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Biomedical subjects

J J Hooks

Publications and source records attributed to J J Hooks.

89 records · Page 5Linked to original sources

Interferon-induced enhancement of IgE-mediated histamine release from human basophils requires RNA synthesis.

Incubation of human leukocytes with certain viruses results in the enhancement of IgE-mediated release of histamine. This enhancement is produced by interferon. The present experiments show that an induction period of 6 to 9 hr and new RNA synthesis are required for interferon to enhance histamine release. This points to the possibility that interferon may exert its antiviral and histamine-release enhancing activities by acting through a common pathway.

Allergens↗

Possibility of a viral etiology in recurrent aphthous ulcers and Behçet's syndrome.

The clinical signs, laboratory data, and histological features of recurrent aphthous ulcers (RAU) and Behçet's syndrome suggest a viral etiology. In fact, there are reports of adenovirus isolations in herpetiform oral ulcers and on the isolation of a filterable agent in sporadic cases of Behçet's syndrome. However, isolation studies on the major and minor aphthous ulcers and more recent studies on Behçet's syndrome have been negative. A review of the literature on the role of viruses and autoimmunity in RAU and Behçet's syndrome is presented. Biopsy specimens of ulcerative lesions were grown in vitro for up to 300 days. Those cultures, along with leukocytes and body fluids, were examined by a variety of techniques for the presence of virus or viral antigens. Although a persistent or latent virus was not detected, these negative studies cannot exclude a viral etiology. In fact, the hypothesis of an infectious and viral etiology is still reasonable.

Antibodies, Viral↗

Persistent shedding of adenovirus in urine of chimpanzees.

A new adenovirus, designated Pan 11, was isolated repeatedly from the urine of several chimpanzees for more than 1 year. One chimpanzee had chronic interstitial nephritis; the others were healthy. Most chimpanzees tested had neutralizing antibodies to Pan 11 virus in the serum; three people who worked with chimpanzees also acquired antibodies. Transplantable rhabdomyosarcomas developed in hamsters inoculated as newborns with Pan 11 virus.

Adenoviridae↗

Pelvic endometriosis and simian foamy virus infection in a pigtailed macaque.

Pelvic endometriosis and simian foamy virus infection occurred in a pigtailed macaque. Diffuse omental, peritoneal, and intestinal implantation of endometrium resulted in massive adhesions between adjacent abdominal and pelvic viscera, with formation of a large mass in the right caudal quadrant of the abdomen. Simian foamy virus type 1 was isolated from ectopic endometrium and from the uterine wall but was considered to be merely epiphenomenal.

Animals↗

Enhancement of IgE-mediated histamine release from human basophils by viruses: role of interferon.

Human leukocytes maintained in culture are induced to release histamine when exposed to ragweed antigen E or anti-IgE. Leukocyte cultures incubated with virus (i.e. HSV-1, Influenza A, and Adeno-1) but not exposed to ragweed antigen E or anti-IgE fail to release histamine. If, however, leukocyte cultures are first exposed to virus and then to ragweed antigen E or anti-IgE, significant enhancement of histamine release occurs. Both infectious and inactivated virus enhance histamine release and the degree of enhancement is related to the concentration of virus and the length of the incubation. Tissue culture fluid harvested 8 h after exposure of leukocytes to virus contains a soluble factor which is capable of enhancing histamine release when added to fresh leukocyte cultures. This factor has all the properties of interferon including species specificity and cannot be dissociated from the antiviral activity of interferon. Moreover, both known inducers of interferon (poly I:poly C) and standard preparations of interferon are capable of enhancing histamine release. The enhancement of histamine release by interferon represents a new biological role for interferon.

Adenoviridae↗

Possible role of infectious simian foamy virus DNA in persistent infection.

Simian foamy virus type 7 (SFV-7) can persist in peripheral blood leukocytes of SFV-7-infected rabbits. Rabbit peripheral blood leukoyctes cultured in vitro did not support the growth of SFV-7, but low titer of virus could be detected after 4 to 5 days incubation. The DNA derived from SFV-7 infected primary rabbit kidney cells is infectious. The presence of SFV-7 DNA provirus in infected rabbit kidney cells during replication may contribute one of the mechanisms of persistance.

Animals↗

Viral spread in the presence of neutralizing antibody: mechanisms of persistence in foamy virus infection.

Several viruses were categorized on the basis of their ability to spread from cell to contiguous cell and form plaques in the presence of antiviral antibody. Herpes simplex virus, cytomegalovirus, and vaccinia, measles, and foamy viruses were able to spread in the presence of neutralizing antibody, whereas coxsackievirus, encephalomyocarditis virus, vesicular stomatitis virus, mumps virus, and simian virus 5 failed to spread. A detailed study of one of these virus groups (simian foamy viruses) suggested that the ability of these viruses to spread from cell to cell in the presence of antiviral antibody, the failure of antiviral antibody and complement to lyse infected cells, and the poor induction and relative resistance of these viruses to the antiviral action of interferon contribute to the persistent nature of this infection.

