Complete sequence of an HLA-dR beta chain deduced from a cDNA clone and identification of multiple non-allelic DR beta chain genes

Sequencing and genetic analysis of a bovine DQB cDNA clone

A BoLA-DQB cDNA clone (BoLA-DQ beta-1) was isolated by screening a bovine lymphoblastoid cDNA library with a HLA-DQB genomic clone. The DNA and predicted protein sequences were compared to class II sequences from cattle and other species. BoLA-DQ beta-1 has 92.0% similarity to the coding regions of two previously sequenced BoLA-DQB genomic clones and 69.6% similarity to a BoLA-DR beta pseudogene. However, the first domain encoded by BoLA-DQ beta-1 has 94 amino acids; one more than the predicted size of the products encoded by two previously sequenced bovine DQB genes (BoDQ beta-Q1 and BoDQ beta-Y1). Comparing all coding regions, BoLA-DQ beta-1 has greater nucleotide similarity to HLA-DQB sequences than to I-A beta, HLA-DRB and I-E beta sequences. Like the HLA-DQB gene product, the cytoplasmic domain of the predicted protein encoded by BoLA-DQ beta-1 is eight amino acids shorter than that of I-A beta, HLA-DRB and I-E beta molecules. Six clone-specific amino acid substitutions were identified in the beta 1 domain of BoLA-DQ beta-1, including an unusual cysteine residue at position 13 which is believed to be positioned on a beta-strand and face into the antigen recognition site. Southern blot analysis of PvuII-digested genomic DNA from a paternal half-sibling family (sire, and six dam-offspring pairs) using BoLA-DQ beta-1 as a probe, revealed five allelic PvuII RFLP patterns, including two patterns not previously described, that cosegregated with serologically-defined BoLA-A (class I) alleles. The evolution, polymorphism and function of a transcriptionally active BoLA-DQB gene can now be readily studied using this DQB cDNA clone as a source of allele and locus-specific oligonucleotide primers.

Identification of genetic variation in the bovine major histocompatibility complex DR beta-like genes using sequenced bovine genomic probes

Two bovine genomic clones that crosshybridize with HLA-DR beta cDNA have been isolated. Nucleotide sequence analysis of the beta 1, beta 2 and transmembrane (TM) exon regions for one of these clones revealed 70, 89 and 86% identity with the corresponding HLA-DR beta exons. Stop codons are present in the beta 1 and TM exons and a single base deletion toward the 3' end of the TM exon negates the consensus sequence for exon/intron splicing. Therefore, we conclude this is a bovine DR beta-like pseudogene, BoDR beta I. Exon-containing regions have been used as probes in Southern blot analyses of bovine genomic DNA digested with EcoRI. The beta 2 exon of BoDR beta I results in prominent bands of 18.9, 7.8, 7.2, 6.4, 5.6, 3.6, 3.0 and 2.7 kb. Polymorphisms were observed for all but the 18.9 kb band and at least three of these bands were identified in each of the 185 animals sampled. A probe containing the TM exon of BoDR beta I hybridizes only to the 5.6- and 3.6-kb bands, suggesting that these are allelic bands corresponding to this pseudogene. Results from hybridizations of a TM exon-containing probe of the second bovine DR beta-like clone (BoDR beta II) suggest that the 6.4- and 2.7-kb bands correspond to this second bovine gene. A nonpolymorphic 8.1-kb band results from a probe containing the BoDR beta I beta 1 exon. Major differences in frequency for the 6.4/2.7 alleles were found for the four breeds sampled.

Nucleotide sequence and northern analysis of a bovine major histocompatibility class II DR beta-like cDNA

A 1.2-kb bovine DR beta-like cDNA clone (BoLA-DRB3) was isolated from a peripheral blood lymphocyte cDNA library utilizing a human DR beta cDNA as a probe. BoLA-DRB3 was found to have a high degree of nucleotide sequence similarity (96.8%) with a previously sequenced bovine DR beta-like gene (A1). It is believed that BoLA-DRB3 and A1 represent distinct alleles of one of the three bovine DR beta-like loci. Sequence comparison of BoLA-DRB3 with genes representing the other two bovine DR beta-like loci resulted in moderate degrees of sequence similarities (83.1% and 86.3%, respectively). Comparison of the relative abundance of RNA transcripts of the three bovine DR beta-like loci by Northern analysis of lymphocyte RNA indicated that BoLA-DRB3 is the most actively transcribed of the three bovine DR beta-like genes. Based on these results we suggest that of the three DR beta-like loci thus far identified in the bovine, only one is actively transcribed.

Partial nucleotide sequence of a bovine major histocompatibility class II DR beta-like gene

A genomic clone containing a bovine DR beta-like gene, BoDR beta II, was isolated from a bovine genomic library and characterized by restriction enzyme mapping and nucleotide sequencing of exon regions. Alignment of this sequence with the human DR beta cDNA sequence allowed identification of exon/intron boundaries. The clone contains a 13.3-kilobase (kb) insert, and includes 1.3 kb 5' of the beta 1 exon and 6.7 kb 3' of the transmembrane (TM) exon. Open reading frames were present in the BoDR beta exons sequenced. Nucleotide identities of the bovine beta 1, beta 2 and TM exons with the corresponding human DR beta exons were 73, 91 and 83%, respectively. Nucleotide identities of these exons with those of a previously described bovine DR beta-like pseudogene, BoDR beta I, were 69, 95 and 81%, respectively. Although a limited amount of sequence data was obtained for the intron regions, a 71% identity was found within a 514-nucleotide region immediately 3' to the beta 2 exons in BoDR beta I and BoDR beta II. A series of GT residues followed by a longer series of GA residues began about 35 nucleotides 3' of the beta 1 exon in both BoDR beta I and BoDR beta II.

Restriction fragment length polymorphisms of horse class II MHC genes observed using various human alpha- and beta-chain cDNA probes

Genomic DNA isolated from 20 horses was digested with up to six restriction endonucleases and subjected to southern blot hybridization analysis using various human class II alpha- and beta-chain cDNA probes. A high degree of restriction fragment length polymorphism (RFLP) was found for the DQ alpha, DP beta, DQ beta and DR beta probes, about 20 polymorphic bands being detected for each. DR alpha showed 2-4 polymorphic bands, whereas no evidence for DP alpha-like genes was found. A number of correlations of RFLPs with individual alloantisera were apparent.

Identification by sequencing based typing and complete coding region analysis of three new HLA class II alleles: DRB3*0210, DRB3*0211 and DQB1*0310

The study of HLA class II polymorphism by direct exon 2 DNA sequencing analysis has been established to be a reliable and accurate high-resolution typing procedure. This approach shows some advantages in relation to previous methods, polymerase chain reaction using sequence-specific oligonucleotides (PCR-SSO) and sequence-specific primers (PCR-SSP), basically due to the capability of analysis for the complete sequenced genomic region, including non-polymorphic motifs. DRB3 and DQB1 sequencing based typing (SBT) in unrelated bone marrow donor searching allowed us to detect three new alleles. The complete coding region sequences were characterised from cDNA. Two new DRB3 alleles, DRB3*0210 and DRB3*0211, were described in two Caucasian bone marrow donors. Both sequences showed single point mutations regarding DRB3*0202, producing amino acid replacements at positions 51 (Asp to Thr) and 67 (Leu to Ile), respectively. These two point mutations can be found in other DRB alleles, and suggest that gene conversion would be involved in the origin of both alleles. A new DQB1 sequence was found in a Spanish patient that showed two nucleotide differences, positions 134 and 141, with regard to its close similar DQB1*03011 allele. Only substitution at position 134 provoked amino acid replacement at residue 45, Glu to Gly. This single amino acid change would be involved in the lack of serologic recognition of this new molecule by DQ7-specific reagents.

