Biodegradability enhancement of waste lubricating oil regeneration wastewater using electrocoagulation pretreatment

As a sustainable management of fossil fuel resources and ecological environment protection, recycling used lubricating oil has received widespread attention. However, large amounts of waste lubricating-oil regeneration wastewater (WLORW) are inevitably produced in the recycling process, and challenges are faced by traditional biological treatment of WLORW. Thus, this study investigated the effectiveness of electrocoagulation (EC) as pretreatment and its removal mechanism. The electrolysis parameters (current density, initial pH, and inter-electrode distance) were considered, and maximal 60.06% of oil removal was achieved at a current density of 15 mA/cm2, initial pH of 7, and an inter-electrode distance of 2 cm. The dispersed oil of WLORW was relatively easily removed, and most of the oil removal was contributed by emulsified oil within 5-10 μm. Gas chromatography-mass spectrometry (GC-MS) analysis revealed that effective removal of the biorefractory organic compounds could contribute to the improvement of biodegradability of WLORW. Thus, the 5-day biochemical oxygen demand/chemical oxygen demand ratio (BOD5/COD) was significantly enhanced by 4.31 times, which highly benefits future biological treatment. The routes of WLORW removal could be concluded as charge neutralization, adsorption bridging, sweep flocculation, and air flotation. The results demonstrate that EC has potential as an effective pretreatment technology for WLORW biological treatment.

[Correlational verification of drug-induced liver injury with HLA-B*35:01 allele due to Polygonum multiflorum]

In order to verify the correlation between Polygonum multiflorum-induced liver injury and HLA-B*35 : 01 alleles, six hospitalized patients diagnosed with Polygonum multiflorum-induced liver injury (PM-DILI) were selected, and their clinicopathological data were collected. Simultaneously, blood HLA-B* 35 : 01 allele detection was performed. Among the six PM-DILI cases, 4 were male, aged 38.83 ± 10.13 years old. The types of liver injury were hepatocellular injury types in all, and the severity of liver injury in five cases was grade 3. The histological presentations were acute hepatitis and acute cholestatic hepatitis. PM-DILI cases were all HLA-B*35:01 carriers, with a carrier rate of 100%. This finding indicates that PM-DILI is significantly correlated with HLA-B*35:01 alleles. Therefore, HLA-B*35 : 01 alleles can be used as an important predictive indicator for PM-DILI.

Si-Miao-Yong-An (SMYA) Decoction May Protect the Renal Function Through Regulating the Autophagy-Mediated Degradation of Ubiquitinated Protein in an Atherosclerosis Model

Hyperlipidemia is common, and its renal toxicity has attracted a great deal of attention. Si-miao-yong-an (SMYA) is a famous ancient decoction of traditional Chinese medicine (TCM), which is still widely used in clinical treatment. In this study, we observed and explored its efficacy and mechanism in protecting renal function in an atherosclerosis model. The results showed that the serum, Cr urinal KIM-1, and NGAL were significantly decreased in SMYA group. Although SMYA failed to alleviate the lipid accumulation, decrease p-NFκB, or increase SOD in kidney tissue, the levels of ubiquitinated protein and P62 were decreased in SMYA group. What is more, a higher LC3 II level was observed in the SMYA group. In conclusion, these data indicated that SMYA decoction may protect renal function in hyperlipidemia via regulating the autophagy-mediated degradation of ubiquitinated protein.

Comparison of oncolytic adenoviruses for selective eradication of oral cancer and pre-cancerous lesions

Oncolytic adenoviruses are being investigated as potential anti-cancer agents. Selective lytic replication in cancer cells is essential for an effective and safe treatment. In this study, we compared 11 oncolytic adenoviruses in relevant cell cultures to assess their use for treating oral cancer and pre-cancerous lesions. We determined the cytotoxicity of oncolytic adenovirus infection and calculated selectivity indices for cytotoxicity to cancer cells compared with normal oral keratinocytes and fibroblasts. Keratinocytes were very sensitive to wild-type adenovirus serotype 5 (Ad5); 1- to 3-log more than head and neck squamous cell carcinoma (HNSCC) cells. The potencies of oncolytic adenoviruses to kill HNSCC cells within 7 days after infection ranged from approximately 10 times less potent to approximately 10 times more potent than Ad5. The selectivity indices determined on fibroblasts and keratinocytes differed markedly. Two oncolytic adenoviruses were more selective than Ad5 for HNSCC cells compared with fibroblasts; and five viruses showed selective replication on HNSCC cells compared with keratinocytes. Overall, CRAd-S.RGD with E1A driven by the survivin promoter and an infectivity-enhancing capsid modification showed the most favourable cytotoxicity pattern; being very potent in killing HNSCC cells, only slightly less effective than Ad5 in killing pre-neoplastic keratinocytes and the least toxic to normal keratinocytes.

