bluuebunny/crossref_metadata_2025 huggingface dataset:
Non‐conservative substitutions distinguish previously uncharacterized HLA‐A molecules
Authors: Hickman H.D. , Cavett J.W. , Ellexson‐Turner M.E. , Sparkman J.N. , Bennett T.T. , Turner S. , Sidebottom D.A. , Trachtenberg E.A. , Confer D.L. , Hildebrand W.H.
Published: March 2003

Abstract: The extent of class I HLA polymorphism is not yet realized, and to provide a glimpse of the HLA‐A polymorphism which remains undetected, we have analyzed approximately 3,700 National Marrow Donor Program (NMDP) Donor/Recipient Pair Retrospective Study Samples with HLA‐A DNA sequence‐based typing (SBT). Seventeen new HLA‐A alleles were detected, with a total of 19 nucleotide substitutions distinguishing these new alleles from their closest HLA‐A relatives. Nearly all of the new alleles differ by single nucleotide substitutions; a majority of these substitutions can be explained by gene conversion events but 6 alleles likely originated by point mutation. Fifteen of the 19 nucleotide substitutions translate into amino acid differences in the molecule. Structurally, the inferred amino acid alterations were non‐conservative in terms of chemical property, and most substitutions were positioned in 1 or more of the specificity pockets which determine peptide binding. Although these new alleles were identified in a primarily Caucasian sample population, 9 of the 17 new HLA‐A alleles were found in samples of non‐Caucasoid origin. A new allele detection rate of 1 in approximately 200 individuals in our data set would, therefore, be higher in a non‐Caucasoid sample population. In summary, the single nucleotide substitutions that distinguish undetected HLA‐A alleles translate into functionally distinct HLA‐A molecules. Further studies of the role of HLA‐A in transplantation, in disease association, and in evolution must therefore accommodate the discovery of new alleles differing by single nucleotides.
Genomic diversity of natural killer cell receptor genes in three populations
Authors: Toneva M. , Lepage V. , Lafay G. , Dulphy N. , Busson M. , Lester S. , Vu‐Trien A. , Michaylova A. , Naumova E. , McCluskey J. , Charron D.
Published: March 2003

Abstract: We report the distribution of genes encoding 11 killer cell immunoglobulin‐like receptors (KIR) and 2 CD94:NKG2 receptors, in 32 Caucasians, 67 Australian Aborigines and 59 Vietnamese. The inhibitory and the activating KIR genes were found at different frequency in the three populations. No correlation was found between the polymorphism of the KIR genes and the HLA specificities of the tested samples. The most significant KIR associations were 2DL2 with 2DS2; 2DL2 with 2DS3 and 3DL1 with 2DS4 in all three study groups. In Caucasians and Vietnamese 2DS2 was associated with 2DS3 and 2DS1with 3DS1. KIR 2DL1 was strongly associated with three other KIRs: 2DL3, 3DL1 and 2DS4 in Aborigines. The distribution of the KIR phenotypes was different in the three populations. The AA1 phenotype was frequent in Vietnamese (42.4%) and Caucasians (31.2%), but very rare in Aborigines (1.5%). In contrast, the BB7 phenotype was very common for Aborigines (22.4%) and was absent in the two other groups. Our data demonstrate that different associations and putative KIR haplotypes could be distinguished in different populations.
Evidence for a novel polymorphism affecting both N‐linked glycosylation and ligand binding of the IgG receptor IIIB (CD16)
Authors: Yamamoto K. , Sugita N. , Kobayashi T. , Okuda K. , Van De Winkel J.G.J. , Yoshie H.
Published: March 2003

Abstract: Immunoglobulin G Fc receptor IIIb (FcγRIIIb) is constitutively expressed on neutrophils, and has three allelic forms: FcγRIIIb‐NA1, FcγRIIIb‐NA2, and FcγRIIIb‐SH. We identified two Japanese subjects in whom an A to G substitution at nt 221 changes asparagine (N) to serine (S) at amino acid position 45 in the FcγRIIIb‐NA2 gene. FcγRIIIb‐NA2‐specific monoclonal antibodies (GRM1 and PEN1) did not bind to mutant neutrophils, which lack an N‐linked glycosylation site. Furthermore, IgG3‐mediated neutrophil phagocytosis by mutant was slightly increased as compared to wild‐type donors (Note).
Polymorphism of human HLA‐DRB1 antigens generated by genetic exchange between DR2 (DRB1*15011) and DR6 (DRB1*1405) alleles: a novel DRB1 allele (DRB1*1437) identified in a Paiwan tribe member of Taiwan
Authors: Wu S. , Shiao Y.‐M. , Lai C.‐Y. , Lai S.‐M. , Chen S.‐P. , Sidebottom D.A. , Hildebrand W.H. , Tilanus M.G.J. , Chou F.‐C. , Tsai M.‐F.
Published: March 2003

Abstract: We report herein the identification of a new DRB1 allele using sequence‐based typing (SBT). This novel allele, HLA‐DRB1*1437, was found in an aboriginal individual from the Paiwan tribe in the southern part of Taiwan. This individual was typed by SBT method as having an HLA genotype of HLA‐A*02011/0203, HLA‐B*15011/3901, HLA‐DRB1*11011/1437, HLA‐DRB3*0202/0202, and HLA‐DPB1*0501/1301. This new allele differs from DRB1*1309 in the 5′‐end nucleotide sequence of polymorphic exon 2 at codon 16 (CAT→CAA; H16Q), codon 37 (AAC→TTC; R37F), codon 47 (TTC→TAC; F47Y), and codon 58 (GCC→GCT; both specify alanine). By sequence comparison, it was found that this new allele has a 5′‐end sequence (from amino acid residues 7 to 66) identical to that found in the DRB1*1405 allele and a 3′‐end sequence (from amino acid residues 58 to 94) identical to that found in the DRB1*15011 allele. Both DRB1*1405 and DRB1*15011 alleles have been identified among the Paiwan members (Note).
Twelve novel HLA‐B*15 alleles carrying previously observed sequence motifs are placed into B*15 subgroups
Authors: Hurley C.K. , Steiner N. , Gans C.P. , Kosman C , Mitton W. , Koester R. , Jones P. , Edson S. , Rizzuto G. , Hartzman R.J. , Ng J. , Rodriguez‐Marino S.G.
Published: March 2003

