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1.
Catalytically active antibodies, abzymes, appear in the blood of mammals immunized with the analogs of transition state or in the case of autoimmune diseases. Until recently, it was not shown whether abzymes exist in the blood of apparently healthy subjects. We have discovered that secretory IgA (sIgA) from the milk of healthy mothers catalyze phosphorylation of a variety of proteins and that IgG can hydrolyze DNA and RNA. In this study for the first time it is shown that IgG from human milk (and their Fab-fragments) also catalyze hydrolysis of nucleoside mono-, di-, and triphosphates. The data meet certain stringent criteria, unambiguously indicating that the observed catalytic activity is associated with IgG rather than contaminating enzymes. Although the nucleotide-binding site of IgG is located in the light antibody chain, L-chains per se cannot hydrolyze NTP unlike the DNA-hydrolyzing abzymes. Kinetic and thermodynamic parameters that characterize the interaction of NTP and dNTP with IgG-abzymes were analyzed. Possible reasons for appearance of polyclonal abzymes with different catalytic activities in the milk of healthy mothers are considered.  相似文献   

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Antibodies (Abs) hydrolyzing proteins, DNA, and RNA are detected in the blood of patients with various autoimmune diseases. In the present work, homogeneous preparations of IgG Abs from the blood of the healthy donors as well as patients with A, B, C, and delta types of viral hepatitis, influenza, pneumonia, tuberculosis, tonsillitis, duodenal ulcer, and some types of cancer were purified. For the first time, the fraction of IgG and its Fab fragments of patients with viral hepatitis were shown to have high DNA- and RNA-hydrolyzing activity. In case of Abs from the healthy donors and patients with other diseases, high activity of Abs was not detected. The data obtained by various methods indicate that the activity of hepatitis Abs is an intrinsic property of the immunoglobulins. The relative rates of hydrolysis of cCMP, poly(U), poly(A), poly(C), and tRNA(Phe) by hepatitis Abs were compared with those of RNase A and other RNases from human blood. Significant differences in activities of Abs and nucleases in hydrolysis of model substrates were demonstrated. Thus, catalytically active Abs can appear in the blood of patients not only with autoimmune disorders, but with viral diseases as well.  相似文献   

4.
We examined cerebral spinal fluid (CSF) from multiple sclerosis (MS) patients and patients with other neurological diseases (OND) for antibody specific for Human Herpesvirus-6 (HHV-6) and for HHV-6 DNA detectable by PCR. CSF from MS patients had a higher frequency of IgG antibody to HHV-6 late antigens (39.4%) compared with CSF from OND (7.4%). In contrast, the frequency of detectable IgG antibody in CSF from MS patients specific for Epstein-Barr Virus (EBV) (12.1%) and Human Cytomegalovirus (HCMV) (6.1%) was much lower. Two of 12 MS CSFs (16.7%) also contained HHV-6 DNA detected by PCR. None of four OND CSF were positive for HHV-6 DNA. Plasma from 16 patients with MS, eight with OND and 72 healthy donors were tested for antibodies by ELISA to HHV-6 early (p41/38) and late (gp110) proteins. Although no differences in anti-gp110 IgG antibody were detected between MS patients, patients with other neurological diseases, and normals, IgG antibody to early protein p41/38 was detected in > 68% of the plasma from MS patients, 12.5% from OND patients and 27.8% of the controls. IgM antibody to p41/38 was present in > 56% of MS patients, 12.5% of OND patients, and 19% of controls. These data suggest that more than half of the MS patients had active, ongoing HHV-6 infections. HHV-6 was also isolated from peripheral blood mononuclear cells (PBMC) from 3/5 MS patients who were in relapse or had progressive disease and was identified as HHV-6 Variant B. These preliminary results support the hypothesis that HHV-6 may be a co-factor in the pathogenesis of some cases of MS.  相似文献   

