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Biomedical subjects

I Sarov

Publications and source records attributed to I Sarov.

At least 127 records · Page 7Linked to original sources
PubMed1982

Interaction between vaccinia virus and human blood platelets.

The objective of the present study was to characterize the interaction between human platelets and vaccinia virus and to examine possible impairment of platelet functions. The vaccinia virus was selected for our model system because it lacks detectable neuraminidase activity. Platelets were incubated with purified viral particles labeled with 3H-thymidine and binding parameters were analyzed. Binding reached saturation with an average of 5 particles/platelet. It was not affected by the plasma but was sensitive to temperature and to metabolic inhibitors. 3H-thymidine-labeled vaccinia virus and formaldehyde-fixed platelets were used to measure viral adsorption. The adsorption was temperature-independent but was affected by ionic strength, indicating electrostatic interactions. Treatment of the fixed platelets with neuraminidase or with alkaline phosphatase reduced viral adsorption, indicating that sialate and phosphate residues on the platelet surface may be involved in the adsorption. Platelet activities were markedly affected by vaccinia virus. The virus caused a dramatic 14C-serotonin release with no added inducer. The release was inhibited by aspirin, a known inhibitor of serotonin release related to prostaglandin synthesis. Furthermore, the virus inhibited platelet aggregation, induced by either ADP, collagen, or thrombin. This study demonstrates that although vaccinia virus lacks neuraminidase activity, it does bind to platelets and affects their function.

Adsorption↗
PubMed1982

Serum amyloid A (SAA) in viral infection: rubella, measles and subacute sclerosing panencephalitis (SSPE).

Serum amyloid A (SAA) levels were determined in the serial serum samples of eight rubella, 10 measles and seven subacute sclerosing panencephalitis (SSPE) patients. An early rise in SAA levels was detected in the acute phase in rubella and measles, followed by a prompt decrease in the convalescent phase. In a number of measles and rubella patients from whom early serum samples were available, the rise of SAA levels could be demonstrated before specific viral antibodies could be detected by complement fixation (CF) (measles) and haemagglutination inhibition (HI) (rubella). In only one rubella and one measles patient was no rise of SAA level detected. In SSPE only a moderate increase in SAA levels was noted except in one patient during a temporary deterioration, at which time the SAA level was very high; it returned to close to normal shortly thereafter. The possibility that SAA levels might be of value in monitoring the severity of infections, the recovery process and effects of anti-viral agents is discussed.

Adult↗
PubMed1981

A rapid immunoperoxidase assay for determination of IgG antibodies to measles virus.

A new indirect peroxidase antibody to membrane antigen (IPAMA) technique for the detection of IgG specific antibodies against measles virus is described. The technique utilizes as antigen measles-infected Vero cells dried on glass slides and stored at --70 degrees C. Sera of 509 healthy medical students and laboratory workers and 24 sera of measles, encephalitis, and subacute sclerosing panencephalitis (SSPE) patients were checked by IPAMA and the results have been compared with the results obtained by the hemagglutination-inhibition (HI) test. There is good agreement between the results of both techniques as to the presence or absence of antibody in 48 out of the 50 tested. The advantages of the techniques are discussed.

Animals↗
PubMed1981

Detection of specific IgA antibodies in serum of patients with varicella and zoster infections.

A sensitive solid-phase, enzyme-linked immunosorbent assay (ELISA) was developed for detection of serum IgA antibodies to varicella-zoster virus (VZV). The antigen consisted of a sonically disrupted extract of VZV-infected human embryo cells. Rabbit antihuman IgA peroxidase conjugate was used to detect human IgA bound to viral antigens. In parallel, IgM and IgG antibodies to VZV were studied by ELISA and by an immunoperoxidase antibody to membrane antigen technique, respectively. VZV IgA antibodies were detected in high titers in all 5 varicella and 8 zoster patients. Specific VZV IgM antibodies were detected in all 5 varicella patients, but only in 2 of 8 zoster patients. No VZV IgA antibodies (less than 40) were detected in 50 healthy control sera. Neither were they found in paired sera of 5 patients with herpes simplex infections, 2 patients with Epstein-Barr virus infections, and 5 patients with human cytomegalovirus infections. The potential application of ELISA IgA techniques in serodiagnosis of both primary and reactivated VZV infections is discussed.

Adult↗
PubMed1981

Detection of specific IgA antibodies in serum of kidney transplant patients with recurrent cytomegalovirus infection.

