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PubMed1997

Determination of IgE antibodies to the benzylpenicilloyl determinant: a comparison of the sensitivity and specificity of three radio allergo sorbent test methods.

The quantitation of in vitro IgE antibodies to the benzylpenicilloyl determinant (BPO) is a useful tool for evaluating suspected penicillin allergic subjects. Although many different methods have been employed, few studies have compared their diagnostic specificity and sensitivity. In this study, the sensitivity and specificity of three different radio allergo sorbent test (RAST) methods for quantitating specific IgE antibodies to the BPO determinant were compared. Thirty positive control sera (serum samples from penicillin allergic subjects with a positive clinical history and a positive penicillin skin test) and 30 negative control sera (sera from subjects with no history of penicillin allergy and negative skin tests) were tested for BPO-specific IgE antibodies by RAST using three different conjugates coupled to the solid phase: benzylpenicillin conjugated to polylysine (BPO-PLL), benzylpenicillin conjugated to human serum albumin (BPO-HSA), and benzylpenicillin conjugated to an aminospacer (BPO-SP). Receiver operator control curves (ROC analysis) were carried out by determining different cut-off points between positive and negative values. Contingence tables were constructed and sensitivity, specificity, negative predictive values (PV-), and positive predictive values (PV+) were calculated. Pearson correlation coefficients (r) and intraclass correlation coefficients (ICC) were determined and the differences between methods were compared by chi 2 analysis. Analysis of the areas defined by the ROC curves showed statistical differences among the three methods. When cut-off points for optimal sensitivity and specificity were chosen, the BPO-HSA assay was less sensitive and less specific and had a lower PV- and PV+ than the BPO-PLL and BPO-SP assays. Assessment of r and ICC indicated that the correlation was very high, but the concordance between the PLL and SP methods was higher than between the PLL and HSA or SP and HSA methods. We conclude that for quantitating IgE antibodies by RAST to the BPO determinant, BPO-SP or BPO-PLL conjugates offer advantages in sensitivity and specificity compared with BPO-HSA. These results support and extend previous in vitro studies by our group and highlight the importance of the carrier for RAST assays.

Adult↗

PubMed1997

Defining intermediate stages in cell determination: acquisition of a lens-forming bias in head ectoderm during lens determination.

Cell determination in vertebrates requires integration of many events, although the mechanisms controlling the different stages in this process are poorly understood. While studies of lens determination have helped define some of these stages, we know very little about the intermediate steps involved in the commitment of ectoderm to lens formation. Lens determination begins during gastrulation when ectoderm is briefly competent to respond to lens-inducing signals and progresses to a point, at the neural tube stage, when the presumptive lens ectoderm is specified. Between these two stages important regulatory genes are activated in the presumptive lens ectoderm, including the transcription factor Pax-6, and transplantation experiments presented here suggest that the presumptive lens ectoderm is becoming "biased" toward lens formation. We show that competent ectoderm from Xenopus laevis embryos forms well-differentiated lenses in most cases when transplanted to the presumptive lens area of neural plate stage hosts, where the lens-inductive environment is strong. When placed into later, neural tube stage hosts, optimally competent ectoderm does form small lenses in about half the cases, but the overall response is much weaker. Even in this weakly inducing environment, however, lens ectoderm that is part way through the inductive process (at the neural plate stage) is shown to have a lens-forming bias, since it forms well differentiated lenses in nearly all cases. While we find that ectoderm surrounding the lens-forming area at neural plate stages does not have a lens-forming bias, non-lens head ectoderm at the neural tube stage does, suggesting that a large region of head ectoderm is biased during neurulation. Using Rana palustris embryos, a species used in the earliest lens induction studies, we were also able to show that the optic vesicle can induce lenses in non-lens head ectoderm at neural tube stages. These results lead us to refine the definition of lens cell determination and provide a context that should allow clarification of determination mechanisms.

Animals↗

PubMedDate not supplied

Creatine kinase and myoglobin determination in myocardial infarction (determination of infant size).

