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PubMed1995

Characterization of high velocity oxy-fuel combustion sprayed hydroxyapatite.

Bioceramic coatings, created by the high velocity oxy-fuel combustion spraying of hydroxyapatite (HA) powders onto commercially pure titanium, were characterized in order to determine whether this relatively new coating process can be successfully applied to bioceramic coatings of orthopaedic and dental implants. Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy were used to characterize both the HA starting powders and coatings. A 12 wk immersion test was conducted and the resulting changes in the coatings were also characterized. Calcium ion release during dissolution was measured with flame atomic absorption during the first 6 weeks of the immersion study. A comparison of powder and coating X-ray diffraction patterns and lattice parameters revealed an HA-type coating with some loss in crystallinity. Fourier transform infrared results showed a partial loss of the OH- group during spraying, however the phosphate groups were still present. Scanning electron microscopy analysis showed a lamellar structure with very close coating-to-substrate apposition. The coatings experienced a loss of calcium during the immersion study, with the greatest release in calcium occurring during the first 6 days of the study. No significant structural or chemical changes were observed during the 12 wk immersion study. These results indicate that the high velocity oxy-fuel process can produce an HA-type coating; however, the process needs further optimization, specifically in the areas of coating-to-substrate bond strength and minimization of phases present other than HA, before it would be recommended for commercial use.

Aerosols↗

PubMedDate not supplied

Characterization of pre- and postjunctional receptors for neurokinins and kinins in the rat vas deferens.

Neurokinins and kinins are potent stimulants of the rat vas deferens: they increase both the twitch response to electrical stimulation by facilitating transmitter release and the basal tone of the preparation by activating smooth muscle receptors. The two sites of action have been studied separately in the present experiments by using the prostatic for the prejunction site and the epididymal section of the vas deferens for the postjunction site. Receptors for neurokinins, characterized by the order of potency of agonists, appear to be of the NK-A type both at the pre- and postjunction level. Receptors for kinins are present also at both sites and are probably of the B2 type: they have been characterized by the use of agonists and, the B2 postjunction type has been convalidated with antagonists. These compounds could not be used for the prejunction receptor characterization, because they act as agonists. Receptor for angiotensin at the prejunction level are of the same type as in the cardiovascular and other systems.

Animals↗

PubMed1992

Novel monoclonal antibodies to cyclosporine A: characterization and epitope mapping with cyclosporine analogs and cyclophilin.

Monoclonal antibodies to cyclosporine A (Cs), a potent immunosuppressant, were generated in BALB/c mice using a novel antigen prepared by linking Cs to a protein carrier via a photoactive cross-linking reagent, 4-benzoylbenzoic acid (BBa). Twenty-two monoclonal anti-Cs antibodies were generated, using Cs-BBa-bovine serum albumin (Cs-BBa-BSA) as the immunogen. They were characterized with respect to affinity by Scatchard analysis of a radioimmunoassay (RIA), and with respect to specificity by an ELISA in which a series of singly substituted Cs derivatives were examined as inhibitors. McAb affinities ranged from 5 x 10(-8) M to 2 x 10(-10) M. Based on ELISA inhibition data with Cs analogs, and on the binding to two Cs-BSA conjugates in which opposite sides of the Cs molecule are exposed, the antibodies fell into five epitope recognition groups. Binding to Cs was also studied by ELISA in competition with cyclophilin (CyP), a Cs-binding protein whose epitope specificity has been well characterized. Competition by CyP was found to correlate with antibody specificity, not with affinity, i.e. CyP competed best with antibodies having specificities most similar to that of CyP. Epitope mapping can, therefore, be accomplished in a system in which two different species of binding proteins compete for the same antigen. This type of characterization may be useful in identifying antibodies whose combining sites mimic those of a receptor.

Amino Acid Isomerases↗

PubMed1995

Molecular cloning and characterization of human thyroid peroxidase autoantibodies of lambda light chain type.

