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Biomedical subjects

G J Stanton

Publications and source records attributed to G J Stanton.

At least 55 records · Page 3Linked to original sources
PubMed1982

Neutralization of native human gamma interferon (HuIFN gamma) by antibodies to a synthetic peptide encoded by the 5' end of HuIFN gamma cDNA.

A synthetic peptide corresponding to the N-terminal amino acid sequence of human gamma-interferon (HuIFN gamma), based on the cDNA sequence, was used to produce antibodies in rabbits that were reactive with native HuIFN gamma. Antibodies from all immunized rabbits neutralized the antiviral activity of HuIFN gamma. Significant neutralization of other HuIFN and mouse IFN was not observed. The peptide had the sequence Cys-Tyr-Cys-Gln-Asp-Pro-Tyr-Val-Lys-Glu-Ala-Glu-Asn-Leu-Lys-Lys-Tyr-Phe-Asn-Ala ,and was coupled to keyhole limpet hemocyanin by disulfide linkage with the use of cystamine. The specificity of the antibodies produced to the peptide was compared to that of antibodies produced to native HuIFN gamma by neutralization of HuIFN gamma and by reactivity with peptide in the enzyme-linked immunosorbent assay (ELISA). The ratio of anti-peptide antibody neutralization of HuIFN gamma vs reactivity with peptide in the ELISA was at least 28-fold lower than for anti-HuIFN gamma antibody. Thus the antibodies to peptide and to HuIFN gamma were directed primarily against different determinants on native HuIFN gamma or the anti-HuIFN gamma antiserum probably contained antibodies to additional determinants. The anti-peptide antibodies should be useful for further characterization and purification of HuIFN gamma.

Amino Acid Sequence↗
PubMed1982

Characterization of a soluble suppressor of human B cell function produced by a continuous human suppressor T cell line. II. Evidence for suppression through a direct action of CTC-SISS-B on human B cells.

CTC-SISS-B is an antigen-nonspecific suppressive lymphokine elaborated by an interleukin 2-dependent suppressor T cell line that produces noncytotoxic inhibition of human B cell but not T cell function. Like SISS-B, a soluble suppressive lymphokine present in the supernatants of Con A-activated peripheral blood T cell cultures, CTC-SISS-B is of 60,000 to 90,000 m.w., and its action is blocked by the simple sugar L-rhamnose. CTC-SISS-B inhibits human B cell Ig production and proliferation through a direct interaction with human B cells rather than through indirect effects on immunoregulatory T cells or monocytes. CTC-SISS-B suppression occurs through inhibition of an early event(s) in B cell activation since proliferation and Ig production by established human B cell lines are not inhibited by this lymphokine. Despite sharing many biochemical and biologic properties, CTC-SISS-B and gamma-interferon appear to be distinct mediators.

B-Lymphocytes↗
PubMed1981

Inactivation of poliovirus by chloramine-T.

Since concern has recently been expressed about the presence of genotoxic substances due to chlorination of water and wastewater, chloramine-T (CAT) is proposed as an alternative disinfectant to chlorine. The viricidal properties of chlorine and CAT were compared. Kinetics of inactivation of poliovirus type 2 by chlorine and CAT in chlorine demand-free water were investigated by using a kinetic apparatus. Inactivation of the virus by chlorine and CAT occurred in two steps. The initial linear part of the inactivation curve followed a pseudo-first-order reaction with the virus. An obvious dose-response relationship was demonstrated with CAT. The rate of inactivation of the virus by CAT was faster in acid medium than in alkaline medium. Inactivation kinetic studies were performed at different temperatures, and the kinetic, Arrhenius, and thermodynamic parameters were evaluated. The rate of inactivation of poliovirus type 2 by chlorine was faster than that by CAT under identical conditions. A mechanism for the viral inactivation in acid conditions was proposed which led to a rate equation consistent with the experimental results. The results indicate that CAT may be an effective viricide against poliovirus type 2 in an acid medium.

Chloramines↗
PubMed1981

Human B lymphocytes produce leukocyte interferon after interaction with foreign cells.