In order to evaluate the diagnostic and prognostic importance of serum myoglobin (Mb) determination during acute myocardial infarction (AMI) we determined the time of first rise of both CK and Mb, that is the time in hours between the onset of pain and the last normal myoglobin and enzyme determination (TFR for Mb = 2.2 +/- 1.5 h; TFR for CK = 4.0 +/- 2.5 h). We also attempted to evaluate infarct size by mathematical analysis of the serum concentrations of Mb. The average percentage difference between the infarct size calculated from the CK concentrations and Mb concentrations was 35.8 +/- 35.2%. The results show that the determination of serum myoglobin is a useful and sensitive test for the early diagnosis of AML. On the other hand, the serum myoglobin cannot be utilized to evaluate infarct size. The main limitation in the determination of infarct size from the serum Mb concentrations lies in the extreme variability of the disappearance rate (Kd), mainly resulting from the renal elimination of the substance.

Clinical Enzyme Tests↗

PubMed1991

Biosensor system for continuous flow determination of enzyme activities. II. Simultaneous determination of plural enzyme activities.

A biosensor system for continuous flow determination of plural enzyme activities was prepared from the combination of two pyruvate sensors, a prereactor and a flow cell. This system was applied to the simultaneous determination of lactic dehydrogenase (LDH) and glutamic-pyruvic transaminase (GPT) activities in the same sample. These enzyme activities can be determined by measuring pyruvate produced by the enzyme reactions as follows. The amount of pyruvic acid can also be determined from the amount of oxygen consumed upon oxidation of pyruvic acid by pyruvate oxidase. (Formula: see text). Therefore, both of the detectors for the determination of lactic dehydrogenase and glutamic-pyruvic transaminase activities were prepared from the combination of a pyruvate oxidase membrane and an oxygen electrode. Pyruvate oxidase was covalently immobilized on a membrane prepared from cellulose triacetate. A linear relation was obtained between the output current and LDH or GPT activities in the range of 50 to 3,600 IU l-1 or 6 to 1,000 IU l-1, respectively. Each assay of these enzyme activities was completed within 15 min. The results obtained had a precision of ca. 4%. The sensor was stable for more than 25 days at 5 degrees C.

Alanine Transaminase↗

PubMed2006

Critical aspects of the determination of pentafluorobenzyl derivatives of aldehydes by gas chromatography with electron-capture or mass spectrometric detection: Validation of an optimized strategy for the determination of oxygen-related odor-active aldehydes in wine.

This work presents a thorough study of some aspects critical to the quantitative performance of methods for the determination of volatile aldehydes previously derivatized to pentafluorobenzyl hydroxylamine oximes. The conclusions of the study are further applied to the validation of an optimized procedure for the determination of oxidation-related aldehydes from wine. Aspects studied include the chromatographic injection, the analytical performance of electron-capture detection (ECD) or MS detection, and the way in which the derivatization is carried out. Different injection techniques have been optimized and compared (classical splitless-hot injection; cold splitless; and large volume solvent split injection). All of them were carried out in a programmed temperature vaporization (PTV) injector, with a 350 microL internal volume liner (3.4 mm internal diameter). Classical splitless injection of hexane extracts is troublesome and requires large carrier gas flows (>10 mL min(-1)). Cold splitless injection was clearly superior. Large volume solvent split injection has been also optimized. ECD has been found to lack the necessary selectivity for the determination of unsaturated aldehydes in wine, although the quantitation of several minor aldehydes is possible. MS detection has proven to be superior for the determination of these compounds in wine. The way in which the reagent is applied is also critical and for the case of wine is important to ensure that the reagent is applied after some of the major wine aldehydes have been eliminated. The finally proposed method is extremely sensitive. Method detection limits ranged from 0.002 microg L(-1) (for unsaturated aldehydes) to 0.73 microg L(-1) (for phenylacetaldehyde) and precision (measured as relative standard deviation) is < or =6% in all cases. The method makes it possible to determine quantitatively in a single run the wine aldehydes with sensory significance (isobutyraldehyde, 2-methylbutanal, isovaleraldehyde, (E)-2-hexenal, (E)-2-heptenal, (E)-2-octenal, (E)-2-nonenal, methional and phenylacetaldehyde).

Aldehydes↗

PubMed2006

Continuous glucose monitoring -- a novel approach to the determination of the glycaemic index of foods (DEGIF 1) -- determination of the glycaemic index of foods by means of the CGMS.

