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1.
BMC Immunol ; 17(1): 34, 2016 Sep 29.
Article in English | MEDLINE | ID: mdl-27687879

ABSTRACT

BACKGROUND: Although Hizentra is indicated for immunoglobulin replacement therapy in patients with primary and secondary immunodeficiencies, phase III trials have focused on patients with primary immunodeficiencies. In this 9-month, real-life, prospective, non-interventional, longitudinal, multicenter study of patients with primary and secondary immunodeficiencies in France, treatment modalities (primary endpoint), efficacy, safety, tolerability, quality of life, and treatment satisfaction were evaluated using descriptive statistics. RESULTS: Starting in January 2012, 117 patients were enrolled (99 adults, 18 children). Secondary immunodeficiencies were present in 48.7 % of patients. At follow-up, injections were administered every 7 days in 92.2 % of patients. Nine patients (7.8 %) were taking Hizentra every 10-14 days. The median dose of Hizentra administered was 0.1 g/kg/injection. Fifty-six patients were administered doses <0.1 g/kg/injection and 13 patients were administered doses >0.2 g/kg/injection. Mean trough IgG titers were 9.0 ± 3.3 g/L (median 8.3 g/L). The mean yearly rate of infection was 1.2 ± 1.9. Mean scores on the Short Form-36 physical and mental component summaries were 46.3 ± 10.0 and 46.6 ± 9.3, respectively. Scores on the Treatment Satisfaction Questionnaire for Medication ranged from 69.9 ± 19.9 to 88.3 ± 21.2 depending on the domain. Treatment with Hizentra was well tolerated. No single drug-related systemic reaction occurred in more than one patient and few local reactions were reported (n = 5). CONCLUSIONS: Under real-life conditions and in a cohort that included patients with primary and secondary immunodeficiencies, treatment with Hizentra was effective and well tolerated and patients were generally satisfied with the treatment.

2.
Semin Thromb Hemost ; 25 Suppl 2: 25-8, 1999.
Article in English | MEDLINE | ID: mdl-10440419

ABSTRACT

Clopidogrel is extensively metabolized, as evidenced by the absence of detectable amounts of unchanged clopidogrel in plasma samples in most clinical trials. The major circulating compound is the inactive carboxylic acid derivative SR26334, and information on the absorption and elimination of clopidogrel after oral administration is derived from the pharmacokinetics of this metabolite. Single-dose pharmacokinetics of SR26334 were investigated in a randomized, dose-proportionality study comparing single 50, 75, 100, and 150 mg oral doses of clopidogrel administered to 12 subjects. Multiple-dose pharmacokinetics of SR26334 were primarily derived from a study carried out in 18 subjects treated with clopidogrel 75 mg once daily for 14 days. Further data on multiple-dose pharmacokinetics were provided by the results of a long-term study carried out in a group of 35 subjects who received clopidogrel 75 mg once daily for 12 weeks. All subjects were healthy male volunteers and, in all cases, clopidogrel was taken in the morning after an overnight fast. The mean Cmax values (+/-SD) for SR26334 following single doses of 50, 75, 100, and 150 mg were 1.6+/-0.30 mg/L, 2.9+/-0.68 mg/L, 3.1+/-0.94 mg/L, and 4.9+/-1.22 mg/L, respectively. The ANOVA performed on dose-normalized Cmax showed no statistically significant dose effect, demonstrating a dose-proportional increase of Cmax in this range of clopidogrel doses. The urinary excretion of SR26334 was low-2.2 to 2.4% of the dose administered-and Cl(r-2-24) remained virtually constant at all four doses. Median T(max)(0.8-1.0 hour) and mean plasma t1/2 (7.2-7.6 hours) values were not significantly different between doses. Following repeated dosing with clopidogrel 75 mg, mean (+/-SD) C(trough) values (values before dosing) for SR26334 at steady state ranged from 0.8+/-0.04 mg/L to 0.11+/-0.07 mg/L. These values are similar to those observed during the 12-week administration of clopidogrel indicating that steady-state values are reproducible and that the esterasic biotransformation of clopidogrel into its carboxylic acid metabolite remains constant over a number of months of treatment.


