Thermolabile Antigen Research Articles

Delayed allergic reaction to eating lemon

Lemon allergy can be caused by both IgE-mediated and IgG-dependent mechanisms, or by a combination of the two. Allergic reactions to lemon are clinically evidenced by a variety of symptoms, including digestive system disorders (cheilitis, eosinophilic esophagitis, gastroenteritis, colitis, and irritable bowel syndrome). Contact dermatitis is the only condition included among delayed allergic reactions to components of the fruit or lemon essential oils. Data on reactions to lemon and its components from the gastrointestinal tract are scarce in modern publications, and most of what is available are either a description of a single case or an analysis of the frequency of sensitization to lemon among groups of patients with allergic pathology of the digestive system.
 For the first time, a clinical instance of a simultaneous acute and delayed allergic reaction to eating a lemon, manifesting as an oral allergy condition and gastrointestinal symptoms, in a 31-year-old woman, was described. The patient was diagnosed with polysensitization to various food, household, and pollen antigens, and cross-allergy to fruits of the Rutaceae family (orange, tangerine, and grapefruit). She was diagnosed with allergy and sensitivity to the allergens in the lemon pulp after undergoing a prick + prick test and an enzyme-linked immunosorbent assay. It has been found that lemon pulp contains one or more thermolabile antigens that cause both acute and delayed allergic symptoms. It has also been demonstrated that thermolabile allergens and/or particular antigenic determinants can cause delayed allergy reactions, despite the action of proteolytic enzymes of the gastrointestinal tract and hydrochloric acid. To confirm these properties of allergenic epitopes, additional research, not limited to research on thermal effects alone, but also treatment with hydrochloric acid and enzymes, is highly recommended.
 Thus, for the first time, we have demonstrated that allergic reactions to lemon, with the accompanying gastrointestinal manifestations, are not limited to IgE-dependent or cell-mediated types of hypersensitivity. Clarification of specific mechanisms of allergy development and characteristics of epitopes of molecules that cause allergic reactions necessitates comprehensive diagnostics research that includes both laboratory methods (including molecular-based methods) and conducting provocative tests.
 Additional studies are required to determine the sensitivity of protein molecules of allergens to the effects of various factors in the gastrointestinal tract. This will enable us to further determine the resistance of individual antigenic epitopes of lemon allergens to these factors.

Newcastle disease vaccines—A solved problem or a continuous challenge?

Newcastle disease (ND) has been defined by the World Organisation for Animal Health as infection of poultry with virulent strains of Newcastle disease virus (NDV). Lesions affecting the neurological, gastrointestinal, respiratory, and reproductive systems are most often observed. The control of ND must include strict biosecurity that prevents virulent NDV from contacting poultry, and also proper administration of efficacious vaccines. When administered correctly to healthy birds, ND vaccines formulated with NDV of low virulence or viral-vectored vaccines that express the NDV fusion protein are able to prevent clinical disease and mortality in chickens upon infection with virulent NDV. Live and inactivated vaccines have been widely used since the 1950’s. Recombinant and antigenically matched vaccines have been adopted recently in some countries, and many other vaccine approaches have been only evaluated experimentally. Despite decades of research and development towards formulation of an optimal ND vaccine, improvements are still needed. Impediments to prevent outbreaks include uneven vaccine application when using mass administration techniques in larger commercial settings, the difficulties associated with vaccinating free-roaming, multi-age birds of village flocks, and difficulties maintaining the cold chain to preserve the thermo-labile antigens in the vaccines. Incomplete or improper immunization often results in the disease and death of poultry after infection with virulent NDV. Another cause of decreased vaccine efficacy is the existence of antibodies (including maternal) in birds, which can neutralize the vaccine and thereby reduce the effectiveness of ND vaccines. In this review, a historical perspective, summary of the current situation for ND and NDV strains, and a review of traditional and experimental ND vaccines are presented.

Development of an AT2-deficient proximal tubule cell line for transport studies.