Clinical correlates, serum autoantibodies and the role of the major histocompatibility complex in French Canadian and non-French Canadian Caucasians with SLE

OBJECTIVE

To investigate the predisposing role of major histocompatibility complex (MHC) genes to autoantibody production and clinical manifestations comparing French Canadian and Non-French Canadian Caucasians with systemic lupus erythematosus (SLE) METHODS: Ninety-one Caucasian patients with SLE were studied. Clinical manifestations, autoantibody expression and HLA-A, B, (serology), DR, DQ and C4A gene deletion (restriction fragment length polymorphism [RFLP] typing) were determined.

RESULTS

Photosensitivity was present in all SLE subjects with anti-Ro antibodies (P=0.001, RR=13.1, CI=1.8, 564). Photosensitivity was further associated with the HLA-A1, C4A gene deletion haplotype. More strikingly, C4A gene deletion was associated with anti-Ro (P=0.008, RR=4.6, CI=1.4, 16.2) and anti-La (P=0.02, RR=11.7, CI=1.4, 549) autoantibodies. This relationship was also significant for anti-Ro antibody in the French Canadian patients (P=0.01, RR=21.3, CI=1.7, 105.3). In contrast, anti-dsDNA autoantibodies were negatively associated with photosensitivity (P=0.02, RR=0.3, CI=0.07, 0.8) and correlated with HLA-DR15 (P=0.006, RR=4.2, CI=1.5, 12.8) and Dw2 (P=0.009, RR=3.9, CI=1.4, 11.9).

CONCLUSION

C4A gene deletion has a previously unrecognized powerful association with anti-Ro and anti-La autoantibodies. These results support the concept of divergent MHC gene associations with autoantibody expression and emphasize the influence of ethnicity on the immunogenetic study of SLE.

Differential expression of isomorphic HLA-DR beta genes is not a sole function of transcription

Cells expressing HLA DR7 contain two functional DR beta genes, DRB1 and DRB4, whose mRNA is present at different levels. We examined whether the mRNA levels are due to differential transcriptional regulation or post-transcriptional regulation. As part of this analysis, a novel series of upstream elements was identified. Analysis of the proximal promoter activity, using a transient expression system, showed that the isomorphic promoter activities of B1 and B4 are about equal. RNase protection analysis of steady-state pre-mRNA and mRNA levels shows that the DR7 B1 pre-mRNA levels are 3 to 4 fold higher than B4 pre-mRNA levels. However, the B1 mRNA levels are increased seven fold relative to the B4 mRNA levels. The disproportionate increase of the mRNA levels relative to the corresponding pre-mRNA levels indicates that regulation also occurs at the post-transcriptional level.

Activation of local cell-mediated immunity in interferon-responsive patients with human papillomavirus-associated lesions

Successful immune response to viral infection, such as human papillomavirus (HPV) infection, involves presentation of viral antigens to the immune system, recruitment of T cells and macrophages, and activation of a diverse array of cytokines. Interferons (IFN) are known to exert immunomodulatory functions via activating these pathways. However, the presence of HPV can interact with this process. We employed a reverse transcription-polymerase chain reaction (RT-PCR)-based method to study this phenomenon in biopsies of patients responding well or poorly to IFN treatment. We found that responders show a delayed-type hypersensitivity (DTH) reaction after IFN treatment, in which TH1 cells (interleukin-2, IL-2, IFN-gamma) and macrophages/NK cells (CD16) predominate. Antigen presentation capability (e.g., upregulation of MHC molecules, cytokines) is also enhanced after IFN treatment in responders. The lack of upregulation of MHC molecules (HLA-DR, beta 2-microglobulin) and certain cytokines (IL-1 alpha, IL-2, IFN-gamma) in nonresponders may be due to the overexpression of HPV early (E7) gene in contrast to responders, where HPV late (L1) gene expression predominates. We concluded that differential HPV expression in infected cells can be responsible for an inappropriate IFN-mediated immune response.

Inheritance of MHC class II genes in IDDM studied in population-based affected and control families

The transmission of HLA-DR and DQ was compared between 46 families with at least one child affected by insulin dependent diabetes mellitis (IDDM) and 43 healthy control families. In the patient families, there was an increased transmission of DR4 (p < 0.025) and DQB1*0302 (p < 0.01) from both parents to the index patient. There was an increased transmission of DQB1*0302 (p < 0.03) from the mothers only. The non-inherited maternal haplotypes showed a significantly decreased frequency (p < 0.01) of positively associated haplotypes (DR4-DQA1* 0301-DQB1*0302, DR3-DQA1*0501-DQB1*0201) compared to all parental haplotypes in the control families. In the control families neither transmission rates nor frequencies of non-inherited haplotypes differed from those expected in the control families. In conclusion, the observed reduction of IDDM-positively associated haplotypes in patient non-inherited maternal haplotypes, but not in non-inherited paternal haplotypes, suggests that tolerance during fetal life to maternal non-inherited HLA molecules may be important to diabetes development.

Human MCF activates monocytes to produce IL-1 but not TNF or CSF-1

Monocyte cytotoxicity inducing factor (MCF) is a novel cytokine which was originally characterized by its ability to induce monocyte cytotoxicity against tumor targets. The present studies were undertaken to define the mechanisms of cytotoxicity. Since the cytotoxic state may be mediated, in part, by the secretion of monokines, MCF's effect on IL-1, TNF and CSF-1 were measured. MCF caused human peripheral blood monocytes to secrete large amounts of IL-1 but not TNF. In contrast monocytes produce CSF-1 in culture and this production was not enhanced by MCF. IL-1 neither appeared to directly lyse the target K562 nor was able to activate macrophages for cytotoxicity. However, IL-1 may be necessary for lysis of K562 by activated macrophages through its cytostatic effect on K562. MCF increased monocyte surface expression of DR-beta (when studied by fluorescent microfluorometry) and messenger RNA for DR-beta after 24 h in culture. These functional studies indicate that MCF is a cytokine with a distinct spectrum of biologic activities whose functions may be mediated by synthesis and secretion of IL-1.

Analysis of restriction fragment length polymorphism for the HLA-DR gene in Japanese patients with sarcoidosis

BACKGROUND

It is commonly assumed that some immunological disorder may play a part in the pathogenesis of sarcoidosis. Previous studies by several groups have shown a significant association with HLA-DR antigens in patients with sarcoidosis. In this study, restriction fragment length polymorphism (RFLP) analysis of the HLA-DR gene was designed to confirm the association at the gene level and to look for a gene rearrangement which may influence susceptibility to sarcoidosis.