A conditionally replicative adenovirus, CRAd-S-pK7, can target endometriosis with a cell-killing effect

BACKGROUND

Novel therapeutic approaches for endometriosis based on molecular strategies may prove to be useful. Conditionally replicative adenoviruses (CRAds) are designed to exploit key differences between target and normal cells. The wild-type adenovirus (Adwt) promoter can be replaced by tissue-specific promoters, allowing viral replication only in target cells. Viral infectivity can be enhanced by altering Ad tropism via fiber modification. We investigated whether CRAds can be used to target endometriosis and determined the most efficient transcriptional- and transductional-targeting strategy.

METHODS

An in vitro study was carried out using human endometriotic cell lines, 11Z (epithelial) and 22B (stromal), normal human ovarian surface epithelial cell line (NOSE006) and primary human endometriosis cells. A total of 9 promoters and 12 Ad tropism modifications were screened by means of a luciferase reporter assay. From this screening data, three CRAds (CRAd-S-pK7, CRAd-S-RGD, CRAd-S-F5/3sigma1, all incorporating the survivin promoter but with different fiber modifications) were selected to perform experiments using Adwt and a replication-deficient virus as controls. CRAds were constructed using a plasmid recombination system. Viral-binding capacity, rates of entry and DNA replication were evaluated by quantitative real-time PCR of viral genome copy. Cell-killing effects were determined by crystal violet staining and a cell viability assay for different concentrations of viral particles per cell.

RESULTS

Comparison of promoters demonstrated that the survivin promoter exhibited the highest induction in both endometriotic cell lines. Among the fiber-modified viruses, the polylysine modification (pK7) showed the best infection enhancement. CRAd-S-pK7 was validated as the optimal CRAd to target endometriosis in terms of binding ability, entry kinetics, DNA replication and cell-killing effect. CRAd-S-pK7 also exhibited a high level of DNA replication in primary endometriosis cells.

CONCLUSIONS

CRAd-S-pK7 has the best infection and cell-killing effect in the context of endometriosis. It could prove to be a useful novel method to target refractory cases of endometriosis.

Characterization of infectivity of knob-modified adenoviral vectors in glioma

Malignant glioma continues to be a major target for gene therapy and virotherapy due to its aggressive growth and the current lack of effective treatment. However, these approaches have been hampered by inefficient infection of glioma cells by viral vectors,particularly vectors derived from serotype 5 adenoviruses (Ad5). This results from limited cell surface expression of the primary adenovirus receptor, coxsackie-adenovirus-receptor (CAR), on tumor cells. To circumvent this problem, Ad fiber pseudotyping,the genetic replacement of either the entire fiber or fiber knob domain with its structural counterpart from another human Ad serotype that recognizes a cellular receptor other than CAR, has been shown to enhance Ad infectivity in a variety of tumor types,including human glioma. Here, we have extended the paradigm of genetic pseudotyping to include fiber domains from non-human or"xenotype" Ads for infectivity enhancement of human glioma cell populations. In this study, we evaluated the gene transfer efficiency of a panel of Ad vectors which express one of five different "xenotype"fiber knob domains, including those derived from murine,ovine, porcine and canine species, in both human glioma cell lines as well as primary glioma tumor cells from patients. Adenovirus vectors displaying either canine Ad or porcine Ad fiber elements had the highest gene transfer to both glioma cell lines and primary tumor cells. The correlation between the viral infectivity of modified adenovirus vectors and expression of human CAR and CD46(an adenovirus type B receptor) on the surfaces of tumor cells was also analyzed. Taken together, human adenovirus vectors modified with "xenotype" fiber elements could be excellent candidates to target human glioma.

