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Biomedical subjects

A Salmi

Publications and source records attributed to A Salmi.

At least 127 records · Page 7Linked to original sources

An interferon assay based on yield reduction of vesicular stomatitis virus antigen measured by enzyme immunoassay.

A modification of yield reduction assay for interferon was developed. The standard micromethod of inhibition of cytopathogenic effect (CPE) of vesicular stomatitis virus (VSV) was first applied and the amount of virus antigen released to the supernatant was then measured by a competitive enzyme immunoassay technique. This assay was four times more sensitive than the CPE inhibition method and was able to detect 0.50-0.25 international units/ml of human interferon-alpha and was also applicable to interferon-gamma determinations. It is a suitable method when small volumes of samples containing low levels of interferon are tested.

Animals↗

Intrathecal immune responses in mumps meningitis patients.

The in vitro 3H-thymidine incorporation of peripheral blood (PB) and cerebrospinal fluid (CSF) lymphocytes from 11 mumps meningitis patients was studied after stimulation with non-specific mitogens and microbial antigens. Although corresponding viral antibodies were always found in the CSF of seropositive patients by a sensitive radioimmunoassay, their intrathecal synthesis was directed mainly against mumps virus. Most of the patients had PB lymphocytes that reacted on stimulation with phytohaemagglutinin (PHA) or pokeweed mitogen (PWM), but a smaller number of them had reactive CSF cells. Only four patients showed stronger responses to PHA in the CSF than in PB. Most patients had mumps-reactive lymphocytes in PB but only two of them in the CSF. In contrast, these patients more often had increased CSF cell reactivity when tested with purified protein derivative, measles, and herpes simplex virus antigens. The results could not be explained by a damaged blood-brain barrier alone but may reflect the immunological status of the brain compartment in these patients.

Adolescent↗

Immune complexes in serum and cerebrospinal fluid of multiple sclerosis patients and patients with other neurological diseases.

Paired serum and cerebrospinal fluid (CSF) specimens from 30 multiple sclerosis (MS) patients and 30 patients with other neurological diseases (ONDs) were analyzed for the presence of immune complexes (ICs). With each of the 4 tests used, ICs were found more frequently in sera from both MS and OND patients than in sera from healthy blood donors. IC-positivity for MS and OND patient CSF varied from 10-33% and from 10-17% in different tests. The number of IC-positive sera or CSF in MS patients did not differ significantly from those in OND patients. For both MS and OND patients, the positivity pattern for serum and CSF specimens in each IC test was essentially unique. Furthermore, because several CSF IC-positive and serum IC-negative paired specimens were found, intrathecal IC formation may be independent of IC formation in peripheral blood. The presence of ICs in serum or CSF did not correlate with the clinical status of or laboratory data on the MS patients, nor was a correlation found with the diagnosis of the OND patients. In total, these results suggest that the presence or absence of ICs in MS or OND patients may simply reflect changes in the immunological regulation of individual patients.

Adult↗

Intrathecal synthesis of virus antibodies in multiple sclerosis patients.

A follow-up study on the intrathecal synthesis of viral antibodies in multiple sclerosis patients was made on 28 patients over a period of about 2 years. Serial serum and cerebrospinal fluid specimens were assayed for antibodies against measles, rubella, parainfluenza type 2, respiratory syncytial, mumps, influenza A, influenza B, adeno, and herpes simplex viruses by employing a solid-phase enzyme immunoassay technique. All patients had local antibody synthesis against one or more of the antigens studied. Rubella and measles virus antibodies were found with the highest frequency and were synthesized at the highest rate. Simultaneous intrathecal antibody synthesis against the greater number of the viruses studied was associated with higher local immunoglobulin G synthesis. A good overall correspondence in the fluctuations of the different viral antibodies synthesized intrathecally was usually found. Sometimes the changes in intrathecal antibody levels correlated well with the changes in immunoglobulin G index and sometimes not. These fluctuations could not be correlated with the clinical course of the disease. The results of this study suggest that the viral antibodies studied are not relevant to the etiology or the pathogenesis of multiple sclerosis.

Adenoviridae↗

Antibodies to coronaviruses OC43 and 229E in multiple sclerosis patients.