METHODS

Thirty two unrelated Japanese patients with sarcoidosis were tested for HLA antigens and subjected to RFLP analysis after digestion with Eco RI, Pst I, Bam HI, Pvu II, and Hind III by using an HLA-DR beta cDNA probe. A group of 47 unrelated healthy Japanese subjects served as controls. Frequencies of each restriction fragment were compared between the patients and the control subjects. Correlation between fragment frequencies and clinical features were also analysed.

RESULTS

No restriction fragments of HLA-DR beta gene were found specific to the patients with sarcoidosis. The RFLP analysis could detect polymorphism of HLA-DR beta genes that was not distinguishable by conventional serological methods. Several restriction fragments of the DR beta gene were seen only in DRw52 positive individuals, and showed higher frequencies in the patients than in control subjects. The patients with these DNA fragments were likely to have limited stage disease with no ophthalmic involvement.

CONCLUSIONS

An association between HLA and sarcoidosis was noted at the DNA level, although no restriction fragments were specific for this disease. RFLP analysis of the HLA gene is a more useful method than the usual HLA typing, and should be the first step in identifying the gene sequence which is connected with susceptibility to sarcoidosis.

1 alpha,25-dihydroxy vitamin D3 modulation of HLA-DR mRNA induced by gamma-interferon in cultured epithelial tumor cell lines

Using three cultured epithelial tumor cell lines, we investigated and analyzed the effects of gamma-interferon (gamma-IFN) and 1 alpha,25-dihydroxy vitamin D3 (1,25-(OH)2D3) on the levels of HLA-DR (alpha) mRNA and HLA-DR (beta) mRNA by Northern blot analysis. After treatment with gamma-IFN alone, the levels of the mRNA increased. Treatment with both gamma-IFN and 1,25-(OH)2D3 at the same time resulted in a significant decrease in the levels of mRNA in K-TL-1, IK-TL-2, and M-TL cells as compared to those induced by gamma-IFN alone.

Comparative studies of the major histocompatibility complex in French Canadian and non-French Canadian Caucasians with systemic lupus erythematosus

OBJECTIVE

To investigate and compare the predisposing role of major histocompatibility complex (MHC) genes in systemic lupus erythematosus (SLE) in French Canadian and non-French Canadian (mainly Anglo-Saxon descent) Caucasian subjects.

METHODS

HLA-A, B, C (serology), DR, and DQ (restriction fragment length polymorphism [RFLP] typing) were determined. RFLP defining a large C4A,21-OHA deletion (Taq I C4) and an Nco I tumor necrosis factor alpha (TNF alpha) RFLP were analyzed in 91 Caucasian Canadians and 91 ethnically matched control subjects.

RESULTS

In the total SLE and non-French Canadian SLE populations, HLA-B8, DR3(DR17), Dw24, DQ2, and the C4A gene deletion were associated with SLE. These HLA specificities and the C4A gene deletion were not significantly increased in French Canadian SLE patients compared with ethnically matched controls. When present in French Canadians, the C4A gene deletion was less closely associated with HLA-DR3(DR17), Dw24, DQ2 than in other Caucasians. HLA-DQ6 was associated with SLE in French Canadians. No association of the 2-allele Nco I TNF alpha RFLP with SLE was found in this population, in either ethnic group.

CONCLUSION

These results support the importance of ethnic background in the study of MHC genes and SLE. The extended HLA-B8,DR3,C4A null haplotype is found mainly in SLE patients of Anglo-Saxon descent, while the DQ6 specificity is associated with SLE in French Canadians. This relatively genetically homogeneous Caucasian population offers the opportunity to study non-HLA-B8,DR3-linked MHC influence in SLE.

HLA-DQ primarily confers protection and HLA-DR susceptibility in type I (insulin-dependent) diabetes studied in population-based affected families and controls

The association between HLA-DR and -DQ and insulin-dependent diabetes mellitus (IDDM) in a defined high-incidence area was analyzed in a total of 58 population-based patients, representing 77% of IDDM patients with age at onset below 16 years, and in 92 unrelated parents in control families without IDDM. HLA haplotypes were confirmed by analyzing first-degree relatives in both groups. Seven different methods were used to analyze risk: (1) odds ratio, (2) absolute risk, (3) haplotype relative risk, (4) transcomplementation relative risk, (5) relative predisposing effects, (6) stratification analysis, and (7) test of predisposing allele on haplotype. DQB1*0302 indicated somewhat higher risk than did DR4, while DR3 had a higher risk than DQB1*0201; however, the 95% confidence intervals of the risk estimates overlapped. The positive association between IDDM and the DQB1*0201-DQA1*0501-DR3 haplotype seems to be due to DR3 or to an unknown linked gene. More important, DQA1*0301 was present among 93% of the patients, and this allele in various transcomplementation combinations with DQB1 alleles showed closer association to IDDM than did any other alleles. The strong negative association of the DQB1*0602 allele also in the presence of either DR4 or DQB1*0302 or both suggests that, in a high-risk population for IDDM, HLA-DQ primarily confers protection, perhaps by induction of tolerance. Consistent with known functions, HLA-DR may primarily confer susceptibility, perhaps by induction of autoreactive T lymphocytes.

Class I associations and frequencies of class II HLA-DRB alleles by RFLP analysis in children with rheumatoid-factor-negative juvenile chronic arthritis

A total of 94 patients with juvenile chronic arthritis (JCA) was tested for HLA class I by serology and for class II by RFLP typing. Early onset JCA (EOPA) is associated with HLA-A2, DR5 and DR8 in both males and females. The combination (joint occurrence) of these JCA associated alleles (A2, DR5, DR8) is frequently seen in patients with chronic iridocyclitis. Late onset pauciarticular disease has an increased frequency of HLA-B27, especially in males. Our data confirm that polyarticular JCA with early childhood onset (< or = 4 years) is associated with DR5 and DR8 and has a different immunogenetic background from polyarticular JCA with later childhood (> 4 years) onset (associated with DR4).

Early-onset autoimmune hepatitis is associated with a C4A gene deletion

BACKGROUND

Autoimmune hepatitis is an immunologically mediated disorder with some similarities to systemic lupus erythematosus, including an association with HLA-A1, B8, DR3. This haplotype includes a C4A, 21-OHA gene deletion. Low serum levels of complement and C4 null alleles have been reported in autoimmune hepatitis, but studies have been at the protein level only.

METHODS

Twenty-four white patients with autoimmune hepatitis were studied by Southern blots using a C4A gene complementary DNA probe. HLA A, B, and C typing was determined using standard microcytotoxicity assays, and DR and DQ specificities were determined by restriction fragment length polymorphism analysis.

RESULTS

Thirteen of 24 patients had the C4A gene deletion compared with 12 of 90 controls. HLA-A1 and B8 were increased in patients with autoimmune hepatitis, as were HLA-DR3 (DR17), Dw24, DQ2. Patients with a C4A gene deletion presented at a younger age than those without the deletion and had significantly lower serum C3 and C4 levels. The C4A gene deletion was associated with HLA-A1, B8, DR3 in all but 1 patient who was HLA-DR3 negative.