Antibodies, Viral↗

Production of interferon by immune lymphocytes exposed to herpes simplex virus-antibody complexes.

Splenic leukocytes from rabbits immunized with herpes simplex virus (HSV) incorporated significant amounts of 3H-TdR and produced interferon after in vitro incubation with HSV antigens. In contrast, splenic leukocytes from nonimmune rabbits did not incorporate 3H-TdR or produce interferon when incubated with HSV antigens. Antigen-antibody complexes consisting of HSV antigens and anti-HSV antibody also were capable of stimulating immune leukocytes to incorporate 3H-TdR and to produce interferon.

Animals↗

Isolation of a new simian foamy virus from a spider monkey brain culture.

A syncytium-forming (foamy) virus was isolated from a spider monkey brain cell culture. Cytopathic effect was observed both in the brain culture and in human embryonic kidney cells. Neutralizing antibody was present in the sera of the spider monkey from whom the isolation was made. The virus was inhibited by 5-bromo-2-deoxyuridine (20 mug/ml), contained a ribonucleic acid-dependent deoxyribonucleic acid polymerase, and had an infectivity peak at 1.15 g/cm(3) in a sucrose density gradient. The virus passed through a 220-nm but not a 100-nm membrane filter, was chloroform sensitive, and was inactivated at 56 C in 30 min. Hemagglutinating and hemadsorption activity was not noted with a variety of erythrocytes. The virion was spherical, formed in the cytoplasm, and was 105 to 115 nm in diameter. Ring-shaped nucleoids, 45 to 50 nm in diameter, were associated with tubular profiles. The virus was not neutralized by sera prepared against known viruses, including simian foamy virus types 1 through 7, Mason-Pfizer monkey virus, and bovine syncytial and measles viruses. Sera from a rabbit hyperimmunized with the isolate and sera from 19 spider monkeys had neutralizing antibody to the isolate; however, these sera did not cross-react with simian foamy virus types 1 through 7. Neutralizing antibody to the isolate was not detected in sera from 16 humans, 9 rhesus monkeys, and 10 chimpanzees.

Animals↗

Circulating interferon in human autoimmune diseases.

In summary, IFN is found in the circulation of patients with certain autoimmune diseases. Moreover, the presence of IFN in SLE patients correlate with immunologic and clinical disease activity. Characterization of IFN shows that it is a leukocyte product and may consist of subtypes of IFN-alpha or a mixture of alpha and gamma IFN. The exact role of IFN in the pathogenesis of human autoimmune disorders remains unknown. However, since IFN is an immunoregulatory protein, it is possible that it may modify immune functions in these patients.

Autoimmune Diseases↗

Detection of anti-interferon antibodies in systemic lupus erythematosus.

In this study, we show that sera from 2 of 13 patients with clinically active systemic lupus erythematosus (SLE) contained anti-interferon alpha (anti-IFN alpha) antibody. In contrast, anti-IFN alpha activity was not detected in sera from patients with clinically inactive SLE, rheumatoid arthritis (RA), Sjögren's syndrome, or in normal individuals. None of the sera exhibited anti-IFN gamma activity. These studies show that anti-IFN antibody, like IFN itself, is most frequently observed in patients with clinically active SLE. It is also possible that the presence of IFN-anti-IFN complexes may contribute, in part, to the pathogenesis of this disease.

Adolescent↗

Diminished peripheral blood monocyte DR antigen expression in systemic lupus erythematosus.

We have studied DR expression on peripheral blood adherent cells, that consist of greater than 95% nonspecific esterase positive monocytes, of 50 systemic lupus erythematosus (SLE) patients. DR expression was determined using anti-DR antibody and complement mediated cytotoxicity. DR expression by SLE cells was significantly less than normal (p less than 0.001). There was no significant correlation between diminished DR expression and clinical activity or steroid treatment of the SLE patients. The DR expression on monocytes from seven patients that had elevated serum interferon levels was either in the normal range or above normal. DR expression by unstimulated SLE monocytes incubated for 3 days in vitro spontaneously decreased to 23 +/- 4% which was comparable to 31 +/- 4% for controls. The addition of interferon containing concanavalin A stimulated mononuclear cell culture supernatant (Con A sup) only partially prevented this decrease and yielded 49 +/- 7% DR+ SLE monocytes as compared with 69 +/- 6% DR+ control monocytes after 3 days of incubation (P less than 0.02). Addition of indomethacin to cells incubated with Con A sup did not significantly increase SLE monocyte DR expression, suggesting that prostaglandins did not play an important role in reducing in vitro DR expression by SLE cells. The reasons for the depressed SLE adherent cell DR expression remain unclear, as well its possible affect on immune responses. Further study of SLE monocytes may provide clues to understanding the disease.

Adolescent↗