Costimulation and Autoimmune Diabetes in BB Rats

Costimulatory signals regulate T-cell activation. To investigate the role of costimulation in autoimmunity and transplantation, we studied the BB rat model of type 1 diabetes. Diabetes-prone BB (BBDP) rats spontaneously develop disease when 55–120 days of age. We observed that two anti-CD28 monoclonal antibodies (mAb) with different functional activities completely prevented diabetes in BBDP rats. Anti-CD154 mAb delayed diabetes, whereas treatment with CTLA4-Ig or anti-CD80 mAb accelerated disease. Anti-CD86 or anti-CD134L mAbs had no effect. Diabetes resistant BB (BBDR) rats are disease-free, but >95% of them develop diabetes after treatment with polyinosinic-polycytidylic acid and an mAb that depletes Treg cells. In the induced BBDR model, anti-CD154 mAb delayed onset of diabetes, whereas CTLA4-Ig, anti-CD134L or either of the anti-CD28 mAbs had little or no effect. In contrast, blockade of the CD134-CD134L pathway was highly effective for preventing autoimmune recurrence against syngeneic islet grafts in diabetic BBDR hosts. Blockade of the CD40-CD154 pathway was also effective, but less so. These data suggest that the effectiveness of costimulation blockade in the treatment of type 1 diabetes is dependent on both the costimulatory pathway targeted and the mechanism of induction, stage, intensity and duration of the pathogenic process.     

Oral and subcutaneous sumatriptan in the acute treatment of migraine: an open randomized cress-over study

In an open, randomized cross-over study in 124 patients, we compared the efficacy, safety and patient preference of oral and subcutaneous sum triptan in the acute treatment of migraine. Patients were treated for 3 attacks or 3 months and then crossed over. Primary clinical efficacy was defined as a reduction in headache severity on a four-point self-rating scale from severe (3) or moderate (2) to mild (1) or none (0), or mild (1) to none (0). Efficacy was evaluated 2 h after the administration of subcutaneous and 4h after the administration of oral sumatriptan. Subcutaneous sumatriptan was significantly more effective than oral sumatriptan in relieving headache (over all three attacks 78% vs 61% improvement), improving clinical disability (55% vs 41 % improvement) and relieving nausea (69% vs 53%), vomiting (72% vs 32%) and phono- or photophobia (67% vs 49%). Median time to recurrence was shorter after subcutaneous (12.5 h) than after oral sumatriptan (18 h); the number of patients experiencing a recurrence was similar Patients reported more adverse events after subcutaneous sumatriptan (1.32 per attack) than after the oral form (0.85 per attack), but all adverse events were mild to moderate in intensity and of short duration. Patient opinion was more often positive after subcutaneous sumatriptan. These results may be useful in counselling patients to choose between the available marketed formulations of sumatriptan.     

超细β-磷酸三钙/聚-L-乳酸复合材料的制备与骨折内固定器的加工

目的：制备分散性良好的超细β-磷酸三钙(β-TCP)／聚-L-乳酸(PLLA)复合材料及新型可吸收骨折内固定器。方法：通过研磨方法制备β-TCP超细粒子，用一缩二乙二醇作分散剂研磨β-TCP后，再将β-TCP与PLLA超声混合，制得复合材料，经注塑加工制成可吸收骨钉，并采用扫描电镜等方法进行表征。结果与结论：用一缩二乙二醇作分散剂研磨β-TCP后再经超声混合，可以使β-TCP超细粒子在复合材料中分散均匀，粒子大小仅为300nm左右，β-TCP与PLlA基体之间结合良好。超细β-TCP／PLLA复合材料可加工成可吸收骨钉，弯曲强度达到100MPa左右，完全满足松质骨内固定的要求。     

Accelerating effects of epidermal growth factor on skin lesions of pemphigus vulgaris: a double-blind, randomized, controlled trial

