 10 mg (1 patient), 15 mg (2 patients) or 20 mg (7 patients). Local and systemic tolerability were excellent. Clinical improvement was rapid (pain, morning stiffness, Ritchie index, p = 0.005 between D0 and D15), as was the paraclinical improvement (C-reacting protein, p = 0.008), although without achieving complete remission. The outcome revealed that the effect was more prolonged in patients treated with 20 mg per day than in the others, suggesting a dose-effect relationship. The improvement obtained may persist for more than 9 months in some patients. No significant change in immunological parameters was found at the end of the treatment (lymphocyte populations, immunoglobulins, complement). Only 2 out of 10 patients developed anti-mouse antibodies. As a result of its excellent tolerability and rapid effectiveness, this antibody appears to offer fresh therapeutic prospects in rheumatoid arthritis.

Aged↗

Treatment of corticosteroid resistant acute graft-versus-host disease by in vivo administration of anti-interleukin-2 receptor monoclonal antibody (B-B10)

In a multicenter pilot study, 32 patients showing steroid-resistant acute graft-versus-host disease (GVHD) were treated by in vivo administration of anti-interleukin-2 (IL-2) receptor monoclonal antibody (MoAb B-B10). Twenty-three patients received marrow from HLA-matched related donors, four from matched unrelated donors and five from partially matched related donors. The overall grade of GVHD was II in 16 patients, III in two, and IV in five. Five milligrams of B-B10 MoAb was infused in bolus daily for 10 days and then every second day for a further 10 days in an attempt to reduce GVHD recurrence. No clinical side effects were noted during the B-B10 treatment period. A complete response (CR) acute GVHD was achieved in 21 patients (65.6%). Six patients (18.7%) showed partial improvement (PR) and 5 patients (15.6%) no response (NR). A significant factor associated with GVHD response was the delay between the onset of the GVHD and the first day of B-B10 infusion. The earlier B-B10 was introduced, the greater the probability of CR (P = .03). There was no correlation between the serum B-B10 level and GVHD response (P = .69). There was, however, a significant correlation between the clinical response and the B-B10 kinetics as a function of time: serum B-B10 levels attained a plateau level more rapidly in the CR group than in the PR/NR group. Among the 26 complete and partial evaluable responders, GVHD recurred in 10 cases (38.4%). Host anti-B-B10 MoAb immune response occurred in only one (7.1%) of the 14 patients analyzed. Fourteen of the 32 patients (43.7%) are currently alive between 2 and 14 months after GVHD treatment with B-B10 was completed.

Adolescent↗

[Study of the bronchoalveolar lavage in ankylosing spondylarthritis].

The study of the broncho-alveolar lavage (BAL) has been carried out in 15 consecutive (13 B27) ankylosing spondylarthritis (AS), compared to 17 test subjects. There is no modification of the number of cells, of the percentage of lymphocytes, of the CD4/CD8 ratio, of the beta-2-microglobulin or the conversion enzyme in the BAL liquid between the AS group and the test group. The IgA level of the BAL is lower and the IgA deposits in the bronchial mucosa are more frequent in the AS group (but not in a significant way). Unlike other inflammatory diseases, it seems that there is no subclinical alveolitis in the course of AS.

Adult↗

Pyoderma gangrenosum in an allogeneic bone marrow transplant recipient.

We present the case of a 15-year-old boy who developed facial pyoderma gangrenosum following an allogeneic bone marrow transplantation for the treatment of a 'blast' crisis developing in the course of chronic myelogenous leukaemia. The lesion appeared 7 months before any evidence of relapse. The discussion is focused on both the presentation of pyoderma gangrenosum associated with myelo-proliferative disorders and its pathogenesis via the underlying immunosuppression.

Adolescent↗

[Natural cytotoxic function and ankylosing spondylitis].

Natural Killer (NK) cell function was evaluated in 28 ankylosing spondylitis (AS) patients (21 B27 positive), at one hand by the use of a Leu7 (HNK-1) monoclonal antibody, at the other hand by spontaneous cytotoxicity against a K562 cell line (preincubated with a fluorogenic substrate) evaluated by a flow cytometric assay. There is no difference in NK cell activity neither between AS patients and controls nor between B27 positive and negative AS. The study brings no evidence for a NK function control by the B27 gene. There is no correlation between NK activity and each of the other parameters investigated (ESR, B2m, IgA, Leu7, T4/T8). At the opposite, NK activity is significantly decreased (p = 0,006) in AS patients under NSAIDs treatment compared with non treated patients. NSAIDs rather enhance NK activity, the decrease observed in the present study could be due to evolution of the disease itself, and may be a pathogenetic factor contributing to remaining of bacterial antigens according to the current hypothesis of the disease's aetiology.