Angiotensin II is a major regulatory peptide for proximal tubule Na(+) reabsorption acting through two distinct receptor subtypes: AT(1) and AT(2). Physiological or pathological roles of AT(2) have been difficult to unravel because angiotensin II can affect Na(+) transport either directly via AT(2) on luminal or peritubular plasma membranes of proximal tubule cells or indirectly via the renal vasculature. Furthermore, separate systemic and intratubular renin-angiotensin systems impart considerable complexity to angiotensin's regulation. A transport-competent, proximal tubule cell model that lacks AT(2) is a potentially useful tool to assess cellular angiotensin II regulation. To this end, AT(2)-receptor-deficient mice were bred with an Immortomouse, which harbors the thermolabile immortalization gene SV40 large-T antigen (Tag), and AT(2)-receptor-deficient [AT(2) (-/-)], Tag heterozygous [Tag (+/-)] F(2) offspring were selected for cell line generation. S1 proximal tubule segments were microdissected, and epithelial cell outgrowth was expanded in culture. Cells that formed confluent, electrically resistive monolayers were selected for cryopreservation, and one isolate was extensively characterized for conductance (2 mS/cm(2)), short-circuit current (Isc; 0.2 microA/cm(2)), and proximal tubule-specific Na3(+) - succinate (DeltaIsc = 0.8 microA/cm(2) at 2 mM succinate) and Na3(+) - phosphate cotransport (DeltaIsc = 3 microA/cm(2) at 1 mM phosphate). Light microscopy showed a uniform, cobblestone-shaped monolayer with prominent cilia and brush borders. AT(2) receptor functionality, as demonstrated by angiotensin II inhibition of ANF-stimulated cGMP synthesis, was absent in AT(2)-deficient cells but prominent in wild-type cells. This transport competent cell line in conjunction with corresponding wild type and AT(1)-deficient lines should help explain angiotensin II signaling relevant to Na(+) transport.

Antigen conformation dependence of Chlamydia trachomatis infectivity neutralization.

Chlamydia trachomatis infections cause the most common notifiable diseases in the United States, reflecting the successful adaptation of these organisms to persist in their obligate human host population. Antigenic variation of the quantitatively predominant major outer membrane protein (MOMP) is considered to play an important role in this adaptation as a means of immune evasion. The relative capacity of murine polyvalent sera produced following infection, recovery, and challenge to neutralize infectivity was highly serovar-specific and dependent upon thermolabile antigens. The structural complexity of these immunodominant antigens was mimicked by chlamydial MOMP expressed in Escherichia coli, as antibodies that neutralize infectivity by recognition of conformation-dependent antigens were specifically removed from sera following absorption using MOMP expressed in E. coli.

K‐antigens in Porphyromonas gingivalis are associated with virulence

We investigated antigens in spreading and non-spreading Porphyromonas gingivalis strains. On the basis of differences in virulence in the mouse model, 8 strains were selected for antiserum production in rabbits. Hyperimmune sera were tested by double immunoprecipitation and immunoelectrophoresis. Besides a common antigen, differences in antigenic composition were observed in the thermolabile antigens between all strains tested. Two different heat-stable antigens were found after heating at 120 degrees C. One such antigen was detected after sonication of the pellet fraction of autoclaved P. gingivalis cells. This antigen cross-reacted with 6 of the 8 immune sera. This somatic antigen was almost neutrally charged and sensitive to sodium periodate treatment, suggestive of lipopolysaccharide. A second heat-stable antigen was detected in the supernatant of autoclaved strains of W83, W50, HG184 and A7A1-28. These non-somatic antigens were strain-specific, i.e., no cross-reactivity was found with heterologous hyperimmune sera. An exception was strain W50, which had a non-somatic heat-stable antigen which was recognized by W83 antiserum. These antigens were resistant to DNAse, RNAse and proteinase-K treatment but were degraded by sodium periodate. In immunoelectrophoresis, these antigens appeared to be negatively charged. These properties are characteristics of a K-antigen, which likely represent a thermostable carbohydrate capsule. The presence of K-antigen correlates very well with the serum resistance, the low chemiluminescence, the resistance to phagocytosis and the need for opsonization with specific antibodies for complement-mediated killing of virulent P. gingivalis strains.(ABSTRACT TRUNCATED AT 250 WORDS)

Serological Studies on Leptospira Strain Ictero No. I Using Monoclonal Antibodies