Subject(s)
Platelet Aggregation Inhibitors/administration & dosage , Platelet Aggregation Inhibitors/pharmacokinetics , Ticlopidine/analogs & derivatives , Administration, Oral , Adolescent , Adult , Bleeding Time , Carboxylic Acids/administration & dosage , Carboxylic Acids/blood , Carboxylic Acids/pharmacokinetics , Clopidogrel , Dose-Response Relationship, Drug , Humans , Male , Platelet Aggregation Inhibitors/blood , Ticlopidine/administration & dosage , Ticlopidine/blood , Ticlopidine/pharmacokinetics
3.
Thromb Haemost ; 79(6): 1162-5, 1998 Jun.
Article in English | MEDLINE | ID: mdl-9657442

ABSTRACT

Venous thromboembolism may be efficiently treated by one single daily administration of a high dose of low molecular weight heparin (LMWH). The present study investigates if the physiological deterioration of renal function associated with normal aging or the presence of an acute venous thromboembolism influences the pharmacodynamic pattern of the anti-factor Xa and anti-thrombin activities. Three groups of 12 subjects were investigated. The first 2 groups were composed of healthy volunteers differing by age (25 +/- 4 and 65 +/- 3 yrs) and creatinine clearance (114 +/- 15 and 62 +/- 6 ml x min(-1)). The third group was composed of patients hospitalized for deep vein thrombosis, having a mean age of 65 +/- 11 yrs and creatinine clearance of 76 +/- 8 ml x min(-1). Nadroparin was administered subcutaneously once daily at the dose of 180 anti-factor Xa IU.kg(-1) for 6 to 10 days. Serial sampling on day 1 and on the last day of administration (day n) allowed the pharmacodynamic parameters of the anti-factor Xa and anti-thrombin activities to be compared at the beginning and at the end of the treatment. The main findings were the following: (1) After repeated administration, a significant accumulation of the anti-factor Xa activity was observed in the healthy elderly and in the patients but not in the healthy young subjects (accumulation factor: 1.3). There was no evidence of accumulation of anti-thrombin activity; (2) There were significant correlations between the clearance of creatinine and the clearance of the anti-factor Xa activity but not with that of the anti-thrombin activity; (3) In the patients, the clearance of the anti-factor Xa and of the anti-thrombin activities were 1.4 and 2 times higher respectively than those calculated in the healthy elderly; (4) The mean ratio of the of anti-factor Xa and anti-thrombin clearances was close to 2 in the healthy subjects but equal to 5.4 in the patients. These results suggest that the mechanisms involved in the clearance of polysaccharide chains which support the anti-thrombin activity are different from those of the anti-factor Xa activity and that the enhanced binding properties of plasma proteins to unfractionated heparin reported in patients presenting an acute venous thromboembolism also exists for LMWH, predominantly for the anti-thrombin activity.


Subject(s)
Aging/metabolism , Anticoagulants/pharmacology , Factor Xa Inhibitors , Nadroparin/pharmacology , Thrombin/antagonists & inhibitors , Thrombophlebitis/metabolism , Adult , Aged , Anticoagulants/administration & dosage , Anticoagulants/pharmacokinetics , Anticoagulants/therapeutic use , Creatinine/metabolism , Female , Humans , Injections, Subcutaneous , Kidney/physiopathology , Male , Metabolic Clearance Rate , Middle Aged , Nadroparin/administration & dosage , Nadroparin/pharmacokinetics , Nadroparin/therapeutic use , Thrombophlebitis/drug therapy
4.
Thromb Haemost ; 79(2): 338-41, 1998 Feb.
Article in English | MEDLINE | ID: mdl-9493587

