Mitsuru Nakajima

Polymorphisms of HLA class II genes and autoimmune responses to Ro/SS-A-La/SS-B among Japanese subjects

OBJECTIVE To investigate HLA class II allele associations with autoantibody responses to Ro/SS-A and La/SS-B among Japanese subjects. METHODS Haplotype and allele distributions, along with molecular polymorphisms, of HLA class II genes were analyzed by polymerase chain reaction-restriction fragment length polymorphism in 41 Japanese women with precipitating autoantibodies to Ro/SS-A and/or La/SS-B. RESULTS Among women with both Ro/SS-A and La/SS-B antibodies, the HLA class II haplotype DRB1*08032/DQA1*0103/DQB1*0601 and DRB1*08032 allele showed significantly increased frequencies compared with patients with anti-Ro/SS-A alone or with normal controls. All women with both anti-Ro/SS-A and anti-La/SS-B, but not those with anti-Ro/SS-A alone, carried DRB1 alleles that shared the same amino acid residues at positions 14-31 and 71 of the hypervariable regions of the DRB1 chain. All anti-Ro/SS-A positive women carried 1 or 2 alleles of DQB1*06 and DQB1*03 subtypes that shared the same amino acid residues at positions 71-77 of the DQB1 chain. HLA class II allele distributions did not differ among 3 anti-Ro/SS-A positive groups with different disease expressions, i.e., patients with systemic lupus erythematosus, patients with primary Sjögrens syndrome, and women with no apparent symptoms of rheumatic disease. CONCLUSION HLA class II allele distributions differ among anti-Ro/SS-A positive subjects according to the presence or absence of coexisting anti-La/SS-B antibodies, but not according to disease expression. Our findings suggest that different HLA class II molecules might control the development of anti-Ro/SS-A and/or anti-La/SS-B antibodies in the autoimmune response to the Ro/SS-A-La/SS-B complex.

Cytochemical localization of blood group substances in human salivary glands using lectin-gold complexes

We investigated localization of blood group antigens and their related substances in human labial salivary and submandibular glands by application of a post-embedding cytochemical staining procedure using lectin- or glycoprotein-gold complexes. Surgical tissue was obtained from 10 patients. Blood group-specific lectins, such as Dolichos biflorus agglutinin or Helix pomatia agglutinin (group A-specific), Griffonia simplicifolia agglutinin-I B4 (group B-specific), and Ulex europaeus agglutinin I (group H-specific) could recognize A, B, and H antigens, respectively, only in mature secretory granules (mature SG), which were found preferentially in cells in the late phase of the maturation cycle. In immature secretory granules (immature SG), which were found in cells in the early or middle phase of the maturation cycle, no binding with these lectins was observed. The Golgi complexes and endoplasmic reticula also were not labeled with these lectins. In blood group O and B secretors, blood group antigens were uniformly distributed throughout all the mature SG examined. However, in blood group A secretors, the distribution was heterogeneous, i.e., in some granules only H antigen was demonstrated, whereas in others both A antigens and a small amount of H antigens were detected. Among the blood group-nonspecific lectins, wheat germ agglutinin (WGA) was found to bind more preferentially to immature SG than to mature SG. This was demonstrated irrespective of the blood group and secretor status of the tissue donor, except that in blood group A secretors WGA bound strongly to some mature SG which possessed A antigen. We discuss the significance of cellular and subcellular mosaic distribution of blood group antigens in connection with morphological differences of secretory granules and the maturation cycle of mucous cells.

Up-regulation of interleukin-2 mRNA in children with idiopathic nephrotic syndrome

The current hypothesis for the pathogenesis of childhood idiopathic nephrotic syndrome (INS) favors the involvement of a T cell-mediated immune response. Various cytokines derived from T cells may play a critical role in INS. Previous studies have measured serum or urine cytokine levels and suggest an imbalance of the T cell-mediated immune response. To elucidate the true profile of T cell-derived cytokines, we determined interleukin (IL)-2, interferon (IFN)-γ, IL-4, IL-10, and tumor necrosis factor (TNF)-α mRNA expression in children with INS. We collected mRNA from peripheral blood mononuclear cells together with plasma and urine from nine children in the acute and remission phases of INS. Expression of IL-2, IFN-γ, IL-4, IL-10, and TNF-α mRNA was determined by a quantitative real-time PCR assay. Plasma and urine cytokine concentrations were measured using a specific enzyme-linked immunosorbent assay. These data were compared between the acute and remission phase in the same patients. The IL-2 mRNA levels were significantly higher in the acute phase than in the remission phase, whilst no significant difference was found in the other cytokines investigated. There was no significant difference in the plasma and urine cytokine concentrations between the acute and remission phase. Our results indicate increased expression of IL-2 mRNA in the acute phase of INS, suggesting that IL-2, at least in part, might be involved in the pathophysiology of childhood INS.

