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Production and immunogenicity of multiple antigenic peptide (MAP) constructs derived from the S1 glycoprotein of infectious bronchitis virus (IBV).

Synthetic peptides were prepared as multiple antigenic peptide (MAP) constructs to the S1 glycoprotein of infectious bronchitis virus (IBV). The MAP system has been used in the production of anti-peptide and anti-protein antibodies. It has an advantage over linking peptides to a highly immunogenic carrier molecule because antibodies are not produced to the MAP core matrix of lysine residues. Two 25-residue peptides were synthesized to the Arkansas serotype and two were synthesized to the Massachusetts serotype of IBV. The peptide sequences correspond to amino acid residues 64 to 88 and to residues 117 to 141 for each of the IBV serotypes. A MAP construct for each peptide was prepared by linking 4 copies of a peptide to the immunogenetically inert core matrix of lysine residues. The MAP constructs were used to immunize specific pathogen free chickens. Anti-peptide ELISA titers and the dot immunobinding assay against the homologous peptide were positive for all of the sera tested whereas the anti-whole virus ELISA titers and virus neutralization titers were negative for all of the sera tested. Hyperimmune sera against whole virus did not cross react with synthetic peptides made to the heterologous virus suggesting a possible role for the MAP constructs in a serotype specific dot blot or ELISA test for IBV.

Amino Acid Sequence↗

Scleroderma overlap syndromes.

The most common scleroderma overlap syndromes are mixed connective tissue disease (MCTD), scleromyositis and synthetase syndrome. There is controversy concerning MCTD as a separate entity due to heterogeneous clinical manifestations, not infrequent transformation into definite CTD and various classification criteria. Our study of 94 adult patients and 20 children, classified according to the criteria of Alarcon-Segovia, and especially a 5, 9-year follow-up showed transformation into SLE or SSc in over 20% of patients, less frequently than reported by others, whereas over half of the cases remained undifferentiated CTD. In several cases ARA criteria for both SSc and SLE were fulfilled, and there is no consensus whether such cases should be recognized as coexistence of both definite diseases or as MCTD. High titers of U1 RNP antibodies to 70 kD epitope were invariably present, whereas, by transformation into distinctive CTD there appeared, in addition, antibodies characteristic of these CTD. Of 108 cases positive for PM-Scl antibody, 83% were associated with scleromyositis. This scleroderma overlap syndrome differed from MCTD by coexistent features of dermatomyositis (myalgia, myositis, Gottron sign, heliotrope rash, calcinosis) with no component of SLE, characteristic of MCTD. The course was also chronic and rather benign, as in MCTD, and all cases responded to low or moderate doses of corticosteroids. A not infrequent complication was deforming arthritis of the hands. Our immunogenetic study showed an association of cases positive for PM-Scl antibody with HLA-DQA1x0501 alleles in 100% and with HLA-DRB1x0301 in 94% of cases. Synthetase syndrome, associated with anti-histidyl-tRNA synthetase antibodies, studied in 29 patients with myositis and interstitial lung disease (ILD), only in single cases had scleroderma-like features. These cases differed from SSc by acute onset with fever, and by response to moderate doses of corticosteroids. We also studied overlap of localized scleroderma with other CTD: 21 cases of progressive facial hemiatrophy and linear scleroderma, and 55 (39.5%) of atrophoderma Pasini-Pierini (APP) and morphea. As in other autoimmune disorders, two or more connective tissue diseases (CTD) may develop concurrently or sequentially in the same patient. In such overlap syndromes ARA criteria must be fulfilled for each of the disease, and the clinical presentation has features of both. However more frequently overlap syndromes only combine some manifestations of more than one CTD, and present a highly heterogeneous group of disorders with prevailing clinical features of SSc.

Adolescent↗

Prevalence of IgM-, IgA- and IgG-rheumatoid factors in seronegative polyarticular disease compared to pauciarticular disease in juvenile chronic arthritis as measured by ELISA.