UNLABELLED: The glycaemic index (GI) is a measure of the food power to raise plasma glucose (PG) concentration after a meal. For its determination, classical methods register the development of glucose concentration in capillary plasma or whole blood. The aim of this prospective open-label trial was to compare the GI of selected foods obtained by means of the Continuous Glucose Monitoring System (CGMS) (Minimed Medtronic, Northridge, USA) which has not been applied for this purpose until now, with the respective GI determined by a conventional method using the Glucometer Advance System (GAS) (Hypoguard, Woodbridge, United Kingdom), and to assess the advantages of each approach. METHODS: Portions of tested foods containing 50 g of carbohydrates were eaten for breakfast and for dinner after 10 and 4 h fast, respectively, by 20 healthy volunteers. Using GAS, PG-curves were constructed from 9 PG values at time 0, 15, 30, 45, 60, 75, 90, 105 and 120 min after the meal, and, using CGMS, from 25 values of interstitial fluid glucose concentration (ISFG) stored within 120 min in 5-minute intervals in CGMS memory. The GI was calculated (for GAS and CGMS separately) by dividing the incremental area under the curve for the tested food by the average area of 3 tests performed with the standard. Having excluded tests with missing glucose values, there remained 285 GAS- and 290 CGMS tests for further analysis. In each volunteer, each food was tested 3 times within one week so that 1 to 3 GI's were obtained and averaged. The GI for each tested food was calculated as the mean from the respective average GI's of 20 volunteers. The GI-variability was assessed according to the respective SD. The preference of GAS vs. CGMS in the persons tested was explored by means of a questionnaire. MS Excel and the statistical program SPSS v. 10.1 were used to analyze the data. RESULTS: The GI values (mean +/- SD) measured by GAS/CGMS were for dark chocolate 43.6 +/- 22.13 %/44.0 +/- 21.71 % (p > 0.01); for apple baby food 46.1 +/- 21.38 %/53.8 +/- 37.69 % (p > 0.01); for puffed rice squares 76.5 +/- 20.24 %/76.9 +/- 27.62 % (p > 0.01); for yogurt 43.2 +/- 20.17 %/37.7 +/- 21.55 % (p > 0.01). The GI's of dark chocolate, apple baby food and yogurt, determined by either method, were significantly lower than the GI of puffed rice squares (p < 0.01). CGMS was preferred by 12 of 20 volunteers (60 %). CONCLUSIONS: No significant difference could be seen between the GI's determined by conventional method (GAS) and by CGMS (p > 0.01). The method with CGMS is reliable and comfortable for both tested persons and investigators. Hence, it appears to become a sophisticated approach to determine the GI.

Adult↗

PubMed1984

Method to map antigenic determinants recognized by monoclonal antibodies: localization of a determinant of virus neutralization on the feline leukemia virus envelope protein gp70.

A method is presented whereby antigenic determinants recognized by specific monoclonal antibodies can be mapped to specific sites on a protein sequence with high resolution. Short DNase I-generated DNA fragments encoding portions of the protein of interest are molecularly cloned into the EcoRI site of the beta-galactosidase gene of phage lambda Charon 16 so as to obtain expression of random protein fragments as fusion proteins. The monoclonal antibody is used to screen the phage library to isolate phage expressing the specific antigenic determinant. DNA of immunoreactive phage can be analyzed rapidly and subcloned to allow DNA sequence determination. The method is generally applicable and permits antigenic determinants of functionally interesting monoclonal antibodies to be mapped and related to specific protein sequences. We have used this procedure to determine the region of the feline leukemia virus envelope protein gp70 recognized by a virus-neutralizing monoclonal antibody, cl.25. Antibody binding was mapped to a 14-amino acid region in the amino-terminal half of gp70. This region may be directly involved in an essential function of the gp70 protein, perhaps in gp70-mediated host recognition functions. Synthetic peptides derived from this region may provide useful vaccine antigens for the prevention of feline leukemia virus-associated disease in cats.

Antibodies, Monoclonal↗

PubMed1985

T cell receptors for responses to Mls determinants and allo-H-2 determinants appear to be encoded on different chromosomes.

Previous studies have shown that T cell clones specific for strong Mlsa,d determinants concomitantly display apparently random reactivity to allo-H-2 determinants. One explanation for this finding is that T cell recognition of Mlsa,d and allo-H-2 determinants is controlled by separate sets of receptors. If these receptors were chromosomally unlinked, karyotypically unstable T cell hybrids with dual reactivity for Mlsa,d and particular allo-H-2 determinants would be expected, occasionally, to lose reactivity for one set of determinants, but not the other. The results presented here provide direct support for this prediction.