Multiple sclerosis (MS) and matched control sera had similar antibody titers to coronaviruses OC43 and 229E when tested by a radioimmunoassay method. In contrast, cerebrospinal fluid from MS patients contained coronavirus antibodies more frequently and in higher titers than matched controls. Intrathecal antibody synthesis to OC43 and 229E viruses was detected in 41% (9/22) and 26% (7/27) of MS patients, respectively, but was not found in any of the neurologic control patients. This intrathecal antibody synthesis may mean that coronaviruses play an etiologic or pathogenic role in MS. Alternatively, intrathecal synthesis of coronavirus antibodies may be but part of a generalized and variable intrathecal antibody synthesis that is typical for MS patients.

Antibodies, Viral↗

Galactose oxidase labeling of membrane proteins from human brain white matter.

The use of galactose oxidase (EC 1.1.3.9) and tritiated sodium borohydride for labeling of membrane glycoproteins, described by Gahmberg and Hakomori, has previously been applied to the study of myelin glycoproteins of experimental animals. Rat brain myelin glycoproteins have been studied by sequential lectin affinity of chromatography and recently the lectin-binding capacity of rat central nervous system myelin glycoproteins has been characterized. Complex heterogeneity of the glycoprotein pattern of rat central nervous system myelin has been reported, and so a variety of glycoproteins can be expected to exist in human white matter membranes. Application of the galactose oxidase procedure to the study of human brain membranes could be useful in research concerning certain neurological diseases if the properties of autopsy brain material are taken into account. In this study, membrane proteins of human autopsy brain white matter were subjected to the galactose oxidase/NaB3H4 labeling procedure and the membrane labeled by this method or by the [3H]acetic anhydride techniques were studied by lectin affinity chromatography using Lens culinaris phytohemagglutinin (lentil lectin) attached to Sepharose 4B beads.

Cerebral Cortex↗

Prognosis of optic neuritis with special reference to cerebrospinal fluid immunoglobulins and measles virus antibodies.

Forty-eight patients with optic neuritis (ON), first seen in 1970 to 1973, were neurologically and neuroophthalmologically reexamined after 7 to 10 years. Twenty-seven patients (56%) had probable MS, and 9 (19%) had possible MS. During the attack of ON, the cerebrospinal fluid (CSF) samples and serum/CSF measles antibody ratios were studied. Twenty patients had increased relative immunoglobulin G (IgG) (% of total protein) in their CSF; 19 of these had probable or possible MS. However, 17 of 28 patients with a normal relative IgG value had also developed MS. CSF electrophoresis was abnormal in 20 patients with ON; reexamination showed that 19 had probable or possible MS. Sixteen of 27 patients with normal electrophoresis had also developed MS. Serum/CSF measles antibody ratio had decreased in 19 patients; 13 of these had probable MS and 3 had possible MS. Of 29 patients with a normal measles antibody ratio, 14 had probable MS and 6 had possible MS. The conclusion is that examination of the CSF in ON gives valuable prognostic information because increased relative IgG, abnormal electrophoresis, or a decreased measles antibody ratio implies a high risk of developing MS. A normal CSF does not, however, rule out the possibility of dissemination.

Antibodies, Viral↗

IgM-class rheumatoid factor in serum and cerebrospinal fluid of multiple sclerosis and matched neurological control patients.

Paired serum and cerebrospinal fluid (CSF) specimens from 30 multiple sclerosis (MS) patients and 30 matched neurological control (NC) patients were quantitatively tested for IgM-class rheumatoid factor (RF). Significantly elevated RF levels were found in serum from 6 MS patients and 12 NC patients. Seven of the latter 12 patients had a diagnosis of recurrent head pain. RF was detected in CSF from 2 MS patients and 2 NC patients. In 3 of the 4 cases, this could be explained by blood-brain barrier damage or normal diffusion of RF into CSF. Intrathecal RF synthesis was found in the remaining MS patient. These results suggest that RF production may be related to underlying pathological mechanisms in at least some MS and NC patients. They also confirm that RF must be carefully accounted for in etiological studies designed to demonstrate pathogen-specific IgM antibodies in, for example, MS patients.