OBJECTIVE: To determine the prevalence of the rheumatoid factor isotypes measured by enzyme-linked immunosorbent assay (ELISA) in polyarticular and pauciarticular juvenile chronic arthritis (JCA), and evaluate the diagnostic test qualities. PATIENTS AND METHODS: 53 patients with JCA (20 with seronegative polyarticular disease at onset, 21 with pauciarticular onset and course of disease and 12 with extended pauciarticular disease), as well as 125 control children (58 healthy controls and 67 patients with other diseases) were tested. ELISA for the detection of IgM-, IgA- and IgG-isotypes of RFs was used. The diagnostic characteristics of the tests were evaluated by means of clinical epidemiology methods. RESULTS: The prevalence of the ELISA for IgG-, IgA-, and IgM-RF for JCA patients vs all controls at optimal cut-off titres was 13%, 29%, and 32%, respectively. The test for IgG-RF was established to be of no significance. IgA-RF had higher prevalence in the polyarticular and extended pauciarticular form, 40% and 33%, respectively. IgM-RF showed a prevalence of 55% for the polyarticular and 42% for the extended pauciarticular form. No significant prevalence has been found in the pauciarticular form. CONCLUSION: Our results indicate that ELISA for IgG-RF is of no diagnostic value for JCA. The ELISAs for IgM- and IgA-RFs demonstrated a diagnostic significance for the polyarticular and extended pauciarticular form. Juvenile chronic arthritis (JCA) is a heterogeneous disease which encompasses different forms defined by the type of onset. There is evidence, supported by immunogenetic studies that the various subgroups may represent distinct disease entities [1, 2]. Numerous immunological abnormalities have been detected in JCA, but the most characteristic serological findings are ANA and IgM-rheumatoid factor, thought to be useful in the classification of patients and their management. Antinuclear antibodies are universal in JCA, most commonly found in children with early onset pauciarthritis and late onset seropositive polyarthritis [1, 2, 3]. In contrast, the IgM-rheumatoid factor, measured by conventional agglutination techniques, is a hallmark only of polyarthritis with late onset resembling adult rheumatoid arthritis. This group of patients with "seropositive" disease represents less than 20% of all JCA children. Of those patients with "seronegative" disease 20-30% have a systemic onset and the remainder have either a pauciarticular or polyarticular form [2, 3]. Following the introduction of more sensitive techniques, it has already been established that rheumatoid arthritis (RA) patients' sera contain not only the "classical" 19S IgM-RF, but also other isotypes of the rheumatoid factor (RF). A number of studies have emphasized the presence of IgG-, IgA-, IgM- and even IgE- RF in patients with "seronegative" RA [4, 5, 6]. The aim of this study is to determine the prevalence of IgG, IgM and IgA RFs and to attempt at evaluating the diagnostic and prognostic qualities of the ELISA-tests for rheumatoid factor isotypes in polyarticular and pauciarticular forms at onset of JCA.

Arthritis, Juvenile↗

On the genetic heterogeneity of juvenile hyperglycemia.

We have briefly discussed immunogenetic studies of families with hyperglycemia which suggest the existence of at least four types of the disease: a) juvenile, insulin-dependent, ketosis prone diabetes determined by an autosomal recessive gene with 50% penetrance and in linkage with the HLA; b) juvenile, insulin-dependent, ketosis prone diabetes probably determined by an autosomal dominant gene; c) unidentified types of juvenile, insulin-dependent diabetes whose pathogenesis may be related to the HLA associations reported; and d) maturity onset type of hyperglycemia in the young, probably determined by an autosomal dominant gene. There are probably other forms of juvenile hyperglycemia. Some may depend on genes unrelated to the HLA, others may be mostly or totally environmental, rather than genetic.

Adolescent↗

Cardiotoxicity mechanisms from the point of view of preclinical or premarketing safety evaluation.