Animals↗

PubMed1991

T cell determinant structure: cores and determinant envelopes in three mouse major histocompatibility complex haplotypes.

T lymphocytes recognize discrete regions on an antigen. The specificity of the T cell responses in three mouse strains of differing major histocompatibility complex (MHC) haplotype to a protein antigen, lysozyme, was analyzed using a series of peptides that walk the antigen in single amino acid steps. These peptide series were synthesized using the pin synthesis system, which was modified to allow the peptides to be cleaved from the pins into a physiological buffer free of toxic compounds. This methodology overcomes many of the problems associated with the production of peptides for screening proteins for antigenic determinants. The T cell determinants for the three strains were markedly different. This result points out the limitations of algorithms predicting determinants without reference to the MHC, and the importance of the empirical methodology. This analysis of the T cell response to lysozyme constitutes the most complete study of reactivity to a foreign protein to date and illustrates many important features of antigen recognition by T cells, e.g., presence of major and minor determinant regions. The outer boundaries of each immunogenic region, the determinant envelope, are difficult to define from recently immunized lymph nodes because of the heterogeneity in T cell recognition. However, core sequences common to all the immunogenic peptides in a continuous sequence can be easily defined.

Amino Acid Sequence↗

PubMed1993

Dominant determinants in hen eggwhite lysozyme correspond to the cryptic determinants within its self-homologue, mouse lysozyme: implications in shaping of the T cell repertoire and autoimmunity.

We have studied the mouse lysozyme (ML) peptide-specific T cell repertoire in mice of five different major histocompatibility complex (MHC) class II haplotypes. 14 ML peptides were tested in a lymph node T cell proliferation assay. Upon immunization of diverse mouse strains with native ML, there was no response to any of the ML peptides tested. However, nine peptides were immunogenic, although there was no consistent pattern of reactivity toward any peptide among these strains. Thus, an autoreactive T cell repertoire directed against cryptic self(ML)-determinants exists, and it is different in mice of different MHC haplotypes. Moreover, our results demonstrate that crypticity is MHC associated and not merely a structural attribute of the determinant. On comparison of the pattern of response of various peptides of ML and that of its foreign homologue, hen eggwhite lysozyme (HEL) in H-2k, H-2b, and H-2d strains of mice, a striking correlation was evident. The stretches of amino acid sequences of determinants within HEL that were dominant in each of these three strains, almost exactly overlapped in position with those of the cryptic ML determinants against which self-reactivity was demonstrated in the same strain. These results demonstrate that the dominance-crypticity relationship between HEL and ML resulting from differential processing of these two proteins is critical in determining the response to HEL rather than the degree of sequence difference between them. These observations have important implications in the shaping of the T cell repertoire for foreign proteins and in the pathogenesis of autoimmunity.

Amino Acid Sequence↗

PubMed1991

Extension of a minimal T cell determinant allows relaxation of the requirement for particular residues within the determinant.

The determinant recognized by a class II restricted helper T cell clone raised against a peptide corresponding to the C-terminal 24 residues of the heavy chain of influenza virus hemagglutinin (HA) was examined in detail. The sequence 309VKQNTLKL316 was identified as the minimal determinant for T cell activation but its stimulatory capacity was augmented by extension at either end. Sets of peptide analogs, in which each residue within the minimal determinant was replaced in turn by every one of the other naturally occurring amino acids, revealed either an absolute requirement for the native residue or a very limited degree of replaceability, at seven of the eight positions. Only the N-terminal residue 309V could be replaced with almost any other amino acid without loss of reactivity; in fact, substitution at this position with residues containing bulky side groups enhanced the response. The reactivity of the clone with analogs of the longer peptide 307KYVKQNTLKL316, which induces maximal levels of stimulation, revealed a very different pattern of replaceability for certain residues; in particular, the requirement for a lysine at position 310 was no longer apparent. This study presents a complete analysis of the importance of each individual residue to the integrity of a T cell determinant and provides evidence that the critical requirement for a particular amino acid at a given location may be overridden by N-terminal extension of the minimal determinant. These findings indicate that, within different homologs of the native sequence, particular residues may assume quite different roles.