BACKGROUND: Pemphigus vulgaris (PV) is a severe blistering disease involving the skin and mucous membranes. The most common causes of death in these patients are adverse effects of drugs, and infection. Skin lesions are one of the important sources of infection. Thus, any local treatment that could reduce healing time of lesions and consequently reduce the total dosage of drugs needed to treat is favourable. OBJECTIVE: To evaluate the efficacy of epidermal growth factor (EGF) in reducing healing time of lesions in patients with pemphigus vulgaris. METHODS: In this randomized, double-blind, within-patient, left/right, controlled trial, 20 hospitalized patients with pathologial and immunohistologial (direct and indirect immunoflourecence) proven pemphigus vulgaris (PV) were chosen. In addition, all patients had at least one appropriate pemphigus lesion on each side of the body that had not healed after 2-week systemic therapy and sterile saline washing. EGF (10 microg/g) in 0.1% silver sulfadiazine cream vs. 0.1% silver sulfadiazine cream alone was applied randomly on one side of the body. RESULTS: Kaplan-Meier survival analysis suggested that median time to heal with application of EGF plus silver sulfadiazine cream was 9 days, in comparison with 15 days for silver sulfadiazine cream alone (log-rank test, P=0.0003). No intervention-related adverse effect was observed during the study. CONCLUSIONS: EGF can significantly reduce healing time of skin lesions in patients with pemphigus vulgaris, at least when this cream base is applied (Cochrane skin group identifier: CSG20).     

Linkage of the MHC to familial multiple sclerosis suggests genetic heterogeneity. The Multiple Sclerosis Genetics Group

Multiple sclerosis (MS) is a demyelinating autoimmune disease of the central nervous system. While its etiology is not well understood, genetic factors are clearly involved. Until recently, most genetic studies in MS have been association studies using the case-control design testing specific candidate genes and studying only sporadic cases. The only consistently replicated finding has been an association with the HLA-DR2 allele within the major histocompatibility complex (MHC) on chromosome 6. Using the genetic linkage design, however, evidence for and against linkage of the MHC to MS has been found, fostering suggestions that sporadic and familial MS have different etiologies. Most recently, two of four genomic screens demonstrated linkage to the MHC, although specific allelic associations were not tested. Here, a dataset of 98 multiplex families was studied to test for an association to the HLA-DR2 allele in familial MS and to determine if genetic linkage to the MHC was due solely to such an association. Three highly polymorphic markers (HLA-DR, D6S273 and TNFbeta) in the MHC demonstrated strong genetic linkage (parametric lod scores of 4.60, 2.20 and 1.24, respectively) and a specific association with the HLA-DR2 allele was confirmed (TDT; P < 0.001). Stratifying the results by HLA-DR2 status showed that the linkage results were limited to families segregating HLA-DR2 alleles. These results demonstrate that genetic linkage to the MHC can be explained by the HLA-DR2 allelic association. They also indicate that sporadic and familial MS share a common genetic susceptibility. In addition, preliminary calculations suggest that the MHC explains between 17 and 62% of the genetic etiology of MS. This heterogeneity is also supported by the minority of families showing no linkage or association with loci within the MHC.      

Androgen receptor YAC transgenic mice carrying CAG 45 alleles show trinucleotide repeat instability

X-linked spinal and bulbar muscular atrophy (SBMA) is caused by a CAG repeat expansion in the first exon of the androgen receptor (AR) gene. Disease-associated alleles (37-66 CAGs) change in length when transmitted from parents to offspring, with a significantly greater tendency to shift size when inherited paternally. As transgenic mice carrying human AR cDNAs with 45 and 66 CAG repeats do not display repeat instability, we attempted to model trinucleotide repeat instability by generating transgenic mice with yeast artificial chromosomes (YACs) carrying AR CAG repeat expansions in their genomic context. Studies of independent lines of AR YAC transgenic mice with CAG 45 alleles reveal intergenerational instability at an overall rate of approximately 10%. We also find that the 45 CAG repeat tracts are significantly more unstable with maternal transmission and as the transmitting mother ages. Of all the CAG/CTG repeat transgenic mice produced to date the AR YAC CAG 45 mice are unstable with the smallest trinucleotide repeat mutations, suggesting that the length threshold for repeat instability in the mouse may be lowered by including the appropriate flanking human DNA sequences. By sequence-tagged site content analysis and long range mapping we determined that one unstable transgenic line has integrated an approximately 70 kb segment of the AR locus due to fragmentation of the AR YAC. Identification of the cis - acting elements that permit CAG tract instability and the trans -acting factors that modulate repeat instability in the AR YAC CAG 45 mice may provide insights into the molecular basis of trinucleotide repeat instability in humans.      