The most commonly occurring cardiotoxic reactions in humans are due to over-exposure to chemicals that affect physiological function of the heart. These effects, which are usually receptor-mediated, are dose related and can generally be predicted from safety studies in animals. Direct chemical toxicity is initiated by an interaction of a reactive metabolite of the xenobiotic with cellular macromolecules. The incidence of such cardiotoxicity is low because few of these chemicals are metabolized in the heart. The concentration of cellular protective substances influences the development of such toxicity, and therefore species variation should be considered in safety studies. Chemically induced immune system-mediated reactions can develop in the heart, and may occur in anaphylaxis. Antibody mediated cytotoxic or immune complex reactions are rare events, and the predictability is poor. In some instances sensitivity is immunogenetically controlled. Cardiotoxic effects can also develop after prenatal exposure to chemicals, and thus consideration should be given to examining the offspring for those effects in teratology studies.

Adaptation, Physiological↗

Clinical and laboratory features of patients with scleroderma and silicone implants.

We reviewed the available clinical and laboratory data from 56 patients with scleroderma and silicone implants from the English medical literature and 19 cases which have not been previously reported. The average age of onset of scleroderma was 43.6 +/- 10 years (range 20-73). Patients had silicone implants for an average of 9 +/- 4 years prior to the development of scleroderma (range 1-32). Most patients had limited scleroderma (41%). Twenty three percent had intermediate scleroderma and 36% had diffuse scleroderma. Clinical findings included: Raynaud's phenomenon in 77%, esophageal dysfunction in 53%, and pulmonary involvement in 47%. Cardiac and renal involvement were uncommon. Antinuclear antibodies by immunofluorescence were found in 83 percent of patients. The immunofluorescence pattern was speckled in 53%, centromere in 31% and nucleolar in 9%. Other antibodies (Scl-70, RNP, SSA/Ro, PM-Scl) were found in only a small proportion of patients. A clinical, serologic and immunogenetic comparison of patients with silicone implants and scleroderma and patients with idiopathic scleroderma is needed to better understand the pathogenesis of this disorder.

Adult↗

HTLV-1-mediated immunopathological CNS disease.

HAM/TSP is a chronic inflammatory disease of the spinal cord. It is rather rare in HTLV-1-infected individuals. Immunogenetic factors of the HLA complex have been identified that support or prevent the development of the disease. In HAM/TSP patients a characteristic constellation of high proviral loads and increased cellular and humoral immune responses have been established. Immune dysfunction in HAM/TSP patients might be partly explained by HTLV-1 tax p40 transactivation of cellular genes in infected CD4+ T lymphocytes. The oligoclonal expansion of infected T lymphocytes, the variation of tax p40 within HTLV-1 carriers, and the regulation of proviral gene expression are possible determinants for disease development and need to be clarified in future studies.

CD4-Positive T-Lymphocytes↗

Historical perspective of genetic research with nonhuman primates.

Genetics became firmly established as a scientific discipline early in the twentieth century, but major genetic research programs that involve nonhuman primates have been initiated only in the last two decades. Considerable activity in this area has been stimulated by the concurrent development of powerful techniques for detecting variability in chromosomes, proteins, and DNA; the establishment of pedigreed breeding colonies; and the recognition that nonhuman primates are ideally suited as models of human disease and social structure. The subdisciplines of cytogenetics, immunogenetics, and biochemical genetics have established a firm basis for biomedical and evolutionary research with nonhuman primates, and they will contribute greatly to future research initiatives. More recently, the advent of molecular genetics has enhanced the opportunities for research; and the exploration of nonhuman primates as potential models for genetically mediated diseases has been richly rewarded. We stand at the threshold of a new and exciting era in genetic research with nonhuman primates. The results of research programs already underway not only will provide more definitive answers about the origin of man, but also will play a critical role in solving the health-related problems of the present and of the future.