IgG class thyroid peroxidase (TPO) autoantibodies with kappa light (L) chains predominate in serum and the genes for a large repertoire of such autoantibodies have been characterized. The present study was performed to clone and characterize TPO autoantibodies with lambda L chains which comprise approximately 20% of serum TPO autoantibodies. From a combinatorial IgG H/lambda L chain cDNA library in the phage display vector pComb3, 24 TPO-binding clones with lambda L chains were isolated, comprising three different heavy (H) and light (L) chain combinations. These combinations utilized two genes from the Vlambda II and IIIb families (closest germline genes DPL11 and hsigg11150) and three genes from the VH1, VH3 and VH4 families (VH26, 4.34 and hv1L1). The deduced amino acid sequences of these H chains were quite different from those of kappa F(ab) isolated using the same H chain library. We expressed the proteins for these three lambda F(ab), as well as for a lambda F(ab) (Humlv318 L chain/DP10-like H chain) previously isolated from another patient. The affinities for TPO of the lambda F(ab) (Kd 8 x 10(-10) M to 10(-7) M) were lower than those of the kappa F(ab) (Kd approximately 10(-10) M). For two lambda F(ab), both H and L chain genes were close to germline configuration, but there was no straightforward relationship between the extent of somatic mutation from germline configuration and affinity for TPO. All four lambda F(ab) bound less well to denatured TPO as to native TPO. The three F(ab) for which sufficient protein could be expressed for competition studies all recognized domain B within the immunodominant region on TPO previously identified using F(ab) with kappa L chains. Aside from these TPO-specific F(ab), only a few other human IgG class, organ-specific autoantibodies with lambda L chains have been characterized at the molecular level. Our study significantly augments the small database on this category of autoantibodies in general.

Amino Acid Sequence↗

PubMed1995

Characterization of the variable regions of a chimpanzee monoclonal antibody with potent neutralizing activity against HIV-1.

The variable (V) regions of C108G, a potent neutralizing chimpanzee mAb against a glycan-dependent epitope in the V2 region of HIV-1 gp120, have been characterized for reactivity with human VH and VK family-specific antisera, and their nucleotide sequences have been determined and analysed. To our knowledge, this is the first study characterizing expressed chimpanzee VH and VK genes. Results show that C108G expresses members of the VH3 and VK1 families, the largest VH and VK families in humans, respectively. Nucleotide and amino acid sequence analyses reveal that C108G VH is most homologous to the human VH3 germline gene, hsigdp33 or V3-43, and the human JH4 minigene. The human germline VK1 gene that is most homologous to C108G VK, hsigk1012, was previously observed in unmutated form in a human autoantibody with anti-i red blood cell antigen specificity and in seven human Fabs and a mAb directed against epitopes overlapping the CD4-binding site of HIV-1 gp120. This germline gene was unmutated in three of the human Fabs and was somatically mutated in the other four Fabs and the mAb. In addition, the JK minigene was used in C108G VK, JK2, is apparently over-represented in anti-HIV-1 mAbs/Fabs; this minigene was used in 61% of the anti-gp120 human Fabs recently described and in three other anti-CD4-binding site human mAbs derived by EBV transformation. While the significance of these findings is unclear, they may suggest a bias in VK/JK gene usage and/or network regulation involving an hsigk1012/JK2 idiotope(s) in the antibody response to HIV-1. Both the C108G VH and VK genes showed evidence of somatic mutation and antigen selection that apparently occurred in vivo during chronic exposure to HIV-1 and its antigens. Surprisingly, this somatic mutation was most profound in the CDR3 region of C108G VK; this region shared only 48% nucleotide homology with hsigk1012 contrasted with a homology of 94% over the remainder of these two V gene sequences. Perhaps the most significant finding of this study is that the expressed VH and VK genes of chimpanzee mAb C108G are no more divergent from their most homologous human germline genes than are the expressed V genes of several recently characterized human anti-HIV-1 mAbs/Fabs from their apparent human germline genes. This suggests that chimpanzee mAbs are no more likely to elicit deleterious anti-immunoglobulin responses in humans than are human mAbs and emphasizes the potential for development of chimpanzee mAbs as immunotherapeutic agents.

Amino Acid Sequence↗

PubMed1983

Formation of asymmetrical planar lipid bilayer membranes from characterized monolayers.