Directing adenovirus across the blood–brain barrier via melanotransferrin (P97) transcytosis pathway in an in vitro model

Adenovirus serotype 5 (Ad5) is widely used in the development of gene therapy protocols. However, current gene therapy strategies involving brain are mostly based on intra-cranial injection. A major obstacle for systemically administered vectors to infect brain tissue is the blood-brain barrier (BBB). One strategy to cross the BBB is transcytosis, a transcellular transport process that shuttles a molecule from one side of the cell to the other side. Recently, melanotransferrin (MTf)/P97 was found to be able to cross the BBB and accumulate in brain. We thus hypothesize that re-directing Ad5 vectors to the MTf transcytosis pathway may facilitate Ad5 vectors to cross the BBB. To test this hypothesis, we constructed a bi-specific adaptor protein containing the extracellular domain of the coxsackie-adenovirus receptor (CAR) and the full-length melanotransferrin (sCAR-MTf), and investigated its ability to re-direct Ad5 vectors to the MTf transcytosis pathway. We found this adaptor protein could re-direct Ad5 to the MTf transcytosis pathway in an in vitro BBB model, and the transcytosed Ad5 viral particles retained their native infectivity. The sCAR-MTf-mediated Ad5 transcytosis was temperature- and dose dependent. In addition, we examined the directionality of sCAR-MTf-mediated Ad5 transcytosis, and found the efficiency of apical-to-basal transcytosis was much higher than that of basal-to-apical direction, supporting a role of this strategy in transporting Ad5 vectors towards the brain. Taken together, our study demonstrated that re-directing Ad5 to the MTf transcytosis pathway could facilitate gene delivery across the BBB.

Evaluation of tumor-specific promoter activities in melanoma

Gene therapy is a novel therapy for melanoma. To date, however, there is still no powerful tumor specific promoter (TSP) to restrict the transgene expression in melanoma cells. In order to define a useful TSP for targeting in the context of melanoma gene therapy, four promoters, the cyclooxygenase-2 (Cox-2), alpha-chemokine SDF-1 receptor (CXCR4), epithelial glycoprotein 2 (EGP-2), and survivin, were tested in both established melanoma cell lines and primary melanoma cells. We employed recombinant adenoviral vectors (reAds) each with a candidate TSP (the Cox-2, CXCR4, EGP-2, or survivin), a reporter luciferase gene, and a poly-A signal, all of which were inserted into the E1-deleted region. A reAdGL3Bcytomegalovirus (CMV), containing the CMV promoter and luciferase gene, was used as a positive control to normalize the luciferase activity. Luciferase activity was measured in multiple tumor cell lines and two primary melanoma cell cultures after infection with reAds. Human epithelial melanocytes, HEM, were used as normal control. In contrast to three other promoters, the survivin promoter exhibited the highest activities within both melanoma cell lines and primary melanoma cells, but not in HEMs. Additionally, the survivin promoter exhibited very low activities in major mouse organs including the liver, in vivo. EGP-2 is not active in melanoma; messenger RNA expressions were correlated to promoter activities both in melanoma cell lines and primary cell cultures. Thus, these data suggest that the survivin promoter achieved a 'tumor-on/liver-off' profile, and thus represents a potentially useful tumor-specific promoter with applications for transcriptional targeting of Ad vector-based cancer gene therapy or oncolysis to melanoma.

Transcriptional targeting of adenoviral vector through the CXCR4 tumor-specific promoter

Adenoviral vectors are considered to be good gene delivery vectors for cancer gene therapy due to their wide host tissue range and cell cycle-independent infectivity. However, the disadvantages include the lack of specificity for cancer cells and the high liver accumulation in vivo. The human CXCR4 gene is expressed at high levels in many types of cancers, but is repressed in the liver. We explored the CXCR4 promoter as a candidate to restrict adenoviral transgene expression to tumor cells with a low expression in host tissues. The luciferase activities in multiple cancer cell lines infected with recombinant adenovirus reAdGL3BCXCR4 or the control vector reAdGL3BCMV revealed that the CXCR4 promoter exhibited relatively high transcriptional activity in a breast cancer cell line, MDA-MB-361, and two ovarian cancer cell lines, OVCAR-3 and SKOV3. ip1, 65% (P=0.0087), 16.7% (P=0.1) and 20% (P=0.0079) compared to that of the CMV promoter, respectively, and low expression, 4.9 and 0.1%, respectively, in both normal cell lines HFBC and HMEC. In addition, CXCR4 had a low expression of luciferase (0.32%) compared to that of the CMV promoter in mouse liver in vivo. The data also revealed that the CXCR4 promoter was a stronger tumor-specific promoter (TSP) than the Cox-2M promoter in primary melanomas obtained from two patients. The CXCR4 promoter is shown to have a 'tumor-on' and 'liver-off' status in vitro and in vivo, and CXCR4 may prove to be a good candidate TSP for cancer gene therapy approaches for melanoma and breast cancers.