Animals↗

Use of monoclonal antibodies in genetic research with nonhuman primates.

Monoclonal antibodies, because of their specificity and unlimited availability, have become one of the most powerful experimental tools available to the biological sciences. It is possible to make monoclonal antibodies that bind to determinants that are monomorphic in one or more species or to determinants that are polymorphic within a species. Few monoclonal antibodies have been made using immunogens derived from nonhuman primates. However, some monoclonal antibodies that recognize monotypic markers in humans can be used to detect polymorphic markers in nonhuman primates. Thus, the rapid development of monoclonal antibodies specific for human proteins significantly increases the potential number of immunogenetic markers useful for studying phylogenetic relationships and for identifying genetic polymorphisms among nonhuman primates.

Animals↗

Cloning and characterization of class I Mhc genes of the zebrafish, Brachydanio rerio.

The zebrafish (Brachydanio rerio) offers many advantages for immunological and immunogenetic research and has the potential for becoming one of the most important nonmammalian vertebrate research models. With this in mind, we initiated a systematic study of the zebrafish major histocompatibility complex (Mhc) genes. In this report, we describe the cloning and characteristics of the zebrafish class I A genes coding for the alpha chains of the alpha beta heterodimer and thus complete the identification of all four classes and subclasses of the Mhc in this species. We describe the full class I alpha cDNA sequence as well as the exon-intron organization of the class I A genes, including intron sequences. We identify three families of class I A genes which we designate Brre-UAA, -UBA, and -UCA. The three families originated about the time of the divergence of cyprinid and salmonid fishes. All three families are members of an ancient lineage that diverged from another, older lineage also represented in cyprinid fishes before the radiation of teleost orders. The fish class I A genes therefore evolve differently from mammalian class I A genes, in which the establishment of lineages and families mostly postdates the divergence of orders.

Amino Acid Sequence↗

A genetic analysis of human minor histocompatibility antigens demonstrates Mendelian segregation independent of HLA.

An analysis of the genetic traits of human minor histocompatibility (mH) antigens is, unlike with inbred mice, rather complicated. Moreover, the fact that mH antigens are recognized in the context of MHC molecules creates an additional complication for reliable segregation analysis. To gain insight into the mode of inheritance of the mH antigens, we relied upon a series of HLA-A2-restricted cytotoxic T-cell (CTL) clones specific for four mH antigens. To perform segregation analysis independent of HLA-A2, we transfected HLA-A2-negative cells with the HLA-A2 gene: this results in the cell surface expression of the HLA-A2 gene product and, if present, mH antigen recognition. The mode of inheritance of the HLA-A2-restricted mH antigens HA-1, -2, -4, and -5 was analyzed in 25 families whose members either naturally expressed HLA-A2 or were experimentally rendered HLA-A2-positive. Analysis of distribution of the mH antigens in the parent population among the mating types, together with their inheritance patterns in the families, demonstrated that the four mH antigens behaved as Mendelian traits, whereby each can be considered a product of a gene with two alleles, one expressing and one not expressing the detected specificity. We also showed that the loci encoding the HA-1 and HA-2 antigens are not closely linked to HLA (lod scores Z (0 = 0.05) <-4.0). Some indication was obtained that the HA-4- and HA-5-encoding loci may be closely linked to HLA. While we are aware of the limited results of this nonetheless comprehensive study, we feel the similarity in immunogenetic traits between human and mouse mH antigens is at least striking.

Alleles↗

Immunoglobulin allotypes in Ecuadorian Cayapa Indians.