CONCLUSIONS

A C4A gene deletion is found in patients with autoimmune hepatitis, especially those presenting at a young age. This complement gene deletion may be an important factor in the development of this disease.

Mhc-DRB and -DQA1 nucleotide sequences of three lowland gorillas. Implications for the evolution of primate Mhc class II haplotypes

Mhc-DRB and -DQA1 second-exon and -DRB 3'-untranslated-region nucleotide sequences of three lowland gorillas with no known family relationship with each other and of two HLA homozygous typing cell lines were determined and compared with published primate Mhc-DRB and -DQA1 sequences. Eleven distinct MhcGogo-DRB second-exon sequences were found, which represent the gorilla counterparts of the HLA-DRB1*03, -DRB1*10, -DRB3, -DRB5, and -DRB6 allelic lineages. One Gogo-DRB second-exon sequence does not have an obvious human counterpart and is tentatively designated Gogo-DRBY*01. The gorilla equivalents of the HLA-DRB2 and -DRB8 loci were identified as judged on Mhc-DRB 3'-untranslated-region sequences. In addition, four different Gogo-DQA1 alleles belonging to three different allelic lineages were detected. The Mhc-DRB-DQA1 haplotypes of these gorillas were deduced based on the obtained Mhc-DRB and -DQA1 sequences and the two published Mhc-DRB haplotypes of the lowland gorilla Sylvia. All deduced Gogo-DRB-DQA1 haplotypes show gene constellations different from known HLA-DRB-DQA1 haplotypes, while some of the Gogo-DRB haplotypes presented here contain more DRB genes than the HLA-DRB haplotypes. Based on phylogenetic trees, bootstrap analyses, and the gorilla, chimpanzee, and human Mhc-DRB haplotypes described, we propose that at least two Mhc-DRB loci, here tentatively designated Mhc-DRBI and -DRBII, existed on an ancient primate Mhc-DRB haplotype. The Mhc-DRB1*01, -DRB1*02 (-DRB1*15 and -DRB1*16), -DRB1*03 (-DRB1*03, -DRB1*08, -DRB1*11, -DRB1*12, -DRB1*13, and DRB1*14), and -DRB1*10 allelic lineages and -DRB3 and -DRBY loci probably evolved from the hypothetical primate Mhc-DRBI locus, whereas the present primate Mhc-DRB2, -DRB4, and -DRB6 loci originate from the ancient Mhc-DRBII locus of this core primate Mhc-DRB haplotype.

Distinct associations of HLA class II genes with inflammatory bowel disease

BACKGROUND

There are relatively few studies of HLA class II association either with Crohn's disease (CD) or ulcerative colitis (UC). The few available association studies have been carried out by serological techniques, and the results from these studies are inconclusive.

METHODS

The association between HLA class II genes was studied using molecular genotyping in combination with allele-specific oligonucleotide hybridization by polymerase chain reactions.

RESULTS

In UC (n = 74), we observed a positive association with the HLA DR2 allele (P = 0.008) and negative associations with the DR4 (P = 0.018) and DRw6 (P = 0.028) when compared with ethnically matched controls (n = 77). No associations were observed with any DQ alleles. In contrast, in CD (n = 95) we observed a positive association with the combination of DR1 and DQw5 alleles (P = 0.021). Furthermore, stratifying DR1 and DQw5 alleles indicated that neither allele was independently associated with CD, suggesting that the association was with the haplotype rather than either of the alleles individually. A suballele of DQw5, DQB1*0501, contributed this haplotypic association (P = 0.012).

CONCLUSIONS

DR and DQ molecules firmly separate UC and CD on genetic grounds, suggesting that the contribution of the HLA class II genes to the disease susceptibility is quite different for the two disorders.

Modulation of interferon-gamma-induced HLA-DR expression on the human keratinocyte cell line SCC-13 by ultraviolet radiation

Cell surface expression of major histocompatibility determinants on epidermal keratinocytes is a characteristic feature of a number of inflammatory dermatoses and in all likelihood is caused by diffusion of human leukocyte antigen (HLA)-DR-inducing cytokines from cells present in the dermal mononuclear cell infiltrate. Many of these same disorders respond to ultraviolet (UV) radiation phototherapy. Using the human SCC-13 keratinocyte cell line as a model, UV radiation was found to inhibit interferon-gamma-induced HLA-DR expression. Inhibition correlated closely with decreased steady-state levels of HLA-DR mRNA. These findings provide evidence that the therapeutic effect of UV radiation phototherapy may be mediated by its capacity to down-regulate cytokine-induced keratinocyte HLA-DR expression.

Contrasting molecular patterns of MHC class II alleles associated with the anti-Sm and anti-RNP precipitin autoantibodies in systemic lupus erythematosus

OBJECTIVE

To find evidence of a potential genetic predisposition to the anti-Sm or anti-RNP precipitin autoantibody responses.

METHODS

HLA-DR and DQ alleles determined by restriction fragment length polymorphism and/or oligotyping in 49 subjects with either anti-Sm alone or anti-RNP alone were compared with those in 139 race-matched normal control subjects and 59 race-matched lupus patients without anti-Sm and anti-RNP autoantibodies.

RESULTS

Black patients with anti-Sm precipitin had increased frequencies of HLA-DR2 and the DQw6-associated DQA1*0102 (P = 0.007, odds ratio [OR] = 6.7) and DQB1*0602 (P = 0.001, OR = 9.1) chain alleles compared with normal black control subjects. Black patients with anti-RNP precipitin showed significant increases in the DQw5-associated DQA1*0101 (P = 0.03, OR = 5.5) and DQB1*0501 (P = 0.002, OR = 23.3) chain alleles compared with lupus patients without anti-Sm or RNP. While patients with anti-RNP precipitin showed an increased frequency of the DQw8-associated allele DQB1*0302 (P = 0.02, OR = 3.7) compared with normal controls, as well as an increased frequency of the DQw5-associated alleles DQA1*0101 and DQB1*0501 (P = 0.05, OR = 4.2) compared with lupus patients without anti-Sm or RNP. There were no specific HLA-DR2 or DR4 subtype associations found with either anti-Sm or RNP precipitin autoantibodies.

CONCLUSION

There are distinct patterns of major histocompatibility complex class II allele associations with the anti-Sm versus the anti-RNP precipitin autoantibody responses, and HLA-DQ associations may be more primary than HLA-DR associations.

