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Biomedical subjects

R C Kennedy

Publications and source records attributed to R C Kennedy.

At least 127 records · Page 7Linked to original sources
PubMed1987

Use of a resin-bound synthetic peptide for identifying a neutralizing antigenic determinant associated with the human immunodeficiency virus envelope.

A polyamide-based solid-phase support containing an acid-stable p-(oxymethyl)benzoic acid handle to anchor the COOH-terminal amino acid was utilized in the production of synthetic peptides analogous to amino acid sequences 503-532 from the human immunodeficiency virus (HIV) envelope glycoprotein. The resin-bound peptide was used to induce an antibody response to the native form of glycoprotein 120 in both rabbits and mice. This epitope was detected on the surface of HIV-infected cells and was capable of inducing an in vitro neutralizing HIV antibody response. In addition, sera from some individuals exposed to HIV react with this peptide bound to the resin in a solid-phase immunoassay. These data indicate that we have identified a neutralizing antigenic determinant present on the amino-terminal glycoprotein 120 subunits of HIV by utilizing resin-bound synthetic peptides.

Acquired Immunodeficiency Syndrome↗
PubMed1987

Number of mitral cells and the bulb volume in the aging human olfactory bulb: a quantitative morphological study.

The present study documents the morphological changes in the aging human olfactory bulb. Eight bulb pairs from white females between the ages of 25 and 102 years were used. The number of mitral cells in layers IV and III was determined for each bulb and corrected for split cell error. Counts were made on 10-micron thick Nissl-stained sections at 250-micron intervals. The mean number of mitral cells per olfactory bulb at age 25 was estimated from linear regression to be 50,935; at age 60, 32,718; and at age 95, 14,501. The average loss over the time interval studied was 520 mitral cells per year. The volume of each bulb layer, except layer IV, was determined. The difference in the volume of each layer within individuals with age and the total volume with age was not significant (P less than 0.11). The estimated mean bulb volume was found to be 50.02, 43.35, and 36.68 mm3 at ages 25, 60, and 95 years, respectively. The estimated reduction in bulb volume per year increase of age was 0.19 mm3. The ratio of mitral cells to bulb volume for layer III decreased by 19.4 units for every year increase in age. No significant difference was found between the left and the right bulbs in regard to the number of mitral cells and the bulb volume. Histologically, the glomerular layer thickness as well as the mitral cell size and concentration per unit area decreased with age. The intrabulbar anterior olfactory nucleus was discontinuous, highly variable in size, and presumably variable even in neuronal numbers.

Adult↗
PubMed1987

A common anti-DNA idiotype in sera of patients with active pulmonary tuberculosis.

The sera of 57 patients with active, untreated pulmonary tuberculosis were examined for the presence of a common anti-DNA idiotype, 16/6. Thirty-four of the 57 sera (60%) had an increased level of the idiotype, as measured by enzyme-linked immunosorbent assay using a specific rabbit anti-16/6 serum. Of 28 matched control sera, only 1 (4%) was found to be positive for the idiotype. The sera of patients with tuberculosis also showed increased activity against a variety of antigens with which lupus autoantibodies are known to crossreact (e.g., single-stranded DNA, double-stranded DNA, polynucleotides, and cardiolipin). A correlation was observed between serum IgG and IgM levels and the 16/6 idiotype levels.

Adult↗
PubMed1987

Increased presence of common systemic lupus erythematosus (SLE) anti-DNA idiotypes (16/6 Id, 32/15 Id) is induced by procainamide.

Sixty-seven patients on treatment with procainamide were examined for the presence of two common idiotypes of anti-DNA antibodies (16/6 Id and 32/15 Id). These idiotypes have been shown previously to have clinical relevance in patients with systemic lupus erythematosus (SLE). An enzyme-linked immunosorbent assay (ELISA) with rabbit anti-Id antibodies revealed increased concentrations of the 16/6 Id and 32/15 Id in 25 (37%) and 16 (24%) patients, respectively. Five of eight patients with drug-induced lupus had elevated titers of both idiotypes. A high correlation (R = 0.56, P less than 0.001 for 16/6 Id) was found between Id levels and anti-single-stranded DNA (ssDNA) antibody titers and between 16/6 Id titers and antihistone antibodies (IgG, R = 0.43; IgM, R = 0.25). It seems that procainamide, a component known to be associated with drug-induced lupus, may induce an increased production of common anti-DNA idiotypes in apparently normal subjects.

Antibodies, Viral↗
PubMed1987

Common lupus anti-DNA antibody idiotypes in chronic liver diseases.

