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PubMed1980

Human monoclonal macroglobulins with specificity for Klebsiella K polysaccharides that contain 3,4-pyruvylated-D-galactose and 4,6-pyruvylated-D-galactose.

Two human IgM myeloma proteins, IgMWEA and IgMMAY, were found to react with agar and Klebsiella polysaccharides that contain pyruvylated D-galactose (DGal). Quantitative precipitin data and precipitin inhibition studies with methyl alpha- and beta-glycosides of 4,6-pyruvylated-D-galactose showed their combining sites to be different, although each was directed against the pyruvylated-D-Gal, one reacting most specifically with Klebsiella polysaccharides with terminal nonreducing beta-linked 2,4 pyruvylated-D-Gal, whereas the other reacted equally well with Klebsiella polysaccharides that contain 3,4 beta-linked and 4,6 alpha-linked terminal nonreducing pyruvylated-DGal. Inhibition studies showed that both sites are directed toward one of the two space isomers of 3,4- or 4,6-pyruvylated DGal, the form in which the methyl group of the pyruvate is equatorial, or endo, and its carboxyl group axial, or exo, to the plane of the acetal ring. Coprecipitation studies showed the combining site of IgMWEA to be located on an (Fab')2 fragment and not on the (Fc)5mu fragment. The monoclonal peak in the serum of IgMMAY was specifically precipitated by Klebsiella polysaccharide. Myeloma proteins with specificities of this type may occur with reasonable frequency in humans and may be a consequence of clonal expansion from inapparent infection, carrier states, or disease produced by various Klebsiella organisms.

Adult↗
PubMed1983

Combining site specificities of mouse hybridoma antibodies to dextran B1355S.

The combining sites of 12 mouse hybridoma antibodies to dextran B1355S have been characterized by quantitative precipitin assay. All antibodies preferentially bind the immunizing antigen B1355S and two other class I dextrans, B1498S and B1501S, but show substantial differences in the extents to which they cross react with class I dextrans, suggesting their clustering into five groups. Three myeloma proteins, CAL20 TEPC1035, J558, and MOPC104E, which bind dextran B1355S, each fall into a different group. There appears to be a substantial, but imperfect, correlation of DH region structure and individual idiotypic determinants with dextran binding patterns. Proteins with RY DH segments and IdI (J558) idiotypes are in groups 1 or 3, and proteins with YD DH segments and IdI (MOPC104E) idiotypes are exclusively in group 5. However, identical patterns of precipitin curves accompany very different sequences in CDR3. Antibodies of group 1, which react only with class II dextrans, differ the most in primary sequence, a finding suggesting that subsites responsible for cross reactivity with class I dextrans may be blocked and that this may be effected by side chains of different amino acids. This finding delineates a new aspect of the relationship of variability in amino acid sequence to antibody complementarity.

Amino Acid Sequence↗
PubMed1952

Preparation and properties of type-specific M antigen isolated from a group A, type 1 hemolytic streptococcus.

Type-specific M antigen was extracted by heating type 1 group A streptococci at pH 2 in a boiling water bath. The protein was then purified by digestion with a preparation of crystalline ribonuclease which was free of proteolytic activity. It was further purified by fractional precipitation with (NH(4))(2)SO(4). Elementary chemical analysis of the preparation thus obtained showed an absence of phosphorus and a sulfur content of 2.46 per cent. In the ultraviolet the maximum absorption was at a wave length of 276 mmicro and the minimum at 255 mmicro. In electrophoresis experiments the preparation showed a single peak in the pH range of 3 to 9, but considerable boundary spreading was observed. The type 1 M antigen was isoelectric at pH 5.3 in sodium acetate buffer of ionic strength 0.1. The serological reactivity of the protein isolated was typical of type 1 M antigen. This protein induced the formation in rabbits of type-specific precipitins and protective antibodies. The absorption of type 1 antibacterial serum with the purified M antigen removed both the protective antibodies and the type-specific precipitins from the serum.

Antibodies↗
PubMed1952

Preparation and properties of a protein (R antigen) occurring in streptococci of group A, type 28 and in certain streptococci of other serological groups.