In order to elucidate the full serological characteristics of strain Ictero No. I, the first strain of Leptospira isolated by Inada and Ido in 1914, 17 monoclonal antibodies against the strain were produced by cell fusion technology. The antibody-producing hybridomas were designated IMAs 1 to 17. The reactivities of the monoclonal antibodies produced by the hybridomas were determined by the microscopic agglutination test. One of the 17 monoclonal antibodies, IMA 1, reacted with strains Ictero No. I, LT 1131 and Naam, but not with other strains of the serogroup Icterohaemorrhagiae including strain RGA used in the present study. Moreover, the reactivity of the antigenic determinant of IMA 1 was inactivated by treatment at 56 C for 30 min. The 16 other monoclonal antibodies, IMAs 2 to 17, showed different reaction patterns against Leptospira strains of the serogroup Icterohaemorrhagiae. All of the 16 antibodies reacted with both Ictero No. I and RGA strains. The antigens against antibodies IMAs 2 to 17 were thermostable. The present study thus clarified the presence of a thermolabile antigen in strain Ictero No. I, and allowed correct distinction between the serotype of strain Ictero No. I and that of strain RGA using IMA 1. Therefore, we propose that strain Ictero No. I represents serovar icterohaemorrhagiae, as originally designated by Inada and Ido. Moreover, strain Ictero No. I should be designated as the type strain of Leptospira interrogans.

Restriction Fragment Length Polymorphism for the Identification of Campylobacter jejuni-Isolates

Companion animals ("pets") are occasionally carriers of organisms pathogenic for man. In the present, study fecal samples of clinically inapparent animals with direct contact to 204 patients, suffering from campylobacter enteritis, were investigated for C. jejuni or C. coli (CJC). CJC positive animals were seen in the environment of only five patients (= 2.4%). By comparison of biotypes and serotypes of thermostable and thermolabile antigens from human and animal isolates no clear epidemiological relationship could be deduced. Using chromosomal DNA of the strains, genetic identity of the isolates was studied for HaeIII-restriction fragment length polymorphism (RFLP), applying a biotinylated commercial CJ probe. The probe was found to be specific for most CJ strains and revealed a pattern of one to four bands. In contrast to biotyping no identity of patient strains and animal isolates was seen in three cases; one case with different biotypes had identical RFLP patterns; one patient CJ strain did not show any pattern with the CJ probe. Serotypes were identical for a larger number of animal strains but differed in HaeIII RFLP and vice versa. Comparing the results from the different technological approaches it seems impossible to give a clear statement on the epidemiology of campylobacter infections or carrier state by biotyping alone. It is concluded that DNA RFLP patterns are a useful additional tool, but for epidemiological analysis a set of different methods should be used.

Serological Analysis of Thermolabile Antigens ofVibrio anguillarum

Abstract Serological analysis of thermolabile antigens of representative strains belonging to the J-O-1, J-O-2, and J-O-3 serotypes of Vibrio anguillarum, which are the major serotypes of thermostable antigens (O-antigens) in Japan, showed that the strains belonging to each O-serotype possessed a common thermolabile antigen designated as k-1. In addition to the k-1 antigen, strains of the J-O-1 serotype of biovar II V. anguillarum possessed another antigen designated as k-2. These findings were confirmed by examining additional strains belonging to each O-serotype. The k-1 antigen was found in all the strains of J-O-4, J-O-5, J-O-6, J-O-7, and J-O-8 serotypes, which are minor serotypes in Japan. The same antigen was also found in some strains of V. metschnikovii, Aeromonas hydrophila, and A. salmonicida.

The effect of ethanol on cell wall antigens ofSaccharomyces cerevisiae and specific isolation of high ethanol producing strains of this yeast, making use of a serological technique

Generally, natural isolates of high ethanol producing Saccharomyces cerevisiae obtained by screening are used in alcoholic industries. The methods involved in their isolation and identification are elaborate. Antigenic analysis using antibodies raised against whole Saccharomyces cells indicated species specificity of cell wall surface thermostable antigens. By affinity purification, the specific antibodies could be obtained and used for specific isolation of S. cerevisiae. Antigenic studies using antibodies raised against isolated cell walls of fermentatively grown S. cerevisiae indicated the occurrence of thermolabile antigens common to Saccharomyces species. Higher concentrations of these antigens could be detected in those S. cerevisiae that had the ability for high ethanol production. The concentrations of these cell wall common antigens increased with increasing culture age and ethanol accumulation in culture broths. In younger yeast cells, the concentration could be increased by growing the cells in a medium containing added ethanol. Using dilutions of cross absorbed antibody specific for common antigens and Ouchterlony test, high ethanol producing S. cerevisiae could be identified.

Identification and characterization of a thermolabile antigen (TLAa, enolase) in Saccharomyces cerevisiae.