Chronic liver diseases may be associated with the appearance of antinuclear antibodies. To further analyze the relationship between connective tissue and liver diseases the sera of 88 patients with chronic liver disorders were examined for the presence of common lupus anti-DNA idiotypes (16/6-id, 134-id, and 32/15-id), using an enzyme-linked immunosorbent assay. The 16/6-id was found in 58 (65.9%), the 134-id in 43 (48.9%), and the 32/15-id in 13 (14.8%) of the patients' sera. Distinct diagnostic groups displayed different lupus anti-DNA idiotype profiles. Patients with primary biliary cirrhosis (PBC) and chronic active hepatitis (CAH) had mainly the 16/6 idiotype, while in alcoholic (AC) and in cryptogenic cirrhosis (CC) the 16/6-id and 134-id were the main idiotypes recorded. There was considerable correlation among the different anti-DNA idiotypes but not between any of these idiotypes and an unrelated common anti-HBsAg idiotype. The occurrence of the various idiotypes was not found to be correlated with increased serum immunoglobulin levels. It can be concluded that the similarities between chronic liver diseases and connective tissue diseases are extended also to the presence of specific common anti-DNA antibody idiotypes.

Autoantibodies↗
PubMed1987

Monoclonal anti-idiotypic antibody mimics the CD4 receptor and binds human immunodeficiency virus.

A monoclonal anti-idiotypic (anti-Id) antibody, HF1.7, was generated against anti-Leu-3a, a mouse monoclonal antibody (mAb) specific for the CD4 molecule on human helper/inducer T lymphocytes. The anti-Id nature of HF1.7 was demonstrated by the following properties. (i) It reacted in a solid-phase immunoassay with anti-Leu-3a and not with a panel of irrelevant mouse mAbs. (ii) It partially inhibited the binding of anti-Leu-3a to CD4+ T cells. (iii) It detected a common idiotype present on various anti-CD4 mAbs. Because the CD4 molecule represents the receptor site for human immunodeficiency virus (HIV), the etiologic viral agent of acquired immunodeficiency syndrome, we examined the ability of the anti-mAb HF1.7 to mimic CD4 and bind HIV. This anti-Id mAb reacted with HIV antigens in commercial HIV ELISAs and recognized HIV-infected human T cells but not uninfected cells when analyzed by flow cytofluorometry. Attesting further to the HIV specificity, the anti-Id mAb reacted with a recombinant gp160 peptide and a molecule of Mr 110,000-120,000 in immunoblot analysis of HIV-infected cell lysates. The anti-Id mAb also partially neutralized HIV infection of human T cells in vitro. These results strongly suggest that this anti-Id mAb mimics the CD4 antigenic determinants involved in binding to HIV.

Animals↗
PubMed1987

Temporal distribution of transmissible mink encephalopathy virus in mink inoculated subcutaneously.

Information was sought on the temporal distribution of transmissible mink encephalopathy virus in royal pastel mink inoculated subcutaneously with 10(3.0) 50% intracerebral lethal doses of the Idaho strain. As determined by intracerebral assay in mink, extremely little replication of the virus occurred during the preclinical stage of infection. It seemed largely limited to lymph nodes draining the site of inoculation. Virus first appeared in the central nervous system (CNS) at 20 weeks, when all mink were still clinically normal. Early spongiform degeneration, limited to the posterior sigmoid gyrus of the frontal cortex, was first found at 28 weeks, or a few weeks before onset of clinical disease in most of the mink. Once virus reached the CNS, where greater concentrations occurred than elsewhere, it appeared in many extraneural sites (spleen, liver, kidney, intestine, mesenteric lymph node, and submandibular salivary gland). These seemingly anomalous findings, especially the limited extraneural replication of virus as a prelude to infection of the CNS, suggest that mink are not natural hosts of the virus. The results of this study support the generally held view that transmissible mink encephalopathy arises from chance or inadvertent infection of ranch mink with an exogenous virus, most likely feed-borne wild scrapie virus.

Animals↗
PubMed1987

Human immunodeficiency virus neutralizing antibodies recognize several conserved domains on the envelope glycoproteins.

Serum neutralizing antibodies against the human immunodeficiency virus were frequently detected in infected individuals, and low or absent serum neutralizing titers correlated with poor prognosis. Multiple diverse human immunodeficiency virus isolates were found to exhibit similar susceptibility to neutralization by a panel of human seropositive sera, suggesting that neutralizing antibodies are largely directed against conserved viral domains. Furthermore, utilizing antisera raised against a library of synthetic env peptides, four regions which are important in the neutralization process have been identified within both human immunodeficiency virus envelope glycoproteins (gp41 and gp120). Three of these are in conserved domains and should be considered for inclusion in a candidate vaccine.

