Search

In this study, a spray-assisted synthetic method for preparation of Ni-rich Li [NixCoyMn1-x-y]O2(NCM) cathode microspheres is introduced. Unlike the co-precipitation method, which necessitates pH control, the use of complexing agent, and further lithiation step, the spray-assisted approach can produce Li-containing precursors with homogeneous elemental distribution in a few seconds. To overcome the high energy density loss arising from the morphological traits of the hollow/porous microspheres produced from the spray process, a two-step spraying methodology is adopted. Planetary ball milling efficiently pulverizes the spray-pyrolyzed product, which is then dispersed in an aqueous solution to form colloids. Spray drying and subsequent oxidation of the colloidal solution yield ant-cave-structured NCM microspheres with fine primary particles. By simply changing the stoichiometry of the metal salts dissolved in the aqueous solution, NCM cathodes with the desired composition (NCM622 and NCM811) are obtained. Additionally, a Li-reactive coating layer is introduced on the surface of the fine particles comprising NCM microspheres by a 10-min gas-phase coating method. The delicate design of NCM622 cathode with a coating layer enables stable cycle performance (capacity retention of 82.0 % after the 150th cycle) and high rate capability (136.8 mA h g−1at 10 C) when operated under high-voltage conditions (2.5–4.5 V).

For patients who do not have a suitable human leukocyte antigen (HLA)-matched family donor, unrelated donor registries of adult volunteers and banked umbilical cord blood (UCB) units provide the potential for successful haemopoietic stem-cell transplantation. The size and genetic composition of such registries determines the proportion of patients who will be able to find a suitable match. We aimed to assess the proportion of positive matches for Indian patients.

The T-box is a strongly conserved protein domain, 174 to 186 amino acids in length, that binds DNA. Many genes from many species have been shown to encode T-box domain-containing proteins. Here we report the cloning and characterization of a novel T-box gene, TBX21. The human cDNA contains an open reading frame encoding a 535-amino-acid protein with a predicted molecular mass of 58.3 kDa. Except for the T-box sequence, database searches revealed no significant homology to any known sequences at the nucleotide or protein level. In addition to the human cDNA sequence, we report the cDNA sequence of the murine homologue, the structure and organization of the murine Tbx21 gene, and its localization to mouse chromosome 11. TBX21 expression was detected in peripheral blood lymphocytes, spleen, lung, and natural killer cells.

High incidences of graft failure and graft-versus-host disease in the recipients of bone marrow transplantations (BMT) from unrelated donors (URD) may reflect the existence of allelic disparities between the patient and the URD despite apparent HLA identity at HLA-A, HLA-B, and HLA-DRB1 loci. To identify the extent and pattern of allelic disparities at HLA-A and HLA-B loci, 128 patients and 484 potential URD were evaluated by DNA typing. DNA typing for HLA-A, HLA-B, and HLA-DRB1 was performed at Memorial Sloan Kettering Cancer Center. HLA-A and HLA-B serotyping on URD was provided by the registries. By original typing (serology for HLA-A and HLA-B; DNA typing for DRB1) 187, 164, and 133 URD were 6/6, 5/6, and 4/6 matches, respectively. Following DNA typing, however, only 52.9% of the originally 6/6 matched URD remained 6/6, while 38.5%, 7.5%, and 1.1% were found to be 5/6, 4/6, and 3/6 matches. The level of disparity was higher in the originally 5/6 (P< .01) and 4/6 (P < .01) matched URD. A higher level of disparity was seen for HLA-B as compared to HLA-A. In addition, a serotype related variation was also noticed. For example, 24.1% of HLA-A2 and 60.1% of HLA-B35 seromatched URD were genotypically disparate, but no disparities were seen for HLA-A1 and HLA-B8. A higher percentage of HLA-A (67.4%) compared with HLA-B (35.4%) serologic homozygous URD remained genotypically homozygous (P = .01). The level of allelic disparity was lower (P < .01 for 6/6; P = .02 for 5/6) if the patient had one of the 15 most common haplotypes (A1B8DR3, A2B7DR15, A3B7DR15, etc) in comparison to the rest of the group. Outcome studies will answer the question whether these disparities are associated with a higher rate of immunological complications seen with URD-BMT.

Recent evidence suggests a more significant role of HLA-C as a target of alloreactions after bone marrow transplantation than previously suspected. Although linkage disequilibrium (LD) between HLA-B and -C serogroups is well documented, the level of LD at the allelic level is not known. In this study, we determine the LD between HLA-B and -C alleles and estimate the probability of molecular HLA-C matching between unrelated individuals who match for both HLA-B alleles.