5.
Measles virus-specific antibodies were isolated from sera, cerebrospinal fluids (CSF), and brain extracts of patients with subacute sclerosing panencephalitis (SSPE) and multiple sclerosis (MS) by absorption with measles antigens and subsequent acid elution of the antigen-antibody precipitates. Electrophoretically homogeneous measles antibodies were isolated from CSF or brain extracts in five patients with SSPE and in five out of seven patients with MS. Homogeneous IgG antibodies were also demonstrated in the sera from all SSPE patients and from three of the MS patients. The antibodies isolated from various control sera and from pooled CSF were electrophoretically heterogeneous. The results support the concept of a local synthesis in the nervous system of oligoclonal IgG antibodies to measles virus in all patients with SSPE and in some patients with MS. In SSPE, most or all oligoclonal IgG proteins of the CSF or brain carry measles antibody activities. In MS, only part of the oligoclonal IgG appears to be associated with measles antibody activity.  相似文献   

6.
Antibodies to an axolemma-enriched fraction (AEF) antigen have been detected in the cerebrospinal fluid (CSF) and serum of patients with Multiple Sclerosis (MS) using an enzyme-linked immunosorbent assay (ELISA). A marginal elevation (P < 0.08) of anti-AEF IgG was found in MS CSF when compared with OND samples. When CSF was diluted to a standardized IgG concentration, the anti-AEF IgG level in MS CSF was significantly elevated (P=0.007) when compared to OND CSF. MS serum was also found to contain a significantly higher level (P < 0.001) of anti-AEF IgG when compared to OND serum using the ELISA technique.  相似文献   

7.
ATP : RNA adenyltransferase, purified from Escherichia coli, was used to add a series of adenosine residues to the 3'-end of MS2RNA. Incubations of the order of a few minutes at 37 degrees C were sufficient for synthesis of a short poly(A) chain that did not appreciably alter the hydrodynamic or electrophoretic properties of MS2 RNA. The size of the poly(A) tails was estimated by gel electrophoresis after prior hydrolysis of the primer RNA with pancreatic ribonuclease. These results were in good agreement with the values calculated on the basis of the relative amount of incorporated AMP. After the addition of a short poly(A) tail, approximately 50% of the treated material binds specifically to an oligo(dT)-cellulose column. The majority of the recovered poly(a)-containing RNA was still intact, as shown by analysis on polyacrylamide gel. After incubations beyond 6 min, slowly sedimenting material, also showing reduced electrophoretic mobility, was formed. Presumably this material corresponds to RNA chains to which long poly(A) tails are linked.  相似文献   

8.
Four neonates with convulsions had IgG antibodies in their cerebrospinal fluid (CSF) to varicella zoster virus (VZV). These antibodies were found in the sera of two of these patients after the age of 6 months. Antibodies to 16 different microbes were studied from the serum and CSF of 201 neonates with neurological problems. The presence of DNA specific to HSV-1, HSV-2, and VZV in the CSF was also investigated using the polymerase chain reaction (PCR). Antibodies to VZV were detected in the CSF of four neonates. Antibody indices suggested production of VZV specific antibodies in the central nervous system. These findings suggest that intrathecal production of antibodies to VZV can appear in neonates with neurological problems, which suggests that intrauterine VZV infection can be acquired without cutaneous symptoms in the mother.  相似文献   

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Anticardiolipin antibodies were studied in serum and cerebrospinal fluid from 32 consecutive patients with systemic lupus erythematosus, admitted for the assessment of neuropsychiatric disease. Ten of the 16 patients with active neuropsychiatric complaints showed positive anticardiolipin antibodies in cerebrospinal fluid, including eight with the simultaneous presence of antibodies in their sera. By contrast, only 2 of the 16 patients with headaches, lacking further data of neurological disease, revealed anticardiolipin antibodies in their cerebrospinal fluid. The assessment of Q-albumin index showed abnormal values in a subset of patients with active neuropsychiatric changes who showed positive cerebrospinal anticardiolipin antibodies, suggesting that an impairment of the blood brain barrier function may lead to a leakage of intrathecal antiphospholipid antibodies from systemic circulation. Additionally, few patients revealed normal Q-albumin values with high IgG-cerebrospinal fluid index suggesting increased intrathecal synthesis of autoantibodies. The study of anticardiolipin antibodies in cerebrospinal fluid was useful to detect active neuropsychiatric disease in systemic lupus erythematosus.  相似文献   