A group A, type 28 protein antigen, resistant to tryptic digestion and previously considered to be a type-specific substance, was purified and its chemical and immunological properties studied. This protein lacks the characteristic properties of a type-specific M antigen since it is apparently unrelated to virulence and does not induce the formation of protective antibodies although precipitins are readily produced. It is designated the R antigen. The R antigen in addition to occurring in "type 28" group A strains also occurs in some strains of streptococci of other serological groups. Protective antibodies, distinct from precipitins for the R antigen, are present in "type 28" antibacterial sera. The antigens responsible for protection have not been identified, and it is possible that several different types may be included among strains designated as type 28 on the basis of the R antigen. The purified R antigen is phosphorus-free and has a sulphur content of 1.04 per cent. In the ultraviolet a maximum absorption was obtained at a wave length of 280 mmicro and a minimum at 254 mmicro. Electrophoretically the R antigen was found to be 95 per cent homogeneous at most pH values, but at pH 4.6 the main peak separated into two peaks of approximately equal areas, both containing serologically active material. The interpretation of this finding is at present uncertain. The isoelectric pH was at 4.5 in sodium acetate buffer of 0.1 ionic strength. The purified R antigen sedimented in the ultracentrifuge as a single boundary.

Antibodies↗
PubMed1952

Experimental hyperglobulinemia; the effect of injected ribonucleotide on serum globulin levels in rabbits undergoing immunization.

It was shown, by means of salt fractionation procedures and electrophoresis that a marked and sustained hyperglobulinemia regularly resulted when sodium ribonucleate was injected subcutaneously at frequent intervals into rabbits undergoing immunization with horse serum. The hyperglobulinemia was characterized by a large increase in the gamma globulin levels, and a slight increase in the alpha and beta globulin levels. In control experiments done concurrently, the immunization of rabbits with horse serum, accompanied by subcutaneous injections of saline instead of ribonucleate, resulted in only moderate elevations in gamma globulin levels, while injections of ribonucleate alone brought about slight elevations in all three globulin components in some of the animals. Precipitin tests showed that the rabbits immunized with horse serum and simultaneously treated with ribonucleate developed antibody titers against horse serum that were no higher than those of the immunized controls given saline instead of ribonucleate. Indeed, some of the animals treated with horse serum and ribonucleate had globulin levels that were much higher and had antibody titers that were significantly lower than were those of several rabbits receiving horse serum and saline. Injections of ribonucleate alone did not result in the formation of specific antibodies detectable by means of precipitin tests. The results made it plain that the hyperglobulinemia of the animals treated with horse serum and ribonucleate was not due to an excessive production of specific antibodies. The findings as a whole provide further evidence that nucleotides play an important role in the formation of proteins in animals, and they indicate that an abnormally increased utilization of ribonucleotides by cells capable of producing globulins may be a causative factor in the pathogenesis of hyperglobulinemia.

Animals↗
PubMed1978

Microhemagglutination test for detection of antibodies to nuclear Sm and ribonucleoprotein antigens in systemic lupus erythematosus and related diseases.

A reproducible hemagglutination procedure to detect antibodies to Sm and ribonucleoprotein nuclear antigens is described. The application and interpretation is discussed. The hemagglutination test was found to be more sensitive than the immunodiffusion test; however, the hemagglutination test may not detect the presence of low titers of anti-ribonucleoprotein in the presence of a high level of anti-Sm antibody. Anti-ribonucleoprotein antibodies in the presence of high titers of anti-Sm antibodies are best identified by gel precipitation methods where precipitin lines can be characterized by their interaction with precipitin lines produced by known prototype antisera.

Animals↗
PubMed1976

Purification of the polymyxin-released, heat-labile enterotoxin of Escherichia coli.

The heat-labile enterotoxin of Escherichia coli strain H-10407 has been purified by use of a commercially available affinity gel (Affi-Gel 202). This gel possesses a strong and highly specific affinity for the enterotoxin released from intact E. coli cells by polymyxin B. The polymyxin-release technique could be used with fermenter-size batches of E. coli cells grown in a casamino acids-yeast extract medium. With a simple (NH4)2SO4 back-extraction step prior to affinity chromatography, large batches of E. coli enterotoxin could be processed rapidly. Affi-Gel 202-purified E. coli enterotoxin produced a single precipitin band in the presence of several different antisera against crude preparations of the toxin. The same antigen produced a precipitin band in the presence of both cholera antitoxin and antiserum to choleragenoid.