59 sera of 10 immunosuppressed renal allograft recipients who experienced recurrent cytomegalovirus (CMV) infection were analyzed by enzyme-linked immunosorbent assay (ELISA) for CMV IgA antibodies and by the complement-fixation (CF) test. A significant rise of CF titer was evident 4-53 weeks post-transplantation. 9 patients produced CMV IgA in high titers at about the time of CF antibody rise was observed. 1 patient did not produce IgA antibodies to CMV. In 3 of the 9 patients, specific CMV IgA antibodies were detected before the rise if CF titer was demonstrated. CMV IgA antibodies were found to persist for as long as 6 weeks post-transplantation. The potential application of ELISA detection of CMV-specific IgA antibodies as an early indication of CMV infection in kidney transplant patients is discussed.

Adult↗
PubMed1981

Antibody pattern to human cytomegalovirus in patients with adenocarcinoma of the colon.

The role of human cytomegalovirus (CMV) was examined according to serological patterns in 37 patients with adenocarcinoma of the colon (ACC). The sera were examined for the presence of IgG antibodies by the immunoperoxidase antibody to membrane antigens (IPAMA) method and by the complement-fixation (CF) test. Antibody determinations were also performed by the IPAMA method for three other members of the herpesvirus group: Epstein-Barr virus (EBV), herpes simplex virus (HSV) and varicella-zoster virus (VZV). Comparison groups included normal subjects, ACC patients treated with chemotherapy, and patients operated on for benign diseases. No significant difference was found in the geometric mean titers (GMTs) for CMV and the other herpesviruses in the sera of nontreated ACC patients when compared with the control groups. However, a significantly elevated antibody titer to CMV was found in chemotherapy-treated ACC patients by both the IPAMA and CF methods. In this group, elevated titers were found by the IPAMA method for EBV and HSV, but not for VZV. The significance of serological studies in elucidating the role of CMV in ACC patients is discussed.

Adenocarcinoma↗
PubMed1981

Detection of anti-platelet antibodies in patients with idiopathic thrombocytopenic purpura (ITP) and in patients with rubella and herpes group viral infections.

A highly sensitive enzyme-linked immunosorbent assay (ELISA) technique was observed for serological detection of antibodies against platelets. A covalently bound to Sepharose CL-4B was used to enrich sera in the IgG3 subclass of antibodies. The ELISA procedure as applied to detect anti-platelet antibodies in patients with herpes or rubella viral infections and in patients with idiopathic thrombocytopenic purpura (ITP). Twenty-eight sera from 13 thrombocytopenic patients showed high levels of anti-platelet antibodies. Two splenectomized patients in remission became negative for anti-platelet antibodies. Seventy-four sera from patients with serological diagnosis of herpes group viral infections comprising 10 cases of cytomegalovirus, nine cases of varicella or zoster, six cases of herpes simplex and four cases of Epstein-Barr virus were examined for the presence of anti-platelet antibodies. Except for two patients with varicella and zoster and one patient with rubella infection, all cases examined showed positive titres of anti-platelet antibodies. Sera from a group of 51 healthy controls were evaluated for anti-platelet antibodies. Forty-nine (96%) were negative (less than 40), whereas the other two were only slightly positive.

Adolescent↗
PubMed1980

Detection of human cytomegalovirus-specific IgG antibodies by a sensitive solid-phase radioimmunoassay and by a rapid-screening test.

A radioimmunoassay (RIA) for the detection of human IgG antibodies to cytomegalovirus (CMV) which utilizes extracts of CMV-infected cells as antigen is described. Sera of 66 healthy adults were titered by the RIA and by the complement fixation (CF) test. These same subjects were also used in the evaluation of a rapid screening radioimmunoassay (RSRIA) developed to detect IgG antibodies to CMV in small serum samples. The specificity of the RIA was evaluated by testing sera of seven CMV patients and ten patients with heterotypic titer rises to herpes simplex virus or varicella zoster virus (HSV or VZV). The RIA proved to be sensitive and specific. Possible applications of the RSRIA modification are discussed.

Antibodies, Viral↗
PubMed1980

Determination of IgA antibodies to human cytomegalovirus by enzyme-linked immunosorbent assay (ELISA).