Abstract: Twelve new B*15 alleles are described. All of the known B*15 alleles are divided into subgroups based on serologic assignments and/or nucleotide sequence polymorphisms. These groups might be used as a reference for DNA‐based testing at an intermediate (i.e. “serologic”) level of resolution.
DPB1*8601, a previously unrecognized DPB1 variant in the Caucasoid population
Authors: Bengtsson M.
Published: March 2003

Abstract: A new, previously unrecognized DPB1* allele, DPB1*8601, was found in a Swedish family. The new allele was carried on the common North European haplotype HLA A1‐B8‐DR3. Both individuals carrying the new allele were initially typed as clear DPB1*4601,*6601 but after family studies and further typing with allele‐specific primers it was concluded that a new allele was present together with the common DPB1*0401. The new allele was investigated by direct sequencing of exon 2 in both forward and reverse directions employing intron primers combined with either an allele‐specific sense or anti‐sense biotinylated primer for bi‐directional sequencing. The new allele is identical to DPB1*1701 in the five first variable regions. In the sixth region, however, DPB1*8601 carries the GGPM motif shared by several common alleles such as DPB1*0201 and 0401and 0402.
The distribution of HLA class II susceptible/protective haplotypes could partially explain the low incidence of type 1 diabetes in continental Italy (Lazio region)
Authors: Petrone A. , Bugawan T.L. , Mesturino C.A. , Nisticò L. , Galgani A. , Giorgi G. , Cascino I. , Erlich H.A. , Di Mario U. , Buzzetti R.
Published: March 2003

Abstract: HLA class II is the primary susceptibility gene to type 1 diabetes and the analysis of HLA class II association could help to clarify the relative weight of genetic contribution to the incidence of the disease. Here we present an extensive typing for HLA class II alleles and their haplotypes in a homogenous population of type 1 diabetic patients (n=134) and controls (n=128) and in simplex (n=100) and multiplex families (n=50) from continental Italy (Lazio region). Among the various haplotypes tested, the DRB1*0301‐DQA1*0501‐DQB1*0201 was the most frequent found in type 1 diabetic patients and was transmitted in 82% of affected siblings, whereas DRB1*0402‐DQA1*0301‐DQB1*0302 appeared to have the highest odds ratio (10.4), this haplotype was transmitted in 96.3% of affected siblings, followed by DRB1*0405‐DQA1*0301‐DQB1*0302, DRB1*0405‐DQA1*0301‐DQB1*0201, DRB1*0401‐DQA1*0301‐DQB1*0302 and DRB1*0404‐DQA1*0301‐DQB1*0302. The following haplotypes showed a significant decreased transmission to diabetic siblings: DRB1*0701‐DQA1*0201‐DQB1*0303, DR2‐DQA1*01‐DQB1*0602, DR5‐DQA1*0501‐DQB1*0301. We suggest that the HLA DR/DQ haplotype/genotype frequencies observed could in part explain the low incidence of type 1 diabetes registered in Lazio region (8.1/100.000/year), for a number of reasons: i) the low frequency, in the general control population, of the most susceptible haplotypes and genotype for type 1 diabetes DRB1*0301‐DQA1*0501‐DQB1*0201 (14%), and DR4‐DQA1*0301‐DQB1*0302 (9%) and DRB1*0301‐DQA1*0501‐DQB1*0201/DR4‐DQA1*0301‐DQB1*0302 (0.8%) compared to other countries characterised by high incidence rate of the disease, Sardinia and Finland, respectively; ii) a significant lower ratio, in the control population, between the susceptible DRB1*0301‐DQA1*0501‐DQB1*0201 and the neutral DRB1*0701‐DQA1*0501‐DQB1*0201 haplotypes compared to the Sardinian population; iii) the high frequency of protection haplotypes/genotypes as the DR5‐DQA1*0501‐DQB1*0301, and DR5‐DQA1*0501‐DQB1*0301/DR5‐DQA1*0501‐DQB1*0301 very common in the control population of Lazio region and the DRB1*1401‐DQA1*0101‐DQB1*0503 haplotype.
Genotyping of human killer‐cell immunoglobulin‐like receptor genes by polymerase chain reaction with sequence‐specific primers: An update
Authors: Gómez‐Lozano N. , Vilches C.
Published: March 2003

Abstract: Killer‐cell Immunoglobulin‐like Receptors (KIR) help human natural killer (NK) cells counteract infections by pathogens that evade the immune system by inducing down‐regulation of HLA class I molecules in infected cells. KIRs are structural and functionally diverse receptors encoded by a family of polymorphic genes. The most extreme aspect of KIR polymorphism is the varying content of KIR‐genes in the genome of different individuals, as first demonstrated by KIR genotyping using the PCR‐SSP method. Knowledge on the KIR‐gene family has been recently expanded by the identification of new genes, pseudogenes and multiple gene variants, several of which escaped detection by the original genotyping technique. We present here an upgraded PCR‐SSP method for KIR genotyping that integrates recent achievements in the research of the diversity of this gene family. Our method permits detection of all known KIR genes and pseudogenes in a 16‐reaction set. Furthermore, an additional set of six reactions permits subtyping of KIR2DL5 variants, each of which shows well‐differentiated functional and genetic features1,2.
Optimizing vaccine design for cellular processing, MHC binding and TCR recognition
Authors: Sette A. , Newman M. , Livingston B. , McKinney D. , Sidney J. , Ishioka G. , Tangri S. , Alexander J. , Fikes J. , Chesnut R.
Published: March 2003