Blood-Brain Barrier↗

Lymphocyte blast transformation responses and viral antibodies in relation to HLA antigens in multiple sclerosis.

Fifty four clinically stable multiple sclerosis (MS) patients and 54 age- and sex-matched control subjects were HLA-typed, and their responses to herpes simplex, measles, mumps and rubella antigens were examined by the lymphocyte blast transformation test and by serum antibody titrations. Blast transformation response to purified tuberculin (PPD), mitogen phytohaemagglutinin (PHA), pokeweed mitogen (PWN) and concanavalin A (Con A) and spontaneous proliferation of lymphocytes were also studied. MS patients differed from controls by higher antibody levels to measles and rubella viruses and by lower specific blast transformation responses to rubella and measles antigens. When the relative strength of transformation responses was measured, mumps and herpes simplex responses were also lower in MS patients than in controls. In addition, spontaneous lymphocyte proliferation of MS patients in 6-day cultures was lower than that of control lymphocytes. In mitogen stimulations there were no differences between whole groups, but the oldest patients had lower responses to PHA and Con A than their matched controls. The frequency of HLA-Dw2 was 56.6% in MS patients and 32.1% in controls. The patients with and without Dw2 differed from each other only by a lower specific response to PPD in the Dw2-positive group. The immunological response of Dw2-positive controls resembled that of MS patients: low transformation response to viral antigens, low spontaneous proliferation and elevated measles antibodies. This finding supports the function of a genetically determined type of immune responsiveness with low cell-mediated immunity and high levels of certain viral antibodies as one susceptibility factor in multiple sclerosis.

Adult↗

Intrathecal synthesis of antibodies to diphtheria and tetanus toxoids in multiple sclerosis patients.

Antibodies to diphtheria and tetanus toxoids were measured in 30 multiple sclerosis (MS) patients and 30 neurological control patients by enzyme-immunoassays. The frequency of antibody-positive patients and the titer distribution were similar in both groups. In spite of this, some MS patients had intrathecal antibody synthesis to these toxoids. The histories of these patents did not reveal any diseases caused by diphtheria of tetanus bacteria but they had been vaccinated 2-24 years before the first clinical symptoms of MS. The findings suggest that lymphocytes earlier committed to specific antibody synthesis outside the brain compartment could enter the brain before or after the clinical onset of MS.

Antibodies, Bacterial↗

Circulating immune complexes, immunoconglutinins, and rheumatoid factors in nephropathia epidemica.

Circulating immune complexes (CICs), immunoconglutinins, and antiglobulins were studied in nephropathia epidemica, an acute infectious hemorrhagic fever occurring in Finland and Scandinavia. Sixty-one serum specimens from 18 serologically confirmed patients were collected between day -5 and day 230 from the onset of fever. Five CIC tests, three immunoconglutinin tests, and various other tests were used to characterize the disease immunologically. CICs were found in all patients. The percentage detection of positive cases varied in the tests from 100% to 22%. A marked stimulation of levels of the IgM class of immunoglobulins were observed. Antiglobulin tests were positive for all of the patients. No correlation between the test results and the clinical severity of the disease could be found. Of special interest was the delay in the rise of CIC levels compared with the chromologic pattern of the clinical course. In some patients a prolonged appearance of CICs for eight months was observed.

Antibodies, Anti-Idiotypic↗

Detection of antigen-specific cellular immune response by the in vitro production of T-cell growth factor.

The amount of T-cell growth factor (TCGF) produced in vitro in antigen-stimulated lymphocyte cultures was measured by induction of growth in cell lines dependent on the factor. The method distinguished eight herpes-simplex-seronegative subjects from ten seropositive ones, and these results correlated with those of the lymphocyte blast transformation (LBT) test. The LBT responses and TCGF amounts produced in cultures with purified tuberculin (PPD) were also in good correlation (r = 0.833, P less than 0.001). Considerable levels of the factor were already present 12 h after the beginning of the culture. The method offers rapid quantification of cell-mediated immunity to specific antigens.

Antigens, Bacterial↗

Measurement of glial fibrillary acidic protein (GFAP) and anti-GFAP antibodies by solid-phase radioimmunoassays.