Antigens, Bacterial↗
PubMed1978

Association of infection due to Candida albicans with intravenous hyperalimentation.

Systemic candidiasis is frequently unrecognized before death of the patient because of lack of specific clinical signs, insensitive laboratory tests, and difficulties in culturing Candida albicans from the blood. Recent attention has been focused on the use of serologic testing and ocular signs to increase the rate of diagnosis of candidiasis. Because of the association between hyperalimentation fluids and disseminated candidiasis, a preliminary prospective study was carried out to determine more accurately the incidence in patients receiving hyperalimentation fluids of inapparent candida infection, candida endophthalmitis, or positive candida precipitins. Five of 23 patients developed small, white eye lesions consistent with candida endophthalmitis. Three of the five patients with eye lesions had blood cultures positive for C. albicans, and no patients without eye lesions had positive blood cultures. Candida precipitins were positive in three of the five patients with eye lesions. The results of this study suggest that unrecognized systemic candida infection may be more frequent in patients receiving hyperalimentation than previously suspected.

Adult↗
PubMed1992

Causes of hypersensitivity reactions in flour mill workers in Sudan.

A study of 237 male workers at two flour mills and 71 controls was carried out in Sudan in order to investigate the main possible causes of hypersensitivity reactions to flour dust. Statistical analysis was carried out for the skin test results of wheat, mixed moulds (A13), grain dust, and mixed moulds (group MH) allergen extracts. The results showed that there was no statistical significance between the two exposed groups namely allergy complaining vs. allergy non-complaining except for wheat results in one of the two flour mills which was very slightly significant. But there were highly significant differences between the exposed compared with the control group in all allergens tested. There was no significant correlation, between allergic symptoms and precipitins to wheat or grain dust, nor between precipitins and positive skin tests. The results of respirable flour dust concentrations at different work locations had exceeded the threshold limit values which were taken as 10 mg/m3. Aspergillus supp. and Rhizopus niger were the predominant fungi in the wheat grains and products which were collected from the two mills.

Adult↗
PubMed1980

Isolation and partial characterization of two immunologically similar vitamin D-binding proteins in rat serum.

Two immunologically similar, probably identical, binding proteins for vitamin D and its metabolites (DBP1 and DBP2) were isolated separately from rat serum after approximately 180-fold purification by novel procedures using Blue Sepharose CL-6B chromatography. The freshly purified DBP1 and DBP2 each showed a single band of protein on polyacrylamide gel electrophoresis, and had alpha-mobility, although DBP1 moved slightly faster than DBP2. DBP1 and DBP2 had the same molecular weight, which was estimated as approximately 54,000 by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The isoelectric points of DBP1 and DBP2 were estimated as 4.9 and 5.0, respectively, from the results of isoelectric focusing experiments. DBP1 and DBP2 both appeared to have one binding site for 25-hydroxyvitamin D3 per molecule of protein, with apparently similar association constants at 4 degrees C of 5--7 x 10(9) M-1. The amino acid compositions of DBP1 and DBP2 were also determined and compared. A monospecific antiserum against rat DBP2 was prepared in a rabbit and was used for immunological studies of rat DBP. On double immunodiffusion, anti-DBP2 antiserum produced precipitin lines of complete reaction-of-identity against the purified DBP1, the purified DBP2, and rat whole serum. There was no immunological cross-reactivity between rat DBP and sera from man, dog, and rabbit, but mouse serum showed a pattern of partial identity with rat DBP. When rat serum samples were analyzed by immunoelectrophoresis using anti-DBP antiserum, three patterns of precipitin line were observed: a pattern showing the existence of only DBP1, designated as DBP 1-1; a pattern showing the existence of only DBP2, designated as DBP 2-2; and a pattern showing the existence of both DBP1 and DBP2, designated as DBP 2-1. Using single radial immunodiffusion assay for rat serum DBP, the mean (+/- S.D.) serum DBP concentrations were found to be 461 +/- 59 microgram/ml in adult male rats and 328 +/- 16 microgram/ml in adult female rats, and the difference was significant (p < 0.001). In molar terms, DBPs are present in normal rat serum in large excess relative to vitamin D and its metabolites, and most of the serum DBP, therefore, circulates as apo-DBP, not containing a bound molecule of vitamin D or of its metabolites. The immunoprecipitation studies of DBP in rat serum showed that DBPs were common main transport proteins for naturally occurring vitamin D and its metabolites, and that DBP played some, but not a principal, role in the transport of synthetic 1 alpha-hydroxyvitamin D3.