Abstract: In this review we describe the methods and processes that our group have developed while aiming to test and design multiepitope vaccines for infectious diseases and cancer. Testing the performance of vaccines composed of epitopes restricted by human leukocyte antigen (HLA) molecules is accomplished by in vitro antigenicity assays, as well as in vivo immunogenicity assays in HLA transgenics. The efficiency by which multiepitope vaccines are processed is optimized by spacer residues, which are designed to facilitate generation by natural processing of the various class I‐ and class II‐restricted epitopes. Methods and strategies to test and optimize HLA binding affinity, patient coverage from the vaccine construct, and TCR recognition of HLA/epitope complexes are also discussed.
HLA class II allele and haplotype frequencies in Koreans based on 107 families
Authors: Song E.Y. , Park M.H. , Kang S.J. , Park H.J. , Kim B.C. , Tokunaga K. , Akaza T. , Juji T.
Published: March 2003

Abstract: We have investigated the distribution of HLA class II alleles and haplotypes in 107 Korean families (207 parents and 291 children) for the HLA‐DRB1, DRB3/B4/B5, DQA1, DQB1 and DPB1 loci. Numbers of alleles observed for each locus were DRB1: 25, DQA1: 14, DQB1: 15, and DPB1: 13. Only two to three alleles were observed for the DRB3 (*0101, *0202, *0301), DRB4 (*0103, * 0103102 N), and DRB5 (*0101, *0102) loci. These alleles showed strong associations with DRB1 alleles: DRB3*0101 with DRB1*1201, *1301 and *1403; DRB3*0301 with DRB1*1202 and *1302; DRB3*0202 with DRB1*0301, *1101, *1401 and *1405; DRB5*0101 and *0102 were exclusively associated with DRB1*1501 and *1502, respectively. The seven most common DRB1‐DQB1 haplotypes of frequencies > 0.06 accounted for 52% of the total haplotypes. These haplotypes were exclusively related with the seven most common DRB1‐DRB3/B4/B5‐DQA1‐DQB1 haplotypes: DRB1*1501‐DRB5*0101‐DQA1*0102‐DQB1*0602 (0.085), DRB1*0405‐DRB4*0103‐DQA1*0303‐DQB1*0401 (0.082), DRB1*09012‐DRB4*0103‐DQA1*0302‐DQB1*03032 (0.082), DRB1*0101‐DQA1*0101‐DQB1*0501 (0.075), DRB1*0701‐DRB4*0103‐DQA1*0201‐DQB1*0202 (0.065), DRB1*0803‐DQA1*0103‐DQB1*0601 (0.065), and DRB1*1302‐DRB3*0301‐DQA1*0102‐DQB1*0604 (0.065). When these haplotypes were extended to the DPB1 locus, much diversification of haplotypes was observed and only one haplotype remained with a frequency of > 0.06: DRB1*0405‐DRB4*0103‐DQA1*0303‐DQB1*0401‐DPB1*0501 (0.062). Such diversification would have resulted from cumulated events of recombination within the HLA class II region, and the actual recombination rate observed between the HLA‐DQB1 and DPB1 loci was 2.3% (10/438 informative meioses, including 2 recombinants informative by analysis of TAP genes). Comparison of the distribution of DRB1‐DQB1 haplotypes with other populations revealed that Koreans are closest to Japanese people. However, Koreans share a few haplotypes with white people and Africans, which are rare in Japanese: DRB1*0701‐DQB1*0202 and DRB1*1302‐DQB1*0609. The results obtained in this study will provide useful information for anthropology, organ transplantation and disease association studies.
HLA polymorphism in a Majorcan population of Jewish descent: Comparison with Majorca, Minorca, Ibiza (Balearic Islands) and other Jewish communities
Authors: Crespí C. , Milà J. , Martínez‐Pomar N. , Etxagibel A. , Muñoz‐Saa I. , Priego D. , Luque A. , Pons J. , Picornell A. , Ramon M. , Castro J.A. , Matamoros N.
Published: March 2003

Abstract: ‘ Chueta’ was the name given to the Catholic descendants of Jewish victims of the last Spanish Inquisition process in Majorca Island in the western Mediterranean. We have studied the allele distribution of HLA‐A, ‐B, ‐Cw, ‐DRB1 and ‐DQB1 loci of 103 random, healthy, unrelated individuals belonging to the ancient Majorcan Jewish community, known locally as Chuetas, and 589 individuals from the Balearic population selected because of their typical Balearic – Majorca, Minorca or Ibiza – lineages and according to their ancestor's place of birth. Our aim was to establish the genetic relationship between Majorcan Chuetas, and Balearic and other Jewish and Mediterranean populations. Our results have shown that, to a remarkable extent, they have retained their biological identity, with a unique pattern, in terms of gene and haplotype frequencies, separate from the other populations of Majorca. The Chuetas were found to be more related to Moroccan and Libyan Jews than other Majorcans. Characteristic Jewish haplotypes, A26‐B38‐DRB1*13, A24‐B38‐DRB1*11, A1‐B52‐DRB1*15/16, were found in our study. Some peculiarities were observed in the distribution of common haplotypes among the three main Balearic Islands. The Ibizan population was genetically different from the other Balearic populations, with a high frequency of some haplotypes, for example, A29‐Cw*16‐B44‐DRB1*07‐DQB1*03; A1‐Cw*07‐B8‐DRB1*03‐DQB1*02. We also found a new haplotype, A25‐Cw*12‐B39‐DRB1*11‐DQB1*03(3.5%), in Ibizans and a more limited variability in the HLA alleles that were expressed, perhaps because of genetic isolation. The genetic diversity of the populations from Majorca and Minorca were similar and more related to the mainland Spanish population.
Association of HLA‐DR and type II collagen autoimmunity with Meniere's disease
Authors: Koo J.‐W. , Oh S.H. , Chang S.O. , Park M.H. , Lim M.J. , Yoo T.‐J. , Kim C.S.
Published: March 2003