A solid-phase radioimmunoassay was developed for the detection of glial fibrillary acidic protein (GFAP) and GFAP-specific immunoglobulin G (IgG) antibodies. In antibody assays purified GFAP was absorbed onto polystyrene beads, followed by incubation in dilutions of serum. (125-I)-labelled human anti-IgG was used to quantify antibodies bound to solid-phase GFAP. GFAP in samples was measured by the inhibition of the binding of anti-GFAP antibody to solid-phase GFAP. The serum and CSF samples of 19 brain tumor, 40 multiple sclerosis and 66 control patients were assayed for anti-GFAP antibodies. The binding values in the serum and CSF samples of the brain tumor patient group were higher and the binding values in the CSF samples of the multiple sclerosis group lower than those of the control group. The differences were statistically significant.

Antibodies↗

Myelin basic protein antibodies in the serum and CSF of multiple sclerosis and subacute sclerosing panencephalitis patients.

A solid-phase radioimmunoassay was developed for the detection of myelin basic protein antibodies of immunoglobulin G (IgG) class. Purified basic protein of myelin (MBP) was adsorbed onto polystyrene beads, followed by incubation in dilutions of serum or cerebrospinal fluid (CSF). 125I-labelled anti-human IgG was used to quantify antibodies bound to the solid-phase. The assay was optimized in tests with rabbit antibodies to MBP and with 125I-labelled anti-rabbit IgG. Serum and CSF specimens from 41 multiple sclerosis (MS), 16 subacute sclerosing panencephalitis (SSPE) and 58 control patients were tested for MBP antibodies. No statistically significant differences were found between MS and control patient groups, but the subgroup of acute MS patients had slightly elevated (P 0.02) antibody levels in their CSF specimens. The SSPE patients had markedly elevated levels (P 0.001) of antibodies to MBP in their CSF specimens.

Adsorption↗

Lymphocyte blast transformation and antibody responses after vaccination with inactivated mumps virus vaccine.

Mumps antibody response and the development of cell-mediated immunity (CMI) to mumps antigen as assayed by the lymphocyte blast transformation method were studied after immunization with an inactivated mumps vaccine in seven sero-negative and ten sero-positive subjects. The transformation response of peripheral blood lymphocytes to mumps antigen generally appeared by 20 weeks post vaccination and reached levels found in sero-positive subjects years after mumps infection. There was no clear-cut correlation between the magnitude of blast transformation and antibody responses.

Antibodies, Viral↗

Evaluation of six tests for circulating IgG complexes with special reference to IgM rheumatoid factors: analysis of systemic lupus erythematosus and rheumatoid arthritis series.

Six tests for circulating immune complexes (CIC) developed in four laboratories and representing four main principles [affinity of human platelets, Clq, of RF for aggregated IgG, and of conglutinin (Kg) for complex-bound C3] were evaluated on series of SLE and definite RA. All tests detected human model complexes in the presence of NHS and discriminated the patient series from the blood donor series, most powerful being the PIPA (platelet test). The high correlation between the RF-binding inhibition tests (RFbI) and the RF-latex test suggested interference due to intrinsic RFs. This received further support from experimental analyses in which RA sera mixed with varying doses of heat-aggregated IgG were assayed by the pRFbI test.

Antigen-Antibody Complex↗

The glycoprotein of measles virus. External radioactive labelling of its carbohydrate and partial characterization of the glycopeptide.

Measles virus was propagated in VERO cells and purified from the culture supernatants by two successive tartrate-density-gradient centrifugations. Surface carbohydrates were labelled both in vitro and in vivo with 3H after treatment with galactose oxidase/NaB3H4 or with [3H]glucosamine. The major labelled glycoprotein in measles virions had a mol.wt. of 79 000. After labelling with periodate/NaB3H4, which would result in specific labelling of sialic acid residues, the 79 000-mol.wt. glycoprotein was very weakly labelled. This suggests that there is no or a very low amount of sialic acid in the virions. Further analysis of the glycoprotein showed that galactose is the terminal carbohydrate unit in the oligosaccharide, and the molecular weight of the glycopeptide obtained after Pronase digestion is about 3000. The oligosaccharide is attached to the polypeptide through an alkali-stable bond, indicating a N-glycosidic asparagine linkage.

Chromatography, Paper↗