11.
Human cytomegalovirus (HCMV) encephalitis in adult nonimmunosuppressed patients has rarely been reported. We have diagnosed HCMV encephalitis in an anti-HCMV immunoglobulin G-negative, nonimmunosuppressed young woman by HCMV DNA PCR and virus isolation from cerebrospinal fluid (CSF). At the same time, HCMV antigen and HCMV DNA could be demonstrated in peripheral blood leukocytes, and the virus was isolated in fibroblast cultures. After 22 days of acute illness, the virus disappeared from the CSF. Remarkably, the patient did not generate detectable anti-HCMV antibodies within 5 months after the beginning of illness. To investigate the significance of HCMV DNA detection in CSF, samples of CSF, blood cells, and serum from 35 nonimmunosuppressed patients with various neurological disorders (but no herpes simplex virus central nervous system [CNS] disease) were tested for HCMV DNA, antigen, and antibodies. Eleven of these patients were found to be positive for virus DNA and/or antigen in peripheral blood leukocytes. Additionally, HCMV DNA was detected in the CSF of two patients with noninflammatory CNS diseases. A causative role of HCMV in the CNS diseases of these two patients was not evident. In summary, HCMV DNA amplification from CSF samples is a very suitable method to verify HCMV-associated encephalitis, but it should be taken into consideration that there are few cases of positive PCR with DNA from CSF without any known clinical correlative.  相似文献   

12.
BACKGROUND: HIV antibodies and HIV DNA have been detected in needles and syringes that have been used for intravenous injections in HIV-infected persons. During intravenous injection, blood is typically aspirated into the lumen of the syringe. During intramuscular or subcutaneous injection, however, blood is not usually introduced into the syringe. OBJECTIVES: To investigate the presence of HIV antibodies, HIV proviral DNA, HIV RNA, and human DNA in needles and syringes that had been used for intramuscular or subcutaneous injection in persons known to have HIV infection. METHODS: Discarded disposable needles and syringes used by health-care personnel for medically indicated intramuscular or subcutaneous injections of HIV-infected patients were collected. Residual material was extracted from the syringes. The extracts were analyzed by enzyme immunoassay for the presence of HIV antibodies. PCR was conducted to detect HIV and human DNA, as well as HIV RNA. RESULTS: HIV antibodies were detected in 16 (6.2%) out of 260 syringes. Human DNA or HIV-specific DNA were not detected. A second set of 80 syringes was collected to examine the presence of HIV RNA. HIV RNA was detected in three (3.8%) out of 80 syringes. CONCLUSION: This analysis demonstrates that the risk of transmitting HIV from syringes that have been used for intramuscular or subcutaneous injection may be low, but is not zero.  相似文献   

13.
Progressive multifocal leukoencephalopathy (PML), a viral-induced demyelinating disease, is becoming relatively common, while many diagnostic and pathogenetic aspects remain to be clarified. A study was therefore undertaken in 64 AIDS patients suffering from various neurological disorders, including PML (12 subjects), with the specific objective of searching for JC virus (JCV) DNA by nested PCR (n-PCR) in cerebrospinal fluid (CSF), peripheral blood mononuclear cells (PBMCs), and urine collected from all patients. CSF examination, CD4 and CD8 counts, neurological examinations, and neuroradiological investigations were undertaken. JCV DNA was detected in 92% of CSF specimens in 75% of the PBMCs and urine samples from the PML patients, whereas among the non-PML patients JCV DNA was not detected in any CSF samples, but was found in 10% of PBMCs and in 39% of the urine specimens. BKV and JCV DNA viruria was observed simultaneously in 6% of the AIDS patients without PML. The routine CSF tests including IgG oligoclonal bands, the Link, and Tourtellotte IgG indexes, did not show a typical pattern in PML cases. The data obtained clearly indicate that the detection of JCV DNA in CSF constitutes an efficient marker for PML diagnosis. The simultaneous presence of JCV DNA in the CSF, PBMCs, and urine samples from the PML patients, who did not differ from controls with regard to their immunosuppressive status, suggests that JCV could be carried into the central nervous system (CNS) by infected PBMCs.  相似文献   