A novel type II complement C2 deficiency allele in an African-American family

A 9-yr-old African-American male presenting with severe recurrent pyogenic infections was found to have C2 deficiency (C2D). Analysis of his genomic DNA demonstrated that he carried one type I C2D allele associated with the HLA-A25, B18, DR15 haplotype. Screening all 18 exons of the C2 gene by exon-specific PCR/single-strand conformation polymorphism indicated abnormal bands in exons 3, 7, and 6, the latter apparently caused by the 28-bp deletion of the typical type I C2D allele. Nucleotide (nt) sequencing of the PCR-amplified exons 3 and 7 revealed a heterozygous G to A transition at nt 392, causing a C111Y mutation, and a heterozygous G to C transversion at nt 954, causing a E298D mutation and a polymorphic MaeII site. Cys111 is the invariable third half-cystine of the second complement control protein module of C2. Pulse-chase biosynthetic labeling experiments indicated that the C111Y mutant C2 was retained by transfected COS cells and secreted only in minimal amounts. Therefore, this mutation causes a type II C2D. In contrast, the E298D mutation affected neither the secretion of C2 from transfected cells nor its specific hemolytic activity. Analysis of genomic DNA from members of the patient's family indicated that 1) the proband as well as one of his sisters inherited the type I C2D allele from their father and the novel type II C2D allele from their mother; 2) the polymorphic MaeII site caused by the G954C transversion is associated with the type I C2D allele; and 3) the novel C111Y mutation is associated in this family with the haplotype HLA-A28, B58, DR12.

Susceptibility locus for IgA deficiency and common variable immunodeficiency in the HLA-DR3, -B8, -A1 haplotypes

BACKGROUND

A common genetic basis for IgA deficiency (IgAD) and common variable immunodeficiency (CVID) is suggested by their occurrence in members of the same family and the similarity of the underlying B cell differentiation defects. An association between IgAD/CVID and HLA alleles DR3, B8, and A1 has also been documented. In a search for the gene(s) in the major histocompatibility complex (MHC) that predispose to IgAD/CVID, we analyzed the extended MHC haplotypes present in a large family with 8 affected members.

MATERIALS AND METHODS

We examined the CVID proband, 72 immediate relatives, and 21 spouses, and determined their serum immunoglobulin concentrations. The MHC haplotype analysis of individual family members employed 21 allelic DNA and protein markers, including seven newly available microsatellite markers.

RESULTS

Forty-one (56%) of the 73 relatives by common descent were heterozygous and nine (12%) were homozygous for a fragment or the entire extended MHC haplotype designated haplotype 1 that included HLA- DR3, -C4A-0, -B8, and -A1. The remarkable prevalence of haplotype 1 was due in part to marital introduction into the family of 11 different copies of the haplotype, eight sharing 20 identical genotype markers between HLA-DR3 and HLA-B8, and three that contained fragments of haplotype 1.

CONCLUSION

Crossover events within the MHC indicated a susceptibility locus for IgAD/CVID between the class III markers D821/D823 and HLA-B8, a region populated by 21 genes that include tumor necrosis factor alpha and lymphotoxins alpha and beta. Inheritance of at least this fragment of haplotype 1 appears to be necessary for the development of IgAD/CVID in this family.

Molecular defects leading to human complement component C6 deficiency in an African-American family

Complement component C6 deficiency (C6D) was diagnosed in a 16-year-old African-American male with meningococcal meningitis. The patient's father and two brothers also had C6D, but gave no history of meningitis or other neisserial infection. By using exon-specific polymerase chain reaction (PCR)/single-strand conformation polymorphism as a screening step and nucleotide sequencing of target exons, we determined that the proband was a compound heterozygote for two C6 gene mutations. The first, 1195delC located in exon 7, is a novel mutation, while the second, 1936delG in exon 12, has been described before to cause C6D in an unrelated African-American individual. Both mutations result in premature termination codons and C6 null alleles. Allele-specific PCR indicated that the proband's two brothers also inherited the 1195delC mutation from their heterozygous mother and the 1936delG mutation from their homozygous father.