A device allowing the formation of lipid bilayers by apposition of characterized monolayers has been designed and constructed. It is essentially composed of two solid Teflon Langmuir troughs, pressed along one another. The troughs are both equipped with a movable barrier for the compression of the monolayers and a float-type torsion balance for the detection of the surface pressures. The lipid bilayers are formed across a tiny hole (0.225 mm diameter) punched through a polymer film clamped in between the two troughs and are characterized by their electrical properties (specific resistance and capacitance). Experimental results have been obtained on asymmetrical membranes of phosphatidylethanolamine and phosphatidylserine formed from monolayers and from lipid films many molecular dimensions in thickness. Two polymer supports, Teflon and polypropylene, were used and coated with either squalene or petroleum jelly. The results show that the stability of the bilayer, particularly when formed from monolayers, is a direct function of the interactions of the lipids with the coated support. The most stable membranes are obtained when Teflon is used as support and squalene as coating. The most important advantage of the technique presented here is found when the bilayers are formed from mixtures of components deposited at the interface. Indeed, our system allows a characterization of the miscibility of the components in the monolayers prior to form the membrane, as opposed to a complete ignorance of the molecular organization when the bilayers are formed by apposing lipid films.

Chemical Phenomena↗

PubMed1992

Identification and characterization of rat intestinal lamina propria cells: consequences of microbial colonization.

Germ-free (GF) animals exhibit an abnormally diminished, cell-mediated immune response which can be rapidly normalized by bacterial colonization of the intestine. This conventionalization suggests that the development and/or regulation of the immune system is dependent upon intestinal bacteria or their products. Here we consider the ontogeny of gut-associated lymphoid tissue (GALT) immunocytes by isolating and characterizing the intestinal lamina propria cells (LPC) of GF rats responding to bacterial colonization or an irrelevant protein antigen, and compared to LPC of specific pathogen-free (SPF) rats which were conventionalized (CV) from birth. Isolation of cells was accomplished by successive EDTA washings of small intestine to remove the epithelium, and enzymatic digestion of the tissue generating single-cell suspensions. Resulting cell suspensions were characterized by monoclonal antibodies directed against leukocyte epitopes using flow cytometry. Functional characterization was measured by the tritiated thymidine proliferation assay with concanavalin A (Con A) and lipopolysaccharide (LPS) as co-stimulators. Germ-free and SPF rats had fewer total LPC than CV rats. Antibody staining revealed that GF rats had fewer total leukocytes than CV and SPF rats, and that CV rats had a greater percentage of T-cells and cells positive for the C3 receptor than GF rats. Co-stimulation of LPC with mitogens only increased proliferation of cells from CV rats compared to GF and SPF rats. In addition, spleen cells from CV rats demonstrated significantly enhanced proliferative responses compared to spleen cells from GF rat and were more analogous to spleen cells from SPF rats in their ability to proliferate in vitro, with and without mitogens. We conclude that T-cells and CD35-positive (C3BR+) cells are recruited and/or proliferate in response to intestinal bacteria and/or their products, and that this results in the induction of immune competency.

Animals↗

PubMed1991

1H-NMR characterization of cucumber peroxidases.

Two peroxidase isoenzymes from Cucumber seedlings, one acidic (pI = 4) and one basic (pI = 9), were characterized by 1H-NMR spectroscopy. The NMR spectra were obtained in the native (ferric high-spin) and cyanide ligated (ferric low-spin) forms of both isoenzymes. The NMR spectral comparison of paramagnetically shifted resonances with those of the well characterized horseradish peroxidase C, HRP(C), isoenzyme indicates that both cucumber peroxidases have a protohemin IX prosthetic group with proximal histidine coordinated to the heme iron. The downfield heme 1H-NMR shift pattern is distinct for each isoenzyme, and this reflects presumably dissimilar heme active site environments. The basic isoenzyme shows less asymmetry in heme 1H-NMR signals as compared to the acidic isoenzyme or HRP(C) isoenzyme. It was also found that the acidic cucumber peroxidase exists predominantly as a monomeric species in solution with 30 kDa molecular mass as opposed to its earlier characterization as a 60 kDa dimeric protein.

Binding Sites↗

PubMed1993

Characterization of Serratia marcescens nuclease isoforms by plasma desorption mass spectrometry.

