DR typing in Australian Aborigines. An indication for a second locus in the HLA--D region defined by serology

Heterogeneity in HLA-DR2-related DR,DQ haplotypes in eight populations of Asia-Oceania

The relative distributions of 480 DR2-related DR,DQ haplotypes have been determined in Australian Aborigines, Papua New Guinean Highlanders, coastal Melanesians, Micronesians, Polynesians, Javanese, and Southern and Northern Chinese. Using sequence-specific oligonucleotides (SSOs) for hybridization of polymerase chain reaction (PCR) products from DRB1, DRB5, DQA1, and DQB1 genes, 15 different DR2-related haplotypes were identified. The predominant DR2 haplotype in Oceania involved a novel combination of DRB1*1502, DRB5*0101 alleles; this haplotype occurred sporadically in Java, but not in China. In Southern China, the most frequent DR2 haplotype involved the unusual arrangement DRB1*1602,DRB5*0101; alternatively, DRB1*1602 was associated with a new DRB5 SSO pattern. This study has important implications for molecular HLA-typing protocols that assume particular DRB1, DRB5 or DR,DQ linkage relationships. Further, the novel DRB1, DRB5 haplotype in Oceania suggests that the mixed lymphocyte culture (MLC) determinants Dw2 and Dw12 are discriminated by codon 86 at the DRB1 locus.

High risk of squamous cell carcinoma of the cervix for women with HLA-DQw3

Many immune responses are controlled by genes of the major histocompatibility complex (MHC). In man these include the loci encoding the HLA-A, -B, -C, -DR, -DQ and -DP antigens, and many diseases have been linked with these. But attempts to identify HLA genes in man that might explain why an immune response against malignant tumours should be ineffective have so far been disappointing, apart from the association reported between the HLA-DR1 antigen and a susceptibility to a rare carcinoma of the thyroid gland. Here we describe another strong connection between a common malignant tumour and an HLA antigen, namely between HLA-DQw3 and squamous cell carcinoma of the cervix: from the 1988 United States tumour registry, 1 in every 63 newborn girls will develop this invasive cancer. We found that 88% of 66 patients had the leukocyte antigen HLA-DQw3 when it would normally be expected in only 50% of individuals. In animals the immune system and the MHC act in defence against virally induced tumours, but until now there has been no evidence that they do so in humans: as squamous cell carcinoma is probably virally induced, our discovery of its association with an HLA antigen will be important to the understanding of the immunogenetic basis of a susceptibility to this tumour.

HLA-DR RFLP distributions in two groups of aboriginal Australians

HLA-DR and -DQ typing by restriction fragment length polymorphism (RFLP) in Aboriginal Australians from the Kimberleys and from Coen shows a restricted number of HLA-DR types in these populations. The polymorphism is essentially limited to DR2, DR4, DRw14 and DRw8. The most common DR.DQ RFLP haplotype in Aborigines shows a novel arrangement of DR and DQ alleles that has important implications for histocompatibility matching if the RFLP patterns reflect functional variation in HLA class II molecules.

HLA-DR and -DQ DNA genotyping in seven populations of Asia-Oceania and Australia

Haplotype patterns of HLA-DR and -DQ restriction fragment length polymorphisms (RFLPs) were compared in seven populations in the region of Asia-Oceania: Australian Caucasoids, Melanesians, micronesians, Polynesians, Chinese, Koreans, and Japanese. Several DR beta RFLP patterns, including those correlating with DR2, 4,5, w6, 7 and w8 in Caucasoids, were associated with multiple DQ alpha/DQ beta RFLP haplotypes, of which only two occurred universally - one associated with DR4 and one with DR5. RFLPs revealed new population or group specific characteristics, which had not been previously discovered using serological or cellular HLA typing techniques. The populations of Asia-Oceania have some features of the class II RFLPs in common, which are distinctly different from Caucasoids. On the other hand, a number of characteristics distinguish between the various Asian and Pacific groups. This study demonstrates the power of RFLP analysis of closely linked genes in population genetics, and shows the value of ethnic comparisons in further characterizing the polymorphisms of the HLA class II genes.