Comparative anatomy of the primate major histocompatibility complex DR subregion: evidence for combinations of DRB genes conserved across species

The class II region of the human major histocompatibility complex (HLA) is made up of three major subregions designated DR, DQ, and DP. With the aim of gaining an insight into the evolution and stability of DR haplotypes, a total of 63 cosmid clones were isolated from the DR subregion (Gogo-DR) of a western lowland gorilla. All but one of these cosmid clones were found to fall into two clusters. The larger cluster, A, was defined by 41 overlapping cosmid clones and contained a DRB gene segment made up of exons 4 through 6 and four DRB genes, designated Gogo-DRB6, Gogo-DRB5*01, Gogo-DRB8, and Gogo-DRB3*01. The total length of this cluster was approximately 180 kb. The second cluster, B, encompassed a contiguous DNA stretch of approximately 145 kb and was composed of 21 overlapping cosmid clones. Cluster B contained three DRB genes, designated Gogo-DRB1*08, Gogo-DRB2, and Gogo-DRB3*02. One cosmid clone (WP1-9) containing a DRB pseudogene could not be linked to either cluster A or B. Neither the organization of cluster A nor that of cluster B was identical to that of known HLA-DR haplotypes. However, two gorilla DRB genes, Gogo-DRB6 and Gogo-DRB5*01, the human counterparts of which are linked in the HLA-DR2 haplotype, were found to be located next to each other in cluster A. The arrangement of the Gogo-DRB genes in cluster B, which is presumed to be the gorilla DR8 haplotype, was similar to that of HLA-DR3/DR5/DR6 haplotypes and to that of the presumed ancestral HLA-DR8 haplotype.(ABSTRACT TRUNCATED AT 250 WORDS)

Linkage between HLA-DRB1 and -DRB3 types in the Japanese population analyzed by oligonucleotide genotyping

We analyzed linkage between HLA-DRB1 and -DRB3 types in 219 Japanese donors by oligonucleotide genotyping. In the Japanese population, DRB1*1201 was linked with DRB3*0101 in all donors analyzed; in contrast, most Caucasian DRB1*1201 is known to be linked with DRB3*02(01/02) (*0201 or *0202). However, most DRB1*1202 was linked with DRB3*0301. Thus, the two DRw12-related DRB1 types are linked with DRB3 types distinct from each other. All the three DRw14-related DRB1 types, DRB1*1401, DRB1*1402, and DRB1*1405, were linked with DRB3*02(01/02) in the Japanese population, contrasting with the known linkage between DRB1*1402 and DRB3*0101 in other ethnic populations. The serologically "blank" DR type, DRB1*1403, was linked with DRB3*0101. Other DRB1 types, DRB1*0301, DRB1*11(01/04) (*1101 or *1104), and DRB1*13(01/02) (*1301 or *1302) in the Japanese population were linked mostly with the same DRB3 types, like those known in other ethnic populations.

Studies of the HLA class II alleles involved in human responses to ragweed allergensAmbrosia artemisiifoliaV (Ra5S) andAmbrosia trifidaV (Ra5G)

Previous studies have associated skin test sensitivity and specific IgE response to Ambrosia artemisiifolia V (Amb a V) with HLA-DR2, and to Ambrosia trifida V (Amb t V) with HLA-DRw52 haplotypes in atopic individuals. Using HLA class II typing by restriction fragment length polymorphism (RFLP) analysis with DRB, DQB and DQA DNA probes to define the HLA-D alleles, we have demonstrated the association of the DQw6 in 16 out of 16 (100%) Amb a V-responsive individuals, compared to 3 out of 18 (17%) ragweed-sensitive but Amb a V-nonresponsive individuals (p = 5.7 x 10(-6), RR greater than 75). We suggest that the DQw6 association with Amb a V sensitivity may be a reflection of an association with the DQA*0102 allele. This suggests an association of a particular HLA class II allele with an immune response to a well-characterized antigen (Amb a V). The HLA-DRw52 haplotypes in the Amb t V-sensitive individuals are not of one particular subtype. The HLA-DRw52 association with Amb t V sensitivity may reside in homologous DRB1 alleles linked on HLA-DRw52-bearing haplotypes.

The evolutionary origin of the HLA-DR3 haplotype

The human HLA-DR3 haplotype consists of two functional genes (DRB1*03 and DRB3*01) and one pseudogene (DRB2), arranged in the order DRB1...DRB2...DRB3 on the chromosome. To shed light on the origin of the haplotype, we sequenced 1480 nucleotides of the HLA-DRB2 gene and long stretches of two other genes, Gogo-DRB2 from a gorilla, "Sylvia" and Patr-DRB2 from a chimpanzee, "Hugo". All three sequences (HLA-DRB2, Gogo-DRB2, Patr-DRB2) are pseudogenes. The HLA-DRB2 and Gogo-DRB2 pseudogenes lack exon 2 and contain a twenty-nucleotide deletion in exon 3, which destroys the correct translational reading frame and obliterates the highly conserved cysteine residue at position 173. The Patr-DRB2 pseudogene lacks exons 1 and 2; it does not contain the twenty-nucleotide deletion, but does contain a characteristic duplication of that part of exon 6 which codes for the last four amino acid residues of the cytoplasmic region. When the nucleotide sequences of these three genes are compared to those of all other known DRB genes, the HLA-DRB2 is seen as most closely related to Gogo-DRB2, indicating orthologous relationship between the two sequences. The Patr-DRB2 gene is more distantly related to these two DRB2 genes and whether it is orthologous to them is uncertain. The three genes are in turn most closely related to HLA-DRBVI (the pseudogene of the DR2 haplotype) and Patr-DRB6 (another pseudogene of the Hugo haplotype), followed by HLA-DRB4 (the functional but nonpolymorphic gene of the DR4 haplotype). These relationships suggest that these six genes evolved from a common ancestor which existed before the separation of the human, gorilla, and chimpanzee lineages. The DRB2 and DRB6 have apparently been pseudogenes for at least six million years (myr). In the human and the gorilla haplotype, the DRB2 pseudogene is flanked on each side by what appear to be related genes. Apparently, the DR3 haplotype has existed in its present form for more than six myr.

The use of DNA heteroduplex patterns to map recombination within the HLA class II region

Differential DNA heteroduplex patterns were used to investigate inheritance of HLA class II region genes in a family where a living related kidney transplant was under consideration. Serologic typing of the family members for HLA class I (HLA-A, B, and C) and class II (HLA-DR and DQ) alleles indicated that the patient (109) and one sibling (126) had inherited the same maternal and paternal HLA alleles. However, a strong reciprocal mixed lymphocyte response implied that these two individuals were not completely HLA identical. Serologic typing for HLA-DQ was confirmed by allele-specific oligonucleotide typing family members for HLA-DQ alpha and beta genes. To assess a possible nonidentical gene(s), DNA was amplified from all family members at the second exon of the DR beta, DQ alpha, DP alpha, and DP beta genes and the products were analyzed by DNA heteroduplex formation. This method showed that individuals 109 and 126 were identical at DR and DQ but differed at DP. This difference was confirmed by allele-specific oligonucleotide hybridization and indicated that 126 had inherited a recombinant maternal chromosome with a cross-over occurring in the region between the DQ beta and DP alpha genes. These data demonstrate the applicability of DNA heteroduplex patterns in establishing identity-nonidentity of alleles in the major histocompatibility complex.