Amino Acids↗
PubMed1981

Purification of prorennin and production of its antibody.

Prorennin, i.e. the zymogen of rennin, was extracted from fresh calf stomach and purified by ammonium sulfate precipitation, ion exchange chromatography and gel filtration. The purified prorennin was homogeneous as judged by SDS-polyacrylamide gel electrophoresis. A specific antibody to the purified prorennin was induced in rabbits. In a double diffusion test and on immunoelectrophoresis the antibody gave a single precipitin line when run against crude and pure zymogen preparations. In the double diffusion test, the antibody also reacted with a purified rennin but not with gastric proteases (pepsin and pepsinogen) or other proteases (trypsin and Mucor rennin). When the antibody was tested against prorennin and rennin in the double diffusion test, a spur was formed at the junction of the precipitin lines against prorennin and rennin. This result confirms that the two proteins share an antigenically common structure in their molecules and that the activation segment of prorennin contains at least one antigenic determinant.

Animals↗
PubMed1982

Chemical and immunological properties and amino acid sequences of three lysozymes from Peking-duck egg white.

Three lysozymes (DLs-1, -2, and -3) were purified from Peking-duck egg white by adsorption on CM-Sephadex C-25 resin, followed by CM-Sephadex C-25 and Sephadex G-50 column chromatographies. The three enzymes each moved as a single band, but showed different electrophoretic mobilities, on disc-polyacrylamide gel electrophoresis at pH 4.1. Final yields of DL-1, DL-2, DL-3 were 18.2%, 22.0%, and 6.0%, respectively, from the crude material adsorbed on CM-Sephadex resin. The enzymatic activities of DL-1, DL-2, and DL-3 were 1.53, 1.52, and 1.34 times that of hen egg white lysozyme, respectively, using Micrococcus lysodeikticus cell wall as a substrate at pH 6.2 and 37 degrees C. All the DLs lacked histidine and their amino acid compositions differed from each other by a few amino acid exchanges. The amino acid sequences of DL-2 and DL-3 differed from that of DL-1 by two displacements (Ser-37 to Gly and Gly-71 to Arg) and three displacements (Pro-79 to Arg in addition to the same substitutions), respectively. In comparison with Duck II and Duck III lysozymes from Kaki-duck (Hermann and Jollès (1970) Biochim. Biophys. Acta 200, 178-179; Hermann et al. (1971) Eur. J. Biochem. 24, 12-17) as regards amino acid sequences, Duck II is identical to DL-1 except for one displacement of Gln-57 in DL-1 to Glu in Duck II, while Duck III is rather different from our three lysozymes. All DLs gave single precipitin lines with any rabbit antisera against DLs and each precipitin line fused completely with that of any of the DLs in Ouchterlony double diffusion tests. However, the radiobinding inhibition assay showed that some anti-DL antisera clearly discriminated fine differences among the three DLs. The displacement at residue 79 (Pro in equilibrium Arg) gave the clearest immunological difference among the three kinds of displacements found in DLs.

Amino Acid Sequence↗
PubMed1983

Purification and characterization of renin binding protein (RnBP) from porcine kidney.

Renin binding protein (RnBP) was purified from porcine kidney using pepstatin affinity column chromatography, DEAE-Sepharose column chromatography, gel filtration on Ultrogel-AcA 34, aminohexyl-Sepharose 4B column chromatography, and high performance liquid chromatography (HPLC) on TSK-gel G-3000 SW. The purified preparation was homogeneous as judged by sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis, polyacrylamide disc gel electrophoresis and isoelectric focusing on polyacrylamide gel. The isoelectric point was at pH 4.85, and the apparent molecular weight of RnBP was estimated to be 42,000 by SDS-polyacrylamide gel electrophoresis. The preparation did not show any renin activity and was stable for 30 min at 37 degrees C between pH 5.0 and 9.0 or on storage for 4 weeks at 4 degrees C or -80 degrees C. The activity of renin was greatly inhibited by RnBP. From the kinetic analysis of the inhibition we roughly estimated the dissociation constant between renin and RnBP to be about 0.2 nM, assuming that the stoichiometry in the complex, i.e., high molecular weight (HMW) renin, is one to one, and that the complex is inactive. The inhibitory activity of RnBP was lost by acidification at pH 3.0 and the activity of renin was restored. The purified RnBP formed a single precipitin line with the antiserum prepared with the purified HMW renin as antigen, which is RnBP-renin complex (Takahashi, S., et al. (1983) J. Biochem. 93, 265-274), and this line fused with one of the two precipitin lines formed between HMW renin and anti-HMW renin antiserum. The other of the two lines was between renin and anti-HMW renin antiserum. The purified preparation was thus identified as RnBP. The HMW renin was reconstituted with the purified RnBP and renin, and the apparent molecular weight of the reconstituted specimen was estimated to be 60,000 by gel filtration on Ultrogel AcA 44.