ABSTRACT

Venous thromboembolism may be efficiently treated by once-a-day (o.d.) administration of a high dose of low molecular weight heparin (LMWH) instead of administration of the same total dose in two injections a day (b.i.d.). To reduce the volume of the subcutaneous (s.c.) injection, a more concentrated form of the drug is advisable. This study was designed to compare the bioavailability of 2 formulations of nadroparin containing 10,250 and 20,500 anti-Xa IU x ml(-1) respectively. This was an open, randomized, cross-over study where 12 healthy volunteers (age 18-35) were enrolled. They received either 90 anti-Xa IU x kg(-1) b.i.d. of the 10,250 IU preparation (treatment A), or 180 anti-Xa IU x kg(-1) o.d. of the 20,500 IU preparation (treatment B) for 10 days. On day 1, the subjects were sampled between 0 and 12 h (treatment A) or between 0 and 24 h (treatment B). On day 10, they were sampled between 0 and 12 h and between 12 and 24 h (treatment A) or between 0 and 24 h (treatment B). Anti-Xa and anti-IIa activities were determined by specific chromogenic assays. The main result of the study was that the bioavailability of the anti-Xa activity of the 2 nadroparin formulations was equivalent, as shown by the comparison of the AUC(0-12 h) plus AUC(12-24 h) (treatment A) and the AUC(0-24 h) (treatment B), calculated on day 10. This study also allowed a number of interesting observations to be made. 1) Between day 1 and day 10, there was an accumulation of the anti-Xa activity for treatment A but not for treatment B (accumulation factors: 1.6 and 1.1 respectively); 2) On day 10, the AUC(0-12 h) were slightly but significantly lower than the AUC(12-24 h) suggesting a circadian effect for anti-Xa and anti-IIa activities; 3) the clearance of the anti-Xa activity was comparable at the 2-dose regimens, while that of the anti-IIa activity was lower in treatment B than in treatment A, indicating a significant dose effect for the pharmacodynamics of the longer heparin chains; 4) On average, the clearance of the anti-IIa activity was twice as high as that of the anti-Xa activity; 5) For treatment B, significant APTT prolongations were noticed at Tmax (prolongation factor: 1.7 +/- 0.25), in relation with the anti-IIa activity (0.3 +/- 0.1 IU x ml(-1)).


Subject(s)
Anticoagulants/administration & dosage , Anticoagulants/pharmacokinetics , Factor Xa Inhibitors , Nadroparin/administration & dosage , Nadroparin/pharmacokinetics , Thrombophlebitis/drug therapy , Adolescent , Adult , Chemistry, Pharmaceutical , Cross-Over Studies , Heparin/administration & dosage , Humans , Injections, Subcutaneous
5.
J Clin Invest ; 94(1): 16-24, 1994 Jul.
Article in English | MEDLINE | ID: mdl-8040257

ABSTRACT

Myasthenia gravis (MG) is an autoimmune disease mediated by auto-antibodies that attack the nicotinic acetylcholine receptor (AChR). To elucidate the molecular mechanisms underlying the decrease in AChR levels at the neuromuscular junction, we investigated the regulation of AChR expression by analyzing mRNA of the two AChR alpha subunit isoforms (P3A+ and P3A-) in muscle samples from myasthenic patients relative to controls. We applied a quantitative method based on reverse transcription of total RNA followed by polymerase chain reaction (PCR), using an internal standard we constructed by site-directed mutagenesis. An increased expression of mRNA coding for the alpha subunit of the AChR isoforms was observed in severely affected patients (P < 0.003 versus controls) but not in moderately affected patients, independently of the anti-AChR antibody titer. Study of mRNA precursor levels indicates a higher expression in severely affected patients compared to controls, suggesting an enhanced rate of transcription of the message coding for the alpha subunit isoforms in these patients. We have also reported that mRNA encoding both isoforms are expressed at an approximate 1:1 ratio in controls and in patients. We have thus identified a new biological parameter correlated with disease severity, and provide evidence of a compensatory mechanism to balance the loss of AChR in human myasthenia gravis, which is probably triggered only above a certain degree of AChR loss.