The presence of immunosuppressive ''p15E-like'' factors in the serum and urine of patients suffering from malign and benign breast tumours.

Autoantibodies in sera from patients with systemic lupus erythematosus (SLE) and onchocerciasis recognize calreticulin (CaR), a calcium-binding protein, as antigen. In this study we present the immunological properties of two synthetic peptides prepared to correspond to the 1-24 and 7-24 amino acid sequence of CaR. In contrast to information previously reported for the recombinant protein, the CaR-peptide analogues appeared immunoreactive to anti-Ro/SSA autoimmune sera. Human sera from patients with SLE, Sjögren's syndrome (SS), rheumatoid arthritis (RA), as well as mixed connective tissue disease (MCTD), demonstrated a positive autoimmune response (binding of antibodies), to the CaR-peptide analogues. These findings suggest that anti-calreticulin autoantibodies are not restricted to any disease specificity.     

Secretion of vascular endothelial growth factor/vascular permeability factor from human luteinized granulosa cells is human chorionic gonadotrophin dependent

Vascularization is a prominent event during corpus luteum formation, providing low density lipoproteins for steroid biosynthesis and enabling transport of secreted steroids. The process of vascularization is controlled by specific regulators. Vascular endothelial growth factor (VEGF), otherwise named vascular permeability factor (VPF), induces endothelial cell proliferation as well as angiogenesis in vivo and increases capillary permeability. Here we report the expression of VEGF/VPF mRNA by cultured human luteinized granulosa cells (GC) for at least 10 days. Without HCG VEGF/VPF expression declined after day 4 and by day 10 was reduced to approximately 30% of the value at day 4. However, after culture in the presence of 1 U/ml human chorionic gonadotrophin (HCG), expression of VEGF/VPF mRNA by GC was four times greater than control experiments by day 10, and increased 100% from day 4 to day 10. Simultaneously, HCG supplementation increased VEGF/VPF secretion by GC. Medium VEGF/VPF on day 3 was 13 pM without and 11 pM with HCG. Medium VEGF/VPF on day 10 was 6 pM without HCG and 29 pM with HCG. These results suggest that vascularization of the corpus luteum is induced by HCG-mediated effects of VEGF/VPF.      

Parameters of T cell mediated immunity to commensal micro-organisms in patients with chronic purulent rhinosinusitis: a comparison between delayed type hypersensitivity skin test, lymphocyte transformation test and macrophage migration inhibition factor assay.

In 75 patients with unexplained chronic purulent rhinosinusitis T cell mediated immunity to three micro-organisms frequently colonizing the human upper respiratory tract, viz. Haemophilus influenzae, streptococci and Candida albicans, was assessed. Delayed type hypersensitivity (DTH) skin test reactivity was measured in vivo, whereas the blastogenic responsiveness (lymphocyte transformation test; LTT) and lymphokine production (e.g. migration inhibition factor; MIF) of the lymphocytes upon antigen stimulation were measured in vitro. MIF was assayed with a recently developed test system using the human monocytoid cell-line U937 as indicator cells in agarose microdroplets. Two-thirds of the 75 patients tested showed a defective DTH response to one or more of the microbial antigens; this contrasted to the findings in 25 healthy subjects, of whom over 90% showed a positive DTH reaction to any of the three antigens. PHA skin tests were entirely normal in both patients and healthy controls. Microbial antigen-specific LTT responses fluctuated considerably in time from strongly positive to negative and vice versa in healthy individuals as well as in patients. In general however, blastogenic responses in patients were comparable to or even higher than those of healthy persons. In the MIF assay, lymphocytes of all healthy individuals tested showed production of MIF upon stimulation with all three antigens; this again contrasted to two-thirds of the patients, whose lymphocytes showed a defective MIF production. Fluctuations of MIF-production in time could not be established and a very good correlation existed between the data obtained in the MIF assay and those of the DTH skin tests. These results indicate that apart from skin testing, the MIF assay seems to be the most suitable parameter to assess defects in T cell reactivity towards microbial antigens. These defects exist in two-thirds of our patients suffering from chronic purulent rhinosinusitis.