The genetic polymorphism of the vitamin B12 transport protein transcobalamin II (TC II) was studied in a Caucasian population and in families. There are five codominent alleles of TC II which show a Mendelian mode of inheritance. No genetic linkage of TC II was found with gene loci for ADA, GLOI, Pi, HLA, AB0 and AK1. TC II like proteints could be detected on autoradiograph of PAGE in two patients with congenital homozygosity for functional TC II deficiency. These vitamin B12 binding proteins in the patients' serum were shown not to be normal R-proteins.

Chronic myelogenous leukemia (CML) cells are characterized by a t(9;22) translocation, which can encode one of two chimeric P210 bcr-abl fusion proteins, comprising products of either the b2a2 or the b3a2 exon junction. The junctional sequences represent potentially immunogenic tumor-specific antigens. Despite their intracellular location, the fusion proteins might be recognized immunologically by T lymphocytes if peptides, derived from these unique sequences, are capable of presentation by the major histocompatibility complex molecules. We previously found that four peptides, 9 to 11 amino acids long, spanning the b3a2 CML breakpoint bind with high or intermediate affinity to purified HLA class I molecules A3, A11, B8, or both A3 and A11. We tested the ability of these peptides to elicit specific class I restricted cytotoxic T lymphocytes (CTLs) in vitro in HLA-matched healthy donors. In addition, a longer b3a2 CML-breakpoint–derived peptide, 25 aminoacids in length (b3a2-25), was studied for its ability to induce peptide-specific, class ll-mediated, T-cell proliferation. In four of four HLA-A3 donors tested, CML-A3/A11 -peptide specific CTLs were induced that killed an allogeneic HLA-A3–matched peptide pulsed leukemia cell line. In two of three HLA-A3 donors, the CML-A3/A11 peptide was able to induce killing of autologous and allogeneic HLA-matched peptide-pulsed peripheral blood mononuclear cells (PBMC). CML-A3 peptide induced peptide specific CTLs in one of the four HLA A3 donors tested. No killing was observed in two HLA-B8 and two HLA-A11 donors. PBMC from seven donors were also tested for anti b3a2-25 peptide proliferation in a thymidine incorporation assay. Specific proliferation was detected in three donors, all of the HLA-DR11 haplotype. These data represent the first evidence of a cytolytic human immune response against CML bcr-abl oncogene–derived peptides and provide a rationale for developing peptide-based vaccines for this disease.

Risk factors for graft failure were analyzed in 122 recipients of an allogeneic T-cell-depleted human leukocyte antigen (HLA)-identical sibling marrow transplant as treatment for leukemia. In each case pretransplant immunosuppression included 1,375 to 1,500 cGy hyperfractionated total body irradiation and cyclophosphamide (60 mg/kg/d × 2). No patient received immunosuppression posttransplant for graft-versus-host disease (GVHD) prophylaxis. Nineteen patients in this group experienced graft failure. The major factors associated with graft failure were transplants from male donors and the age of the patient (or donor). Among male recipients of male donor derived grafts a low dose per kilogram of nucleated cells, progenitor cells (colony forming unit-GM) and T cells was also associated with graft failure. Additional irradiation to 1,500 cGy, high dose corticosteroids posttransplant, and additional peripheral blood donor T cells did not decrease the incidence of graft failure. In addition, type of leukemia, time from diagnosis to transplant, an intact spleen, or the presence of antidonor leukocyte antibodies did not correlate with graft failure. To ensure engraftment of secondary transplants, further immunosuppression was necessary but was poorly tolerated. However, engraftment and survival could be achieved with an immunosuppressive regimen in which antithymocyte globulin and high dose methylprednisolone were administered both before and after infusions of secondary partially T-cell-depleted marrow grafts.

Abstract:  The protein-coding sequences of the major histocompatibility complex (MHC) genes are characterized by extraordinarily high polymorphism, apparently maintained by balancing selection, which favors diversity in the peptide-binding domains of the MHC glycoproteins. Here we report that the introns flanking the polymorphic exons of the human MHC class I loci HLA-A, -B, and -C genes have been relatively conserved and have become locus-specific apparently as a result of recombination and subsequent genetic drift, leading to homogenization within loci over evolutionary time. Thus, HLA class I genes have been shaped by contrasting evolutionary forces maintaining polymorphism in the exons and leading to conservation in the introns. This study provides the first extensive analysis of the introns of a highly polymorphic gene family.