Subject(s)
Muscles/chemistry , Myasthenia Gravis/metabolism , RNA, Messenger/analysis , Receptors, Cholinergic/genetics , Adolescent , Adult , Base Sequence , Biopsy , Child , Female , Humans , Male , Middle Aged , Molecular Sequence Data , Muscles/pathology , Polymerase Chain Reaction , RNA Precursors/analysis , Receptors, Cholinergic/analysis
6.
Arch Fr Pediatr ; 46(10): 733-6, 1989 Dec.
Article in French | MEDLINE | ID: mdl-2697195

ABSTRACT

We have retrospectively analysed the clinical and biological features as well as the outcome of 18 accelerated phases having occurred in 11 patients with the Chediak-Higashi syndrome. This complication is very frequent and is characterized by a multi-visceral lymphohistiocytic infiltration with hemophagocytosis leading to pancytopenia, a bleeding disorder secondary to low fibrinogen level, hypertriglyceridemia and hemodilution. The accelerated phase of the Chediak-Higashi syndrome is identical to the manifestations of familial erythrophagocytic lymphohistiocytosis and of the viral-associated hemophagocytic syndrome. The outcome was invariably fatal before the use of etoposide (VP 16) in association with steroids and intrathecal methotrexate. Complete remission with this management regimen was observed in 7/7 cases. However, remissions were only transient. HLA identical bone marrow transplantation appeared to be the only therapeutic strategy capable of curing the disease (3/3 patients). Non transplanted patients relapsed and died as well as one patient who received a HLA non identical bone marrow transplantation. Due to the frequency and the severity of the accelerated phase of the Chediak-Higashi syndrome, HLA identical bone marrow transplantation should be proposed as early as possible after the onset of the accelerated phase.


Subject(s)
Bone Marrow Transplantation , Chediak-Higashi Syndrome/etiology , Adrenal Cortex Hormones/therapeutic use , Chediak-Higashi Syndrome/blood , Chediak-Higashi Syndrome/therapy , Child , Child, Preschool , Drug Therapy, Combination , Etoposide/therapeutic use , Humans , Prednisone/therapeutic use
7.
Blood ; 74(1): 512-6, 1989 Jul.
Article in English | MEDLINE | ID: mdl-2665844

ABSTRACT

Three consecutive patients with the severe phenotype of leukocyte adhesion deficiency characterized by a defective expression of LFA-1, Mac-1 (CR3), and p150.95 on leukocytes have received HLA partially incompatible bone marrow transplantation (BMT). The degree of HLA incompatibility between related donors and recipients was 2 HLA antigens in one and one full haplotype in the two others. Graft-v-host disease (GVHD) prophylaxis consisted in T-cell depletion of the bone marrow inoculum and a 60-day course of cyclosporin A. A first attempt led to autologous recovery in one patient. The second transplant in this patient and the first transplant in the two others led to stable partial engraftment of lymphocytes and phagocytic cells, as shown by expression of adhesion molecules (LFA-1, Mac-1) on leukocytes and by HLA typing and restriction fragment-length polymorphism studies using minisatellite probes. Although the level of mixed chimerism was lower in one patient (7% to 30% donor cells) and greater than 50% in the two others, recovery of lymphocyte and phagocytic cell functions was sufficient enough to allow the patient to lead a normal life, infection free in the three cases. These patients, now 57, 32, and 19 months post-transplant, are in good condition without any therapy. These results lead us to propose that the LFA-1 molecule plays a role in HLA-incompatible graft rejection, probably by mediating adhesion of cytotoxic T and non-T lymphocytes to their targets.