Evaluation of IgA deficiency in Sardinians indicates a susceptibility gene is encoded within the HLA class III region

IgA deficiency (IgA-D) has been associated with the HLA region, in particular with the North European haplotype HLA-A1, -B8, -DR3, but the exact location of the susceptibility gene(s) is unknown. Some reports suggest that a susceptibility gene is encoded in the class II region, while others implicate the class III region. We exploited differences between the common Sardinian and North European HLA-DR3 haplotypes to help localize the IgA-D susceptibility gene(s). With the knowledge that approximately 13% of HLA-DR3 homozygous individuals of North European origin are IgA-D, we examined 43 HLA-DR3 homozygous Sardinians to find that all had normal serum IgA, IgG and IgM levels. A detailed analysis of their MHC haplotypes indicated a common Sardinian HLA-DR3 haplotype TAP1A, TAP2A, HLA-DQB1*0201, -DQA1*0501, -DRB1*0301, LH1-(Z + 2), D3A-(Z + 2), C4B-0, C4A-L, G11-15, Bf-0-4, C2-a, HSP70-7.5, 9N3-(Z + 10), 82I-(Z - 2), TNFalpha-9, 62-(Z - 20), HLA-B18, -Cw5, -A30 which diverges from the common North European HLA-DR3 haplotype telomeric to the HLA-DR region. In parallel studies of five Sardinians with IgA-D, two of the 10 HLA haplotypes (20%) contained HLA-DR3, a frequency similar to that observed in the background population. One of these was the HLA-DR3- B8 North European haplotype, which occurs rarely in Sardinia. Our data favour the hypothesis that a class III region allele, present on the common North European but not on the Sardinian HLA-DR3 haplotype, confers susceptibility to IgA-D.

Age-related changes in serum immunoglobulins in patients with familial IgA deficiency and common variable immunodeficiency (CVID)

The concentration of serum immunoglobulins in individuals with IgA deficiency (IgAD) and CVID can vary with age to have practical implications for evaluation, therapy, and genetic analysis. Most IgAD and CVID patients in our clinic population in the Southeastern United States have inherited part or all of two extended MHC haplotypes, referred to as haplotype 1 (HLA-DQB1 0201, HLA-DR3, C4B-Sf, C4A-0, G1-15, Bf-0.4, C2-a, HSP-7.5, TNF alpha-5, HLA-B8, HLA-A1) and haplotype 2 (HLA-DQB1 0201, HLA-DR-7, C4B-S, C4A-L, G11-4.5, Bf-0.6, C2-b, HSP-9, TNF alpha-9, HLA-B44, HLA-A29). In the present study, the clinic records of 68 CVID patients and 73 IgAD patients were reviewed to determine whether patients with familial or MHC-associated IgAD or CVID experience changes in serum immunoglobulin concentrations. An increase in serum immunoglobulin to the normal range was associated with clinical improvement in one patient with CVID and haplotype 2, two patients with IgAD and haplotype 2, and one IgAD patient whose haplotype was not determined. Two patients with haplotype 1 and one with haplotype 2 had a significant decline in serum immunoglobulin: one progressed from normal to IgAD associated with IgG subclass deficiencies, and two progressed from IgAD to CVID. Five of the seven patients with notable changing serum immunoglobulin levels have a family member with either IgAD or CVID. The findings suggest that familial, MHC-associated IgAD and CVID may be either progressive or reversible disorders, and emphasize the value of monitoring immunoglobulin levels in affected individuals and their family members.

Genetic bases of human complement C7 deficiency

Complement C7 deficiency (C7D) is associated frequently with recurrent bacterial infections, especially meningitis caused by Neisseria meningitidis. We report in this work the molecular bases of C7D in two unrelated Japanese males. We used exon-specific PCR/single-strand conformation polymorphism analysis as a screening step for mutations. Subsequent direct sequencing of the target exons identified homozygous mutations in exon 16 of case 1 and in exon 15 of case 2. The mutation of case 1 was a homozygous T to A transversion at nucleotide 2250, the third nucleotide of the codon TGT for Cys728, leading to a stop codon TGA (C728X). In case 2, a homozygous 2-bp deletion (2137delTG/2138delGT/2139delTG) caused a frameshift, generating a premature termination codon 4 to 6 nucleotides downstream. Family study in case 1 confirmed the genetic nature of the defect. Moreover, we detected a novel polymorphism in intron 11 that presumably is linked to the mutation responsible for C7D in case 1. Our results indicate that the pathogenesis of C7D is heterogeneous like most of the other deficiencies of complement components.