Indigenous Indian groups comprise approximately 20% of Ecuador's population, the third largest percentage in all of Central or South America, yet immunogenetic data on these groups are lacking in the literature. In the course of population migration studies, sera collected from 65 Ecuadorians living in the northern province of Esmeraldas were typed for six GM and two KM markers. The study population consisted of 47 Cayapa Indians and 18 blacks of African origin, descendants of slaves imported into the area during the seventeenth century. The Cayapa demonstrated three GM phenotypes, two of which are common to other South American Indian tribes. The frequency of KM1 positive Cayapa Indians (63%) is similar to other South American Indian tribes, but is significantly greater than the Huaorani of eastern Ecuador (2%), the only other Ecuadorian Indian group for whom limited immunoglobulin allotype data are available (chi 2 = 35.8, P < 0.0001).

Black People↗

HLA-D gene studies in relation to immune responsiveness to a grass allergen Lol p III.

The grass pollen allergen Lol p III (Mr 11,000) is a well-characterized antigen that has been found useful in immunogenetic studies of human immune responsiveness. Since immune responsiveness to this allergen is associated with HLA-DR3, we investigated whether there was any sequence in the HLA-D region that would render a person "susceptible" [antibody (Ab)-positive] to the allergen. By sequence-specific oligonucleotide (SSO) slot-blot and sequence analyses of polymerase chain reaction (PCR)-amplified genomic DNA from Lol p III responder and nonresponder subjects, Ab responsiveness was found to be strongly associated with the sequence Glu-Tyr-Ser-Thr-Ser (EYSTS), present in the first polymorphic regions of DR beta I polypeptide chains of DR3, DR11 (split of DR5), and DRw6. Of the 41 grass-allergic subjects investigated, 19 had the EYSTS sequence, of whom 18 (95%) were Lol p III immunoglobulin G (IgG) Ab responders; among the 22 EYSTS- subjects, ten were Lol p III responders (P = 0.001, relative risk = 21.6). No such association was found with any polymorphic sequences in other DR beta chains, or in DQ alpha I and DQ beta I chains. These findings suggest that the EYSTS sequence is important in the presentation of an epitope of Lol p III; other sequence(s) may be involved in the presentation of other epitope(s). To our knowledge, this is the first demonstration of a strong association between a specific HLA sequence and immune responsiveness to a well-defined antigen. The paper shows that presence of the EYSTS sequence classifies subjects as Lol p III responders in 18/19 cases.

Allergens↗

Genetic analysis of the Mls system. Formal Mls typing of the commonly used inbred strains.

In order to elucidate the biological role of minor lymphocyte stimulating (Mls) gene products, we have been investigating the fundamental immunogenetic characteristics of the Mls system. In this report, we describe the distribution of stimulatory Mls products, Mlsa and Mlsc, in a panel of laboratory inbred strains based on the response pattern of H-2-compatible naive T-cell populations as well as monospecific Mlsa- or Mlsc-reactive T-cell clones. In addition, the expression of four different T-cell receptor (Tcr) b-V segment Tcrb-V3, -V6, -V8.1, and -V9, which were recently reported to be associated with T-cell recognition of Mls gene products in these strains, was examined. The results indicate that the majority of commonly used laboratory strains including those originally typed as Mlsa are also expressing Mlsc determinants and that very few independent inbred strains are non-Mlsc. Moreover, the pattern of Tcrb-V expression in spleen as well as in thymus suggests that the association between Mls expression and clonal deletion of self Mls-reactive T cells appears to be the general rule in inbred strains. Based on these results, implications for the nondetectable Mls-like gene products in other species besides the mouse are discussed.

Animals↗

Survival and immunogenicity of dissociated allogeneic fetal neural dopamine-rich grafts when implanted into the brains of adult mice.