Enriched human B-cell populations cocultivated with xenogeneic or allogeneic tumor cells produced 1,000 to 10,000 U of leukocyte interferon per ml. In contrast, cocultivation of enriched plastic-adherent or T-cell populations with xenogeneic or allogeneic cells produced only 10 to 30 U of interferon. The population of cells producing the interferon absorbed to nylon wool and not sheep erythrocytes. They showed a strong mitogenic response to the B-cell mitogen Escherichia coli lipopolysaccharide but not the T-cell mitogen staphylococcal enterotoxin A. In addition, treatment of this cell population with goat anti-human immunoglobulin M and complement depleted the cell population synthesizing the interferon. Together, these in vitro findings strongly suggest that the cells producing most of the interferon after interacting with foreign cells belong to the B-cell population. These results also suggest that the cells that produce most of the leukocyte interferon after interacting in vivo with tumors or other cells made foreign to the body by certain viruses most likely belong to the B-lymphocyte population.

Animals↗
PubMed1981

Antibody to staphylococcal enterotoxin A-induced human immune interferon (IFN gamma).

Antiserum to human gamma interferon (IFN gamma) was produced in rabbits immunized with partially purified (10(4.8) to 10(6.2) antiviral U/mg protein) staphylococcal enterotoxin A-induced IFN gamma. Staphylococcal enterotoxins, phytohemagglutinin M, concanavalin A, and pokeweed mitogen-induced antiviral activity in human leukocyte cultures was neutralized to undetectable levels by the antiserum. However, human leukocyte interferon (IFN alpha), human fibroblast interferon (IFN beta), and mouse interferons were not neutralized by the antiserum. After determining the antiserum was specific for IFN gamma and did not neutralize other known types of interferon, it was used with antibody to human IFN alpha to demonstrate the type(s) of interferon stimulated by some new inducers and antigens. Galactose oxidase- and calcium ionophore-induced interferons were neutralized to undetectable levels by the antiserum to IFN gamma. Interferon produced in leukocyte cultures from tuberculin-negative individuals stimulated with tuberculin-purified protein derivative or old tuberculin was IFN alpha, whereas interferon from tuberculin-positive individuals was a combination of alpha and gamma IFN. In addition, the antiserum neutralized the anticellular and natural killer cell enhancement activities of IFN gamma preparations. The specificity of this antiserum for IFN gamma indicates that it is an additional, powerful tool for identifying and classifying known and new interferons produced in vitro or in vivo and for investigating the role(s) of IFN gamma during the course of infectious, neoplastic, and autoimmune diseases.

Animals↗
PubMed1980

Transfer of interferon-induced viral resistance from human leukocytes to other cell types.

Nonsensitized human leukocytes cocultured with various xenogeneic epithelioid and fibroblastic cells produced human leukocyte interferon and shortly thereafter transferred antiviral activity to the xenogeneic cells. Antiviral activity in the cocultured xenogeneic cells was not due to cell-mediated cytotoxicity as measured by specific 51Cr release and staining with vital dyes. The transfer of antiviral activity from leukocytes to xenogeneic cells was blocked by rabbit antiserum to human leukocyte interferon. Transferred viral resistance failed to develop in actinomycin D-treated xenogeneic cells, even though these cells induced human leukocyte interferon. Based on these findings, it appears that interferon made in the cocultures acts on the leukocytes to effect the transfer of interferon-induced viral resistance to the xenogenic cells, possibly by transmission of an inducer for the antiviral state. These studies strongly suggest a new and efficient host defense against virus infection which does not require killing of noninfected or recently infected cells.

Animals↗
PubMed1980

Human fibroblast interferon in tears of patients with picornavirus epidemic conjunctivitis.