A sensitive enzyme-linked immunosorbent assay (ELISA) is described for detection of IgA antibodies cytomegalovirus (CMV). The antigen consisted of a sonicated extract of CMV infected human embryo cells. The tested sera were absorbed with staphylococcus aureus (strain Cowan 1) before analysis. Rabbit antihuman IgA peroxidase conjugate was used to detect human IgA bound to viral antigen. In parallel, Igm and IgG antibodies to CMV were studied by ELISA and by the immunoperoxidase antibody to membrane antigen (IPAMA) technique, respectively. CMV IgA was detected in high titers by ELISA in eight of nine CMV patients. The maximal IgA titers were generally lower than the IgM titers detected by ELISA. No CMV IgA antibodies (titer less than 20) were detected by ELISA in 57 control sera (healthy adults, hospitalized patients with various other diseases), paired sera of five patients with acute herpes simplex, infection, two patients with Epstein-Barr infections, one patients with varicella, and one with zoster infections. The potential application of the ELISA CMV IgA technique in serodiagnosis of CMV infections is discussed.

Adolescent↗
PubMed1980

Enzyme linked immunosorbent assay (ELISA) for determination of IgG antibodies to human cytomegalovirus.

A solid-phase enzyme linked immunosorbent assay (ELISA) for determination of IgG antibodies to cytomegalovirus (CMV) is described. The assay used purified CMV and extracts of CMV infected cells as antigen. Antigens were desiccated onto the bottom surface of polystyrene microcuvettes. The antibodies bound to the antigens were assayed by anti-IgG-alkaline phosphate conjugate followed by addition of the enzyme substrate. Titration curves have been obtained from the sera of 35 blood donors and of 23 patients. Comparison of results obtained by ELISA with those obtained by complement fixation (CF) shows that there is agreement between the tests. Both purified CMV and extracts of CMV infected cells were found to be suitable antigens. Purified CMV was of value particularly in those sera which show high reactivity against control antigen. The ELISA technique described is approximately 412 to 548 times more sensitive than the CF test when purified CMV or extracts of CMV infected cells, respectively, are used as antigens. No significant heterotypic rise to CMV was observed by ELISA in three sets of sera with seroconversion to herpes simplex virus. The ELISA technique gives objective results, is easily performed, and may be adaptable as a routine test both for serological diagnosis of CMV infection and for screening of the general population.

Adult↗
PubMed1980

Enzyme-linked immunosorbent assay for detection of virus-specific IgM antibodies to varicella-zoster virus.

A sensitive enzyme-linked immunosorbent assay (ELISA) is described for detection of varicella-zoster virus (VZV) IgM antibodies. The antigen consisted of a sonically disrupted extract of VZV-infected human embryo cells. The tested sera were absorbed with Staphylococcus aureus (strain Cowan I) before analysis. Rabbit anti-human IgM peroxidase conjugate was used to detect human IgM bound to viral antigen. The results were compared with those obtained by the indirect fluorescent antibody to membrane antigen (IFAMA) technique. Comparison of titers obtained by ELISA with those obtained by IFAMA for sera of chickenpox patients showed agreement between the results in 8 of 9 patients. In 1 chickenpox patient, no VZV IgM antibodies could be detected by IFAMA, while a titer of 3,200 was obtained by ELISA. The ELISA technique described gave titers more than 100 times higher than those obtained by IFAMA. VZV IgM antibody was detected by ELISA and IFAMA in only 1 of 5 zoster patients. No VZV IgM antibodies were found by ELISA in 45 control sera (healthy adults and hospitalized patients with various other diseases). Neither were they found in paired sera of 6 patients with acute herpes simplex infections, 2 patients with Epstein-Barr virus infections, and 3 patients with human cytomegalovirus infections.

Antibodies, Viral↗
PubMed1980

Immunoperoxidase antibody to human cytomegalovirus-induced membrane antigen assay in the absence of interfering immunoglobulin G receptors.

An indirect peroxidase antibody to membrane antigen (IPAMA) technique was applied for determination of immunoglobulin G (IgG) antibody to human cytomegalovirus (CMV). The antigen consisted of air-dried, CMV-infected cells. The results were compared with those obtained with the CMV complement-fixation (CF) test. Comparison of titers obtained by IPAMA with those obtained by CF for sera of 48 healthy adults and 7 CMV patients showed good agreement between the tests. No cross-reactivity with other herpesviruses was observed. There was no problem of nonspecific cytoplasmic reaction with Fc receptors for IgG, even at low serum dilutions. The IPAMA technique appears to be reliable, is easily and rapidly performed, and is recommended as a routine test for serological diagnosis of CMV infections as well as for screening the general population.

Antibodies, Viral↗
PubMed1980

Enzyme-linked immunosorbent assay for detection of antibodies to varicella zoster virus.

