Comparative sequencing of human and chimpanzee MHC class I regions unveils insertions/deletions as the major path to genomic divergence

Despite their high degree of genomic similarity, reminiscent of their relatively recent separation from each other ( approximately 6 million years ago), the molecular basis of traits unique to humans vs. their closest relative, the chimpanzee, is largely unknown. This report describes a large-scale single-contig comparison between human and chimpanzee genomes via the sequence analysis of almost one-half of the immunologically critical MHC. This 1,750,601-bp stretch of DNA, which encompasses the entire class I along with the telomeric part of the MHC class III regions, corresponds to an orthologous 1,870,955 bp of the human HLA region. Sequence analysis confirms the existence of a high degree of sequence similarity between the two species. However, and importantly, this 98.6% sequence identity drops to only 86.7% taking into account the multiple insertions/deletions (indels) dispersed throughout the region. This is functionally exemplified by a large deletion of 95 kb between the virtual locations of human MICA and MICB genes, which results in a single hybrid chimpanzee MIC gene, in a segment of the MHC genetically linked to species-specific handling of several viral infections (HIV/SIV, hepatitis B and C) as well as susceptibility to various autoimmune diseases. Finally, if generalized, these data suggest that evolution may have used the mechanistically more drastic indels instead of the more subtle single-nucleotide substitutions for shaping the recently emerged primate species.     

Identification of an Anti–Integrin αvβ6 Autoantibody in Patients With Ulcerative Colitis

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A case of planned pregnancy with an interruption in infliximab administration in a 27-year-old female patient with rheumatoid-factor-positive polyarthritis juvenile idiopathic arthritis which improved after restarting infliximab and methotrexate

We report a 27-year-old case of juvenile idiopathic arthritis (JIA) having been stopped infliximab during pregnancy. She was safely treated by infliximab therapy with premedications for preventing infusin reactions after her delivery, and then improved in the same manner as when she had been treated with infliximab therapy before pregnancy. As a result, it remains unclear whether or not we can use infliximab to control disease activities during pregnancy. In addition, it is also important to clarify whether or not premedications should be used when resuming infliximab treatment in such patients after pregnancy. These problems still remain controversial. More definitive data are needed in order to allow rheumatologists to better select the optimal TNF-alpha inhibitor therapy when treating pregnant JIA patients.     

Taeniasis and cysticercosis in Asia and the Pacific: present state of knowledge and perspectives

Several topics on taeniasis and cysticercosis in Asia and the Pacific are overviewed. In Asia and the Pacific, three human taeniid species have been recognized: Taenia solium, Taenia saginata and Taenia asiatica. The first topic is on evolution of T. solium. Mitochondrial DNA polymorphisms of T. solium worldwide are discussed with emphasis of two specific genotypes: American-African and Asian. The second topic is recent major advances in sero- and molecular-diagnosis of T. solium cysticercosis in humans, pigs and dogs. The third is the present situation of T. solium taeniasis/cysticercosis in Papua (Irian Jaya), Indonesia. The forth is the present situation of T. solium cysticercosis and T. saginata taeniasis in Bali, Indonesia. The fifth is the present situation of T. asiatica taeniasis in Asia and the Pacific and in North Sumatra, Indonesia. The sixth is on the debate of the exact definition of T. asiatica. Because T. asiatica can not be differentiated from T. saginata morphologically, it is time to re-evaluate T. saginata in Asia and the Pacific. New and broad-based surveys across this region are necessary from epidemiological and public health perspectives, based on evidence.     

Dermatomyositis as a complication of interferon-α therapy: a case report and review of the literature

Autoimmune disorder is one of the important side effects of interferon-α therapy. Some polymyositis cases as complication of interferon-α therapy were reported, but dermatomyositis were rarely. We report a case of dermatomyositis as a complication of interferon-α therapy for hepatitis C. A 52-year-old Japanese man was treated by combination therapy with pegylated interferon-α-2b and ribavirin for hepatitis C. Three months after the initiation of therapy, he showed erythema in the posterior cervical to dorsal and anterior cervical to thoracic regions, weight loss, general malaise, muscle pain, and severe increase in levels of muscle enzymes. We made a diagnosis of dermatomyositis according to these clinical features, proximal muscle-predominant myogenic change on electromyography, and infiltration of monocytes and CD4+-dominant lymphocytes on skin biopsy, although myositis-associated antibodies were absent. He was successfully treated with intravenous immunoglobulin and tacrolimus in addition to glucocorticoid. This is a very rare case of dermatomyositis associated with interferon-α therapy. We reviewed several similar published cases and the association of dermatomyositis and type I interferon.     

Favorable outcomes of tacrolimus compared with cyclosporine A for GVHD prophylaxis in HSCT for standard-risk hematological diseases

Although calcineurin inhibitors (CNIs) with short-term methotrexate (stMTX) constitute standard prophylaxis for graft-versus-host diseases (GVHD) in hematopoietic stem cell transplantations (HSCT), comparative efficacy of cyclosporine A (CsA) and tacrolimus (Tac) still remains unclear. We have altered GVHD prophylaxis for standard-risk hematological malignancies from CsA (target trough level, 500 ng/mL) to Tac (15 ng/mL) both with stMTX in May 2008, enabling us to compare the efficacy of CNIs with little selection biases. The cumulative incidence of acute and chronic GVHD was comparable for CsA and Tac. Among the GVHD low-risk patients who received stem cells from matched sibling donors or cord blood, the Tac arm had a trend for favorable control of grade III–IV acute GVHD (6.7 vs. 30.0 %, p?=?0.2), which may contribute to the significantly better overall survival (p?=?0.048) and relapse-free survival (p?=?0.043) in that group. Inadequate concentration of CNIs in early phase of HSCT affected the cumulative incidence of acute GVHD in the CsA but not in the Tac arm. There were no differences in the GVHD incidence and survival outcomes between CsA and Tac in the GVHD high-risk subgroup. This study underlies the significance of maintaining adequate CsA concentration in standard-risk HSCT.