The survival of grafts of dissociated allogeneic fetal neural dopamine (DA) rich tissue in the striatum has been studied after transplantation between inbred strains of mice differing at defined immunogenetical loci between donor and recipient. Six to 7 weeks and 15 weeks after grafting, surviving grafted DA neurons were found in the brains of all the recipients, albeit with a large variation in numbers, located either within the striatum or within the adjacent lateral ventricle. The mean number of surviving DA neurons did not differ between the syngeneic controls and the histoincompatible donor-host combinations, and there was no difference in survival between grafts that differed at single or multiple major histocompatibility complex (MHC) loci, and those that differed at multiple non-MHC loci. The amount of inflammatory cells in the graft area did not differ between the groups, and none of the animals showed massive infiltration of inflammatory cells. The in situ immunogenicity of the grafted neural tissue after intracerebral implantation was monitored by means of Simonsen's alloimmunization test, at 6-7 weeks after transplantation, which provides a sensitive measure primarily of the cellular immunological response. Most, but not all, graft recipients showed immunization with a Spleen Index (S.I.) close to that seen in recipients of an orthotopical skin graft of the same histoincompatibility combination. In contrast to the prolonged survival of the intracerebral neural transplants, none of the skin grafts survived longer than 3 weeks, thus demonstrating the immunologically privileged status of the brain. We conclude that intracerebrally grafted allogeneic neural tissue is capable of provoking a cellular immune response. Despite host immunization, however, the dissociated fetal neural allografts survived for at least 15 weeks without any overt signs of rejection, regardless of the donor-host combination used.

Animals↗

Enhanced interferon-gamma production by lymphocytes induced by a mitogen from mycoplasma arthritidis in patients with ankylosing spondylitis.

We have examined proliferation of and interferon-gamma (IFN-gamma) production by peripheral blood lymphocytes induced by a purified mitogen derived from mycoplasma arthritidis (MAS) in patients with seronegative spondylo-arthropathies and healthy individuals. In all patients and healthy controls MAS exerted a potent nonspecific lymphoproliferation. In contrast, only patients with ankylosing spondylitis (ASp) showed a strong IFN-gamma production after stimulation with MAS. The maximal IFN-gamma response was observed in HLA-B27+/HLA-DQw3+ patients. However, healthy controls with the HLA-DQw3 haplotype with or without the presence of HLA-B27 exhibited also a slight but statistically not significant increase of IFN-gamma production. Moreover, in this study we have found an enhanced frequency of HLA-DQw3 in patients with ASp and reactive arthritis. This immunogenetic association explains the enhanced lymphocyte reactivity in these inflammatory rheumatic disorders to mycoplasmal antigens.

Antigens, Bacterial↗

Lack of linkage between gene(s) controlling the synthesis of the seventh component of complement and the HLA region on chromosome No. 6 in man.

The family of an individual was studied who lacks the seventh component of complement in his serum (C7 homozygous deficiency). Both parents are C7 heterozygous-deficient. In this investigation, the following parameters were determined: complement components in functional and immunochemical tests; HLA-A,B antigens, HLA-D (MLC) determinants; the Bf system; glyoxalase I and B cell antigens. No evidence for linkage between the immunogenetic linkage group on chromosome 6 and gene(s) controlling the synthesis of the seventh component of complement was obtained. This is in according with the assumption that only genes controlling components of the initiating rather than the membrane attack unit of complement are linked to the HLA region.

Child↗

The HLA system and leprosy in Thailand.

To investigate immunogenetics of leprosy, 205 leprosy patients (26 with tuberculoid, 57 with borderline-tuberculoid, 21 with borderline, 31 with borderline-lepromatous, and 70 with lepromatous leprosy) have been typed for HLA antigens, and compared with 183 healthy controls from the same region (Northern Thailand). There was no significant difference between the overall group of leprosy patients or the three borderline classes and the controls. The two polar forms, tuberculoid and lepromatous leprosy, however, showed significant associations: HLA-A2 is decreased and HLA-Bw17 is increased in tuberculoid leprosy; HLA-B7 is increased in lepromatous leprosy. When both polar forms are compared with each other, HLA-A2 is significantly higher, HLA-Bw40 lower in patients with lepromatous than in those with tuberculoid leprosy. The results are discussed with respect to the different immune responsiveness in the two polar forms of leprosy.

Female↗