Subject(s)
Bone Marrow Transplantation , Cell Adhesion , Hematologic Diseases/therapy , Leukocytes/physiology , Antibody Formation , Antigens, Differentiation/deficiency , Bone Marrow/immunology , Chimera , HLA Antigens/analysis , Humans , Integrin alphaXbeta2 , Killer Cells, Natural/physiology , Lymphocyte Function-Associated Antigen-1 , Macrophage-1 Antigen
8.
J Autoimmun ; 2(3): 241-58, 1989 Jun.
Article in English | MEDLINE | ID: mdl-2788427

ABSTRACT

Myasthenia Gravis (MG) is an autoimmune disorder of neuromuscular transmission associated with antibodies (Ab) against acetylcholine receptor (AChR). Autoantibody production is a T-cell-dependent phenomenon perhaps caused by aberrant immunoregulation. So far, a possible role for immunoregulatory molecules has not been investigated in the pathogenesis of MG. Since interleukin-2 (IL-2) is able to induce peripheral blood mononuclear cell (PBMC) proliferation without a previous activating signal and to upregulate IL-2-receptor expression, we have evaluated the activation state of PBMC in patients with MG, by cytofluorographic analysis of CD25 expression and by testing their sensitivity to recombinant IL-2 (rIL-2) without any known previous stimulation. We found no significant difference in CD25 expression in a large group of patients compared to controls. However, proliferative responses to rIL-2 were significantly higher in MG patients than in controls. In MG, as in controls, this response was time- and dose-dependent, was inhibited by an anti-IL-2 receptor Ab and correlated with an increased percentage of CD25+ T cells after rIL-2 exposure. The response was greater in patients with a high anti-AChR Ab titer and a severe form of the disease, and in patients tested before thymectomy. Thus blood T cells in MG showed functional signs of preactivation (high sensitivity to rIL-2 alone) without detectable CD25 expression on fresh cells, raising the possibility of aberrant IL-2 receptor regulation and/or expression in MG T cells. Decreased sensitivity to rIL-2 after thymectomy, associated with general clinical improvement, suggests a role for activated cells originating from the thymus in the pathogenesis of MG, and is of clinical relevance in patient follow-up. Our findings also provide a new approach in the study of MG pathogenesis: the search for aberrant immunoregulation mechanisms linked to defects in lymphokine circuits.


Subject(s)
Interleukin-2/pharmacology , Lymphocyte Activation , Myasthenia Gravis/immunology , Adult , Aged , Female , Humans , In Vitro Techniques , Male , Middle Aged , Myasthenia Gravis/surgery , Phenotype , Receptors, Interleukin-2 , T-Lymphocytes/immunology , Thymectomy
9.
Cancer Genet Cytogenet ; 38(2): 205-13, 1989 Apr.
Article in English | MEDLINE | ID: mdl-2655886

ABSTRACT

A subacute myelomonocytic leukemia was diagnosed in 28-month-old cotwins. At this age, their spontaneously dividing cells had a normal karyotype. A few months later, after treatment with 6-mercaptopurine, the following karyotypes were observed: 50,XX, +X, +13, +19, +21 in one and 51,XX, +X, +X, +10, +19, +21 in the other. After bone marrow transplantation, both relapsed although they had received high doses of chemo- and radiotherapy. One developed a clone 46,XX,del(20q), which acquired other clonal rearrangements. The other child developed two different abnormal clones, both with unbalanced rearrangement of chromosome 13. Some of these clones may correspond to immature erythroblasts. The gain of chromosomes, especially for #13, which occurred independently in the cotwins by various mechanisms and at different periods during the disease, is very striking. It may indicate the existence of a strong selective advantage for trisomic 13 cells and may be related to the genetic constitution of the patients.