Five kinds of proteins of Saccharomyces cerevisiae were recently purified to a homogeneous state and identified as yeast cell surface antigens (TLAa, TLAb, TLAc, TLAd, and TLAe), but their physiological functions remained uncertain. In this paper, TLAa was identified as a yeast enolase (EC 4.2.1.11) from the following evidence: (1) molecular weights and amino acid compositions of both proteins were similar, (2) the N-terminal 22 amino acid sequences of both proteins were the same (3), TLAa had enolase activity, and (4) the authentic yeast enolase gave a positive reaction with anti-TLAa serum in the Ouchterlony immunodiffusion test and the immunoblotting test. Two isoproteins of TLAa (enolase) were separated by non-denatured polyacrylamide gel electrophoresis and detected by immunoblotting with anti-TLAa serum. The contents of the two isoproteins varied depending on the following culture conditions: glucose starvation, growth in the presence of non-fermentable carbon sources, and growth in media containing sodium chloride and 2-deoxyglucose. The contents did not vary, however, with heat shock treatment or with growth in media containing sodium azide, tunicamycin, or sorbitol. These results showed that TLAa was a cytoplasmic antigen, and that its synthesis was regulated by some environmental stresses.

Specificity of slide agglutination test for detecting bacterial fish pathogens

The usefulness of the slide agglutination assay for a rapid diagnosis of fish diseases was evaluated using a total of 80 pathogenic bacteria and environmental isolates belonging to the genera Vibrio (28), Pasteurella (5), Aeromonas (26), Yersinia (6), Edwardsiella (8), Pseudomonas (6) and Lactobacillus (1). Selected strains from each bacterial group were used as antigens for rabbit immunization. The specificity of the reactions between whole-cell antigens and the different whole-cell antisera varied according to the bacterial group analyzed. In the case of V. anguillarum, it was found that by using two sera against serotypes 1 and 2, it was possible to detect most of the strains causing vibriosis regardless of their origin. Cross-reactions were not detected between either both serotypes or with other pathogenic or environmental vibrios. In general, the whole-cell antisera from P. piscicida, A. salmonicida, Y. ruckeri and E. tarda detected all the strains within each species. However, a more heterogeneous pattern was exhibited by the motile Aeromonas species. The majority of A. hydrophila and A. sobria isolates did not agglutinate with the anti A. caviae serum, indicating that this antiserum is not adequate for identifying all motile Aeromonas strains. The antiserum against A. salmonicida subsp. masoucida displayed weak cross-reactions with some A. salmonicida subsp. salmonicida and A. hydrophila whole-cell antigens. Strong cross-agglutinations occurred also between types I and II of Y. ruckeri as well as between E. tarda and E. ictaluri. These cross-reactions were eliminated by using the respective thermostable somatic “O” antigens, which indicates that common thermolabile antigens are shared by these strains. The slide agglutination test, using anti whole-cell sera and two antigen preparations (whole-cells and “O” antigen) for each strain, is useful for a rapid detection of fish pathogens, with the additional advantage of its applicability for serotyping studies. Furthermore, some cross-reactions using the whole-cell antigens are reliable in identifying a wide range of strains causing similar diseases with a small number of anti whole-cell sera.

Zur Frage eines Typstammes beziehungsweise Neotypstammes für die Leptospiren

A deep review of the scientific literature concerning the history of the two oldest icterohaemorrhagiae strains is given in order to promote a decision about the legitimate neotype strain on the genus Leptospira.The strain RGA was found to meet completely the requirements for a Neotype culture given by the International Code of Nomenclature of Bacteria. Its origin from a patient with Weil's disease through guinea pig passages in 1915 is well documented and its culture is unequivocally described by Ungermann in 1916. The strain was maintained in pure culture. Since more than 60 years the strain is used for comparative investigations in classification studies in all laboratories performing such tests.At contrary the history of strain Ictero I is very incomplete. The strain was claimed by Yamamoto to be one of the strain isolated by Inada and Ido in 1915 originally designated as Yamasaki. However, the statement the maintenance of these strains because of loss of virulence was discontinued, is repeatedly mentioned in some old publications of the authors. Moreover it is reported that the strain Ictero I because of contamination with a fungus was recultivated after a passage through a splenectomized mouse, i. e. the strain was not maintained in a pure culture. Beside this it is hardly understandable why has the strain not been submitted to other laboratories before 1965.The strain Ictero I was found to contain an additional thermolabile antigen not present in RGA. At present it is impossible to decide whether this property was already present in the original culture or developed only later, eventually after its mouse passage.Summarizing all these facts, it must be stated that the strain Ictero I cannot be considered to meet all the necessary requirements of its recognition as neotype culture of the Genus Leptospira.