Molecular characterization of three HLA class II molecules on DR4 and DRw9 haplotypes: serologic and structural relationships at the polypeptides level

By using alloantisera, three distinct HLA-D/DR region-encoded class II molecules were identified from cells carrying the HLA-DR4 and DRw9 haplotypes. Both DRw-53 and DQw3 molecules that bear the "supertypic" specificity were isolated independently from the DR antigen. The light chains of the DR4 antigens from different HLA-D types were distinct from one another, whereas the DRw53 molecules had identical charge and molecular weight in both heavy and light chains. On the other hand, the DQw3 molecules from the DR4 cell lines (Dw4 and Dw 10) were apparently identical but were polymorphic at least in the light chains among the DR4, DR5, and DRw9 haplotypes. In addition, monoclonal antibodies which specifically precipitate DR4 and DQw3 molecules have been isolated. The variable extent of homogeneity and diversity of three class II molecules may aid in our understanding of the role of class II antigens in the human immune regulation.

The molecular specificities of DS-specific reagents: an MB3-like monoclonal antibody isolates two DS molecules

HLA-DS molecules are the human homologues of murine I-A molecules. The molecular specificities of four anti-DS reagents were examined by two-dimensional gel electrophoresis in light of the recent evidence that HLA-DR homozygous cell lines express at least two DS molecules. Each of the DS-specific reagents, including the IVD12 monoclonal antibody which defines an MB3-like determinant, isolated at least two DS molecules from a DR5 homozygous cell line. Because previous studies of this cell line documented that anti-MB3 allosera isolated only one DS molecule, these data indicate that there is heterogeneity of the molecular specificities of anti-Ia reagents that are specific for the MB3 allodeterminant or the MB3-like determinant in population studies.

Immunochemical analysis of class II molecules expressed by a human B cell line with the unusual class II genotype, DR5+, MB1+, (MB3-), MT2+

The human B lymphoblastoid cell line FPA was established from a consanguineous individual homozygous for the unusual serologically defined Class II genotype, DR5+, MB1+, (MB3-), MT2+. The MB1 allodeterminant is classically found only in association with DR1, 2, or w6 and DR5 is almost invariably associated with MB3. Class II molecules expressed by this unusual DR5 homozygous cell line have been characterized by immunochemical analysis using two-dimensional gel electrophoresis. These molecules were isolated from the FPA cell line by anti-DR5, anti-MT2, and anti-MB1 allosera, as well as a monoclonal antibody which defines an MB1-like determinant. However, an anti-MB3 alloserum and a monoclonal antibody which defines an MB3-like determinant did not immunoprecipitate Class II molecules from FPA. These studies document that the MB1 allodeterminant resides on DS molecules from this DR5 cell line and provide additional evidence that MB1 and MB3 are alleles of the same Class II antigen system.

Different functions and associations of HLA-DR and HLA-DQ(DC) antigens shown by serological, cellular and DNA assays

Two consanguineous Caucasoid HTCs, DHI and FPA, were investigated, the latter having an unusual HLA-DR/DQ(DC) association. Both these HTCs typed clearly as HLA-DRw11. However, while DHI typed as DRw11/DQw3(DC4) as expected, FPA typed as DRw11/DQw1(DC1) instead. Although extremely rare in Caucasoids, DRw11/DQw1 is a common pattern of association in Nigerian Negroids. Southern blots of DNA extracted from EBV cell line derived from FPA, hybridized with HLA-DC alpha and HLA-DC beta probes, confirmed this unusual DRw11/DQw1(DC1) association. In addition the DC alpha probe showed a unique additional restriction fragment length polymorphism (8 kb) attributable to the DX gene in the FPA DNA. When DHI and FPA were used as stimulators in MLC, the patterns to typing responses obtained were not completely concordant although they overlap to some extent. For this reason FPA has been locally designated Dw'F5', distinct from Dw5. Furthermore, the HLA-DQ antigens of the responder cells were not necessarily the same as those of the HTCS to which they gave typing responses (FPA and DHI). Functional studies using these two HTCs showed that the DQ(DC) antigens probably have no direct lymphocyte activating properties but rather have a regulatory role in controlling responses to allodeterminants in MLC.