Abstract: To investigate HLA‐associated genetic susceptibility to Meniere's disease in relation to type II collagen (CII) autoimmunity status, HLA‐DRB1 genotyping and ELISA measurement of anti‐CII antibody were performed in 41 Korean patients with Meniere's disease. In the anti‐CII positive subgroup (20%) of patients, the frequency of HLA‐DRB1*0405 was significantly increased (uncorrected) compared with both controls (63% vs 16%) and anti‐CII negative patients (63% vs 12%). In the anti‐CII negative subgroup, HLA‐DRB1*1201 was significantly increased (uncorrected) (27% vs 10%) and DRB1*13 was decreased (6% vs 24%) compared with controls; these alleles appeared to confer susceptibility and resistance to the development of the disease. Association of HLA‐DRB1*0405 with anti‐CII positive Meniere's disease in this study suggests that it shares a specific HLA‐DR sequence, QRRAA, as a genetic susceptibility factor with the anti‐CII positive rheumatoid arthritis. In conclusion, whilst type II collagen autoimmunity may have a partial role in Meniere's disease, different HLA‐DR alleles may also be associated with either susceptibility or resistance to the development of the disease in relation to anti‐CII antibody status.
Characterization of epitope regions of thyrotropin β‐subunit recognized by the monoclonal antibodies mAb279 and mAb299: a chimeric peptide approach
Authors: Gomme P.T. , Thompson P.E. , Whisstock J. , Stanton P.G. , Hearn, M. T. W
Published: March 2003

Abstract: This investigation describes the design, synthesis and evaluation of chimeric peptides related to the bovine thyrotropin β‐subunit, bTSHβ. The structures of these chimeric peptides were derived from investigations with linear peptides and sequence alignment studies, in association with a homology model of TSHβ developed from the hCG X‐ray crystallographic structure. The structures of these chimeric peptides comprised β‐turn regions of loop L1[bTSHβ(14‐20)] and loop L3[bTSHβ(65‐72)] held in close proximity by a bis‐β‐alanine linker and the disulfide bond bTSHβ[Cys16‐Cys67]. Linear and cyclic chimeric peptides were evaluated in immunochemical assays for their ability to inhibit the binding of radio‐iodinated bTSHβ[125I‐bTSHβ] to the monoclonal antibodies, mAb279 and mAb299. Previously, mAb279 and mAb299 have been shown to recognize epitopes accessible on the surface of TSHβ that lie in close proximity to the TSH receptor‐binding site. The results indicate that these chimeric peptides can specifically inhibit in a dose‐dependent manner the binding of 125I‐bTSHβ to mAb299, while having a lesser effect on the binding with mAb279. Based on these results, it can be concluded that the bTSHβ‐epitope recognized by mAb299 involves contributions from amino residues from the β‐turn regions of the L1 and L3 loops of TSHβ, and that these loop regions flank part of the receptor binding site of the bTSH β‐subunit.
De novo design: backbone conformational constraints in nucleating helices andβ‐hairpins
Authors: Balaram P.
Published: March 2003

Abstract: A modular approach to synthetic protein design is being developed using conformationally constrained amino acid as stereochemical directors of polypeptide chain folding. An overview of studies aimed at constructing peptide helices using α,α‐dialkyated residues and β‐hairpins using
d‐Pro as a turn nucleator is presented. The construction of helix‐helix motifs and three‐ and four‐stranded structures has been achieved using non‐protein amino acids to stabilize specific elements of secondary structures.
Channel‐forming, self‐assembling, bishelical amphiphilic peptides: design, synthesis and crystal structure of Py(Aibn)2, n = 2, 3, 4
Authors: Ranganathan D. , Kurur S. , Kunwar A.C. , Sarma A. V. S. , Vairamani M. , Karle I.L.
Published: March 2003

Abstract: The design, synthesis, characterization and self‐assembling properties of a new class of amphiphilic peptides, constructed from a bifunctional polar core attached to totally hydrophobic arms, are presented. The first series of this class, represented by the general structure Py(Aibn)2 (Py = 2,6‐pyridine dicarbonyl unit; Aib = α, α′‐dimethyl glycine; n = 1–4), is prepared in a single step by the condensation of commercially available 2,6‐pyridine dicarbonyl dichloride with the methyl ester of homo oligoAib peptide (Aibn‐OMe) in the presence of triethyl amine. 1H NMR VT and ROESY studies indicated the presence of a common structural feature of 2‐fold symmetry and an NH…N hydrogen bond for all the members. Whereas the Aib3 segment in Py(Aib3)2 showed only the onset of a 310‐helical structure, the presence of a well‐formed 310‐helix in both Aib4 arms of Py(Aib4)2 was evident in the 1H NMR of the bispeptide. X‐ray crystallographic studies have shown that in the solid state, whereas Py(Aib2)2 molecules organize into a sheet‐like structure and Py(Aib3)2 molecules form a double‐stranded string assembly, the tetra Aib bispeptide, Py(Aib4)2, is organized to form a tetrameric assembly which in turn extends into a continuous channel‐like structure. The channel is totally hydrophobic in the interior and can selectively encapsulate lipophilic ester (CH3COOR, R = C2H5, C5H11) molecules, as shown by the crystal structures of the encapsulating channel. The crystal structure parameters are: 1b, Py(Aib2)2, C25H37N5O8, sp. gr. P212121, a = 9.170(1) Å, b = 16.215(2) Å, c = 20.091(3) Å, R = 4.80; 1c, Py(Aib3)2, C33H51N7O10·H2O, sp. gr. P, a = 11.040(1) Å, b = 12.367(1) Å, c = 16.959(1) Å, α = 102.41°, β = 97.29°, γ = 110.83°, R1 = 6.94; 1 da, Py(Aib4)2⋅et ac, C41H65N9O12⋅1.5H2O·C4H8O2, sp. gr. P, a = 16.064(4) Å, b = 16.156 Å, c = 21.655(5) Å, α = 90.14(1)°, β = 101.38(2)°, γ = 97.07(1)°, Z = 4, R1 = 9.03; 1db, Py(Aib4)2⋅amylac,C41H65N9O12⋅H2O ·C7H14O2, P21/c, a = 16.890(1) Å, b = 17.523(1) Å, c = 20.411(1) Å, β = 98.18 °, Z = 4, R = 11.1 (with disorder).
Immunological evaluation of Escherichia coli‐derived hepatitis C virus second envelope protein (E2) variants
Authors: Dueñas‐Carrera S. , Viña A. , Garay H.E. , Reyes O. , Alvarez‐Lajonchere L. , Guerra I. , González L.J. , Morales J.
Published: March 2003