Animals↗
PubMed1983

Coagulogens from four living species of horseshoe crabs (Limulidae): comparison of their biochemical and immunochemical properties.

Coagulogens from four kinds of horseshoe crabs (Limulus polyphemus (LP), Tachypleus tridentatus (TT), Tachypleus gigas (TG), and Carcinoscorpius rotundicauda (CR)) were compared in biochemical and immunochemical properties. On SDS-polyacrylamide gel electrophoresis, the reduced coagulogens had a common apparent molecular weight of 20,000, whereas the molecular weights of unreduced samples were 24,000 for the LP protein and 21,000 for the proteins of the three Asian species (TT, TG, and CR). Gel-filtration yielded apparent molecular weights of 19,500 for the LP protein and 15,500 for the other proteins. All coagulogens consisted of 173-175 amino acid residues and their compositions were very similar to one another, e.g., no methionine, and high proportions of basic amino acids, cystine, valine, and phenylalanine. The amino-terminal 14-residue sequence of the LP coagulogen was Gly-Asp-Pro-Asn-Val-Pro-Thr-Cys-Leu-Cys-Glu-Glu-Pro-Thr. Those of the other coagulogens, Ala-Asp-Thr-Asn-Ala-Pro-Ile-Cys-Leu-Cys-Asp-Glu-Pro-Gly, were identical to one another except for the amino-terminal aspartic acid residue of the TG protein and leucine of the CR protein. The carboxyl-terminal residues of the coagulogens were identified as serine (LP), phenylalanine (TT and TG), and tyrosine (CR), respectively. An antiserum to the LP coagulogen produced a single precipitin line against the LP protein but none against the Asian coagulogens. On the other hand, each of the antiserums to TT, TG, and CR coagulogens yielded a precipitin line against the Asian proteins but gave no line against the LP protein.

Amino Acid Sequence↗
PubMed1975

Immunological detection of human bladder carcinoma.

A rabbit antiserum (RABCa) to membrane antigenic extracts of human bladder carcinomas was produced. RABCa failed to detect bladder cancer-specific antigens in gel diffusion reaction against antigenic extracts of bladder carcinoma and normal bladder mucosa. However, RABCa showed higher complement fixation activity against urines from bladder cancer patients compared with normal urines. The micro-complement fixation (CF) assay (108 patients) was positive in 17 of 27 bladder cancer patients (62.9%) compared to only 1 of 29 normals (3.4%). However, 10 of 11 patients with urinary infections also were positive. A micro-Ouchterlony agar gel diffusion assay was also used to study urine samples (118 patients). RABCa produced separate precipitin bands against 20 of 30 bladder cancer urines (66.7%) while only 1 of 24 normal urines gave these bands (4.2%). Again, infected urines were positive (9 of 11). Additionally, urine from patients with benign urological disease was often positive in CF (11 of 41) and Ouchterlony (15 of 43) assays. RABCa serum was absorbed with normal bladder mucosa membrane extracts either once (1X) or three times (3X) to increase the specificity of the Ouchterlong gel diffusion assay. Using RABCa (1X) the per cent of positive bladder cancer urines and normals decreased only slightly, while the number of positive reactions against benign urological disease urines dramatically decreased (17.9%). RABCa (3X) further reduced the per cent of positive reactions with benign urological disease urines (10.3%), greatly reduced the reactivity with infected urines (60.0%), and gave no positive reactions with normal urines, without significantly decreasing the abiltiy to detect bladder carcinoma (51.9%). Although RABCa was 100% effective in detecting high grade (III) bladder tumors, almost two-thirds of all transitional cell papilloma urines were also positive. The nature of the material detected in bladder cancer and infected urines by RABCa is probably a product of in vivo inflammation. It does not appear to be part of the bacterial cell membrane or a bacterial metabolite. CEA (up to 10 ng/ml) did not produce positive precipitin bands with RABCa. Sephadex G-100 fractionation of urines suggests that RABCa reacts in the CF and Ouchterlony assays with a component or urine which has a molecular weight greater than 100,000-200,000 M.W. In summary, an antiserum has been prepared which may be used in micro-complement fixation and micro-Ouchterlony agar gel diffusion assays for immunological screening in the early detection of clinical disease, especially bladder cancer and urinary infection.