Biotypes, serotypes and phage types of caprine strains of Staphylococcus aureus

Nine of 11 caprine strains of Staphylococcus aureus examined belong to biotype C. They were typable serologically using antisera developed for typing human strains of Staphylococcus aureus. H2 was found to be the dominant thermostable antigen whilst 1 and 0 were the most common thermolabile antigens. Some strains possessed protein A and poly A beta (beta-glucosaminyl ribitol teichoic acid). Phage typing of the strains was achieved with an international set of phages for typing human strains of Staphylococcus aureus and they belong to phage groups II, and the mixed group.

Physicochemical and immunochemical properties of a thermo-labile antigen (TLA a) from yeast cell surface.

The physicochemical and immunochemical properties of a thermo-labile antigen (TLA a) which is located on the cell surface of Saccharomyces cerevisiae were studied. The sedimentation constant (S20,W) and molecular weight (sedimentation equilibrium method) were 6.26S and 68,800, respectively. The circular dichroic (CD) spectrum of TLA a had negative maxima at 210 and 221 nm, indicating the presence of alpha-structure of a polypeptide chain. The molar ratio of antibody to antigen which gave maximum precipitation was 2.7. Approximately 50% of the antigenic activity of heat-denatured TLA a was recovered when denatured molecules were dissolved in 6 M guanidine hydrochloride followed by 25-fold dilution with H2O. The amount of TLA a existing on the yeast cell surface was estimated to be 37.5 micrograms per 10.5 mg of fresh cells, corresponding to 0.36% by weight of the fresh yeast.

Immunochemical studies on surface of yeast cells. Part VII. Physicochemical and immunochemical properties of a thermolabile antigen (TLA b) from the yeast cell surface.

Immunochemical studies on surface of yeast cells. Part VII. Physicochemical and immunochemical properties of a thermolabile antigen (TLA b) from the yeast cell surface.

Antigen overlay technique for line immunoelectrophoresis and crossed-line immunoelectrophoresis of thermolabile antigens

A simple antigen overlay technique for line immunoelectrophoresis and crossed-line immunoelectrophoresis is described. A blind gel is overlaid with antigen-impregnated filter paper instead to mix antigens with molten agarose and to pour them in a uniform sample gel. This makes it easier in line and crossed-line immunoelectrophoresis comparison of different antigen samples, simplifying technique as compared with the conventional method. Moreover, this technique is designated to obtain reproducible patterns from thermolabile proteins since they are unaffected by being heated.

Purification and some physicochemical properties of five kinds of thermo-labile antigens from yeast cell surface.

Five kinds of thermo-labile antigens (TLA a, TLA b, TLA c, TLA d and TLA e) of yeast cell surface were isolated. Each TLA was homogeneous on polyacrylamide gel electrophoresis. The molecular weights of TLA a, TLA b, TLA c, TLA d and TLA e were 68,000, 86,000, 68,000, 170,000 and 82,000, respectively, as estimated by gel filtration on Sephadex G-200. When gel electrophoresis was performed in 0.1% sodium dodecyl sulfate (SDS), TLA a, TLA b, TLA c and TLA e gave a single band of molecular weight at about 62,000, 38,000, 33,000 or 79,000 in each test, whereas TLA d gave two bands of molecular weights at about 81,000 and 40,000. Among the five kinds of antigens, only TLA e contained 9.7% sugar, the other antigens containing no sugar moiety. TLA a, TLA c, TLA d and TLA e did not give a precipitin line against anti-TLA antisera when heated at 70°C for 10 min, whereas TLA b lost antigenicity by heating at 90°C. the isoelectric points for the five kinds of antigens were at pH 6.4 (TLA a), pH 6.1 (TLA b), pH 5.2 (T...

Immunogenicity of some common thermolabile surface antigens of Escherichia coli.

The development in rabbits of antibodies against common thermolabile Escherichia coli surface antigens - and against O and K antigens - was investigated. Three strains, E3b (O75:K95:H5), E56b (O8:K27:H-), and H61 (O45:K1:H10), and five rabbits per strain were used. Immunization was carried out by routine procedures using non-heated whole cell vaccines. Homologous and heterologous reactions were recorded. Bacterial agglutination showed no great differences between homologous antisera. Maximum agglutination titers were reached after three immunizations, i.e., 12 dyas after the first immunization. The development of antibodies to the many single common and specific antigens was followed by examination in crossed immunoelectrophoresis (CIE). Indication of immune tolerance of polysaccharide K27 antigen was found. The finding of pre-immune antibody and the rapid response to immunization indicate that many of the reactions recorded should be regarded as secondary responses. Several antigens in the three strains were identical or serologically related. The common cross-reacting thermolabile surface antigens showed similar electrophoretic mobility in the three stains. Some rabbits were found to be overall good producers of antibodies and some were poor. The occurrence or absence of pre-immune antibody to common antigens could not be sued to select the good antibody producers. It is suggested that the immune response to the common surface antigens that could be reckoned as outer membrane proteins may influence the relationship between host and bacterium.