Abstract: Two variants of the hepatitis C virus (HCV) E2 envelope protein, lacking the C‐terminal domain and comprising amino acids 458–650 (E2A) and 382–605 (E2C), respectively, were efficiently produced in BL21 (DE3) Escherichia coli cells. E2A and E2C were used to immunize mice. The E2C variant induced the maximal mean antibody titer. Anti‐E2C mouse sera reacted mainly with E2 synthetic peptides covering the 70 amino acid N‐terminal region of the E2 protein. Moreover, a panel of anti‐HCV positive human sera recognized only the E2C protein (28.2%) and the synthetic peptide covering the HVR‐1 of the E2 protein (23.1%). These data indicate the existence of an immunologically relevant region in the HVR‐1 of the HCV E2 protein.
Partial [αMe]Aun scan of [l‐Leu11‐OMe]‐trichogin GA IV, a membrane active synthetic precursor of the natural lipopeptaibol
Authors: Peggion C. , Moretto V. , Formaggio F. , Crisma M. , Toniolo C. , Kamphuis J. , Kaptein B. , Broxterman Q.B.
Published: March 2003

Abstract:We synthesized using solution‐phase methods three analogs of [l‐Leu11‐OMe] trichogin GA IV, a membrane active synthetic precursor of the lipopeptaibol antibiotic in which the N‐terminaln‐octanoyl group and each of the three Aib residues in positions 1, 4 and 8 are replaced by an acetyl group and the lipophilic Cα,α‐disubstituted glycinel‐(αMe)Aun, respectively [partial (αMe)Aun scan]. FT‐IR absorption and CD analyses unequivocally show that the main three‐dimensional structural features of [l‐Leu11‐OMe] trichogin GA IV are preserved in the analogs. Also, [l‐Leu11‐OMe] trichogin GA IV and the three Nα‐acetylatedl‐(αMe)Aun analogs exhibit strictly comparable membrane‐modifying properties. Taken together, these results strongly favor the conclusion that a shift of the long hydrocarbon moiety from the Nα‐blocking group to the side‐chain of the 1, 4 or 8 residue does not have any significant effect on the conformational properties or the membrane activity of [l‐Leu11‐OMe] trichogin GA IV and, by extension, of the natural lipopeptaibol.
A new antifungal peptide from rice beans
Authors: Ye X Y , Ng T B
Published: March 2003

Abstract: A peptide, possessing a molecular mass of 5 kDa and demonstrating remarkable sequence homology to the cowpea 10 kDa protein precursor and garden pea disease resistance response protein, was isolated from rice bean seeds. The peptide was adsorbed on CM‐Sepharose and Affi‐gel blue gel. It inhibited mycelial growth in the fungi Botrytis cinerea, Fusarium oxysporum, Rhizoctonia solani and Mycosphaerella arachidicola. It stimulated incorporation of methyl [3H] thymidine into mouse splenocytes, inhibited the activity of human immunodeficiency virus type 1 reverse transcriptase and suppressed translation by rabbit reticulocyte lysate.
Roles of disulfide bridges in scorpion toxin BmK M1 analyzed by mutagenesis
Authors: Sun Y.‐M. , Liu W. , Zhu R.‐H. , Wang D.‐C. , Goudet C. , Tytgat J.
Published: March 2003

Abstract: The unique fold of scorpion toxins is a natural scaffold for protein engineering, in which multiple disulfide bonds are crucial structural elements. To understand the respective roles of these disulfide bridges, a mutagenesis analysis for the four disulfide bonds, 12–63, 16–36, 22–46 and 26–48, of a representative toxin BmK M1 from the scorpion Buthus martensii Karsch was carried out. All cysteines were replaced by serine with double mutations. The recombinant mutants were expressed in the Saccharomyces cerevisiae S‐78 system. Toxic activities of the expressed mutants were tested on ICR mice in vivo and on neuronal Na+ channels (rNav1.2) by electrophysiological analysis. Recombinant variants M1 (C22S,C46S) and M1 (C26S,C48S) were not expressed at all; M1 (C16S,C36S) could be expressed at trace levels but was extremely unstable. Variant M1 (C12S,C63S) could be expressed in an amount comparable with that of unmodified rBmK M1, but had no detectable bioactivities. The results indicated that among the four disulfide bonds for long‐chain scorpion toxins, loss of either bridge C22−C46 or C26−C48 is fatal for the general folding of the molecule. Bridge C16−C36 mainly contributes to the global stability of the folded scaffold, and bridge C12−C63 plays an essential role in the functional performance of scorpion toxins.
Clonal accumulation of T cells bearing Vβ6 T‐cell receptor in chronic inflammatory periodontal disease
Authors: Ohsawa Y. , Yamazaki K. , Nakajima T. , Hara K.
Published: March 2003

Our previous study demonstrated that among the various T‐cell receptor Vβ gene segments, T‐cell receptor Vβ6 gene–bearing T cells are predominant in periodontitis lesions. To explore the clonality of T cells expressing Vβ6 T‐cell receptor, which is determined by the heterogeneity of the complementarity‐determining region 3(CDR3), Vβ6‐Cβ polymerase chain reaction products derived from gingival tissue and peripheral blood of periodontitis patients were analyzed by single‐strand conformation polymorphism and nucleotide sequence. Both techniques provided quite similar results in terms of the number of accumulated clones in which clonal accumulation of T‐cell receptor Vβ6‐bearing T cells was found in most periodontitis lesions but not in peripheral blood. From the analysis of deduced amino acid sequences, a possible conserved amino acid residue in the CDR3 region of the periodontitis lesion‐derived sequences was found in most patients. This conserved amino acid motif however, was not identified. Furthermore, skewed Jβ gene segment usage was observed for expanded clones from periodontitis lesions. Our results suggest that T cells infiltrating periodontitis lesions are responding to a restricted number of antigens or epitopes.
Isolation and identification of Prevotella tannerae from endodontic infections
Authors: Xia T. , Baumgartner J. C. , David L. L.
Published: March 2003