A sensitive enzyme-linked immunosorbent assay (ELISA) is described for detection of varicella zoster virus (VZV) IgG antibodies. The antigen consisted of a sonicated extract of VZV-infected human embryo cells. Goat antihuman IgG peroxidase conjugate was used to detect human IgG bound to viral antigen. The results have been compared with those obtained by the indirect peroxidase antibody to membrane antigen technique (IPAMA). Comparison of titers obtained by ELISA with those obtained by IPAMA in sera of 41 medical students, six chickenpox patients and six herpes zoster patients showed good agreement between the tests as to the presence or absence of antibody. ELISA was about 88 times more sensitive than IPAMA. The specificity and sensitivity of ELISA as compared to other serologic techniques for detection of antibody to VZV is discussed.

Chickenpox↗
PubMed1980

Viral infection and acute peripheral facial palsy. A study with herpes simplex and varicella zoster viruses.

The role of herpes simplex virus (HSV) and varicella zoster virus (VZV) in acute peripheral facial palsy (APFP) was evaluated according to clinical symptomatology and serologic findings in a series of 70 patients seen over a one-year period. Peak morbidity of APFP occurred in the 21 to 30 years age group. Most patients were under 40 years of age and there were more female than male patients. Concomitant dysfunction of one or more other cranial nerves was present in most patients. The sera of patients were examined for IgG antibodies to HSV and VZV by the indirect immunoperoxidase technique. The geometric mean titer for VZV antibodies was significantly higher in the VZV-seropositive APFP patients than in the seropositive matched healthy control subjects. Nine APFP patients had increased or fourfold-rising VZV antibody titers on subsequent examinations, although six of them had presented without any evidence of zosterian eruption. The proportion of APFP patients with HSV antibodies at the time of admission was significantly higher than that of matched control subjects. No significant difference was found in the geometric mean titer for HSV antibodies between seropositive APFP patients and the seropositive control subjects. Only one patient in the series showed a fourfold rise in HSV antibodies, although the clinical symptomatology was compatible with this infection in 17 patients. The significance of serologic studies in determining the etiology of APFP is discussed.

Adolescent↗
PubMed1979

Antibody to varicella-zoster virus-induced membrane antigen: immunoperoxidase assay with air-dried target cells.

A technique using indirect immunoperoxidase antibody to membrane antigen (IPAMA) was developed for detection of IgG antibody to varicella-zoster virus (VZV). The IPAMA technique utilizes glass slides with air-dried VZV-infected cells, which can be stored at -70 C and used for several months without loss of sensitivity. Antibody titers measured by the IPAMA technique were comparable to those measured by the technique using indirect fluorescent antibody to membrane antigen (IFAMA) for sera obtained from 63 medical students as well as sera from three patients with chicken pox and nine with herpes-zoster infection, and the sensitivity of the IPAMA was equal to that of the IFAMA technique. No cross-reactivity with antibodies to other herpesviruses was observed.

Antibodies, Viral↗
PubMed1979

Sensitive solid-phase radioimmunoassay for detection of human immunoglobulin G antibodies to varicella-zoster virus.

A sensitive solid-phase radioimmunoassay for detection of antibodies to varicella-zoster virus (VZV) is described. The antigen consisted of a sonically disrupted extract of VZV-infected human embryo cells. 125I-labeled rabbit anti-human immunoglobulin G (IgG) specific for the Fc portion of human IgG was used to detect human IgG bound to viral antigen. With this technique, 193 human sera were evaluated for their IgG antibody titer against ZVZ. Subjects included 62 healthy adults, 33 young children (12 healthy), and 49 patients. Titers obtained by the radioimmunoassay were compared with those obtained by indirect fluoresence antibody staining of membrane antigen. The radioimmunoassay technique described gave titers approximately 5 X 10(4) times higher than those shown by indirect fluorescence. It can be used for routine diagnosis, but is especially suited to determining immune status to VZV, as defined by presence or absence of antibodies to the virus; for epidemiological studies; or for determining patients at risk who are exposed to the virus. No heterotypic titer rises to VZV were observed in sera with fourfold or greater rises to Epstein-Barr virus or cytomegalovirus. Sera of eight subjects with fourfold or greater titer rises to herpes simplex virus reacted in various ways: in six cases no significant change occurred in titer to VZV; one had a significant decrease in titer by the radioimmunoassay; and one had a significant increase. Possible reasons for these titer changes are discussed.

Adult↗