Does skeletonization compromise the integrity of internal thoracic artery grafts

BACKGROUND There are few reports that demonstrate the chronologic changes in the functional integrity of the internal thoracic artery (ITA) wall after skeletonization. We investigated the impact of skeletonization on ITA wall integrity by immunohistochemical analyses in acute and chronic phases. METHODS Nine mongrel dogs underwent bilateral ITA dissection with one skeletonized vessel and the other pedicled. The following studies were performed 1 week (acute phase, n = 3) and 12 weeks (chronic phase, n = 6) after ITA harvesting. All specimens of the ITAs were stained by antibodies against von Willebrand Factor (VWF), endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS), and proliferating cell nuclear antigen (PCNA). After observation with confocal laser scanning microscopy, quantitative analyses of the staining signal for VWF and eNOS expressed on endothelial cells were performed. RESULTS There were significantly more microvessels positive for VWF in the adventitia of skeletonized ITAs than in the adventitia of pedicled ITAs but the expression of PCNA in both groups was minimal, as in normal vessels. iNOS was not detected in any specimen. The intensity of VWF and eNOS expressed by endothelial cells had no significant differences between groups at either phase. CONCLUSIONS The functional integrity of skeletonized ITA was similar to that of pedicled ITA in both acute and chronic phases. Although skeletonization induced neovascularization in the adventitia it did not induce proliferation of smooth muscle cells in the media, which is supposed to be a feature of vascular remodeling.

Histochemical Reactivity of Soybean Agglutinin with Blood Group Antigens and Their Precursor Substances in Acinar Cells of Human Pancreas

In human pancreas, soybean agglutinin (SBA) conjugated to horseradish peroxidase reacted with the acinar cells secreting blood group A and/or H antigen, but not with those secreting only B antigen. For detailed histochemical characterization of SBA staining, the effects of treatment with unlabeled lectins and of digestion of certain enzymes on SBA staining were investigated in formalin-fixed, paraffin-embedded pancreatic tissue from individuals of different blood groups. Pre-incubation of sections with unlabeled Dolichos biflorus agglutinin to block A antigen eliminated subsequent SBA staining in the cells secreting A antigen, although failing to induce any effects in those secreting H antigen. In contrast, pre-incubation with unlabeled Ulex europaeus agglutinin-I (UEA-I) to block H antigen abolished SBA staining in cells secreting H antigen but not in those secreting A antigen. Treatment with galactose oxidase yielded the same results as those with unlabeled UEA-I, i.e., SBA reactivity was significantly diminished in cells secreting H antigen but not in those secreting A antigen. Digestion with beta-galactosidase resulted in a slight decrease of SBA staining in the cells secreting H antigen. Accompanying the decrease of SBA staining, reactivity with Griffonia simplicifolia agglutinin-II (GSA-II) appeared for the first time in the enzyme-susceptible, SBA-reactive cells secreting H antigen. Pre-treatment with galactose oxidase abolished this effect of beta-galactosidase. The GSA-II reactivity disclosed by treatment with galactosidase was completely eliminated by digestion with beta-N-acetylhexosaminidase, indicating that GSA-II staining after digestion with galactosidase is due to exposed penultimate beta-N-acetyl-D-glucosamine residues. These results demonstrate that at least two substances react with SBA in acinar cells of human pancreas, one being terminal beta-N-acetyl-D-galactosamine residues of A antigen, and the other being terminal beta-D-galactose-(1----3 or 1----4)-beta-N-acetyl-D-glucosamine dimers in the precursor of blood group H antigen. Such dimers may exist in close proximity to L-fucose residues of H antigen, since unlabeled UEA-I blocked SBA staining.

Effects of alpha-L-fucosidase digestion on lectin staining in human pancreas.

We examined the effects of alpha-L-fucosidase digestion on lectin staining in formalin-fixed, paraffin-embedded human pancreatic tissue from individuals of different blood groups. Digestion with the enzyme resulted in apparent diminished intensity of Ulex europaeus agglutinin-I (UEA-I) staining in the acinar cells. In addition to the decreased intensity of UEA-I staining, reactivity with soybean agglutinin (SBA) was increased in the enzyme-susceptible, UEA-I-reactive cells. The intensity of Griffonia simplicifolia agglutinin-II (GSA-II) staining performed after beta-galactosidase digestion in UEA-I-reactive acinar cells was markedly increased by prior treatment with fucosidase. GSA-II staining following sequential digestion with fucosidase and galactosidase was completely abolished by subsequent digestion with beta-N-acetylhexosaminidase. These results therefore substantiate the previous assumption that SBA-reactive D-galactose-(beta 1-3,4)-N-acetyl-D-glucosamine and GSA-II reactive beta-N-acetyl-D-glucosamine imparted following galactosidase digestion represent precursors of H antigen. The present study further demonstrated that intense peanut agglutinin (PNA) staining was imparted after digestion with fucosidase in UEA-I-reactive sites in secretors. In contrast, nonsecretors showed vivid PNA staining that was usually detected throughout the pancreas without prior enzyme digestion. Here, fucosidase digestion had if any little effect on PNA staining. These results suggest that in secretors a terminal trisaccharide, fucosylated D-galactose-(beta 1-3)-N-acetyl-D-galactosamine exhibiting positive PNA reaction after fucosidase digestion, exists in UEA-I-reactive acinar cells. It is assumed that the secretor gene could control the step of final fucosylation of D-galactose-(beta 1-3)-N-acetyl-D-galactosamine in human pancreas.