We report the levels of coxsackievirus type A24 (CA24) and the levels and type of interferon produced early during naturally acquired picornavirus epidemic conjunctivitis. Virus levels ranging from 10(1.8) to 10(5.8) 50% tissue culture infective doses per ml were detected in 29 of 37 acute (collected 1 to 4 days after onset of conjunctivitis) tear samples. Interferon (10(1.5) to 10(3.3) U/ml) was detected in 12 of 29 tear samples collected on day 1, in 2 of 6 tear samples collected on day 2, and in 1 tear sample collected on day 3 after onset of conjunctivitis. The interferon activity in pooled tear samples was completely neutralized by antiserum against human fibroblast interferon, stable at pH 2.0, and active against different viruses. In addition, the interferon activity in tears, like human fibroblast and leukocyte interferons produced in vitro, protected human and rabbit, but not mouse, cells. This is the first report of production and identification of the antigenic type of interferon induced by an enterovirus during natural infection. The early appearance of fibroblast interferon suggests that it may be an important host defense at the local site of implantation against this and possibly other enterovirus infections.

Animals↗
PubMed1980

Replication of acute hemorrhagic conjunctivitis viruses in conjunctival-corneal cell cultures of mice, rabbits, and monkeys.

Acute hemorrhagic conjunctivitis (AHC) viruses--enterovirus type 70 (E70), and coxsackie-virus type A24 (CA24)--infect the superficial cells of the conjunctiva and cornea. We examined the growth of several E70 and CA24 isolates in monkey, rabbit, and mouse conjunctival and corneal (C/C) cells. We found that E70 isolates grew well in monkey (10(6.5) TCID50/ml), rabbit (10(4.5) to 10(5.5) TCID50/ml), and mouse (10(3.5) to 10(6.0) TCID50/ml) C/C cultures and caused cytopathic effects (CPE). In contrast, CA24 isolates replicated well and caused CPE only in monkey C/C cultures (10(6.5) TCID50/ml). These results show that E70 isolates grow readily in monkey, rabbit, and mouse C/C cells whereas CA24 isolates replicated in monkey C/C cells only. This finding is consistent with the suggestion that a lower animal reservoir may be a source of human infection by E70. These cell culture systems may be useful for studying virus-cell interactions and host defenses operating at the surface of the eye and for evaluating the feasibility of prophylactic or therapeutic use of interferon, interferon inducers, and/or antibody for controlling AHC virus infections.

Acute Disease↗
PubMed1979

Early-appearing antiviral activity in human tears during a case of picornavirus epidemic conjunctivitis.

The clinical, virological, and immunological courses of a laboratory-acquired hemorrhagic conjunctivitis were followed. Coxsackievirus type A24 (CA24) was isolated from tears for only two days but from sputum and fecal samples for 20 days. Maximal levels of virus were detected in the right eye (10(5.1) 50% tissue culture infective doses/ml) 5-7 hr before conjunctivitis in the right eye, and in feces (10(2.8) 50% tissue culture infective doses/g) and sputum (10(2.5) 50% tissue culture infective doses/ml) five and eight days after onset of conjunctivitis, respectively. Specific neutralizing activity against CA24 was detected in tear samples 48-56 hr after exposure, and elimination of virus was associated with the rise in the neutralizing activity in tears. This activity was detected earlier than previously reported antibody responses of the eye. The absence of interferon and the association of this early neutralizing activity in tears with early elimination of virus from the eye suggest that neutralizing activity may play a major role in the clinical and pathological manifestations of this infection.

Antibodies, Viral↗
PubMed1979

Effect of specific antibodies on chronic echovirus type 5 encephalitis in a patient with hypogammaglobulinemia.

The effects of specific antibodies in chronic echovirus type 5 (echo 5) encephalitis were investigated in a patient with x-linked hypogammaglobulinemia. Virus was detected in cerebrospinal fluid (CSF) and blood despite treatment with commercial human gammaglobulin that contained low titers of antibodies to echo 5 (0.6 x 10(4) units per injection). Virus disappeared from blood and CSF when plasma containing high concentrations of antibodies (total dose, 1--4 x 10(4) units/kg) was administered intravenously. Maximal inhibition of virus was achieved in culture and in the patient's CSF when the titer of antibody to echo 5 in CSF was greater than or equal to 16 units/ml. Although the patient died, hyperimmune plasma improved the neurologic status and eliminated detectable virus from the blood and CSF.

Agammaglobulinemia↗
PubMed1979

Large-scale production and physicochemical characterization of human immune interferon.