Genetic bases of human complement C7 deficiency

Complement C7 deficiency (C7D) is associated frequently with recurrent bacterial infections, especially meningitis caused by Neisseria meningitidis. We report in this work the molecular bases of C7D in two unrelated Japanese males. We used exon-specific PCR/single-strand conformation polymorphism analysis as a screening step for mutations. Subsequent direct sequencing of the target exons identified homozygous mutations in exon 16 of case 1 and in exon 15 of case 2. The mutation of case 1 was a homozygous T to A transversion at nucleotide 2250, the third nucleotide of the codon TGT for Cys728, leading to a stop codon TGA (C728X). In case 2, a homozygous 2-bp deletion (2137delTG/2138delGT/2139delTG) caused a frameshift, generating a premature termination codon 4 to 6 nucleotides downstream. Family study in case 1 confirmed the genetic nature of the defect. Moreover, we detected a novel polymorphism in intron 11 that presumably is linked to the mutation responsible for C7D in case 1. Our results indicate that the pathogenesis of C7D is heterogeneous like most of the other deficiencies of complement components.

Molecular bases for inherited human complement component C6 deficiency in two unrelated individuals

Deficiency of the sixth component of complement (C6D) is frequently associated with recurrent neisserial infections, especially meningitis caused by Neisseria meningitidis. We here report the molecular bases of C6D in two unrelated subjects, one African American (case 1) and the other Japanese (case 2). Screening all 17 exons of the C6 gene and their boundaries by exon-specific PCR/single strand conformation polymorphism demonstrated aberrant single stranded DNA fragments in exon 12 of case 1 and exon 2 of case 2. Nucleotide sequencing of the amplified DNA fragments revealed a homozygous single-base deletion (G1936) in exon 12 case 1 and a heterozygous single base deletion (C291/C292/C293/C294) in exon 2 of case 2. Both mutations resulted in frame shifts and premature termination of the C6 polypeptide. Sequence-specific oligonucleotide probe hybridization and direct sequencing of exon 12 amplified from genomic DNA further supported the homozygosity of the mutation in case 1. Case 2 is apparently compound heterozygote, but the putative mutation in the other allele of the C6 gene remains unknown. Both case 1 and case 2 were homozygous for the C6A allotype. These data indicate that at least three distinct mutational events can cause C6D, single nucleotide deletions in exons 2 and 12, and a mutation yet unidentified. Thus, similar to other complement protein deficiencies, the pathogenesis of C6D appears to be heterogeneous.

Molecular bases for inherited human complement component C6 deficiency in two unrelated individuals

Deficiency of the sixth component of complement (C6D) is frequently associated with recurrent neisserial infections, especially meningitis caused by Neisseria meningitidis. We here report the molecular bases of C6D in two unrelated subjects, one African American (case 1) and the other Japanese (case 2). Screening all 17 exons of the C6 gene and their boundaries by exon-specific PCR/single strand conformation polymorphism demonstrated aberrant single stranded DNA fragments in exon 12 of case 1 and exon 2 of case 2. Nucleotide sequencing of the amplified DNA fragments revealed a homozygous single-base deletion (G1936) in exon 12 case 1 and a heterozygous single base deletion (C291/C292/C293/C294) in exon 2 of case 2. Both mutations resulted in frame shifts and premature termination of the C6 polypeptide. Sequence-specific oligonucleotide probe hybridization and direct sequencing of exon 12 amplified from genomic DNA further supported the homozygosity of the mutation in case 1. Case 2 is apparently compound heterozygote, but the putative mutation in the other allele of the C6 gene remains unknown. Both case 1 and case 2 were homozygous for the C6A allotype. These data indicate that at least three distinct mutational events can cause C6D, single nucleotide deletions in exons 2 and 12, and a mutation yet unidentified. Thus, similar to other complement protein deficiencies, the pathogenesis of C6D appears to be heterogeneous.