R-type vitamin B12binding proteins (R proteins) from human granulocytes, erythrocytes, plasma, and other body fluids were characterized by isoprotein banding patterns on autoradiograms after resolution via thin-layer Polyacrylamide isoelectric focusing (IEF) gel electrophoresis. R proteins obtained from various tissue sources in a given individual show tissue-specific electrophoretic patterns. The desialated R proteins obtained following in vitro treatment with neuraminidase are. however, the same for any given individual and do not show tissue specificity. The differences seen in native R proteins (i.e., transcobalamin I, III, and others) obtained from different tissues are due to variations only in the sialic acid content. Granulocytes from patients with chronic myelogenous leukemia (CML) contain both TC I and TC III, and these R proteins can be released in vitro by lithium stimulation. Normal granulocytes contain only TC III. Differences in desialated R proteins from individual to individual are due to a genetic polymorphism controlled by a single genetic locus (designated TCR) with two alleles, 1 and 2, which are found to be codominantly expressed in heterozygous individuals. The allelic variants of the desialated R proteins found in different blood cells and body fluids are controlled by only one genetic locus.

Abstract: DNA typing of HLA class I1 alleles of the DRB1/3/4 and DQBI loci using sequence‐specific oligonucleotide probes and polymerase chain reaction‐amplified DNA was used for the large‐scale typing of donors for the National Marrow Donor Program unrelated donor registry. The results of quality control analysis for the first 7 months of the project show the typing to be highly accurate, specific, and reliable. The percent of correctly classified HLA oligotypes based on 1652 DRB1 and 1652 DQBI assignments was greater than 99% for DRBI/DRB3/DRM and greater than 98% for DQBI. This level of accuracy is particularly remarkable because the quality control samples could not be distinguished from 9011 donor samples tested at the same time by the laboratories.

The HLA-C encoded gene products display several characteristics which distinguish them from HLA-A and -B. The HLA-C antigens are poorly expressed on the cell surface, they display multiple proteins with different isoelectric points, and alloimmunization to HLA-C antigens is less common. To investigate whether the multiple products result from differential splicing of HLA-C gene transcripts, we have isolated a full-length cDNA clone encoding the Cw6 antigen. Class I antigens produced by the cDNA clone in transfected cells were of the same relative mass as those observed in the parental cells when analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Isoelectric focusing (IEF) gel analysis of the cDNA translated products in transfectants revealed multiple IEF bands. All IEF bands detected in the transfectants were also found in the parental cells, indicating that the multiplicity of the C-locus products was not due to differential splicing of HLA-C gene transcripts, but was probably due to post-translational modification. Comparison of the sequences of C-locus alleles with those of A and B alleles did not show any apparent sequences which would generate multiple IEF bands. Comparison of the coding regions for seven HLA-C alleles and one HLA-C-related class I gene with available data for 15 HLA-A and 20 HLA-B alleles demonstrated several unique features for the HLA-C locus. Six sites in the extra cellular domains, three in al and three in a3, were unique. While the cytoplasmic (CP) domain of HLA-A and -B are almost identical, the CP of HLA-C alleles is unique. Similar unique features of HLA-C are also observed in the transmembrane domain, resulting in locus-specific residues between positions 295 and 300. The present study has ruled out differential mRNA splicing as a mechanism for the multiplicity of Cw6 antigens and demonstrated unique HLA-C locus sequences.

In a previous report we described how cross-immunizations of pairs of transgenic mice expressing different HLA class I antigens led to the production of antibodies directed exclusively at polymorphic epitopes. This was ascribed to self-tolerance of HLA that prevents immune responses to monomorphic epitopes and focuses responses on polymorphic ones. In the present report we extend our findings and demonstrate that immunizations of class I transgenic mice with HLA transfected mouse fibrosarcoma as well as with human lymphoblastoid cells also preferentially yield antibodies to polymorphic epitopes. This was the case whether or not immunizations were carried out across locus barriers [e.g., Tg (HLA-A *0201) or Tg (HLA-Cw*0301) transgenic mice immunized with HLA-B27 transfectants] or within the same locus [e.g., Tg (HLA-B*1302) transgenic mice immunized with HLA-B27 transfectants or B27-expressing lympho-blastoid cell]. Use of an extended immunization protocol with four or more booster injections favored antibodies of IgG isotype with affinities high enough to lyse normal peripheral blood lymphocytes (PBLs) in complement-dependent cytotoxicity assays and to immunoprecipitate HLA antigens. The specificities covered by the monoclonal antibodies (mAbs) could be either broad or narrow, depending on the genetic distance of the HLA antigens or alleles involved. For instance, a Tg(HLA-B*1302) transgenic mouse immunized with B27 produced both broad B7/B27-specific antibodies, Bw4-specific antibodies, and one antibody reacting with all B alleles except B13 and with some C alleles. On the other hand, a Tg(HLA-B*1302) transgenic mouse immunized with Bw47 transfectants responded narrowly with an antibody to Bw60 and Bw47. Thus it appears that by choosing appropriate recipient mice and closely related or more distant HLA antigens, antibodies of a programmed specificity can be generated.