Post-transcriptional regulation of MHC class II expression in human T cells

Human T lymphocytes are among those cells which are cell surface class II- in the resting state, but can be induced to express class II following treatment with appropriate stimulators. Although resting T cells do not express detectable surface class II, cell surface class II can be detected on purified T cells as early as 30 min following stimulation with PHA and PMA, well before the initiation of DNA synthesis, and the percentage of positive cells gradually increases with time. One hypothesis explaining this very rapid surface expression of class II is that the genes can be regulated post-transcriptionally in T cells. To test this, we used nuclear run-on assays to measure the transcriptional rate of diverse class II genes in resting and activated T cells. Our results demonstrated that transcripts for DR, DP, and DQ could be detected in cells which were neither dividing nor transcribing mRNA for another marker of T cell activation, the IL-2 gene. Northern blot analysis demonstrated low to moderate steady-state levels of DR beta mRNA in these cells. Moreover, treatment of activated T cells with cycloheximide resulted in superinduction of class II for DR, DQ, and DP. These results suggest that resting T cells can transcribe mRNA for class II genes, but that they do not express the protein product on the cell surface in a detectable way until following activation. In addition, they suggest that there may be a protein factor which negatively influences class II levels in T cells. Thus, the regulation of class II in T cells is complex and involves post-transcriptional regulation, at least in part.

Molecular genetic studies of major histocompatibility complex genes in children with juvenile dermatomyositis: increased risk associated with HLA-DQA1 *0501

Juvenile dermatomyositis (JDMS) is an inflammatory disease associated with HLA-DR3. We therefore undertook molecular genetic studies of HLA region genes to determine whether HLA-DR3 itself confers susceptibility to JDMS or whether susceptibility is conferred by alleles in linkage disequilibrium with HLA-DR3. Our results indicate that JDMS is associated with the HLA-DQA1 allele DQA1 *0501 on non-DR3 haplotypes in Caucasian JDMS. Furthermore, the reported of association between the C4A gene deletion and JDMS is likely due to linkage disequilibrium with HLA-DR3.

Prenatal diagnosis of 21-hydroxylase deficiency by RFLP analysis of the 21-hydroxylase, complement C4, and HLA class II genes

In 19 pregnancies at risk for 21-hydroxylase deficiency (21OHD) in 18 families with at least one affected child, prenatal diagnosis was performed by RFLP analysis using the enzymes Taq I and EcoRI and the DNA probes specific for the 21OH genes, the closely linked complement C4 genes and the highly polymorphic HLA class II genes DRB, DQB, and DPB. For fetal DNA analysis either chorionic villi or cultivated amniotic cells were used. In all 19 cases, a clear prenatal diagnosis was possible either with the 21OH probe alone or in most cases, by combining the results of the different closely linked loci.

A model for the role of HLA-DQ molecules in the pathogenesis of juvenile chronic arthritis

Restriction fragment length polymorphism (RFLP) typing of MHC-class II loci DRB, DQA1, DQB1, DQA2 and DPB1 was performed in 94 patients with seronegative juvenile chronic arthritis (JCA) and 184 random controls. Analysis of allele frequencies and MHC-class II 4-loci haplotypes indicate: (1) Susceptibility to JCA is more strongly associated with the HLA-DQ subregion than with the HLA-DR subregion, especially in early onset pauciarticular JCA (EOPA-JCA). (2) Haplotype and sequence analysis show two independent MHC-class II associations for susceptibility to EOPA-JCA, one located in DQA1, the other in DPB1. (3) Two RFLP defined patterns of the DQA1 locus, DQA1.5 (DQA1*0501) and DQA1.8 (DQA1*0401, *0601) are strongly associated with the disease. (4) Analysis of amino-acid (AA) sequences coded in exon 2 of DQA1 reveals an AA sequence of six AAs common to all three associated DQA1 alleles. This suggests a model that includes a functional role for HLA-DQ molecules in the pathogenesis of JCA.

Orientation of HLA-DNA gene and identification of a CpG island-associated gene adjacent to DNA in human major histocompatibility complex class II region

We have constructed the detailed physical map of the HLA class II gene region by the pulsed field gel electrophoresis (PFGE) and cosmid walking technique. In this process, the DNA gene was found to be located telomeric to DPA1 with the 5'----3' orientation which is the same as the DPA1 and DPA2 genes, but opposite to the DQA1, DQA2 and DRA genes. This orientation is reverse to that of the counterpart gene in the rabbit major histocompatibility complex region. About 30 kb downstream from the DNA gene towards DOB, a CpG island characterized by clustered sites for rare cutting restriction enzymes and frequently associated with the 5' end of housekeeping genes was identified by PFGE and cosmid walking. From a complementary DNA (cDNA) library constructed from a Epstein-Barr virus-transformed B-cell line, a cDNA clone was isolated using the genetic probe from this CpG island. Its nucleotide sequences suggested that it represented a new non-HLA gene with a single copy which was of little genetic polymorphism and named NAT (DNA-associated transcript). Northern blot analysis showed that the NAT gene was expressed with a 4-kb transcript in all of tissues examined so far.

Primate DRB6 pseudogenes: clue to the evolutionary origin of the HLA-DR2 haplotype

The HLA-DR2 haplotype contains three beta-chain encoding DRB genes and one alpha-chain encoding DRA gene. Of the three DRB genes, two are presumably functional (HLA-DRB1 and HLA-DRB5), whereas the third (HLA-DRBVI) is a pseudogene. A pseudogene closely related to HLA-DRBVI is present in the chimpanzee (Patr-DRB6) and in the gorilla (Gogo-DRB6). We sequenced the HLA-DRBVI and Patr-DRB6 pseudogenes (all exons and most of the introns), and compared the sequence to that of the Gogo-DRB6 gene (of which only the exon sequence is available). All three pseudogenes seem to lack exon 1 and contain other deletions responsible for shifts in the translational reading frame. At least the HLA-DRBVI pseudogene, however, seems to be transcribed nevertheless. The chimpanzee pseudogene contains two inserts in intron 2, one of which is an Alu repeat belonging to the Sb subfamily, while the other remains unidentified. These inserts are lacking in the human gene. A comparison with sequences published by other investigators revealed the presence of the HLA-DRBVI pseudogene also in the DR1 and DRw10 haplotypes. Measurements of genetic distances indicate DRB6 to be closely related to the DRB2 pseudogene and to the HLA-DRB4 functional gene. In humans, gorillas, and chimpanzees, the DRB6 pseudogene is associated with the same functional gene (DRB5) indicating that this linkage disequilibrium is at least six million years old and that DR2 is one of the oldest DR haplotypes in higher primates.

Isolation of probes specific to human chromosomal region 6p21 from immunoselected irradiation-fusion gene transfer hybrids

A hybrid cell line (R21/B1) containing a truncated human chromosome 6 (6pter-6q21) and a human Y chromosome on a hamster background was irradiated and fused to A23 (TK-) or W3GH (HPRT-) hamster cells. Clones containing expressed HLA class I genes (4/40) were selected using monoclonal antibodies. These clones were recloned and analyzed with a panel of probes from the HLA region. One hybrid (4G6) contained the entire HLA complex. Two other hybrids (4J4 and 4H2) contained only the HLA class I region, while the fourth hybrid (5P9) contained HLA class I and III genes in addition to other genes located in the 6p21 chromosomal region. In situ hybridization showed that the hybrid cells contained more than one fragment of human DNA. Alu and LINE PCR products were derived from these cells and compared to each other as well as to products from two somatic cell hybrids having the 6p21 region in common. The PCR fragments were then screened on conventional Southern blots of the somatic cell hybrids to select a panel of novel probes encompassing the 6p21 region. In addition, the origin of the human DNA fragments in hybrid 4J4 was determined by regional mapping of PCR products.

