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Biomedical subjects

S Kawabata

Publications and source records attributed to S Kawabata.

At least 127 records · Page 7Linked to original sources
PubMed1996

Tachycitin, a small granular component in horseshoe crab hemocytes, is an antimicrobial protein with chitin-binding activity.

Small granules of horseshoe crab hemocytes contain two known major antimicrobial substances, tachyplesin and big defensin (S5), and at least five protein components (S1 to S6), with unknown functions. In the present study, we examined the biological properties and primary structure of a small granular component S2, named tachycitin. This component was purified from the acid extract of hemocyte debris by two steps of chromatography. The purified tachycitin was a single chain protein with an apparent M(r) = 8,500 on Tricine-SDS-polyacrylamide gel electrophoresis. Ultracentrifugation analysis revealed tachycitin to be present in monomer form in solution. Tachycitin inhibited the growth of both Gram-negative and -positive bacteria, and fungi, with a bacterial agglutinating property. Moreover, tachycitin and big defensin acted synergistically in antimicrobial activities. The amino acid sequence and intrachain disulfide bonds of tachycitin were determined by amino acid and sequence analyses of peptides produced by enzymatic cleavages. The mature tachycitin consisted of 73 amino acid residues containing five disulfide bonds with no N-linked sugar. A cDNA coding for tachycitin was isolated from a hemocyte cDNA library. The open reading frame coded for an NH2-terminal signal sequence followed by the mature peptide and an extension sequence of -Gly-Arg-Lys at the COOH-terminus, which is a putative amidating signal. The COOH-terminal threonine amide released after digestion of tachycitin with lysylendopeptidase was identified. The NH2-terminal 28 residues of tachycitin shows sequence homology to a part of chitin-binding regions found in antifungal chitin-binding peptides, chitin-binding lectins, and chitinases, all of which have been isolated from plants. Tachycitin showed a specific binding to chitin but did not bind with the polysaccharides cellulose, mannan, xylan, and laminarin. Tachycitin may represent a new class of chitin-binding protein family in animals.

Amino Acid Sequence↗
PubMed1996

In vitro/in vivo difference in enhanced skin permeation of nicardipine hydrochloride by the 1-menthol-ethanol system.

The in vitro/in vivo difference in enhanced skin permeation of nicardipine hydrochloride (NC) by simultaneous use of 1-menthol and ethanol (MEW system, 1-menthol:ethanol:water = 5:40:55) was investigated in hairless rats. First, the cutaneous blood flow clearance (clearance from skin to blood flow) of NC per unit area of skin (CLCB/A), which was comparable to the permeability coefficient across skin (PC), was calculated from intracutaneous and intravenous injection data using the deconvolution method; the value was 1.67 microliters/h/cm2. Two formulations containing NC and the MEW system, solution (SOL) and 15% hydroxypropyl cellulose gel (GEL), were used for in vitro and in vivo permeation experiments. The in vitro PC of NC via excised skin from SOL (23.3 microliters/h/cm2) was significantly higher than CLCB/A, and that from GEL (1.48 microliters/h/cm2) was similar to CLCB/A. Consequently, the steady-state concentration of NC in skin during in vivo application of SOL was 6.6 times higher than corresponding in vitro data. In vivo PCs from SOL and GEL were however significantly lower than CLCB/A. These results may be explained by the findings, using a laser Doppler flowmeter, that cutaneous blood flow was decreased by the application of MEW.

Animals↗
PubMed1996

A pylorus-retaining pancreatic head-duodenectomy for cancers of the duodenal papilla and the lower bile duct.