14.
The costimulatory CD80 and CD86 molecules were measured by flow cytometry on cerebrospinal fluid (CSF) and blood lymphocytes from patients with possible first attacks of multiple sclerosis (MS, n = 25), clinically definite MS (n = 16), and noninflammatory neurological disease control subjects (n = 30). In patients with demyelinating diseases more CSF B cells expressed CD80 than in control subjects whereas the expression of CD86 by T cells in CSF was low in patients with demyelinating disease and highly variable in the control subjects. In patients with possible first attacks of MS the expression pattern of CD80 and CD86 differed significantly between patients with or without intrathecal synthesis of IgG. Increased expression of the CD80 molecule on CSF B cells may be of importance in the pathogenesis of MS. In contrast, CSF T cell expression of CD86 may be associated with protection from MS.  相似文献   

15.
We describe here 3 patients with central nervous system infection caused by herpes simplex virus type 2 (HSV-2); one patient with brainstem encephalitis and two with recurrent transverse thoracic myelitis. All three patients showed increased IgG antibodies to HSV in the cerebrospinal fluid (CSF). HSV-2 DNA was demonstrated in the CSF by polymerase chain reaction (PCR) amplification. Upon treatment with acyclovir, one patient with myelitis partially recovered and the others completely recovered. It is important to recognize the wide spectrum of clinical manifestations of HSV-2 infection in the central nervous system (CNS).  相似文献   

16.
A method for quantitating specific anti-viral antibodies in serum and cerebrospinal fluid (CSF) is established using enzyme-linked immunosorbent assay (ELISA). Quantitated antibody levels are used to determine intrathecal specific IgG synthesis rate for the particular antibody. Measles virus was used as a model for validating this quantitative technique: a mutated form of measles virus is a cause of subacute sclerosing panencephalitis (SSPE) and there is a possibility that measles virus is related to the cause of multiple sclerosis (MS). Matched serum and CSF samples were assayed. Concentration of anti-measles IgG was determined and intrathecal measles-specific IgG synthesis rate was calculated. For the SSPE samples, measles-specific IgG synthesis rate was elevated and comprised > 20% of the total intrathecal IgG synthesis rate; these results are consistent with the literature. The ELISA method can be performed routinely, providing a quick, simple, reproducible means of quantitating specific antibody concentrations, with sensitivity greater than 1 nanogram per milliliter. With this method, quantitation of IgG antibodies to any other viral antigen can be reliably and precisely determined.  相似文献   

17.
The central nervous system is considered an early and common target for the human immunodeficiency virus type 1 (HIV-1). Serum and cerebrospinal fluid (CSF) from 20 HIV positive patients, including 14 with AIDS-dementia complex (CDC stage IV) and 6 asymptomatic individuals (CDC stage II) were analyzed by enzyme immunoassay for detection of antibodies to native myelin basic protein (MBP) and for the amino acid sequence 68-84 exposed after partial degradation of native MBP. Control groups included HIV-1 negative patients with degenerative and/or vascular dementia, chronic multiple sclerosis (MS) and individuals without any sign of neurological or cognitive disturbances. As opposed to control groups, serum and CSF samples from MS and HIV-1 infected patients showed several oligoclonal bands running in the gamma region. AIDS-dementia complex (ADC) patients had increasingly high intrathecal IgG specific antibody titers for the amino acid sequence 68-84 of MBP. Marked intrathecal antibody production for myelin components was also detected in the majority of HIV-1 infected asymptomatic individuals. Such alteration paralleled development of cognitive deficits, neurological abnormalities and appearance of CNS demyelinating plaques. Preferential immune recognition of this myelin epitope within the CSF during early stages of HIV-1 infection might point to an ongoing process of active demyelination and ultimately indicate subclinical CNS involvement.  相似文献   