Animals↗
PubMedDate not supplied

Detection of polysaccharide cell wall antigen of Neisseria gonorrhoeae in a rabbit model by counterimmunoelectrophoresis.

A rabbit chamber model was developed and inoculated with 10(9) colony-forming units (cfu) of viable Neisseria gonorrhoeae to determine whether the lipopolysaccharide-derived Gc2 polysaccharide cell wall antigens could be detected by counterimmunoelectrophoresis (CIE). Four hours after inoculation, a polymorphonuclear leukocyte response was noted in the chambers; this response was followed by progressive phagocytosis of the organisms and a fall in number of cfu/ml. All visible bacteria were intracellular, and chamber fluids were sterile 6 hr after inoculation. Use of sero specific antisera permitted detection by CIE of the Gc2 polysaccharide antigen in sera of all rabbits within 48 hr after inoculation of the chambers, whereas blood cultures remained sterile throughout the experiment. At 2-6 hr after inoculation, the Gc2 polysaccharide antigen was also detected as a single precipitin band in the chamber fluid of inoculated rabbits. At 24 hr the precipitin band was not observed; rather, a halo above the antigen well was noted. The halo was found to be a nonspecific complex containing the Gc2 polysaccharide antigen and no antibody. In the rabbit model studied, CIE was sufficiently sensitive to detect concentrations of the Gc2 polysaccharide antigen of greater than or equal to 0.97 microgram/ml in serum and chamber fluid.

Animals↗
PubMed1984

Significance of serum antibodies to Histoplasma capsulatum in endemic areas.

To evaluate the specificity of serologic tests for histoplasmosis in an endemic area, we studied sera from 104 consecutive healthy blood donors, testing for antibodies to either histoplasmin or Histoplasma yeast antigen, using complement fixation (CF), radioimmunoassay (RIA), and radial immunodiffusion (ID). Twenty-five subjects (24%) had CF antibody titers of 1:8 or 1:16 to one or both antigens; none had titers above 1:16. Nine subjects (9%) had RIA antibody titers of 1:8 or higher. No titers above 1:8 were found using the yeast antigen; five subjects had titers of greater than 1:16 to histoplasmin using RIA. No precipitin bands were found in any of these subjects. The results of four previous studies in endemic populations yielded similar or lower incidences of positive tests. CF antibody titers to either antigen, RIA antibody titers to yeast antigen of 1:32 or greater, or precipitin bands are rare in persons who live where histoplasmosis is endemic.

Adolescent↗
PubMed2003

Occupational lung disease related to cytophaga endotoxin exposure in a nylon plant.

Workers at a nylon plant developed pulmonary disease with systemic symptoms. Differentiating between humidifier fever and hypersensitivity pneumonitis (HP) is challenging. Cytophaga, an endotoxin-producing bacteria, was isolated from the plant air-conditioning system. A number of workers had systemic and pulmonary symptoms. Precipitins to Cytophaga endotoxin were identified. Several workers underwent lung biopsies demonstrating HP. Inhalation challenges with purified Cytophaga endotoxin were performed on three pairs of subjects: group 1, or employees with clinical features and biopsy consistent with HP; group 2, asymptomatic exposed workers with precipitins; and group 3, nonexposed healthy individuals. All subjects had fever and leukocytosis after inhalation challenge. Acute and/or late pulmonary function changes occurred in groups 1 and 2. Group 3 only had acute and transient pulmonary function changes. Cytophaga bacterial endotoxin is capable of inducing HP as well as humidifier fever.

Alveolitis, Extrinsic Allergic↗