HLA-DRB3 typing by restriction digestion of locus-specific amplified DNA

Locus HLA-DRB3 codes for the serologically defined supertypic specificity DRw52 in HLA-DR3, -5 and -w6 haplotypes. Three specificities of DRw52 (DRw52a, -b and -c) can further be distinguished by cellular techniques or by DNA typing with allele-specific oligonucleotide probes. These specificities were recently reported to have significant importance in antigen presentation. To avoid a time-consuming hybridization procedure, we have developed a simple typing system using PCR and subsequent digestion by allele-specific restriction endonucleases. A system was established with locus-specific amplification of HLA-DRB3 and digestion by the enzymes KpnI, ScaI and HinfI which recognize unique restriction sites within the amplified region. This allowed HLA-DRB3 typing on agarose gel by determining whether the amplification product has been digested or not. This typing system was compared to conventional oligotyping by analyzing 145 RFLP-typed individuals for their DRw52 specificity using both methods. Agarose typing correlated well with oligotyping and was shown to be more simple and practical even in heterozygous individuals.

Correlation of phenotypic and genetic heterogeneity in cystic fibrosis: variability in sweat electrolyte levels contributes to heterogeneity and is increased with the XV-2c/KM19 B haplotype

We have reinvestigated a classification of clinical heterogeneity among cystic fibrosis (CF) patients that we previously reported and investigated the possible relationship of the identified CF subgroups to haplotypes around the CF gene and to HLA-DR haplotypes. Age-corrected values for sweat electrolytes, rate of progression of lung disease as assessed by Brasfield chest x-ray scores, and severity of pancreatic insufficiency as assessed by daily supplemented enzyme dosage were obtained for 55, 59, and 59 patients, respectively. XV-2c and KM19 RFLPs were determined by hybridization to TaqI and PstI digests of human genomic DNA, respectively, and analysis of mutations by PCR amplification followed by allele-specific oligo-deoxynucleotide hybridization was performed for 29 patients. HLA-DR restriction fragment length polymorphisms (RFLPs) were determined by hybridization of cDNA beta 1 and genomic DQ alpha probes to TaqI digests of human genomic DNA. The results show that the previous subdivision on the basis of age-corrected levels of sweat electrolytes, as well as measures of severity of lung disease and pancreatic disease, is valid. In addition, the C and D haplotypes are associated with lower age-corrected sweat sodium level. No significant relationship between CF haplotypes and the other two disease variables or between HLA-DR haplotypes and any of the clinical variables was found.

A monoclonal antibody with broad anti-HLA-DR activity fails to bind to DRw11/Dw5: possible effect of a unique polymorphism on the beta 1 domain alpha-helix

We describe the generation and characterization of a murine monoclonal antibody with broad anti-HLA-DR beta activity, but which does not recognize DRw11/Dw5. A BALB/c mouse was immunized with a human alloreactive T-cell clone, with the intention of generating monoclonal anti-T-cell-receptor antibodies. In the course of screening the resulting hybridomas, a clone was detected which secreted an antibody (MP2) with anti-HLA-DR activity. This was shown by flow cytometry as well as immunoprecipitation followed by gel electrophoresis. Flow cytometry experiments using transfectants bearing hybrid human/murine class II molecules demonstrated that MP2 binds to the DR beta chain. MP2 bound to a wide range of Epstein-Barr-Virus-transformed cell lines and transfectants expressing different DR beta 1 and DR beta 3 subtypes: the only exceptions were three transfectants expressing DRw11/Dw5. One of these (RGT1) was shown to be functionally normal in DRw11-restricted alloreactive and antigen-specific systems. The specificity of MP2 was confirmed in functional assays: it was able to inhibit the recognition of DR1 and DRw15 but not DRw11 by alloreactive T-cell clones. Previously reported sequence data show that the beta chain of DRw11 differs from all other DR and DQ beta chains at position 58 by a glutamic acid for alanine substitution. This may account for the inability of DRw11/Dw5 to be recognized by MP2. The data emphasize the value of transfectants in defining precisely the allelic and chain specificity of anti-major-histocompatibility-complex (MHC) antibodies, and illustrate the influence that inaccessible residues can have on the conformation of MHC molecules.

An unusual form of alternative splicing in the HLA-DNA gene

The HLA-DNA gene of the human major histocompatibility complex (MHC) produces RNA transcripts of unusual size compared to the 1.3 kilobase (kb) transcripts of other class II genes. Several cDNA clones derived from HLA-DNA transcripts were isolated, including a full-length 3.5 kb cDNA named DN1. Sequence analysis of DN1 demonstrated that the 3.5 kb transcript is fully spliced, contains a long 3' untranslated region, and encodes an apparently normal class II alpha chain. Two other cDNA clones, DN2 and DN7, revealed an alternative splice that resulted from the use of a splice acceptor upstream of the second exon encoding the alpha 1 domain. The translation product of this alternative transcript would share the signal sequence of the DN alpha chain but would otherwise be unrelated. Removal of the signal sequence would yield a highly basic peptide of 42 amino acids. RNA was prepared by in vitro transcription of DN1 and DN2, and was used to direct protein synthesis in a rabbit reticulocyte system. The product of DN1 had an apparent relative mass of 25,000, whereas the product of DN2 was a peptide with a relative mass of about 6000. The alternatively spliced RNA represents about 1/10 of the transcripts from the HLA-DNA gene in the cells tested, which included transformed B-cell lines as well as normal blood cells and thymus cells.

RFLP analysis of HLA-DR5 haplotypes

The analysis of HLA-DR5 haplotypes unravelled a new DRB3 polymorphism and permitted the identification of various associations between alleles of the DRB1 and DRB3 loci. This new polymorphism consists of a 10.5 kb Taq1 restriction fragment which was encountered in an African-American family (JS). In Caucasoids, the DRw11 allele has been previously observed only in association with the DRw52b allele. RFLP and oligonucleotide typing of HLA-DRw52 alleles associated with DRw11 showed, however, that 4 Caucasoid individuals from our panel carried the DRw52a allele and 1 the DRw52c allele. Similarly, DRw12, which is usually associated with DRw52b, was encountered with DRw52a in 1 Chinese and with DRw52c in an African-American and a Chinese panel member. The study of DRB3 alleles associated with DRw11 and DRw12 indicates that, similar to serology, RFLP studies become particularly informative when individuals of different races and ethnic origins are studied.

Detection of complex alleles by direct analysis of DNA heteroduplexes

DNA molecules derived from three alleles of the HLA-DRB3 locus and differing from each other at several nucleotide sites were denatured and cross-hybridized. Each allelic combination was found to generate a pair of heteroduplexes of different mobility. Their retardation as compared to homoduplexes was proportional to the number of mismatches. In each heteroduplexes pair the component possessing the highest number of Pyr-Pyr oppositions was the most retarded. The results are those predicted by a theoretical model implying a correlation between base-pair opening and bending of the DNA double helix. These observations introduce a new HLA typing method at the genomic level and indicate an experimental approach to the analysis of the superhelical DNA conformation as related to different types of base oppositions.