Ancestry of SINE-R.C2 a human-specific retroposon

We have reported previously that a retroposon, containing a variable number of tandemly repeated nucleotide sequences, is present in the third intron of the human C2 gene. This element, termed SINE-R.C2, is a member of a large retroposon family derived from the endogenous retrovirus HERV-K10 and estimated to include a few thousand copies per haploid human genome. In the present study we analyzed genomic DNA from 175 humans from several ethnic groups including Americans of European and African descent, Chinese, Africans, Australians, Pacific Islanders, Japanese, and Koreans. They all contained SINE-R.C2, as indicated by Southern blotting. However, SINE-R.C2 was absent from the genome of nonhuman primates, although SINE-R-type elements were present in chimpanzees and gorillas and the HERV-K10 genome was apparently present in all primates except for New World monkeys. These results indicate that HERV-K10 was inserted into the genome after the divergence of New World monkeys; the prototype SINE-R element, after divergence of orangutans; and SINE-R.C2, after the split between humans and chimpanzees.

Structure of the human C2 gene

A human genomic cosmid clone, S22A, was used to characterize the structure of the human C2 gene. Eighteen exons spanning 18 kb of DNA were mapped by nucleotide sequencing of exon-containing subclones and by Southern blotting. Introns vary in length between 83 bp and 4.4 kb and all intron/exon boundaries follow the AG/GT consensus rule for splicing. Exon 1 encodes 270 bp of the 5'-untranslated region of the C2 cDNA C2HL5-3 and 15 amino acids of the leader peptide. The three short consensus repeats of C2b are encoded by the single exons 2, 3, and 4, respectively. The von Willebrand factor type A-like domain of C2a is encoded by exons 6-10 and the serine protease domain by exons 11-18. Exons 5 and 15 appear to be unique to the C2 and factor B genes.

Structure of the human C2 gene

A human genomic cosmid clone, S22A, was used to characterize the structure of the human C2 gene. Eighteen exons spanning 18 kb of DNA were mapped by nucleotide sequencing of exon-containing subclones and by Southern blotting. Introns vary in length between 83 bp and 4.4 kb and all intron/exon boundaries follow the AG/GT consensus rule for splicing. Exon 1 encodes 270 bp of the 5'-untranslated region of the C2 cDNA C2HL5-3 and 15 amino acids of the leader peptide. The three short consensus repeats of C2b are encoded by the single exons 2, 3, and 4, respectively. The von Willebrand factor type A-like domain of C2a is encoded by exons 6-10 and the serine protease domain by exons 11-18. Exons 5 and 15 appear to be unique to the C2 and factor B genes.

Genetic and immunologic analysis of a family containing five patients with common-variable immune deficiency or selective IgA deficiency

A family with 13 members included 2 subjects with selective IgA deficiency (IgA-D) and 3 subjects with common-variable immune deficiency (CVID), diseases which usually occur sporadically. Reciprocal combinations of B and T cells in vitro between one normal and two immune-deficient family members and normal subjects revealed that defective Ig synthesis was determined by the B cells, while the patient T cells functioned normally. Normal T helper and suppressor function was demonstrated even in one patient with CVID who developed a T-cell lymphoproliferative disorder associated with elevated IgM; this patient's B cells made only IgM in vitro. Immune deficiencies were inherited in this family in a pattern consistent with an autosomal dominant trait with incomplete penetrance. All the immune-deficient patients in this family possessed at least one copy of an MHC haplotype previously shown to be abnormally frequent in IgA-D and CVID: HLA-DQB1*0201, HLA-DR3, C4B-Sf, C4A-deleted, G11-15, Bf-0.4, C2-a, HSP70-7.5, TNF alpha-5, HLA-B8, and HLA-A1. The patient who developed the lymphoproliferative disorder was homozygous for this haplotype. Four immunologically normal members, one of whom was 80 years old, also possessed this MHC haplotype, indicating that its presence is not sufficient for disease expression. A small segment of another MHC haplotype associated with Ig deficiency in the population also occurred in this family, but it was not associated with immune deficiency.(ABSTRACT TRUNCATED AT 250 WORDS)

Major histocompatibility complex class III genes and susceptibility to immunoglobulin A deficiency and common variable immunodeficiency