Purification and properties of a thermo-labile antigen from baker's yeast cells.

A thermo-labile antigen (TLA) on the yeast cell surface was isolated from a yeast cell autolyzate and purified to a homogeneous state by chromatography on an immunoadsorbent affinity column. The molecular weight of TLA was about 1.45 x 105 on SDS-polyacrylamide gel electrophoresis and about 1.5 x l05 on gel chromatography on Sephadex G-200. The TLA contained 74.5% protein and 25.5% sugar. It was characterized by high contents of glycine, glutamic acid, serine and aspartic acid. Half-cystine, methionine, histidine and arginine were not found. The sugar moiety was composed of galactose, mannose, N-acetylglucosamine and fucose. The antigenic determinant of TLA was distinct from that of cell wall mannan in the Ouchterlony immunodiffusion test. No precipitin line against anti-TLA serum was observed, when TLA was heated at 90°C for 10 min. Oxidation with periodate had little effect on antigenicity, but digestion with Pronase or treatment with protein denaturants resulted in loss of the antigenicity. These resul...

Studies on the Taxonomy and Serology of Causative Organisms of Fish Vibriosis

Taxonomic studies were performed on two hundred nineteen bacterial isolates from eleven species of fish affected by vibriosis reared in fresh water or sea water all over Japan. First, we tried to identify these strains according to Bergey's Manual, 8th ed. (1974). Vibrio anguillarum and related organisms, accounting for about 90% of the strains tested, were confirmed to be causative organisms of vibriosis. Then we attempted to clarify the relationship of these organisms by numerical taxonomy with 103 representative strains. Eighty-nine of the 103 strains were classified into five major taxons (phenon I-V) with similarities of ≥ 80%. Phenon I was comprised of 64 strains identified as V. anguillarum. Phenon II contained 16 strains of Vibrio sp. (corresponding to V. ordalii by SCHIEWE et al., 1981). All of the organisms in phenon II were isolated from salmonidae reared in fresh water. Phenons III and IV consisted of the two reference strains of V. metschnikovii and five of V. parahaemolyticus, respectively. Phenon V contained two strains which were isolated from the anchovy (Eugraulis japonica) and the yellowtail (Seriola quinqueradiata). Fourteen single member-clusters belonged to other species or genera. Next, we examined the DNA-DNA homology among representative strains of each phenon, and between the five phenons and the six single member-clusters. From the results, we confirmed that phenons I and II differed from phenons III, IV, V and the single member-clusters. According to the numerical taxonomy, we considered phenon I to be clearly different from phenon II with similarities of less than 57%; however, the results of the DNA-DNA homology indicated that the two phenons probably belonged to the same species. Subsequently, we carried out a serological analysis of thermostable and thermolabile antigens of the V. anguillarum of phenon I and phenon II with additional isolates. The results showed that with thermostable antigens V. anguillarum could be separated into eight serological groups (J-O-1-J-O-8). However, more than 90% of them were classified as J-O-1-J-O-3. Furthermore 80% of the strains belonging to J-O-1 were isolated from fish reared in fresh water and more than 80% of the strains in J-O-3 were isolated from fish reared in sea water. The sources of the strains belonging to J-O-2 were not specified. There was only one strain belonging to each of J-O-4, J-O-5, J-O-6 and J-O-7, but all of them were isolated from diseased fish. So these strains are worthy of notice in relation diagnosis and prevention against fish vibriosis in Japan. The strains belonging to J-O-8 were isolated from the sea environment only, and were only slightly virulent. Their existence in the fish culture environments is interesting in regard to the epidemiology of fish vibriosis. The V. anguillarum of phenon II, which were all isolated from salmonidae reared in fresh water, possessed a common thermostable antigen (J-O-1) with the V. anguillarum of phenon I. Therefore they could not be distinguished from the V. anguillarum of phenon I by serotyping using the thermostable antigen. However, we found that they could be distinguished by a thermolabile antigen. We also found that all of the V. anguillarum (phenons I and II) possessed a common thermolabile antigen.