18.
We compared three methods of analysis for IgG in cerebrospinal fluid, using samples from 158 patients with clinically suspected multiple sclerosis and from 200 neurological controls. The tests were: search for oligoclonal bands, calculation of rate of synthesis of IgG in the cerebrospinal fluid, and determination of the IgG/albumin ratio. Paired cerebrospinal fluid and serum samples were collected and their IgG and albumin concentrations measured. Oligoclonal bands were detected by electrophoresis on agarose. Positive results were obtained in 94, 75, and 67% of patients with probable or definite multiple sclerosis by the three respective methods. In contrast, for patients for whom the clinical diagnosis of multiple sclerosis was considered possible, positive results were obtained in 10, 43, and 13%, respectively. Evidently, detection of oligoclonal bands remains the best single test for the presence of abnormal IgG in suspected multiple sclerosis patients. A combination of the first two tests is most sensitive for both probable and definite multiple sclerosis (97%) and possible multiple sclerosis (50%). Some infectious or immunologic disorders can also produce these IgG abnormalities, but they can usually be distinguished from multiple sclerosis by other clinical and laboratory data.  相似文献   

19.
The general overexpression of p53 by different types of tumor cells suggests that p53 immunity might be generally useful for tumor immunotherapy. We describe here the induction of immunity to p53 and resistance to tumor metastasis using an idiotypic network. Mice were immunized with domain-specific anti-p53 monoclonal antibodies (Ab1): PAb-248 directed to the N-terminus; PAb-246 directed to the specific DNA-binding region; or PAb-240 directed to a mutant p53 that does not bind specific DNA. Immunized mice responded by making anti-idiotypic antibodies (Ab2) specific for the Ab1 inducer. Ab1 PAb-246 induced Ab2 that, like p53 itself, could bind the specific DNA oligonucleotide sequence of the p53 responsive element. Mice immunized with Ab1 PAb-240 or PAb-246 spontaneously made Ab3 anti-p53 antibodies that reflected the specificity of their Ab1 inducers: Ab1 PAb-246 induced Ab3 specific for wild-type p53; PAb-240 induced Ab3 specific for mutant p53. Ab1 PAb-248 induced only Ab2. The spontaneously arising Ab3 were of T cell-dependent IgG isotypes. Peptides from the complementarity determining regions of the Ab1 antibodies PAb-240 and PAb-246 could also induce Ab3 anti-p53. Finally, mice that produced Ab3 anti-p53 acquired resistance to tumor metastases. Therefore, an anti-idiotypic network built around certain domains of p53 seems to be programmed within the immune system, specific Ab2 antibodies can mimic the DNA binding domain of p53, and Ab3 network immunity to p53 can be associated with resistance to tumor cells.  相似文献   

20.
The interaction between bovine pancreatic ribonuclease A (RNase A) and its RNA substrate extends beyond the scissile bond. Enzymic subsites interact with the bases and the phosphoryl groups of a bound substrate. We evaluated the four cationic residues closest to known subsites for their abilities to interact with a bound nucleic acid. Lys-37, Arg-39, Arg-85, and Lys-104 were replaced individually by an alanine residue, and the resulting enzymes were assayed as catalysts of poly(cytidylic acid) (poly(C)) cleavage. The values of Km and kcat/Km for poly(C) cleavage were affected only by replacing Arg-85. Moreover, the contribution of Arg-85 to the binding of the ground state and the transition state was uniform---Km increased by 15-fold and kcat/Km decreased by 10-fold. The contribution of Arg-85 to binding was also apparent in the values of Kd for complexes with oligonucleotides of different length. This contribution was dependent on salt concentration, as expected from a coulombic interaction between a cationic side chain and an anionic phosphoryl group. Together, these data indicate that Arg-85 interacts with a particular phosphoryl group of a bound nucleic acid. We propose that Arg-85 comprises a new distal subsite in RNase A---the P(-1) subsite.  相似文献   

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