Black‐pigmented bacteria are often isolated from endodontic infections. Five strains of black‐pigmented bacteria isolated from endodontic infections could not be identified in our laboratory. The purpose of this study was to sequence the 16S rRNA gene of the five unknown isolates and identify the organisms. The 16S rRNA genes from the unknown organisms were cloned, sequenced, and determined to be Prevotella tannerae. In addition, samples from endodontic infections were surveyed for the presence of the organism. When 118 samples from endodontic infections were examined using polymerase chain reaction with specific primers for P. tannerae, 60% of the samples were positive for the presence of the organism. This suggests that P. tannerae is commonly present in endodontic infections and could be a potential pathogen.
Kinetics of KB and HEp‐2 cell responses to an invasive, cytolethal distending toxin‐producing strain of Actinobacillus actinomycetemcomitans
Authors: DiRienzo J. M. , Song M. , Wan L. S. Y. , Ellen R. P.
Published: March 2003

The periodontal pathogen Actinobacillus actinomycetemcomitans produces cytolethal distending toxin (CDT), a complex multicomponent toxin that arrests the growth of many types of eukaryotic cell. The kinetics of the effects of CDT‐containing extracts, from an invasive strain of this bacterium, were examined on epithelial‐like cells routinely used in invasion studies. Both KB and HEp‐2 cells were exquisitely sensitive to the effects of the CDT with TD50 of 30 and 300 pg of total bacterial protein, respectively. Initial cell morphology changes were relatively rapid, occurring within the first 13 h of exposure. CDT‐treated KB cells increased in size to 4–5 times the size of untreated controls. Cytotoxicity was irreversible when attached cells were incubated, for a minimum of 120 min, with nanogram quantities of CDT‐containing extract. As cultures aged, the cells became more resistant to the effects of the CDT‐containing extracts. These findings have important implications for understanding the ability of A. actinomycetemcomitans to invade and multiply in epithelial cells.
Cytokine production in response to endodontic infection in germ‐free mice
Authors: Ribeiro Sobrinho A. P. , De Melo Maltos S. M. , Farias L. M. , De Carvalho M. A. R. , Nicoli J. R. , De Uzeda M. , Vieira L. Q.
Published: March 2003

This study evaluated the cytokine profiles (type 1 or type 2) that are triggered by and modulate endodontic periapical infections in the root canal system of germ‐free mice. Microorganisms isolated from two patients with pulpal necrosis were inoculated into two groups of experimental animals: group I (Gemella morbillorum) and group II (Bifidobacterium adolescentis, Fusobacterium nucleatum and Clostridium butyricum). In vitro, G. morbillorum induced type 1 cytokine synthesis, while the modulation processed in vivo seemed to have the opposite effect, with a reduction in the basal levels of IL‐12 and IFN‐γ, IL‐4‐independent down‐modulation. In vitro, microorganisms from group II, in poly‐infection, induced a reduction of type 1 cytokine levels from day 10 to day 20, which seemed to be modulated via IL‐4. In vivo, however, a predominance of the immune response to one species over the others occurred.
Prevalence of parentally perceived adverse reactions to food in young children
Authors: Eggesbø Merete , Halvorsen Ragnhild , Tambs Kristian , Botten Grete
Published: March 2003

A substantial number of parents perceive that their children have adverse reactions to food, but it is well documented that objective assessments agree with only one‐quarter to one‐half of parentally reported reactions. In order to prevent wrong diagnoses and curtail unnecessary or inadequate diets, primary health care providers need to deal with the parental perception of adverse reactions to food. A description of the prevalence and pattern of parentally perceived adverse reactions to food in children is needed to meet this challenge. The aim of the present study was to estimate the prevalence, incidence and cumulative incidences of parentally perceived adverse reactions to food in children younger than 2 years of age, and to study the duration of the reactions. A population‐based cohort of 3623 children born in Norway was followed from birth until the age of two. At 6‐month intervals, the parents completed questionnaires regarding the occurrence and type of any reaction to food. Information was available on the outcome measure at all age points for 77.4% of the families and these were used in the analyses; 3.8% of the cohort were entirely lost to follow‐up. The cumulative incidence of adverse reactions to food was 35% by age two. Fruits, milk and vegetables accounted for nearly two‐thirds of all reported reactions. Milk was the single food item most commonly incriminated, the cumulative incidence being 11.6%. The cumulative incidences of reported reactions to fruits and vegetables were 20.4% and 7.3%, respectively, with citrus fruits, strawberry and tomatoes as the most common food items in these groups. The cumulative incidences were less for food reactions associated with eggs (4.4%), fish (3%), nuts (2.1%) and cereals (1.4%). The duration of the reactions was short – approximately two‐thirds of the reactions were not reported again 6 months later. However, the probability of remission depended on the food item concerned, the age at onset of reactions, and whether the reaction had been reported previously or not. Adverse reactions to food are reported by the parents of one‐third of children in Norway before the age of two. The most striking feature of this study is the short duration of the food reactions, as approximately two‐thirds of the reactions are not reported again 6 months later. Nevertheless, the high frequency of reactions attributable to milk is of concern. Milk is an important part of the Norwegian diet for children, and if removed from the diet its nutritional value is not easily replaced. Further studies are needed to assess the degree to which parents alter the diet of their children based upon perceived reactions to food.
Interleukin‐5 and interleukin‐8 in relation to eosinophils and neutrophils in nasal fluids from school children with seasonal allergic rhinitis
Authors: Benson Mikael , Strannegård Inga‐lisa , Wennergren Göran , Strannegård Örjan
Published: March 2003