We have proposed that significant subsets of individuals with IgA deficiency (IgA-D) and common variable immunodeficiency (CVID) may represent polar ends of a clinical spectrum reflecting a single underlying genetic defect. This proposal was supported by our finding that individuals with these immunodeficiencies have in common a high incidence of C4A gene deletions and C2 rare gene alleles. Here we present our analysis of the MHC haplotypes of 12 IgA-D and 19 CVID individuals from 21 families and of 79 of their immediate relatives. MHC haplotypes were defined by analyzing polymorphic markers for 11 genes or their products between the HLA-DQB1 and the HLA-A genes. Five of the families investigated contained more than one immunodeficient individual and all of these included both IgA-D and CVID members. Analysis of the data indicated that a small number of MHC haplotypes were shared by the majority of immunodeficient individuals. At least one of two of these haplotypes was present in 24 of the 31 (77%) immunodeficient individuals. No differences in the distribution of these haplotypes were observed between IgA-D and CVID individuals. Detailed analysis of these haplotypes suggests that a susceptibility gene or genes for both immunodeficiencies are located within the class III region of the MHC, possibly between the C4B and C2 genes.

A variable number of tandem repeats locus within the human complement C2 gene is associated with a retroposon derived from a human endogenous retrovirus

We have previously described multiallelic restriction fragment length polymorphisms of the C2 gene, suggesting the presence of a variable number of tandem repeats (VNTR) locus. We report here the cloning and sequencing of the polymorphic fragments from the two most common alleles of the gene, a and b. The results confirm the presence of a VNTR locus consisting of a nucleotide sequence, 41 bp in average length, repeated tandemly 23 and 17 times in alleles a and b, respectively. The difference in the number of repeats between the two alleles is due to the deletion/insertion of two noncontiguous segments, 143 and 118 bp long, of allele a, and of a 40-bp segment of allele b. The VNTR region is associated with a SINE (short interspersed sequence)- type retroposon, SINE-R.C2, located within the third intron of the C2 gene. SINE-R.C2 is a member of a previously described large retroposon family of the human genome, apparently derived from the human endogenous retrovirus, (HERV) K10, which is homologous to the mouse mammary tumor virus.

Allelic associations of multiple RFLPs of the gene encoding complement protein C2

The gene for the second component of complement, C2, maps within the class III region of the major histocompatibility complex (MHC). Many human diseases have been reported to be associated with MHC alleles, haplotypes, or extended haplotypes, but in most cases additional polymorphic markers are needed for the eventual localization of the genes responsible for these diseases. In this study, nine C2 haplotypes for four restriction-site polymorphisms, detected by SstI, BamHI, and TaqI, were defined among 143 unrelated individuals. Two of these polymorphisms are multiallelic and map near the 5' end of the C2 gene. The extensive allelic variation of the C2 gene may prove of value in studies of diseases associated with the MHC.

Individuals with IgA deficiency and common variable immunodeficiency share polymorphisms of major histocompatibility complex class III genes

IgA deficiency and common variable immunodeficiency are heritable disorders that can occur within the same family. Both immunodeficiencies are characterized by arrests in B-cell differentiation that vary in the extent of the immunoglobulin isotypes involved. A high frequency of major histocompatibility complex supratypes associated with a null allele of the gene encoding the C4A isotype of complement component C4 has been observed in IgA-deficient individuals. In search of a genetic linkage between the two immunodeficiencies, we examined the major histocompatibility complex (MHC) class III genes encoding complement components C2, C4A, and C4B and steroid 21-hydroxylase in addition to the HLA serotypes in individuals with either common variable immunodeficiency or IgA deficiency. Twelve of 19 patients with common variable immunodeficiency (63%, P less than 0.001) and 9 of 16 patients with IgA deficiency (56%, P less than 0.01) had rare C2 alleles and/or C4A and 21-hydroxylase A deletions, whereas these gene features were seen in only 5 of 34 healthy individuals (15%) in the control group. Nine of 11 patients with C4A deletion had an HLA haplotype consistent with the MHC supratype HLA-A1, Cw7, B8, C4AQ0, C4B1, BfS, DR3 previously found to be associated with IgA deficiency. The data support the hypothesis that common variable immunodeficiency and IgA deficiency are related disorders, susceptibility to which is determined by a gene(s) within or near the MHC class III gene region on chromosome 6.