Immune responses against SARS-coronavirus nucleocapsid protein induced by DNA vaccine

The nucleocapsid （N） protein of SARS-coronavirus （SARS-CoV） is the key protein for the formation of the helical nucleocapsid during virion assembly. This protein is believed to be more conserved than other proteins of the virus, such as spike and membrane glycoprotein. In this study, the N protein of SARS-CoV was expressed in Escherichia coli DHSalpha and identified with pooled sera from patients in the convalescence phase of SARS. A plasmid pCI-N, encoding the full-length N gene of SARS-CoV, was constructed. Expression of the N protein was observed in COS1 cells following transfection with pCI-N. The immune responses induced by intramuscular immunization with pCI-N were evaluated in a murine model. Serum anti-N immunoglobutins and splenocytes proliferative responses against N protein were observed in immunized BALB/c mice. The major immunoglobulin G subclass recognizing N protein was immunoglobulin G2a, and stimulated splenocytes secreted high levels of gamma interferon and IL-2 in response to N protein. More importantly, the immunized mice produced strong delayed-type hypersensitivity （DTH） and CD^8＋ CTL responses to N protein.     

The epidemiology of hyperuricaemia and gout in Taiwan aborigines

To determine the prevalence of hyperuricaemia, gout and gout-related factors in Central Taiwan Atayal aborigines, 342 subjects over 18 yr old were interviewed and examined. A questionnaire was designed to screen for signs and symptoms of gout and gout-related risk factors. Serum uric acid, triglyceride and creatinine were measured in all subjects. The prevalence of hyperuricaemia was 41.4% and that of gout 11.7% in aborigines. The uric acid level was 7.9+/-1.7 mg/dl in males and 5.7+/-1.5 in females, and differed significantly under age 70 yr (P < 0.001). Significantly increased triglyceride, creatinine and alcoholism was found in gouty patients compared with non-gouty patients. In 40 cases with gout, 54% had tophi and 35% of their first- degree relatives had gout. The high prevalence of hyperuricaemia and gout in Taiwan Atayal aborigines, a significant family predisposition, increased creatinine level and alcoholism suggest multiple factors affecting the hyperuricaemia.      

Intestinal pseudo-obstruction as an initial presentation of systemic sclerosis in two children

Two children are reported in whom intestinal pseudo-obstruction was the initial manifestation of systemic sclerosis. Gastrointestinal symptoms and skin changes resolved or improved in both children following treatment with prednisone and penicillamine (case 1) or methotrexate (case 2), although radiological changes of the gastrointestinal tract persisted at 3 and 2 yr of follow-up, respectively.      

Interleukin-10 promoter polymorphisms in rheumatoid arthritis and Felty's syndrome

OBJECTIVE: To examine whether promoter polymorphisms associated with variation in interleukin-10 (IL-10) production are relevant to the development of rheumatoid arthritis (RA) or Felty's syndrome (FS). METHODS: DNA was obtained from 44 FS patients, 117 RA patients and 295 controls. The promoter region between -533 and - 1120 was amplified by polymerase chain reaction, and polymorphisms detected by restriction enzyme digest or sequence-specific oligonucleotide probing. RESULTS: We found no significant difference in allele or haplotype frequencies between the groups. CONCLUSION: There is no association between FS or RA and these recently identified IL-10 promoter polymorphisms. Other genetic or environmental factors could explain the alterations in IL-10 levels seen in these conditions.      

Ultra‐deep T cell receptor sequencing reveals the complexity and intratumour heterogeneity of T cell clones in renal cell carcinomas

The recognition of cancer cells by T cells can impact upon prognosis and be exploited for immunotherapeutic approaches. This recognition depends on the specific interaction between antigens displayed on the surface of cancer cells and the T cell receptor (TCR), which is generated by somatic rearrangements of TCR α‐ and β‐chains (TCRb). Our aim was to assess whether ultra‐deep sequencing of the rearranged TCRb in DNA extracted from unfractionated clear cell renal cell carcinoma (ccRCC) samples can provide insights into the clonality and heterogeneity of intratumoural T cells in ccRCCs, a tumour type that can display extensive genetic intratumour heterogeneity (ITH). For this purpose, DNA was extracted from two to four tumour regions from each of four primary ccRCCs and was analysed by ultra‐deep TCR sequencing. In parallel, tumour infiltration by CD4, CD8 and Foxp3 regulatory T cells was evaluated by immunohistochemistry and correlated with TCR‐sequencing data. A polyclonal T cell repertoire with 367–16 289 (median 2394) unique TCRb sequences was identified per tumour region. The frequencies of the 100 most abundant T cell clones/tumour were poorly correlated between most regions (Pearson correlation coefficient, –0.218 to 0.465). 3–93% of these T cell clones were not detectable across all regions. Thus, the clonal composition of T cell populations can be heterogeneous across different regions of the same ccRCC. T cell ITH was higher in tumours pretreated with an mTOR inhibitor, which could suggest that therapy can influence adaptive tumour immunity. These data show that ultra‐deep TCR‐sequencing technology can be applied directly to DNA extracted from unfractionated tumour samples, allowing novel insights into the clonality of T cell populations in cancers. These were polyclonal and displayed ITH in ccRCC. TCRb sequencing may shed light on mechanisms of cancer immunity and the efficacy of immunotherapy approaches. Copyright © 2013 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.     

Activated protein C resistance: molecular mechanisms based on studies using purified Gln506-factor V

Gln506-factor V (FV) was purified from plasma of an individual homozygous for an Arg506Gln mutation in FV that is associated with activated protein C (APC) resistance. Purified Gln506-FV, as well as Gln506-FVa generated by either thrombin or FXa, conveyed APC resistance to FV-deficient plasma in coagulation assays. Clotting assay studies also suggested that APC resistance does not involve any abnormality in FV-APC-cofactor activity. In purified reaction mixtures, Gln506-FVa in comparison to normal FVa showed reduced susceptibility to APC, because it was inactivated approximately 10-fold slower than normal Arg506-FVa. It was previously reported that inactivation of normal FVa by APC involves an initial cleavage at Arg506 followed by phospholipid- dependent cleavage at Arg306. Immunoblot and amino acid sequence analyses showed that the 102-kD heavy chain of Gln506-FVa was cleaved at Arg306 during inactivation by APC in a phospholipid-dependent reaction. This reduced but measurable susceptibility of Gln506-FVa to APC inactivation may help explain why APC resistance is a mild risk factor for thrombosis because APC can inactivate both normal FVa and variant Gln506-FVa. In summary, this study shows that purified Gln506- FV can account for APC resistance of plasma because Gln506-FVa, whether generated by thrombin or FXa, is relatively resistant to APC.