Amino Acid Sequence↗

PubMed2005

Test bed for assessment of the kinematical determination of navigation systems for total knee arthroplasty. Does a limited range of motion of the hip joint influence the accuracy of the determination?

OBJECTIVE: To locate the rotational center of the hip joint, CT-less navigation systems for artificial knee-joint replacement use movements of the femur with a rigid body attached. It cannot be assumed that the hip joint provides free mobility at all times. The purpose of the present study was: 1) To build a mechanical model to assess the system's accuracy in locating the rotational center of the hip by simulating a step-wise reduction of the range of motion (ROM) of the hip joint. 2) To determine the system's resolution by assessing a critical distance between two positions of the same femoral rigid body during the process of locating the rotational center of the hip. 3) To determine the sensitivity of the navigation system to the rotation of a femoral rigid body relative to the femoral bone while locating the rotational center of the hip joint. MATERIAL AND METHODS: To assess the impact that a limited ROM of the hip joint has on the accuracy of determination of the hip joint's rotational center, a test bed was built. This enables validation of the algorithm used by a CT-less navigation system. RESULTS: In the first part of the study, it was shown that a reduction of the ROM of the hip joint to 30% of its initial value had no evident influence on the accuracy of locating the rotational center of the joint. In the second part of the study, it was determined that the limit of resolution between two spatial points of the pivoting process is between 4.4 and 8.7 cm. The third part of the study showed that the examined system rejected the determination of the hip center even when the rigid body was only rotated through 22.5 degrees . CONCLUSIONS: The results show that osteoarthritis of the hip with a limited ROM, for example, cannot be taken as a contraindication for the use of the evaluated CT-less navigation system. However, the surgeon should ensure that the pivoting of the femur is performed without hindrance within the free range of motion of the hip joint. In accordance with the vendor's recommendation, a minimum distance of 10 cm should be maintained between two spatial points. To ensure safe and unconstrained operation, the rigid body must be firmly attached to the bone and must not be dislocated.

Arthroplasty, Replacement, Knee↗

PubMed2001

The frequency of high avidity T cells determines the hierarchy of determinant spreading.

Autoimmunity often spreads in a predefined pattern during the progression of T cell-mediated autoimmune diseases. This progression has been well described in animal models and in man, but the basis for this phenomenon is little understood. To gain insight into the factors that determine this spreading hierarchy, we characterized the binding affinity of a panel of beta cell-autoantigenic peptides to I-Ag7, as well as the precursor frequency, functional avidity, and phenotype of the T cells that recognize these peptides in type 1 diabetes-prone nonobese diabetic mice. We observed that autoimmunity gradually spreads from a beta cell determinant, which had the largest precursor pool of high avidity T cells, to beta cell determinants with progressively smaller and lower avidity T cell precursor pools. This correlation between the sequential development of spontaneous T cell autoimmunity and the frequency and avidity of autoantigen-reactive T cells suggests that the extent to which T cells were negatively selected by the self-determinants is the key factor determining the spreading hierarchy.

Amino Acid Sequence↗

PubMed2005

[Determination of stability constant of zinc cysteinate by indirect determination using FAAS with ZnS].

On the bases of exploring measurement mechanism and complex compound components of indirect determination of cysteine acid by flame atomic absorption spectrometry with zinc sulfide, the stability constants of the complex compound of zinc cysteinate were studied successfully, after the numeric measurements and theoretical investigations under the best optimized acidity for the determination. In conclusion, at the best optimized acidity pH 9.7, the stability constant of alkalescence zinc cysteinate is between 2.998 x 10(30) and 3.858 x 10(30), with the average value beta w = 3.286 x 10(30) and log beta w = 30.517, and the standard deviation is 0.315 x 10(30). While the stability constant of zinc cysteinate is between 7.853 x 10(21) and 1.011 x 10(22), with the average value beta w = 8.607 x 10(21) and log beta w = 21.935, and the standard deviation is 0.315 x 10(21). It is shown that the atomic absorption spectrometry can not only be used for the determination of trace elements and the indirect determination of organic compound, but also can carry out the study of physical configuration and the determination of physical constant of complex ion.

Cysteine↗

PubMed1990

[Radioimmunologic determination of growth factors. II. Comparative development of methods for the determination of hematopoietic growth factors].