AIDS-Related Complex↗
PubMed1987

Experimental infection of sheep and goats with transmissible mink encephalopathy virus.

In a study to learn more about the pathogenicity of transmissible mink encephalopathy virus for the natural hosts of scrapie, 20 Cheviot sheep and 19 dairy goats were inoculated intracerebrally with the Idaho strain of the virus. Five sheep and nine goats became affected with a progressive neurological disease. The incubation period in the sheep varied from 45 to 80 months (mean, 65 months) and in the goats from 31 to 40 months (mean, 35 months). Except for degeneration of the cerebral cortex (neocortex), the disease was indistinguishable clinically and neurohistologically from scrapie. During two more passages of the virus in goats, the incubation period was shortened to 12 to 15 months, the morbidity rate rose to 100% (6/6 dairy goats and 3/3 African pygmy goats), and the cortical lesion became constant and more pronounced. By the intracerebral inoculation of pastel mink, transmissible mink encephalopathy virus was detected in the brains of several affected sheep and goats but not in extraneural sites (lymphoid tissues and intestine), except for a trace amount in the proximal colon of one goat. Even after two passages in goats, the virus remained nonpathogenic for the laboratory mouse. Despite the essential likeness of the experimental disease and scrapie, the common identity of their causal viruses remains to be determined. Even so, the results of this study are still compatible with the view that transmissible mink encephalopathy virus almost certainly is scrapie virus whose biological properties became altered by chance passage in mink, a carnivore and an aberrant host.

Animals↗
PubMed1987

A common anti-DNA idiotype and other autoantibodies in sera of offspring of mothers with systemic lupus erythematosus.

Since the immune response in fetuses of mothers with systemic lupus erythematosus (SLE) is unknown, we investigated sera from six mothers and their paired offspring by enzyme-linked immunosorbent assay (ELISA) for the presence of a common anti-DNA idiotype (16/6 Id) and, as control, for the presence of an unrelated public idiotype of antibody to hepatitis B surface antigen (HBsAg). In addition, maternal as well as fetal sera were evaluated for the presence of antibodies to ssDNA, dsDNA, poly(I), poly (dT), RNA, cardiolipin, total histones and the presence of lupus anticoagulant. Clinically active SLE mothers showed in general increased IgG and, to a lesser extent, IgM autoantibody activity. Circulating lupus anticoagulant was detectable in clinically active mothers only. All offspring of clinically active SLE mothers showed increased IgG autoantibodies to a variety of antigens, while IgM antibodies were detected in only one fetus. In contrast, fetuses of clinically inactive mothers showed only minor IgG activity. Common anti-DNA-idiotype (16/6 Id) activity also correlated with disease activity in both maternal and fetal compartments. One clinically active mother was 16/6-negative; her offspring was, however, positive, indicating de novo production of the idiotype by the fetus. In contrast, a control anti-HBsAg idiotype was not detected in either maternal or fetal sera. It therefore appears that offspring of clinically active SLE mothers serologically reflect maternal disease activity. Furthermore, autoantibodies and common idiotype of autoantibodies can be found within the fetal compartment even in the absence of such antibodies in the maternal serum. Discrepancies between mothers and offspring in IgM-autoantibody levels and the presence of new idiotypes in fetuses are indicative of fetal de novo autoantibody production.

Adult↗
PubMed1987

The sera of patients with Klebsiella infections contain a common anti-DNA idiotype (16/6) Id and anti-polynucleotide activity.

In view of recent reports linking Klebsiella pneumoniae with autoimmunity, we have examined the sera of 52 patients with urinary tract infection or septicaemia from this Gram-negative pathogen, for the presence of antibodies to DNA, polynucleotides, cardiolipin and a common anti-DNA idiotype 16/6. Up to 27% of these patients had anti-polynucleotide antibodies detectable, and in 37% the 16/6 idiotype was found. Absorption of the sera of two patients, with no DNA binding, against the Klebsiella polysaccharide K-30 induced a significant fall in both their anti-K30 antibody and 16/6 idiotype levels. Among 52 patients with other Gram negative infections a maximum of 17% and 19% respectively, had anti-DNA antibodies and the 16/6 idiotype present in their serum. In 37 normal controls, the rate of antibody and idiotype detection was 5% or less. The presence of autoantibodies in the serum of patients with Klebsiella infections may be the result of non-specific stimulation due to bacterial polyclonal activation. However, there might also be a specific stimulus triggered by idiotypic cross-reaction between autoantibodies and anti-Klebsiella antibodies.

Adult↗
PubMed1986

Induction of nuclear transport with a synthetic peptide homologous to the SV40 T antigen transport signal.