The complexity of HLA-DS molecules. A homozygous cell line expresses multiple HLA-DS alpha chains

Ia molecules expressed by an HLA-DRw6 homozygous cell line were immunoprecipitated with anti-Ia allosera and monoclonal antibodies and analyzed by 2-D gel electrophoresis. The DRw6 homozygous cell line was shown to express two DS beta chains; this observation extends our previous finding that a DR5 homozygous cell line expresses two DS beta chains and suggests that the expression of at least two DS beta chains by DR homozygous cell lines is a generalized phenomenon. The data presented here document for the first time that a DR homozygous cell line expresses at least two DS alpha chains. Therefore, this cell line expresses at least two DS molecules with the potential for the expression of four DS molecules. In agreement with previous reports, the cell line was shown to express two DR beta chains and one DR alpha chain that combine to form two DR molecules. The molecular specificities of two MB1 allosera and two MB1 -like monoclonal antibodies were also compared in these studies. Both MB1 allosera isolated a single DS molecule, while the MB1 -like monoclonal antibodies isolated at least two DS molecules. Therefore, these studies document for the first time that anti-Ia reagents which are specific for the MB1 or MB1 -like determinants in population studies do not recognize the same Ia molecules in immunochemical studies. The data presented here for the expression of at least two DS alpha chains and the location of the MB1 allodeterminant on only one of multiple DS molecules are in agreement with recent studies at the gene level.

Identification of three class II antigens, DR7, MB2, and MT3, from a homozygous human cell line

The class II antigens from a homozygous DR7 human B cell line were isolated by immunoprecipitation with human alloantisera or monoclonal antibodies. Three class II light chains and three class II heavy chains were identified. The heavy and light chain subunits of the DR7 antigen were distinct from those of the MB2 antigen as assessed by two-dimensional gel electrophoresis. A third light chain in addition to the DR7 and MB2 subunits was precipitated by some alloantisera containing MT3 antibodies. The monoclonal antibodies examined immunoprecipitated one or more of the three class II antigens. The MB2 antigen appeared to be the same as the major antigen recognized by L227 and the DS7 antigen precipitated by SG171.

HLA polymorphisms in a Shanghai Chinese population

The frequencies of the HLA-A, B, C, D, DR and MB antigens have been determined in a homogeneous Shanghai Chinese population. Comparisons with the HLA-A and -B frequencies in other subsets of the Chinese population revealed some marked differences. No comparisons were possible for the D, DR and MB antigens since there were no previous studies of the antigens in those loci. We suggest that studies of the Chinese population should be confined to clearly defined homogeneous subsets. In this manner, the confounding effect of population heterogeneity may be avoided, and it is this heterogeneity which calls for extensive surveys of the huge Chinese population.

Expression of T-lymphoblast-encoded HLA-DR, MT, and SB antigens on human T-B lymphoblast hybrids

The Ia-like antigens of hybrids of the B-lymphoblastoid cell line (B-LCL) WI-L2 and a subline of the T-lymphoblastoid cell line (T-LCL) HSB were examined. Antigens of the HLA-DR and MT series were analyzed by indirect immunofluorescence with chimpanzee anti-DR sera and monoclonal antibodies, and antigens of the SB series were analyzed by primed lymphocyte typing (PLT). The WI-L2 X HSB hybrids expressed antigens of each series not found on either parent cell. In each case, the novel antigens were indistinguishable from those found on SB, a B-LCL established from the same individual as HSB, and are thus presumably HSB encoded.