Isoforms of Serratia marcescens nuclease found in the natural nuclease produced by S. marcescens and in recombinant nuclease produced by Escherichia coli were structurally characterized by peptide mapping using plasma desorption mass spectrometry. The nuclease isoforms produced and secreted from S. marcescens B10M1, which are present in much greater amounts than in S. marcescens W225 nuclease produced by E. coli, were characterized completely and the information used to facilitate characterization of the recombinant nuclease isoforms. After purification of the nuclease the isoforms were separated on a DEAE-cellulose anion-exchange column and then digested with endoproteinase Lys-C. The peptides generated were isolated by reverse-phase HPLC and their molecular masses determined by plasma desorption mass spectrometry. Comparison of the peptides from the native nuclease, Sm2, and the two isoforms, Sm1 and Sm3, revealed that they differed only in the N-terminus, the latter being found to lack three amino acids in Sm1 and one amino acid in Sm3. No interior post-translational changes were found in either of the three isoforms. Using this information we were able to confirm that Sm1, the isoform lacking three amino acids, was also present in very small amounts in recombinant S. marcescens W225 nuclease produced and excreted by E. coli.

Amino Acid Sequence↗

PubMed1994

Physico-chemical characterization of products of unfolding of cytochrome c by calcium chloride.

Cytochrome c (cyt c) denaturation by calcium chloride (CaCl2) and guanidine hydrochloride (GdnHCl) denaturation in presence of low fixed concentrations of CaCl2 has been carried out by UV/Vis spectrophotometry at pH 7.0 and 25 degrees C. The unfolding process was followed by measuring changes in difference molar extinction coefficient around 400 nm and delta epsilon 290. The products of denaturation were further characterized by intrinsic viscosity ([eta]) measurements. It has been observed that the reversible unfolding of cyt c by CaCl2 occurs in two distinct stages or involves three species (or states) namely N<-->X<-->D. Characterization of the native state, N intermediate state, X and the end product, D suggests that (i) During N<-->X only heme is exposed and no secondary structure unfolding occurs so that X state remains as compact as the native state. (ii) Stage X<-->D shows the melting of secondary structure. (iii) The end product corresponds to a random coil. and (iv) Thermodynamic characterization of the end product shows that heme plays an important role in the stability of the protein and removal of heme will lead to the unfolding of cyt c. Mixed denaturation shows a highly cooperative reversible transition between the native and denatured conformation. Analysis of the mixed results shows that (1) Gdn+ does not have any binding site (s) on the native cyt c, (2) there is one binding site for Ca2+ which stabilizes the protein, and (3) the binding constant, ks, is 5 M-1 for Ca2+.

Calcium Chloride↗

PubMed1986

Characterization of benzodiazepine receptors in the bovine pineal gland: evidence for the presence of an atypical binding site.

Bovine and rat pineal benzodiazepine receptors were characterized using ligands with high affinities for either 'central-type' (CBR) or 'peripheral-type' (PBR) benzodiazepine receptors. The characteristics (Bmax = 83 +/- 10 fmol/mg protein, Kd = 3.88 +/- 0.46 nM) of benzodiazepine receptors in bovine pineal membranes measured with [3H]flunitrazepam (using flunitrazepam to define non-specific binding) were consistent with previously reported values. However, if non-specific binding was defined using Ro 15-1788 (a selective CBR ligand), the Bmax and Kd of [3H]flunitrazepam decreased 51 and 58%, respectively. In addition, when using PK 11195 to determine non-specific binding, the Bmax of [3H]flunitrazepam binding to bovine pineal decreased further (approximately 80%, Kd decreased approximately 39%). Together, these observations strongly suggested the presence of PBR in the bovine pineal. Bovine pineal PBR characterized with [3H]PK 11195 revealed a high density (relative to CBR) of high affinity binding sites (Kd = 1.08 +/- 0.30, Bmax = 776 +/- 33.0 fmol/mg protein). In contrast, when [3H]Ro 5-4864 (1-20 nM) was used to define PBR, no binding was detectable. These observations are in sharp contrast to the rat pineal gland, in which both [3H]Ro 5-4864 and [3H]PK 11195 bind to a large number of PBR with high affinity (Kd approximately equal to 1.9 nM, Bmax approximately equal to 26 pmol/mg protein). Bovine pineal PBR were further characterized with compounds structurally related to either Ro 5-4864 or PK 11195.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMedDate not supplied

Urotensin I- and CRF-like peptides in Catostomus commersoni brain and pituitary--HPLC and RIA characterization.