Subject(s)
Diseases in Twins , Karyotyping , Leukemia, Myelomonocytic, Acute/genetics , Twins, Monozygotic , Twins , Bone Marrow Transplantation , Chromosome Aberrations , Chromosome Disorders , Chromosomes, Human, Pair 13 , Female , Humans , Infant , Leukemia, Myelomonocytic, Acute/radiotherapy , Leukemia, Myelomonocytic, Acute/therapy , Mercaptopurine/therapeutic use
12.
Presse Med ; 17(11): 528-32, 1988 Mar 26.
Article in French | MEDLINE | ID: mdl-2965360

ABSTRACT

HIV infection of the newborn is now known to result mostly from mother-to-foetus transmission. The risk of transmission is at least 40 p. 100. However, the circumstances of passage are little known, and there is no maternal virological parameter capable of evaluating individual risks. The disease is more severe in children than in adults. Rare are the children who remain asymptomatic for more than 15 months; one out of three of them develop severe acquired immunodeficiency syndrome and die within the first 2 or 3 years of life. A specific encephalopathy is observed in about 30 p. 100 of the infected children. Kaposi's sarcoma is exceptional. Since there is no contagion between children, those who are in fairly good clinical condition should have a family and school life as normal as possible.


Subject(s)
Acquired Immunodeficiency Syndrome/transmission , Infant, Newborn, Diseases/transmission , Acquired Immunodeficiency Syndrome/immunology , Acquired Immunodeficiency Syndrome/therapy , Female , Humans , Infant, Newborn , Infant, Newborn, Diseases/immunology , Infant, Newborn, Diseases/therapy , Maternal-Fetal Exchange , Pregnancy , Prognosis
13.
Immunol Res ; 7(3): 189-99, 1988.
Article in English | MEDLINE | ID: mdl-3264005

ABSTRACT

Several cellular aspects were investigated in a large series of patients with MG. First, non-Ag-specific proliferation was tested by measuring the response to r-IL2. Thymocytes from most MG patients showed hyperactivity to r-IL2. Peripheral blood lymphocytes (PBL) from some patients also showed a high response to r-IL2. These responding patients were generally those tested before thymectomy, presenting a high anti-AChR Ab titer and a severe form of the disease. Second, Ag-specific proliferation of MG PBL was assayed using 8 synthetic peptides corresponding to selected domains of torpedo or human AChR. Only 2 peptides gave a positive response in a significant number of patients, essentially in those presenting high anti-AChR Ab titer. The first is located near the alpha-bungarotoxin binding site and the second is in a cytoplasmic domain, according to models predicting the AChR transmembrane orientation. The positive results were essentially obtained with the human peptides; the corresponding torpedo peptides were positive in very few patients. Both human and torpedo peptides which include a part of the alpha-bungarotoxin binding site were negative. Finally, although morphological abnormalities were clearly visible in thymic hyperplasia, no correlation could be established between the thymus type and the cellular proliferation either to r-IL2, or to the peptides. Overall, our data indicate that cell-dependent mechanisms participate in the pathogenesis of MG, but the level of their involvement deserves further investigation.


Subject(s)
Immunity, Cellular , Myasthenia Gravis/immunology , Humans , Immunohistochemistry , Lymphocyte Activation , Myasthenia Gravis/pathology , Peptide Mapping , Receptors, Cholinergic/immunology , T-Lymphocytes/immunology , T-Lymphocytes/pathology , Thymus Hyperplasia/immunology , Thymus Hyperplasia/pathology
14.
Rev Mal Respir ; 5(2): 173-8, 1988.
Article in French | MEDLINE | ID: mdl-3293128

ABSTRACT

The authors report on a series of 255 thymomas and the associated diseases most often auto-immune, myasthenia is the disease most frequently encountered (61% of cases). Next, but with a much reduced frequency of around 2%, come other diseases such as hypogammaglobulinaemia, erythroblastopenic anaemia, and disseminated lupus erythematosis. The authors analyse the effect of ablating the thymoma on the associated disease; those with myasthenia are the principal beneficiaries of thymic ablation, 83% in this series experiencing a good response. Besides myasthenia only erythroblastopenic anaemia obtained some benefit from thymic ablation; in all the other cases surgery to the thymic tumour had no benefit on the associated disease. In the light of their own experience the authors made a review of the literature of the different diseases associated with thymomas and made the point of the efficacy of thymectomy in the different diseases.