HLA-B 13 antigens were isolated from metabolically labeled cell extracts from Caucasian and Oriental donors by means of an HLA-B13-specific monoclonal antibody, SY1. Ethnic differences in B13 molecules were identified by one-dimensional isoelectric focusing in which the pI of desialated Oriental B13 molecules was found to be higher than that of Caucasians. An additional Caucasian variant pattern was detected by peptide mapping using limited proteolysis in sodium dodecyl sulfate analyzed by polyacrylamide gel electrophoresis. Dual allotypic determinants for B13 molecules were recognized by two HLA-B13-specific monoclonal antibodies, SY1 and TU110, as determined by their sensitivity to complement-dependent cell lysis. Whereas the SY1 target epitope was shared by both ethnic B13 molecules, the two ethnic B13 molecules carried different Tu110 target structures. The Caucasian variant molecules appear to carry altered allotypic determinants which are recognized by both SY1 and Tu110 antibodies. This study suggests that the HLA-1313 private structure may comprise two epitopes recognized by SY1 and Tü 110 antibodies, respectively, whose binding sites overlap. Present data also suggest that the private determinant was already present when the two racial groups diverged, and thus the mutations which gave rise to the variants may be of relatively recent origin.

A new mouse monoclonal antibody (MoAb) 4E, which detects an epitope shared by HLA-B locus antigens, together with the MoAb W6/32, detecting a common HLA, B, C, determinant, and the MoAb 4B, detecting HLA-A2 and A28, were used to isolate HLA-A and -B antigens in sequential immunoprecipitation. The HLA antigens obtained from metabolically labeled cell extracts of B-lymphoblastoid cell lines or from phytohemagglutinin (PHA) activated peripheral blood lymphocytes were compared by one-dimensional isoelectric focusing (1D-IEF). The IEF banding patterns obtained with native HLA antigens segregated in a family with HLA. Neuraminidase treatment of isolated antigens reduced the number of bands to one or two, simplifying the analysis of characteristic patterns. Thus, we have cataloged IEF banding patterns for the majority of the serologically recognized HLA-A and -B allotypes obtained from 57 unrelated American Caucasians. While no HLA-A locus or HLA-B locus specific banding patterns were observed, the HLA-A antigens had, in general, slightly higher pl values than the HLA-B antigens. HLA-C antigens could not be detected in this assay system. The polymorphism detected by IEF banding patterns was as extensive as the serologically detected polymorphism identified by classical HLA serology. Moreover, variants for some HLA allotypes could be detected by this method. In addition to previously recognized A2 variants, new variants were identified for HLA-A1, A26, and Bw44. Each A1 and Bw44 variant was associated with particular haplotypes. The HLA-A2 antigens occurred on 43 HLA haplotypes in the unrelated Caucasian population. Only one of each A2 variants was identified in this population.

THE HLA complex consists of many closely linked genes which code for a variety of characters, particularly the expression of cell surface antigens found on lymphocytes (HLA-A, B, C, DR antigens) or erythrocytes (Chido and Rodgers blood groups) and polymorphic variation of certain complement components (Bf, C2, C4). We1have recently suggested that the polymorphism of the fourth component of human complement (C4), detected by immunofixation electrophoresis, is controlled by two genes linked to HLA and not by codominant alleles at a single locus as previously described2,3. One C4 variant, designated F, is controlled by one locus with alleles determining the presence (F+) or absence (f0) of four fast-moving anodal bands of C4 while the second variant, S, is controlled by a second locus with alleles determining the presence (S+) or absence (s0) of four slow-moving cathodal bands. We noted that C4 F individuals homozygous for the s0allele and lacking the four cathodal bands were always Chido (Cha) negative, whereas individuals homozygous for the f0allele and lacking the four anodal bands of C4 (C4 S) were always Rodgers (Rga) negative. This intriguing observation led us to study the relationship of Chido and Rodgers red cell antigens, which are also found in serum and C4. We show here that Chido and Rodgers are distinct antigenic components of human C4, a finding which provides a biological explanation as to why these unique red cell antigens are controlled by genes of the HLA complex.