Differential expression of HLA-DR and DR-linked determinants on human leukemias and lymphoid cells

Leukemic and normal hemopoietic cells were examined with the monoclonal anti-bodies DA2 and Genox 353 for the presence of HLA-DR and DR-linked (DC/MB) determinants, respectively. Although most non-T acute leukemias and leukemic cell lines expressed the monomorphic DR determinant detected by DA2, fewer than expected expressed the DR-linked polymorphic specificity detected by Genox 353. TdT+ lymphoid precursors from normal bone marrow were also DA2+ but Genox 353-. T cells and thymocytes which were DA2-, Genox 353- became DA2+, Genox 353+ after activation in vitro. Immunoprecipitation using DA2 and Genox 353 gave bands on polyacrylamide gel-electrophoresis which were of different molecular weights. In addition, DA2 could absorb out Genox 353 determinants from a cell lysate whereas Genox 353 could not absorb out DA2 determinants. It is concluded that DA2 and Genox 353 detect HLA-DR and DR-linked (DC1/MB1) determinants, respectively, and that these are differentially expressed on hemopoietic cells during differentiation.

Reanalysis of the HLA-DRw6 complex

The serological definition of the HLA-DRw6 specificity has been complicated by the lack of monospecific reagents. During the 8th International Histocompatibility Workshop several subspecificities of DRw6 were proposed. In the present study we have reanalysed the reactions of 8th Workshop and local sera in families and homozygous typing cells. These studies have revealed four DRw6 related reaction patterns. The patterns are described and compared with those reported by others. Two of these specificities are commonly observed in Dutch Caucasoids, one related with Dw6 and one with Dw9. The other DRw6 related reaction patterns are very infrequent in this population. In addition, the relation between a locally defined specificity LB5x8 and two new specificities 8wDRw13 and 8wDRw17 is discussed.

Identification of a human Ia antigen that is different from HLA-DR and DC antigens

A monoclonal antibody, MHM4, identified a cell surface antigen present on B cells and not resting T cells. It precipitated two polypeptide chains of 34 000 and 28 000 daltons from B lymphoblastoid cells. This antibody bound to all B-cell lines tested, except those homozygous for HLA-DR7. Saturation binding assays and Scatchard plots of MHM4 binding to cells that did not carry HLA-DR7 indicated that this antibody bound less than the total surface Ia antigen. When the antibody was competed with eight other HLA-D-specific antibodies, the epitope recognized was shown to be distinct. Two-dimensional gel analysis revealed that a simple pattern of spots was precipitated, unlike the complex patterns obtained with other HLA-D-specific antibodies. The alpha and beta spots were different from those precipitated by HLA-DR- or DC-specific antibodies. It is argued that the MHM4 antigen is the product of an HLA locus that is distinct from HLA-DR and DC. Its relationship with HLA-SB is discussed.

A monoclonal antibody recognizing HLA-DR2 on malignant and activated cells

A monoclonal antibody, designated NDS15.38, which recognizes a polymorphic determinant of HLA-DR, was produced from a fusion in which mice were immunized with the human B lymphoblastoid cell line GIR2 (HLA type A1, B8, 27, Cw2, DR2,7). NDS15.38 functions efficiently as an affinity column and purifies a two-chain complex of molecular weight 33 000 and 30 000 under reducing conditions. The monoclonal antibody reacts with HLA-DR2-positive B lymphoblastoid cell lines and B lymphocytes from patients with chronic lymphatic leukemia in an indirect radioactive binding assay. However, NDS15.38 does not appear to react with peripheral blood B lymphocytes from normal individuals. Using a peroxidase staining technique, NDS15.38 was shown to react with phytohemagglutin (PHA)-stimulated lymphocytes and with apparently activated B cells in the germinal centers of lymph nodes from individuals who were tissue typed as HLA-DR2. Thus it appears that NDS15.38 recognizes a polymorphic determinant of HLA-DR on malignant and stimulated cells, but not on resting cells.