Subject(s)
Thymoma/complications , Thymus Neoplasms/complications , Agammaglobulinemia/complications , Anemia, Aplastic/complications , Autoimmune Diseases/complications , Humans , Myasthenia Gravis/complications , Thymectomy , Thymoma/surgery , Thymus Neoplasms/surgery
16.
J Clin Immunol ; 4(2): 92-7, 1984 Mar.
Article in English | MEDLINE | ID: mdl-6609935

ABSTRACT

The in vivo effects of corticotherapy on thymocyte subpopulations have been evaluated in patients with myasthenia gravis (MG). Ten patients receiving high-dose, long-term treatment were studied and compared with two control groups (MG untreated patients and normal age-matched subjects). In the treated group, the thymus was generally involuted; the percentage of OKT6+ or OKT4+T8+ thymocytes was profoundly decreased compared to controls. A significant percentage of OKT10 - cells was detected particularly among older patients, suggesting steroid-induced immigration. Conversely the percentage of more mature OKT3+ cells was increased. The balance between OKT4+T8- and OKT4-T8+ cells was unchanged in young patients (less than 40 years old) and increased in the older group. These data show that, as in the mouse, corticosteroids profoundly alter human thymocyte subsets.


Subject(s)
Adrenal Cortex Hormones/pharmacology , Myasthenia Gravis/drug therapy , T-Lymphocytes/classification , Adolescent , Adult , Aging , Antibodies, Monoclonal , Female , Humans , Male , Middle Aged , Myasthenia Gravis/immunology , Prednisone/therapeutic use , T-Lymphocytes/drug effects
17.
Neurology ; 34(1): 66-71, 1984 Jan.
Article in English | MEDLINE | ID: mdl-6228745

ABSTRACT

The relationship between the titers of antibody against acetylcholine receptor (AChR) and T helper/suppressor balance (assessed by the OKT4/OKT8 ratio) were investigated in 74 patients with myasthenia gravis (MG). All patients with elevated AChR antibody titers (greater than 100 nM) had hyperplastic thymuses, while most patients with low or negative antibody titers (less than 1 nM) had involuted thymuses. All patients with thymoma had positive, though not very high, antibody titers. No correlation was found between anti-AChR antibody levels and OKT4/OKT8 ratios except for patients with thymoma. Thus, it appears that AChR antibody titers are more closely related to thymic pathology than to peripheral T cell imbalance. These results are consistent with the hypothesis giving a central role to thymic lymphocytes in the AChR antibody production, either as antibody producer B cells or helper T cells.


Subject(s)
Autoantibodies/immunology , Myasthenia Gravis/immunology , Receptors, Cholinergic/immunology , T-Lymphocytes/immunology , Acetylcholine/immunology , Adult , Female , Humans , Male , T-Lymphocytes, Helper-Inducer/immunology , T-Lymphocytes, Regulatory/immunology , Thymus Gland/immunology
18.
Clin Immunol Immunopathol ; 28(2): 272-81, 1983 Aug.
Article in English | MEDLINE | ID: mdl-6223767

ABSTRACT

Using monoclonal anti-T-cell antibodies, we have studied peripheral blood T-cell subsets in 53 patients with myasthenia gravis before and after thymectomy (Tx). Before Tx, the mean OKT4/OKT8 ratio was higher in patients than in controls. Furthermore patients showed a high number of cells reacting simultaneously with the OKT4 and OKT8 antibodies. Shortly after surgery, the helper/suppressor ratio was increased in most of the patients, and the doubly reactive subset decreased to normal levels. However, 6 to 12 months after Tx the OKT4/OKT8 ratio was significantly decreased, particularly in patients showing clinical improvement. The percentage of total T cells was slightly but significantly reduced. A group of 14 patients studied more than 2 years after Tx presented very low OKT4/OKT8 ratios. Thymectomy in MG appears to lead to a gradual decrease of the T-helper subset which could contribute to its favorable effect on the course of the disease.