Two distinct neuronal systems, containing urotensin I-like immunoreactivity (UI-LI) and CRF-LI respectively, have previously been demonstrated immunocytochemically in the brain and pituitary of the teleost Catostomus commersoni. In the present studies, we used HPLC followed by UI- and CRF-RIA to further characterize these UI- and CRF-LI substances. HPLC of Catostomus brain extracts (including extracts modified by dilute H2O2 oxidation or dilute acid cleavage) suggests that the major form of brain UI-LI is very likely identical to the previously characterized urophysial UI; the small amount of pituitary UI-LI is not yet fully characterized. The behavior of brain CRF-LI on reversed phase (RP) extraction suggests that it may exist largely in precursor form. Pituitary CRF-LI, however, behaved as expected for a peptide on RP extraction, and eluted from HPLC as essentially a single (though somewhat broad) peak. The HPLC behavior of pituitary CRF-LI, and its crossreactivity with various CRF antisera, suggest that it represents authentic fish CRF, apparently similar to (but not identical with) human/rat CRF.

Animals↗

PubMed1995

Molecular characterization of calcitonin gene-related peptide (CGRP) in a rat medullary thyroid carcinoma cell line.

The rat medullary thyroid carcinoma cell line, CA-77, is known to express the calcitonin gene and the cell line has been used for characterization of procalcitonin. The present investigations concentrate on a molecular characterization of the calcitonin gene-related peptide (CGRP) expressed by a subclone of this cell line. The investigations demonstrate that this subclone produces significantly more CGRP compared to calcitonin. Gel chromatography of cell extracts demonstrates heterogeneity for both CGRP and calcitonin, but a significant amount of immunoreactivity elutes corresponding to the elution position for synthetic CGRP and calcitonin, respectively. The gel chromatogram for CGRP demonstrates four immunoreactive peaks with Kd of 0.42, 0.53, 0.68, and 0.85. The immunoreactive peak with Kd 0.42 elutes corresponding to synthetic rat CGRP. The four immunoreactive peaks were characterized by high pressure liquid chromatography followed by sequence analysis and mass spectrometry. The immunoreactive peak with Kd 0.42 was identified as rat alpha-CGRP as was the peak with Kd 0.53. The peak with Kd 0.68 was identified as 19-37 rat alpha-CGRP and the peak with Kd 0.85 as 28-37 rat alpha-CGRP. In summary, we find that the CA-77 cell line expresses large quantities of normally processed amidated alpha-CGRP and specific fragments thereof. However, the cell line does not express detectable levels of rat beta-CGRP. The findings indicate that the CA-77 cell line can be useful for studies of calcitonin/CGRP gene expression.

Amino Acid Sequence↗

PubMed1993

Characterization of 4AOHW cell line panel including new data for the 10IHW panel.

There will be a continuing need for well characterized panels of EBV-transformed lymphoblastoid cell lines. Selection of the 4AOH panel was based on prior MHC typing and was intended to ensure representation of ancestral haplotypes from various racial groups. Cells from nonhuman primates, bone marrow donor-recipient pairs, and patients with IDDM were included. Selected cells from the 10IHW were included to enable further characterization. Cells were distributed to participants in the 4AOHW and were typed at multiple loci by a variety of procedures. Non-HLA genes such as TNF were included. Since the cells were distributed "blind" with hidden replicates, it was possible to evaluate the quality of the typing data. An approach to data management is described. The best current estimates of the typing of these cells are presented. The panel will be useful since it provides standards for most alleles at most loci. Since the cells are so well characterized, they represent a useful resource for MHC sequencing and for the evaluation of new typing procedures.

Alleles↗

PubMed1993

Characterization of membrane sugar-specific receptors in cultured high endothelial cells from mouse peripheral lymph nodes.