The objectives of this study were to measure interleukins 5 and 8 (IL‐5 and IL‐8) in relation to eosinophils and neutrophils, in nasal lavage fluids from 60 school children with allergic rhinitis, and to determine the influence of treatment with a topical steroid (budesonide) on the levels of the two cytokines. Highly sensitive enzyme immunoassays were used to analyze IL‐5 and IL‐8. IL‐5 levels and relative eosinophil counts in nasal lavage fluid increased significantly in patients with allergic rhinitis during the pollen season, compared with values obtained before the start of the season, and decreased significantly after treatment with budesonide. By contrast, no significant changes in IL‐8 or neutrophils were found during the pollen season, nor did they decrease following treatment. In the untreated patients, IL‐5 levels correlated significantly with eosinophil counts but not with neutrophil counts, whereas IL‐8 levels correlated with neutrophil counts but not with eosinophil counts. After budesonide treatment, the correlation between IL‐8 and neutrophils remained, and a correlation between IL‐8 and eosinophils emerged. These findings support the concepts that IL‐5 has a key role in regulating eosinophils and that IL‐8 is important for the regulation of neutrophils. Whereas IL‐5 and relative eosinophil counts are profoundly affected by topical steroid treatment, IL‐8 and neutrophils are not demonstrably affected by such treatment. It is possible that neutrophils, through the release of IL‐8, could be chemotactic for eosinophils in steroid‐treated patients.
Use of a pocket‐sized turbine spirometer in monitoring exercise‐induced bronchospasm and bronchodilator responses in children
Authors: Kannisto Senja , Vanninen Esko , Remes Kyllikki , Korppi Matti
Published: March 2003

For field studies of asthma, portable hand‐held pulmonary function testing devices are required. Other than for peak flow measurements, little has been done to validate their use in children. Fifty children aged 5–15 years having asthma symptoms were examined using an exercise challenge (8 min free running outdoors) and a bronchodilation test (salbutamol inhalation at a dose of 0.15 mg/kg). Pulmonary function was measured with a turbine spirometer, with a Wright peak flow meter (WPEF) and with a flow–volume spirometer (FVS). A fall of 15% or more in WPEF associated with wheezing or cough was considered diagnostic for bronchial hyper‐responsiveness to exercise (BHRE). A rise of 15% or more from baseline in WPEF after salbutamol inhalation was considered as a positive bronchodilator response (BDR). BHRE was present in 16 children (32%). Using the limit of a 15% or greater fall in FEV1, turbine spirometry identified 12 as BHRE‐positive and no additional cases, giving a sensitivity of 75% and a specificity of 100%. The turbine spirometer showed lower FEV1 values than the FVS, the difference increasing with airway obstruction. BDR was positive in eight children (16%). Using the limit of a 10% or greater rise in FEV1, turbine spirometry was positive in six cases. FEV1 measured by turbine spirometry could not be used interchangeably with conventional FVS. However, the turbine spirometer offers the possibility to measure FEV1 repeatedly in field conditions, such as during exercise challenges outdoors.
The effect of high‐efficiency and standard vacuum‐cleaners on mite, cat and dog allergen levels and clinical progress
Authors: Popplewell E.J. , Innes V.A. , Lloyd‐Hughes S. , Jenkins E.L. , Khdir K. , Bryant T.N. , Warner J.O. , Warner J.A.
Published: March 2003

The major triggers for allergic asthma are exposure to allergens of the house dust mite, Dermatophagoides pteronyssinus, and of pets. Unfortunately studies of techniques designed to reduce house dust mite and pet allergens have had mixed results. However, new so‐called ‘improved’ products continue to appear on the market and require subjective evaluation. The homes of 60 house dust mite‐allergic patients were studied to compare the effects of high‐efficiency and standard vacuum‐cleaners on allergen concentration. Der p 1 (house dust mite), Fel d 1 (cat) and Can f 1 (dog) allergens were measured in four separate locations in each home. Clinical analysis was by lung function, bronchodilator usage and histamine challenge techniques. There was a significant reduction in Fel d 1 (ng/m2) in dust samples from the living‐room carpet (p = 0.046), bedroom carpet (p = 0.003) and mattress (p = 0.013) and living‐room sofa (p = 0.005) after 12 months of using the high‐efficiency cleaners, but only in the mattress sample using the standard cleaners (p = 0.014). Can f 1 (ng/g dust) was reduced in the mattress sample after using the high‐efficiency vacuum‐cleaners (p = 0.028), but not at other sites. Der p 1 levels were not significantly changed over this period. Clinically, patients in the high‐efficiency group showed improvements in peak expiratory flow rate (PEFR) (p = 0.004), FEV1 (p = 0.026) and bronchodilator usage (p = 0.005) after 12 months. When the cat‐sensitive patients were analyzed separately, improvements in histamine PC20 (p = 0.039) were also seen. Reducing Fel d 1 concentrations, in the absence of any change in Der p 1 concentrations, can produce significant improvements in the lung function of atopic, asthmatic patients. This effect was primarily achieved in those patients with cat sensitivity, but who did not possess a cat themselves.
What are the candidate groups for pharmacotherapeutic intervention to prevent asthma?
Authors: De Longueville M.
Published: March 2003