Adult↗

[Immunomodulation by in vivo monoclonal antibodies during bone marrow grafts: parameters of biological monitoring].

Fifteen patients undergoing allogeneic BMT were given monoclonal antibodies (MAb). One patient received OKT3 and 5 patients an anti-LFA1 MAb to prevent the graft rejection, 7 patients received a CD5-CD8 combination for treatment of acute GvHD and 2 patients received a CD8 MAb to overcome graft rejection. One autografted patient was administered with a CD8 MAb for an hypoplasia associated with a CD8+ lymphocytosis. Biologic monitoring associated the evaluation of serum MAb level, the analysis of target cell depletion and the detection of anti MAb antibodies. Except for OKT3, the MAb dosage had to be adjusted so that the recipients remained in antibody excess as determined by in vitro monitoring. Although the patients treated with CD5-CD8 or CD8 alone exhibited complete coating of reactive cells we did not observe a complete depletion of these populations.

Antibodies, Monoclonal↗

Cellular immune response in Echinococcus multilocularis infection in humans. I. Lymphocyte reactivity to Echinococcus antigens in patients with alveolar echinococcosis.

The involvement of cellular immunity in alveolar echinococcosis (AE) due to E. multilocularis is strongly suggested by the intense granulomatous infiltration observed around the hepatic parasitic lesions, and a progressive decrease of specific cellular immunity has been described in murine AE. However, specific cellular immunity against E. multilocularis has never been documented in human AE. The reactivity to phytohaemagglutinin (PHA) and E. multilocularis antigens of peripheral blood mononuclear cells (PBMC) from 48 patients with AE and 35 control subjects was evaluated by incorporation of 3H-methylthymidine into DNA. A sequential measurement of the proliferative response of PBMC was performed in 20 patients 2 years later, and again in five of them 4 years after the first determination. After stimulation by PHA, the mean proliferation index (PI) of the patients with AE was somewhat higher than that observed in the uninfected controls, but the difference was not significant. The PI obtained with E. multilocularis antigens was higher than the threshold value in all the patients but one, and in five control subjects. The difference between the PI values in the patients with AE and those obtained in the control subjects was highly significant. There was no correlation between the lymphocyte proliferation indices and the specific antibodies assessed using the Em 2-ELISA, or the volume of the parasitic lesions. All the five 'positive' control subjects were living in areas endemic for AE. A previous contract of these subjects with E. multilocularis in the past, followed by a spontaneous elimination of the parasite is possible. The long-term persistence of lymphocyte reactivity to parasite antigens was emphasized by the results of the follow-up of 20 patients with AE: reactivity of PBMC decreased progressively but persisted more than 4 years after complete resection of the parasitic lesions in the patients who underwent a radical surgical procedure. Conversely, an increase in the PI was shown to be usually associated with a progression of the liver lesions.

Adult↗

Marrow transplantation from HLA non-identical family donors for the treatment of leukaemia: a pilot study of 15 patients using additional immunosuppression and T-cell depletion.

Fifteen patients with high-risk leukaemia were given T-cell depleted marrow transplants from HLA non-identical related donors. They were treated with a combination of total body irradiation (TBI), high-dose cytosine arabinoside (Ara-C) and high-dose melphalan in an attempt to prevent a host-versus-graft reaction. Antilymphocyte globulins were given prior to transplantation for additional immunosuppression to 13 patients and in-vivo monoclonal antibody anti-human LFA1 to two. Engraftment and chimaerism assessed by HLA typing were achieved in 14 patients. Seven developed acute graft-versus-host disease (two fatal), one failed to engraft. Six patients died in complete remission from cytomegalovirus (CMV) interstitial pneumonitis and three remain alive in complete remission 2, 3 and 13 months after transplant. We conclude that aggressive immunosuppression allows for sustained engraftment of T-cell depleted HLA non-identical marrow. The incidence and severity of GVHD are acceptable and CMV pneumonitis remains the major problem.

Adolescent↗

Preclinical studies of a panel of 12 monoclonal antibodies in view of bone marrow purging in acute lymphoblastic leukemia.

We analysed the optimal conditions for autologous bone marrow purging using complement binding monoclonal antibodies (mAbs). Twelve mAbs belonging to four clusters (CD9, CD10, CD19, CD24), alone or combined were evaluated by using direct cytotoxicity and clonogenic assays. We observed the following data: (1) optimal cytotoxicity was reached with doses of 1-10 micrograms mAbs for 10(7) cells, (2) the concentration of the cell suspension had to be below 3 X 10(7)/ml, (3) combinations of mAbs were more effective than a single mAb treatment, (4) in the case of an IgM isotype, there seems to be a clear dissociation between the amount needed for optimal toxicity and that for antigenic saturation measured by cytofluorometry.

Antibodies, Monoclonal↗