On the basis of our long-term experience, presented are the current clinically useful methods for determining erythropoietin, the granulocytopoiesis growth factor and thrombocytopoietin with the results in their use. Facts are shown, concerning the long-used method of determining erythropoietin through the use of the biological test on polycythemic mice. In our conditions, mice treated with physiological solution (negative controls) have a Fe-59 incorporation below 0.5% of the given dose, while 0.2 units of the international erythropoietin standard (positive control) increases that incorporation to 3.0%. Also presented, are results of determining erythropoietin by means of the newest immunometric method which has shown exceptional features: the whole procedure, including necessary rinsings, lasts about six hours, and it is possible, in the course of one work day, to all at once precisely determine the erythropoietin concentration in 80 samples of human serum. This fact, as well as the outstanding sensitivity of the method which is about 2 mJ/ml (that is 50 times the sensitivity of the biological test) has as a result, the wide introduction of erythropoietin determination in the clinical use of today and the definition of its clinical importance. The measurement range of the method is from 2-200 J/L which can be extended further by specimen dilution. It is especially important that duplicate measurements at one point of the curve almost coincide, which indicates great method precision. The lowest measured concentration in our series amounted to 0 J/L and the greatest to greater than 250 J/L. Elevated values were found in 17 of the 114 serums.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1989

[Cloning the genetic determinant of alpha-hemolysin and obtaining a series of insertional mutations in this determinant by the transposon Tn1000].

Functionally active genetic determinant of alpha-hemolysin was cloned. Hemolytic plasmid pHly195 was used as a donor of the determinant and pBR322 plasmid served as recipient. Cloning was done with a help of HindIII restriction endonuclease. The recombinant plasmid obtained represents pBR322 plasmid with the built-in fragment of 7.4 kb containing genes of functionally active determinant of alpha-hemolysin. Restriction map was constructed using HindIII, EcoRI, BamHI and SalI restriction endonucleases. Insertional mutagenesis was carried out with the help of the Tn1000 transposon. Plasmid DNAs were isolated from insertional mutants of Hly- phenotype and treated with EcoRI, SalI and BamHI. On the basis of the sizes of restriction fragments of the mutant plasmid DNAs localization and orientation of insertions of Tn1000 into the cloned determinant of alpha-hemolysin were determined.

Bacterial Proteins↗

PubMed1989

[Radioimmunologic determination of growth factors. I. Determination of somatomedin C].

The authors' first experience in the determination of plasma somatomedin C concentration by the radioimmunologic method without extraction was put forward. The method itself was checked up through the routine indicators and the range of normal limits was established by the determination of this concentration in the plasma of 15 healthy persons. Values of plasma and serum determination greatly differentiated. By the determination of somatomedin C concentration and growth hormone during the insulin test in 8 persons it was shown that somatomedin C concentration did not change by the abrupt and short changes in growth hormone concentration. A good correlation was made by the comparison of sometomedin C and growth hormone basal concentration in 16 samples whereby the regulatory role of growth hormone in somatomedin C excretion was confirmed. In conclusion, radioimmunologic determination of sometomedin C in diagnostics and the therapy of growth disturbance was emphasized.

Female↗

PubMed1976

Antigenic determinants of adenovirus capsids. II. Homogeneity of hexons, and accessibility of their determinants, in the virion.

We have tested the two principal theories which explain the previous finding that small amounts of type-specific antibody to the adenovirus hexon can neutralize infectivity, whereas even large amounts of cross-reactive antibody do not. a) It has been suggested that the type-specific determinants are especially prominent in the virion. We have therefore measured the capacity of whole virus to bind appropriate antibodies, using a sensitive radioimmunoprecipitation (RIP) system. In fact, virions bound type-specific and cross-reactive antibodies impartially. Moreover, they bound both much less effectively than did free hexon or disrupted virus, suggesting that many of each kind of determinant are inaccessible in virions. b) It has been suggested that the type-specific determinants are confined to those hexons located next to the pentons, and that they are the targets for neutralizing antibody. We have therefore studied the antigenicity of peripentonal and nonamer hexons isolated from virions, and found that each possessed both kinds of determinants. Furthermore, these were present in the same proportion as in hexons purified from the soluble antigens in infected cells ("free hexons"). We concluded that the mechanism of neutralization by antibody is complicated, and that the type-specific determinants exposed on the virion must play a crucial role.

Adenoviridae↗