Despite the development of many new therapies for the treatment of asthma, the prevalence of this disease is still increasing in many areas of the world. Today no intervention is able to completely cure asthma but chronic therapies could decrease its severity. Moreover, asthma is one of the most common chronic diseases of childhood and its pharmacoeconomic burden is huge. Epidemiologic studies have identified some of the major factors involved in the pathogenesis and evolution of asthma. Several prevention programs have been developed in different countries with various success rates. Most of those interventions were based on allergen avoidance. From studies aimed at controlling early asthma and from epidemiologic data, we have learned to identify high‐risk groups, e.g, the atopic child with allergic asthma, with a family history of asthma or allergy‐related disease and early sensitization to aeroallergens. Only a few prospective studies aimed at preventing the onset of asthma have been published. With ketotifen, Iikura et al. could prevent the onset of asthma after a 1‐year period in patients suffering from atopic dermatitis. Another study has been published by Bustos et al. concerning children with a family history of allergy and high total IgE levels. Those studies involved about 100 patients. No follow‐up data has been published for either of them. Recently, the first results from the ETAC® (Early Treatment of the Atopic Child) trial have been reported. This study involved 817 atopic children with atopic dermatitis and a family history of atopy: cetirizine halved the number of patients developing asthma in the subgroups (200 children) sensitized to house dust mite (51.5% versus 28.6%) or pollen (58.8% versus 27.8%). The optimal target for pharmaceutical intervention to prevent asthma would seem to be high risk patients: children with atopic dermatitis, a family history of asthma or atopic disease and early sensitization to aeroallergens. Primary prevention in whole populations (e.g. starting even before the onset of atopic dermatitis or allergen sensitization) does not at present appear to be a realistic approach.
Immunoglobulin G subclass concentrations and infections in children and adolescents with severe asthma
Authors: De Moraes Lui Cleonir , Oliveira Lea Campos , Diogo Constância Lima , Kirschfink Michael , Grumach Anete Sevciovic
Published: March 2003

It was the aim of this study to investigate possible dysfunctions of the humoral immune system in asthmatic children with frequent respiratory infections. Forty‐one severe asthmatics (7–15 years of age), classified according to the Second Brazilian Consensus in Asthma (1998), were divided into two groups: group I (n = 12) had recurrent respiratory infections; and group II (n = 29) were without recurrent respiratory infections. Immunoglobulin (Ig)G, IgA and IgM levels (nephelometry), and IgE (radioimmunoassay) and IgG subclasses (enzyme‐linked immunosorbent assay), were evaluated using standard methods. Asthmatics with recurrent infections presented with worse clinical evolution, an increased number of hospital admissions, and a higher need of medication than the children without recurrent infections. There were no significant differences between the mean values of IgG, IgA or IgM levels, or IgE or IgG subclasses, in patients of both groups. A complete IgA deficiency was detected in two patients of group I (one was associated with IgG subclass deficiency). Deficiency of one or more IgG subclasses was verified in eight of 12 (66%) children from group I and in 16/29 (55%) from group II. The following deficiencies were found in both groups: IgG3 (10/41), IgG4 (three of 41), IgG2 (two of 41), IgG1 (one of 41), IgG3‐IgG4 (four of 41), IgG1‐IgG3 (two of 41), and IgG1‐IgG3‐IgG4 (one of 41). There were a higher proportion of children with low IgG4 levels in group I than in group II (p = 0.01). To conclude, IgA and IgG subclass deficiencies were detected in both severely asthmatic groups, with a predominance of IgG3 subclass deficiency. However, low IgG subclass levels appear not to be a suitable predictor of the development of infections in asthmatic children.
Immunodeficiency with recurrent panlymphocytopenia, impaired maturation of B lymphocytes, impaired interaction of T and B lymphocytes, and impaired integrity of epithelial tissue: A variant of idiopathic CD4+ T lymphocytopenia?
Authors: Von Bernuth Horst , Knöchel Birgit , Winkler Ulf , Roesler Jochen , Schlesier Michael , Gahr Manfred
Published: March 2003

Idiopathic CD4+ T lymphocytopenia (ICL) has been defined as a cause of immunodeficiency with a variable clinical course and an unknown etiology. Here we describe a now 18‐year‐old boy with ICL, chronic mucocutaneous candidiasis (CMC), recurrent abscesses, and relapsing aphthous and ulcerous lesions. In addition to ICL the patient frequently showed a panlymphocytopenia. An increased percentage of γ+δ+ T lymphocytes and IgD+ IgM+ B lymphocytes, and a decreased percentage of CD21+ B lymphocytes, were observed. In vitro assays showed normal T‐cell responses to candidin and T‐cell mitogens, but impaired B‐cell responses to pokeweed mitogen (PWM). B‐cell maturation after stimulation with Staphylococcus aureus Cowan I (SAC) and interleukin 2 (IL‐2) was nearly normal. The clinical course of the patient improved substantially on administration of constant low‐dose therapy with fluconazole.
Longitudinal gonadal function after bone marrow transplantation for acute lymphoblastic leukemia during childhood
Authors: Mayer E. I. E. , Dopfer R. E. , Klingebiel T. , Scheel‐walter H. , Ranke M. B. , Niethammer D.
Published: March 2003

Abstract: Total body irradiation and high‐dose chemotherapy, applied as a preparatory regimen for bone marrow transplantation (BMT) in children with acute lymphoblastic leukemia (ALL), are particularly hazardous to the gonads and, in addition, can impair hypothalamo–pituitary–gonadal control. Longitudinal data on pubertal development and gonadal function in these patients are limited. Twenty‐one ALL patients (15 males, 6 females) who had successfully undergone allogeneic BMT before puberty (age at BMT: 3.4–12.3 yr) were followed up in University Children’s Hospital, Tübingen, Germany over 2 (minimum) to 14 (maximum) years. Tanner development scores, serum testosterone and estradiol, basal follicle‐stimulating hormone (FSH) and luteinizing hormone (LH) were analyzed. During pubertal age, the levels of FSH and LH rose consecutively, resulting in noticeably elevated serum concentrations in 100% and 89%, respectively, of boys older than 14 years and in 75% and 75%, respectively, of girls older than 13 years. Nevertheless, pubertal development has been normal in all patients except in one boy and two girls who required substitution with sexual steroids, as timely puberty (i.e. boys < 14 years, girls < 13 years) did not start. In males with normal puberty, testosterone levels, however, were found to be low–normal. In conclusion, after BMT preceded by total body irradiation for childhood ALL, gonadal function is impaired. Even if normal pubertal development occurs, deficiencies in long‐term endocrine function cannot be ruled out. In view of the high FSH levels, the prognosis for fertility is doubtful.