The culture of specialized high endothelial cells (HEC) from lymphoid organs (peripheral lymph nodes (PLN) and Peyer's patches (PP)) was undertaken in order to study and characterize the cell surface molecules which are involved in lymphocyte recognition and allow homing. Cells were stimulated in vivo by a graft versus host (GVH) type of reaction before isolation and culture. The resulting adherent and growing cells were characterized as endothelial cells because of their typical aspect and their ability to produce angiotensin-converting enzyme and factor VIII-related antigen. They possess tissue-specific endothelial addressins. MECA 79 antigen is present on cells isolated from PLN while MECA 367 antigen is detected on cells from PP. Surface receptors for glycans were studied cytochemically using neoglycoproteins and fluorescence microscopy and quantified by flow cytometry experiments which showed that the specificity of sugar receptors depends upon endothelial cell origin. Indeed, sugar receptors for alpha-L-fucosyl residues were specifically expressed by endothelial cells from PLN. These receptors were inducible upon action of activated lymphocyte-conditioned medium. Further characterization of endothelial cells from peripheral lymph nodes indicates that they indeed mediate adhesion of lymphocytes in vitro. The role of protein-sugar interactions in this process was assessed by inhibition experiments performed with the help of neoglycoproteins. Best inhibitory effects were obtained when endothelial cells had been preincubated with alpha-L-fucosyl-BSA and when lymphoid cells were preincubated with beta-D-galactosyl-BSA. Concomitant inhibition assays indicate the participation of sugar specific receptors--endogenous lectins--on the surface of both endothelial and lymphoid cells to achieve recognition and adhesion.

Animals↗

PubMed1990

A method for the characterization of foldings in protein ribbon models.

The ribbon model of chain macromolecules is a useful tool for analyzing some of the large-scale shape features of these complex systems. Up to now, the ribbon model has been used mostly to produce graphical displays, which are usually analyzed by visual inspection. In this work we suggest a computational method for characterizing automatically, in a concise and algebraic fashion, some of the important shape features of these ribbon models. The procedure is based on a graph-theoretical and knot-theoretical characterization of three well-defined projections of a space curve associated with the ribbon. The labeled graphs can be characterized by the handedness of the crossovers in the ribbon that are the vertices of the graph. The method can be used to provide a fully algebraic representation of the changes occurring when a molecule, such as a protein, undergoes conformational rearrangements (folding), as well as to provide a shape comparison for a pair of related molecular ribbons. This algebraic representation is well suited for easy storage, retrieval, and computer manipulation of the information on the ribbon's shape. Illustrative examples of the method are provided.

Computer Graphics↗

PubMed1991

Implementing knot-theoretical characterization methods to analyze the backbone structure of proteins: application to CTF L7/L12 and carboxypeptidase A inhibitor proteins.

In this work we apply a recently developed method for characterizing the shape of the tertiary structure of proteins. The approach is based on a combination of graph- and knot-theoretical characterizations of Cartesian projections of the space curve describing the protein backbone. The proposed technique reduces the essential shape features to a topologically based code formed by a sequence of knot symbols and polynomials. These polynomials are topological invariants that describe the overcrossing and knotting patterns of curves derived from the molecular space curve. These descriptors are algorithmically computed. The procedure is applied to describe the structure of the carboxy terminal fragment of the L7/L12 chloroplast ribosomal protein (CTF L7/L12) and the potato carboxypeptidase A inhibitor protein (PCI), which has a set of three disulfide bridges. In the former case, we describe the protein's shape features in terms of its alpha-helices, and a backbone simplified by considering helices without internal structure. An extension of the methodology to describe disulfide bridges is discussed and applied to PCI. Changes in the knot-theoretical characterization due to possible uncertainties in the resolution of the X-ray structure, as well as the inclusion of low-frequency motions of the backbone, are also discussed.

Carboxypeptidases↗

PubMed1994

Morphological and biochemical characterization of influenza vaccines commercially available in the United Kingdom.

Four vaccines are available in the United Kingdom against influenza virus. All are subunit vaccines, defined as either split-virion or purified surface antigen vaccine; there are two of each distinct type available. Both vaccine types are less reactogenic than whole inactivated virus, with antigenicity induced by viral surface glycoproteins. Here, each of the four vaccines has been characterized by electron microscopy and SDS-PAGE analysis, giving a unique vaccine profile. Three vaccines contain internal viral nucleoprotein which, in the presence of residual haemagglutinin, may induce an influenza A virus cross-reactive cytotoxic T-cell response and thus be of value to vaccine efficacy. Residual lipid was present in three vaccines and recent evidence suggests that pyrogenicity is correlated with the presence of viral lipid with clusters of surface glycoproteins. By a combination of electron microscopic evidence and biochemical characterization, it has been possible to resolve compositional differences, not only between vaccine type, but also between each individual currently available vaccine. Hence, there is the possibility that the morphological differences characterized here may be contributory to potential reactogenic effects subsequent to vaccination.

Blotting, Western↗