A 4-year-old girl with autosomal dominant polycystic kidney disease complicated by a ruptured intracranial aneurysm

In patients with autosomal dominant polycystic kidney disease (ADPKD), intracranial aneurysms (ICAs) are extrarenal manifestations and may result in serious and potentially fatal outcome following rupture. Although ICAs are a well-known complication of ADPKD, nearly all cases of ICA occurring in the context of ADPKD are adults. Here, we report the case of a Japanese girl with ADPKD who developed a subarachnoid haemorrhage (SAH) due to a ruptured ICA at the age of 4 years. Conclusion:This report is intended to raise awareness that the use of noninvasive screening techniques such as three-dimensional CT angiography or magnetic resonance angiography to detect intracranial aneurysms should also be performed in paediatric patients with autosomal dominant polycystic kidney disease.

Ecthyma gangrenosum-like lesions in a healthy child after infection treated with antibiotics.

Abstract:  Ecthyma gangrenosum is a cutaneous infection associated most commonly with pseudomonal sepsis in the immunocompromised patient. We describe a previously healthy 4‐year‐old boy who developed ecthyma gangrenosum‐like lesions secondary to antibiotic treatment for possible streptococcal infection. The skin, ears, and extremities were involved. This presentation emphasizes the importance of awareness of the rare complication of ecthyma gangrenosum‐like lesions associated with non‐Pseudomonas bacterial infection treated with antibiotics, even in a previously healthy child.

Histochemical analysis of the chemical structure of blood group-related carbohydrate chains in serous cells of human submandibular glands using lectin staining and glycosidase digestion

Using lectin staining methods in combination with exo- and endo-glycosidase digestion procedures, we analyzed the chemical structure of different types of blood group-related substances in serous cells of formalin-fixed, paraffin-embedded human submandibular glands. Serous cells produced only H antigen; A and B antigens were not present, and the expression of H antigen is dependent on the secretor status of the tissue donor. Although reactivity with Ulex europaeus agglutinin I (UEA-I) was not markedly reduced by alpha-L-fucosidase digestion, an affinity for peanut agglutinin (PNA) was seen after fucosidase digestion in the cells from secretors. In those from nonsecretors, no PNA reactivity appeared after enzyme digestion. On the other hand, sialidase digestion elicited PNA reactivity in serous cells irrespective of the donors secretor status. PNA reactivity observed after fucosidase or sialidase digestion was susceptible to endo-alpha-N-acetylgalactosaminidase (endo-GalNAc-dase) digestion. SBA reactivity in UEA-I-negative cells from secretors, or in cells from fetuses and newborn infants, was markedly reduced by beta-galactosidase digestion. After galactosidase digestion, reactivity with Griffonia simplicifolia agglutinin II (GSA-II) appeared in the corresponding cells. This GSA-II reactivity was almost completely eliminated by subsequent beta-N-acetylhexosaminidase digestion. Whereas PNA reactivity in these cells was not reduced by beta-galactosidase treatment, it was significantly diminished by endo-GalNAc-dase digestion. These results suggest that at least two kinds of precursor disaccharides are produced in submandibular serous cells, i.e., SBA-reactive D-galactose-(beta 1-3,4)-N-acetyl-D-glucosamine and PNA-reactive D-galactose-(beta 1-3)-N-acetyl-D-galactosamine alpha 1-serine or threonine (O-glycosidically linked Type 3 chain or T antigen). Final fucosylation and synthesis of these two types of precursor chain appear to be under the control of the secretor gene.

Immunogold Labelling of Cytokines in Glomeruli in Children with Various Renal Diseases

Precise localization of cytokines such as transforming growth factor-β (TGF-β), tumor necrosis factor-α (TNF-α), interleukin (IL)-1 and IL-6 was observed in glomeruli using immunogold electron microscopy in 21 children with various types of renal diseases. The distribution pattern of these cytokines, as well as immunoglobulins, C3c and fibrinogen (Fg), was essentially confined to the electron-dense deposits (EDDs) regardless of their location. Frequency of positive labelling of each cytokine was different among various types of renal disorder, that is, TGF-β was found mainly in lupus nephritis (LN), membranous nephropathy and IgA nephropathy, TNF-α in LN, and IL-1 in Henoch-Schönlein purpura nephritis. IL-6 was detected only in 1 case of LN. TNF-α was also found in the cytoplasm of glomerular epithelial cells. Furthermore, in order to evaluate the relation of cytokines to mesangial expansion, extracellular matrix components such as type IV collagen, laminin and fibronectin were stained. The result was that there was no significant correlation between the signal intensity or distribution pattern of cytokines and that of extracellular matrix components. These findings indicate that these cytokines could be associated with the formation of EDDs together with immunoglobulins, C3c and Fg. The involvement of each cytokine in renal pathophysiology might also depend upon the type of renal disease. They also raise the possibility that the glomerular epithelial cells might produce or absorb TNF-α. However, these results did not show significant correlation between cytokine involvement and mesangial expansion.