Establishment and characterization of five human malignant mesothelioma cell lines derived from pleural effusions

Malignant mesothelioma (MM) is an aggressive tumour of the serosal cavities which is associated with exposure to asbestos. Studies of this tumour have been limited by a paucity of well-characterized human MM cell lines. In this study, 5 human MM cell lines were established from pleural effusions of patients with this malignancy. All 5 patients were males with known crocidolite asbestos exposure, who had received no treatment for their disease and in whom the diagnosis was confirmed by cytology, histology and electron microscopy (EM). These lines have been in culture from 11 to 25 months, and all of them for more than 18 passages. The appearance of the cells in culture was extremely varied; in 3 of the lines they were spindle-shaped with few vacuoles (JU77, LO68 and ONE58); in 1 line they had a thick, stellate shape with vacuoles (NO36) and in 1 they were very pleomorphic in both shape and size with irregular membranes and numerous vacuoles [DeH128 (M)]. Upon reaching confluence, cells in 3 of the 5 lines assumed the cobblestone-like pattern characteristic of epithelial-type cells, whereas in the other 2 (LO68 and ONE58) they remained spindle-shaped. All 5 lines demonstrated a loss of contact inhibition (i.e., piling) at confluence. Minimum doubling times varied significantly from 18 hr (JU77) to more than 30 hr [DeH128 (M)]. Cytological examination showed characteristic mesothelial/mesothelioma morphology, and epithelial membrane antigen (EMA) and cytokeratin were demonstrated in cells from all 5 lines. These cells lacked CEA and epithelial mucin. The presence of cell junctions, glycogen and numerous long, thin, branching microvilli was readily demonstrable by EM. All lines had abnormal karyotypes, with the modal chromosome number varying from 40 to 80. Variable chromosome numbers, numerous structural rearrangements and unrecognizable marker chromosomes were readily observed; however, the only consistent change seen was del 6q21 in 4 of the 5 lines. The establishment of these 5 cultured human MM cell lines now provides an opportunity for comparative study of several aspects of the biology of MM in vitro as well as screening new treatment modalities.

Interferon-gamma activates co-ordinate transcription of HLA-DR, DQ, and DP genes in cultured keratinocytes and requires de novo protein synthesis

The purpose of this study was to determine the effect of interferon-gamma on keratinocyte major histocompatibility complex class II gene transcription. Transformed human foreskin keratinocytes (SVK14 cells) were incubated with recombinant IFN-gamma in the presence or absence of the protein synthesis inhibitor cycloheximide. Total cellular RNA was extracted from the cells and Northern blot analysis carried out using cDNA probes for all the functional class II genes. We report that 1) there is co-ordinate activation of all the class-II genes; 2) the rate of transcription varies between gene loci after activation; and 3) de novo protein synthesis is required for IFN-gamma activation of class II transcription.

Evaluation of HLA-class II identity between unrelated individuals by serological typing, DNA-RFLP method, and mixed lymphocyte reaction

Seven groups, each consisting of two to nine unrelated HLA-A, -B, and -DR serologically identical individuals, were analyzed by DNA-restriction fragment length polymorphism (RFLP) and mixed lymphocyte reactions (MLR) in order to evaluate HLA-class II identity between unrelated individuals and to assess the importance of HLA-class II incompatibilities detected by DNA-RFLP in the allogeneic reactions. It is clear that DNA-RFLP represents a powerful typing method for HLA-DR, -DQ, and -DP since the combinations of the RFLP band patterns define all the serological specificities and most of the cellular specificities to give a highly accurate typing. This report shows that an HLA-DP incompatibility induces proliferation in primary mixed lymphocyte culture (MLC) between unrelated HLA-A, -B, -DR, -DQ, and -DW identical individuals, which may suggest the importance of this molecule as a transplantation antigen, especially for unrelated bone marrow transplantations. Still, an isolated HLA-DPw4/HLA-DP a disparity did not induce any proliferation in MLC. Moreover, our results show that DQw7 (w3)/DQw8 (w3) disparity associated with HLA-DR4 represents a nonfunctional incompatibility in MLR. The HLA-Dw subtypes of HLA-DR specificities can induce a high proliferative response in MLC. The HLA-Dw subtypes of HLA-DR specificities can induce a high proliferative response in MLC. Finally, DNA-RFLP typing represents a reliable method for the selection of histocompatible donor-recipient pairs and could potentially reduce many logistic problems and delays in live-donor transplantation, especially for unrelated bone marrow transplantation.

The chimpanzee major histocompatibility complex class II DR subregion contains an unexpectedly high number of beta-chain genes

The major histocompatibility complex (MHC) class II DR subregion of the chimpanzee was studied by restriction fragment length polymorphism (RFLP) analysis. Genomic DNA obtained from a panel of 94 chimpanzees was digested with the restriction enzyme Taq I and hybridized with an HLA-DR beta probe specific for the 3' untranslated (UT) region. Such a screening revealed the existence of 14 distinct DRB/Taq I gene-associated fragments allowing the definition of 11 haplotypes. Segregation studies proved that the number of chimpanzee class II DRB/Taq I fragments is not constant and varies from three to six depending on the haplotype. Comparison of these data with a human reference panel manifested that some MHC DRB/Taq I fragments are shared by man and chimpanzee. Moreover, the number of HLA-DRB/Taq I gene-associated fragments detected in a panel of homozygous typing cells varies from one to three and corresponds with the number of HLA-DRB genes present for most haplotypes. However, a discrepancy is observed for the HLA-DR4, -DR7, and -DR9 haplotypes since a fourth HLA-DRB pseudogene present within these haplotypes lacks its 3' UT region and thus is not detected with the probe used. These results suggest that chimpanzees have a higher maximum number of DRB genes per haplotype than man. As a consequence, some chimpanzee haplotypes must show a dissimilar organization of the MHC DR subregion compared to their human equivalents. The implications of these findings are discussed in the context of the trans-species theory of MHC polymorphism.

HLA-D region genes associated with autoantibody responses to histidyl-transfer RNA synthetase (Jo-1) and other translation-related factors in myositis

Myositis has been associated with HLA-B8 and DR3, especially in white patients with polymyositis and serum anti-Jo-1 antibodies. Twenty-eight patients with myositis and serum translation-related autoantibodies anti-Jo-1, anti-PL-7, anti-PL-12, anti-KJ, and anti-SRP were studied for HLA class II specificities by Southern blotting with HLA-DR beta, DQ beta, and DQ alpha probes. The association of HLA-DR3 (DRw17) with anti-Jo-1 antibodies in white myositis patients was confirmed (P = 0.003, relative risk 8.9). However, HLA-DRw52 haplotypes, regardless of subtype, were present in all of the white and black patients with serum anti-Jo-1 and other translation-related autoantibodies. Moreover, one anti-Jo-1 positive patient had HLA-DRw8, an HLA-DRw52 haplotype on which the DR beta 3 gene has been partially deleted. No HLA-DQ specificity or allele was common to all patients. The HLA-DR3, DR5, DRw6, and DRw8 haplotypes, which bear the HLA-DRw52 specificity, share the most homology in the DR beta 1 first hypervariable region at amino acid positions 9-13. Thus, this DR beta 1 region appears to be the most likely candidate "epitope" for translation-related autoimmune responses in inflammatory myositis.