A system was developed for the analysis of protein transport to the nucleus. Carrier proteins cross-linked to synthetic peptides were microinjected into the cytoplasm of mammalian cells, and protein transport was evaluated by immunofluorescence staining of fixed cells. A 13-mer synthetic peptide containing seven amino acids homologous to SV40 T antigen was capable of inducing nuclear transport, but no transport was observed when proteins were coupled with a synthetic peptide homologous to a nuclear-transport-defective T antigen. The largest protein-peptide conjugate efficiently transported was ferritin (Mr 465,000). The rate of transport was influenced by the number of peptides per molecule of carrier protein and, to some degree, by the size of the carrier protein. Transport of some conjugates was almost complete in 15 min at room temperature.

Amino Acid Sequence↗
PubMed1986

Anti-idiotypic antibody vaccine for type B viral hepatitis in chimpanzees.

Anti-idiotypic antibodies (anti-Id) that contain an internal image component that mimics the surface antigen of hepatitis B virus (HBsAg) were used to immunize chimpanzees. Four injections of the rabbit anti-Id preparation elicited an antibody response to HBsAg (anti-HBs). The antibody specificity appeared to be against the anti-Id, since the anti-Id immunogen was shown to bind the chimpanzee anti-HBs. Two chimpanzees immunized with the anti-Id, along with two control animals that were either untreated or received a nonimmune rabbit immunoglobulin G preparation, were challenged with infectious hepatitis B virus. Both control chimpanzees developed clinical and serological characteristics consistent with an active hepatitis B virus infection, whereas the two anti-Id treated chimpanzees were protected from infection. Since chimpanzees provide a relevant model of a human response to hepatitis B virus immunization and infection, these results indicate that anti-Id preparations such as that described here might be candidates for vaccines against human diseases.

Alanine Transaminase↗
PubMed1986

Antiserum to a synthetic peptide recognizes the HTLV-III envelope glycoprotein.

In a study performed to determine which regions of the human T-cell lymphotrophic virus type III (HTLV-III) may represent vaccine candidates to prevent the acquired immune deficiency syndrome (AIDS), a synthetic peptide corresponding to amino acid sequence 735 to 752 of the precursor envelope glycoprotein of HTLV-III was used to immunize rabbits. The resulting rabbit antiserum to the synthetic peptide specifically recognized the precursor envelope glycoprotein (gp160) of HTLV-III. Human sera positive for antibody to HTLV-III reacted with this peptide. These findings indicate that synthetic peptides can be used to induce an immune response directed against a native envelope glycoprotein epitope of HTLV-III. The data are discussed in terms of using synthetic peptides to identify antigenic determinants involved in the induction of protective immunity and possibly as vaccine candidates against the etiologic agent of AIDS.

Animals↗
PubMed1986

Lack of genetic restriction by a potential anti-idiotype vaccine for type B viral hepatitis.

Anti-idiotype (anti-Id) reagents that bear an internal image capable of mimicking hepatitis B surface antigen (HBsAg) were used to induce an antibody to HBsAg (anti-HBs) response in both rabbits and chimpanzees. The anti-idiotype induced antibody response produced in rabbits recognized HBsAg determinants associated with the induction of protective immunity against hepatitis B virus (HBV). Attesting further to the specificity was the binding of the rabbit anti-idiotype to the anti-idiotype induced anti-HBs containing sera. Our findings suggest that genetic restrictions associated with the induction of an interspecies immune response may not be a limitation of anti-idiotype based vaccines. In addition, anti-idiotype immunization also produced an anti-HBs in chimpanzees, a species susceptible to infection with human HBV. These data demonstrate that internal-image-bearing anti-idiotype reagents can induce an immune response across species barriers. Additionally, the reagents represent a viable alternative approach to vaccination against agents such as hepatitis B virus that cause human disease.

Animals↗
PubMed1986

Human immunodeficiency virus gp120 glycoprotein detected by a monoclonal antibody to a synthetic peptide.

A chemically synthesized peptide corresponding to the amino acid sequence 503-532 of gp160 of human immunodeficiency virus (HIV) was used to generate monoclonal antibodies reactive with the env glycoprotein gp120. One monoclonal antibody, 120-1, was isolated that reacted with the peptide and with HIV antigen(s). Western blot analysis showed reactivity with two bands of 120 kDa and 88 kDa. 120-1 reacted in indirect immunofluorescence with 15-20% of infected human T cell line A3.01 as early as 4 days post in vitro infection, 2-3 days prior to detectable reverse transcriptase activity in supernatant fluids.

Amino Acid Sequence↗