Large-scale production of crude high-titered (10(2.3) to 10(4) U/ml) human immune interferon (type II) was carried out in roller bottle cultures of human peripheral lymphocytes by using the T-cell mitogen staphylococcal enterotoxin A. Over 99% of human immune interferon was destroyed by pH 2 or heat at 56 degrees C for 1 h. The interferon was not neutralized by antibody to human leukocyte interferon. The kinetics of development of the antiviral state were slow for immune interferon relative to those for leukocyte interferon. Ultrogel AcA 54 chromatography of crude or the concentrated interferon resulted in two peaks of activity, a major one (87% of recovered activity) with a molecular weight of 40,000 to 46,000 and a minor peak of molecular weight 65,000 to 70,000. The column elution buffer consisting of 18% ethylene glycol and 1 M NaCl in phosphate-buffered saline resulted in at least 100% recovery of added interferon. The data suggest, then, that the interferon produced under large-scale conditions was immune (type II). The efficiency of the production was comparable to that described for large-scale production of human leukocyte interferon. Our large-scale production system for human immune interferon offers a feasible approach to preparation of large quantities of purified immune interferon for structure studies, antibody production, and clinical application.

Cell Line↗
PubMed1978

Efficient transfer of interferon-induced virus resistance between human cells.

The rate of development of interferon-induced virus resistance in a mixture of two human cell types (U and WISH) is determined by the cell type (WISH) in the mixture which responds first. This phenomenon has been shown with two types of interferon assay procedure, and with both vesicular stomatitis virus and Sindbis virus. The transfer of virus resistance from one human cell (WISH) to another (U) (homospecific transfer) is much more efficient than the transfer from mouse L cells to WISH cells (heterospecific transfer), as shown by a much lower ratio of donor to recipient cells required for maximum transfer as well as a more rapid transfer. Thus, virus protection afforded by the interferon system is amplified more efficiently in mixtures of different human cells than in mixtures of mouse and human cells. These results suggest that, in a mixed population of cells such as occurs in vivo, more slowly responding cells might be influenced by cells which respond more rapidly to interferon. A defensive role is suggested for this mechanism which amplifies protection due to interferon.

Animals↗
PubMed1978

Biological effects of staphylococcal enterotoxin A on human peripheral lymphocytes.

The mitogenicity, ability to induce immune interferon, and relationship between interferon synthesis and cell proliferative response were studied using human peripheral lymphocytes stimulated by staphylococcal enterotoxin A (SEA), phytohemagglutinin-P (PHA-P), and concanavalin A (ConA). Maximum cell proliferative responses ([(3)H]thymidine incorporation) and protein synthesis ((14)C-amino acid incorporation) occurred on days 3 and 4, respectively, after stimulation by each of the three mitogens. Maximal immune interferon levels were found 3 or 4 days after mitogen stimulation. SEA-treated cultures produced approximately three times more interferon than did cultures stimulated with PHA-P or ConA. Furthermore, SEA stimulated maximal cell proliferation over a much broader concentration range than did PHA-P and ConA (SEA, 10(-5) to 10(2) mug/ml; PHA-P, 10(1) to 10(2) mug/ml; ConA, 10(1) to 10(1.5) mug/ml). Interferon was also produced at maximal or near maximal levels over a broad concentration range of SEA (10(-2) to 10(2) mug/ml). Also, we found that inhibition of mitogen-induced DNA and protein synthesis to control levels by mitomycin C or cytosine arabinoside partially reduced interferon production. The DNA inhibitor studies indicate that immune interferon synthesis occurs maximally in association with at least some proliferative response and that submaximal levels of interferon production occur in mitogen-treated cultures in the absence of detectable proliferation. The ability of SEA to stimulate maximal DNA and immune interferon synthesis at concentrations of 3.5 x 10(-13) M and 3.5 x 10(-10) M, respectively, puts it in a potency range similar to that of hormones. Thus, SEA may play an important role in gut immunity and Staphylococcus aureus infections at concentrations well below those required for emetic effects.

Bacterial Proteins↗