Estimation of the National Marrow Donor Program's Be The Match Registry (BTMR) 8/8 (HLA-A, B, C, DRB1) high resolution (HR) unrelated donor (URD) match rate was determined in a 2009 study for each of the four most frequent patient race/ethnic groups in the United States- Caucasian (CAU), African American (AFA), Hispanic (HIS), and Asian Pacific Islander (API) (Dehn et al, ASBMT/CIBMTR abstract 2011). For patients without an 8/8 matched URD, a 7/8 match is often the minimum acceptable mismatch used by many transplant centers. A follow up to the 8/8 study was designed to determine the 7/8 or better match rate among the 4 major race/ethnic groups, using the same study cohort.1344 previously high resolution tested URD in the BTMR were randomly selected and treated as pseudopatients (PP) where HR testing was performed to identify an 8/8 matched URD. Following 8/8 potential URD testing, a search was performed on each PP to determine the 7/8 match rate, regardless of whether an 8/8 match was previously identified. The searches used a fixed BTMR file from January of 2012, composed of over 8.6 million URD. The BTMR race/ethnic diversity breakdown for 2012 was 65% CAU, 7% AFA, 10% HIS, 7% API, and 11% miscellaneous categories such as Multiple, Unknown, American Indian- Alaska Native, and Declined to answer. Search results from CAU (N=377), AFA (N=390), HIS (N=307), and API (N=270) PP were evaluated and classified as follow:1) 7/8 HR matched donor exists on BTMR2) Potential 7/8 HR donors exist on BTMR3) No 7/8 potential donors exist on BTMRPP searches falling into category 2 had an HLA search strategy expert rank potential URD within BTMR in order of their matching likelihood. URD samples were HR HLA tested in order of ranking and evaluated to determine match status. Consecutive rounds of URD sample testing were performed until either a 7/8 matched URD was identified, no potential URD with stored samples remained, or a patient maximum number of URD testing was reached.Since many PP searches had greater than 100 potential 7/8 matched URD, it was not possible to type every URD. In these cases, up to 35 URD with sample were tested per patient. For analysis of the 7/8 match rate, PP with no 7/8 match identified after URD testing were considered as having no HR match.98% of CAU and over 80% of the non-CAU race/ethnic groups- AFA, HIS, and API- had at least a 7/8 match identified (Table 1). For cases where an 8/8 matched donor had been previously identified, all but 8 PP also had a 7/8 match (CAU= 1, AFA= 3, API= 3, HIS= 1). Only three PP cases had no 7/8 potential donors on the search prior to URD testing. The range of donors tested for the cases resulting in a match was larger for the non-CAU race groups. The maximum number of URD tested before a 7/8 match was identified was 24 for AFA, 6 for HIS, and 10 for API, while for CAU the maximum number of URD tested was 2 (Table 2). A median of 1 URD was typed for cases resulting in a 7/8 match for each of the four race/ethnic groups. HLA expert review of cases where no 7/8 match was identified but additional 7/8 potential URD remained suggests that few additional cases would likely yield HR matches.This study estimates a 7/8 or better HR match rate for the BTMR of over 80% for all four broad race/ethnic group categories. These results show that in the majority of cases, after first testing to identify an 8/8 matched URD, a 7/8 matched URD was identified after typing just one URD. However, particularly with non-CAU patients, testing additional URD may be needed to identify a 7/8 match. This study provides a baseline match rate that can be further supplemented using the additional worldwide URD inventory.No relevant conflicts of interest to declare.

To better plan recruitment of volunteer adult unrelated donors for a registry and umbilical cord blood donations for cord banks to supply grafts for hematopoietic cell transplantation to serve Indian transplant candidate patients, we analyzed existing HLA typing data to estimate Indian national and regional populations' HLA haplotype frequencies.

Estimation of the National Marrow Donor Program's Be The Match Registry (BTMR) 8/8 (HLA-A, B, C, DRB1) high resolution (HR) unrelated donor (URD) match rate was determined in a 2009 study for each of the four most frequent patient race/ethnic groups in the United States- Caucasian (CAU), African American (AFA), Hispanic (HIS), and Asian Pacific Islander (API) (Dehn et al, ASBMT/CIBMTR abstract 2011). For patients without an 8/8 matched URD, a 7/8 match is often the minimum acceptable mismatch used by many transplant centers. A follow up to the 8/8 study was designed to determine the 7/8 or better match rate among the 4 major race/ethnic groups, using the same study cohort.

Joshi: Manipal Hospital, Bangalore: Employment. Damodar:NARAYAN HRUDAYALAYA: Employment. Cereb:Histogenetics: Employment. Young Yang:Histogenetics: Employment. Dedhia:Marrow Donor Registry (India): Employment.