Subject(s)
Myasthenia Gravis/immunology , T-Lymphocytes, Helper-Inducer/immunology , T-Lymphocytes, Regulatory/immunology , Thymectomy , Adult , Antibodies, Monoclonal/immunology , Female , Humans , Leukocyte Count , Long-Term Care , Male , Myasthenia Gravis/complications , Myasthenia Gravis/surgery , T-Lymphocytes, Cytotoxic/immunology , Thymoma/complications , Thymoma/surgery , Thymus Neoplasms/complications , Thymus Neoplasms/surgery
19.
Clin Exp Immunol ; 45(1): 1-8, 1981 Jul.
Article in English | MEDLINE | ID: mdl-6458432

ABSTRACT

Functional T cell subsets have been evaluated in the peripheral blood of patients with myasthenia gravis using monoclonal anti-T cell antibodies and a suppressor cell assay based on the suppression of the mixed-lymphocyte reaction by concanavalin A-activated lymphocytes. A significant decline of suppressor cells was found in a large proportion of patients, both by direct count using the anti-suppressor-cytotoxic T cell antibody (OKT8) and by the suppressor assay. Patients also showed an increase in immature T cells defined by their simultaneous reaction with the anti-helper cell (OKT4) and anti-suppressor cell (OKT8) antibody. Thymectomy tended to enhance the deficit in suppressor cells, and to induce the disappearance of double-labelled cells.


Subject(s)
Antilymphocyte Serum/immunology , Myasthenia Gravis/immunology , T-Lymphocytes/immunology , Adolescent , Adult , Aged , Antibodies, Monoclonal/immunology , Antibody Specificity , Cell Division , Concanavalin A/pharmacology , Female , Humans , Leukocyte Count , Lymphocyte Activation , Male , Middle Aged , Phytohemagglutinins/pharmacology , T-Lymphocytes, Regulatory/immunology , Thymectomy
20.
Sem Hop ; 56(37-38): 1502-5, 1980 Oct 15.
Article in French | MEDLINE | ID: mdl-6254170

ABSTRACT

Good results were obtained in 80 p. cent of 248 patients seen after more than 15 months following the operation. Results are grouped as a function of the different characteristic features of the patients and three groups can be defined: failures, improvement, remissions. These results contradict those who assert that thymectomy is of no value for severe cases. Cervicotomy is performed for non-tumoral forms or for small tumors; sternotomy is reserved for large median thymomas; anterolateral thoracotomy for laterally located thymomas and tracheotomized patients. Postoperative tracheotomy is very rarely needed. Patients are followed-up by clinical signs and ergodynamometric tracings. The prognosis for the myasthenia is not affected by the presence or absence of germinating centres in the non-tumoral thymus, or by the benign nature of the thymoma. Small undiagnosed tumors may be discovered during operation. Treatment of recurrences is difficult. The myasthenia may be associated with other auto-immune affections. The indication for operation in the purely ocular forms is debatable. Thymectomy may produce total remission even in severe cases, and may improve the results of medical treatment. Even in case of failure it can reduce the severity of the course of the disease.


Subject(s)
Myasthenia Gravis/therapy , Thymectomy , Adolescent , Adult , Aged , Child , Female , Follow-Up Studies , Humans , Male , Middle Aged , Neck/surgery , Prognosis , Sternum/surgery , Thymectomy/mortality , Thymoma/surgery , Thymus Neoplasms/surgery , Tracheotomy
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