Structural polymorphism of the DC1 light chains from DR1-, DR2-, and DRw6-positive cell lines

The heavy and light chain subunits of the DC1 antigen from several cell lines expressing different DR specificities were compared by two-dimensional (2-D) gel electrophoresis. The DC1 light chains from cell lines typed as DR1, DR2, or DRw6 differed in their isoelectric points. No difference in charge was observed for the DC1 heavy chain from the three cell lines. The DC1 light chains from different DRw6-positive cell lines were also found to be structurally polymorphic. The DRw6 cell lines examined did not all express the same DR-like light chains, indicating that the DRw6 specificity is biochemically complex, which is in agreement with the serologic studies of others.

HLA antigens in Bali (Indonesia) with a special reference to an isolated community

One hundred eighty-two Balinese were typed for HLA-A and -B locus antigens. From these, 103 were also typed for HLA-C, 51 for HLA-DR, 172 for Bf and 173 for GLO. These results and the significant phenotypic associations are situated with respect to other South-East Asian populations. In addition to this first study, 175 individuals from an isolated Balinese village typed for HLA-A, -B, -DR, Bf and GLO are presented. The effect of isolation on haplotype (HLA-A/-B/Bf/-DR) variability is discussed.

Cell membrane polymorphisms coded for in the HLA-D/DR region. I. Relation between D and DR

The relation of HLA-D and -DR determinants was studied in Dutch Caucasoids. The recognition of subgroups of DR4, DR5, and DR7, and the specificities LB12 and LB13 are described. Phenotype and gene frequencies and a Hardy--Weinberg analysis of DR and local (LB) B-cell groups are given. Excellent correlation between D and DR typing was obtained when HTCs were studied by selected B-cell antisera. When the same sera were used to type a panel of D typed cells, the correlation was decreased (with the exception of DR3 and Dw3). In the case of discrepancies the DR specificity, but not the corresponding D specificity, always could be found and not the other way around. The data fit best the assumption that HLA-D and -DR are carried by the same molecule, although they might be different determinants on this molecule. A number of possible explanations for the observed discrepancies has been given.

HLA-D-DR relationships: PLT studies of HLA-D specificities associated with DR1, DR2, and DR4

The primed lymphocyte test (PLT) detects gene products of the HLA-D-DR region which activate the secondary (memory) response of MLC stimulated T cells. In the present study attempts were made to determine whether different HLA-D alleles associated with the same DR, such as DR1, 2, and 4 can be discriminated by PLT typing. PLTs were generated by using, as responders and primary MLC stimulators, HLA-D different HTCs which shared all DR groups (major DR, supertypic MT and second locus MB) or only the MT or MB groups. As secondary stimulators, lymphocytes from an HLA-D selected panel of 72 individuals were used. PLTs raised in DR identical responder-primary stimulator combinations were able to discriminate between the different HLA-D antigens associated with the same DR. In contrast, when priming was performed in combinations differing for the major DR group, the restimulation response was highly associated with the DR specificity of the primary stimulator, regardless of whether or not this was compatible with the responding HTC for the MT or MB groups. This data indicate that the specificity of primed lymphocytes largely depends on the combinations used for priming and that the memory response can be activated by both HLA-D and DR antigens. The dissociation of HLA-D from DR by PLT typing might provide a useful tool for further analysis of this HLA region.

Human B-cell alloantigens DC1, MT1, and LB12 are identical to each other but distinct from the HLA-DR antigen

Some human B-lymphoblastoid cell lines are shown to express at least two types of Ia-like antigens. One antigen is defined by alloantisera to HLA-DR, and the other antigen is defined by alloantisera and a monoclonal antibody to the specificities DC1, MT1 (MB1), and LB12, which are in linkage disequilibrium with HLA-DR. The subunits of the DC1 molecule differ from those of the DR molecule. The light chains of both molecules are structurally polymorphic.