With the development of diagnostic technology, the surgical methods of cancer therapy have been expanded, and operations have been performed using a procedure corresponding to the stage of cancer to improve the postoperative QOL. A 79-year-old man with cancer of the duodenal papilla and obstructive jaundice, and a 63-year-old woman with cholangiocarcinoma in the lower region complicated by cholangitis caused by Candida underwent resections of the pancreatic head and duodenum, and pancreaticogastrostomies retaining the pylorus. Satisfactory results were obtained in both cases. The merits of the procedure were that there were few complaints, sufficient food could be ingested and the QCL was maintained. The benefits of pancreaticogastrostomy are that the anastomosis procedure is simple, the gastric wall is thicker than the jejunum and blood flow is plentiful. The dorsal gastric wall is located close to the pancreatic cut-end, therefore tension is not created, and the pancreatic enzymes are not activated because the anastomosis site does not contact the intestinal fluid. These characteristics should decrease the rate of anastomosis failure which can be a fetal complication. A safer operation is desirable, particularly for elderly patients or patients who have complications.

Aged↗
PubMed1995

Purification, characterization, and cDNA cloning of a 27-kDa lectin (L10) from horseshoe crab hemocytes.

We separated granular components of horseshoe crab hemocytes by a combination of centrifugation on sucrose density gradient and high performance liquid chromatography, and a 27-kDa protein termed L10 was found to be a major component in the large granules (Shigenaga, T., Takayenoki, Y., Kawasaki, S., Seki, N., Muta, T., Toh, Y., Ito, A., and Iwanaga, S. (1993) J. Biochem. (Tokyo) 114, 307-316). In the present work, lectin activity of this protein and its unique primary structure were elucidated. L10 was purified by four steps of chromatography, including dextran sulfate-Sepharose CL-6B, CM-Sepharose CL-6B, Sephacryl S-200, and Mono S. At least three 27-kDa isoproteins, named L10a, L10b, and L10c, were isolated. Their amino acid compositions were almost indistinguishable, and there were no amino sugars. All the isoforms had hemagglutinating activity against human A-type erythrocytes, in a Ca(2+)-independent manner with L10b showing the highest activity. The L10b-mediated hemagglutination was inhibited in the presence of N-acetylglucosamine or N-acetylallolactosamine, and the association constant (Ka) between L10b and N-acetylglucosamine was 1.95 x 10(4) M-1. Furthermore, L10b specifically agglutinated Staphylococcus saprophyticus KD. Ultracentrifugation analysis revealed that L10b is present in monomer form in solution. A cDNA coding for an isoform of L10 was isolated from a hemocyte cDNA library. The open reading frame of the 768-base pair cDNA coded for the signal sequence of 19 residues. The mature protein had 236 residues with the calculated molecular weight of 26,757. Amino acid sequences of the peptides derived from L10c exactly corresponded to the predicted sequence of the cDNA, whereas amino acid replacements of Ile-129 to Val and His-213 to Tyr existed both in L10a and L10b, suggesting that the cDNA codes for L10c. Cysteine was absent and there were five tandem repeats with 47 amino acids in each segment with internal sequence identities of 49-68%. The entire amino acid sequences had no significant sequence similarity with other known proteins.

Agglutination Tests↗
PubMed1995

An abnormal fibrinogen Fukuoka II (Gly-B beta 15-->Cys) characterized by defective fibrin lateral association and mixed disulfide formation.

A dysfibrinogenemia was attributable to a single amino acid substitution from glycine to cysteine at residue 15 of the B beta chain in a fibrinogen molecule designated as fibrinogen Fukuoka II. The fibrinogen Fukuoka II showed prolonged thrombin and reptilase times and impaired fibrinopeptide B release by thrombin, resulting in abolition of fibrin monomer repolymerization under physiological conditions. Repolymerization of the des-(B beta 1-42)-fibrin monomers, however, was not distinguished from the normal pattern of des-(B beta 1-42)-fibrin monomers, suggesting that no other abnormality existed in fibrinogen Fukuoka II. Although an additional cysteine was substituted at residue 15 of the B beta chain, fibrinogen Fukuoka II had no free sulfhydryl group within the molecule. Instead, fibrinogen Fukuoka II formed a disulfide bond with cysteine, albumin, another mutated B beta chain within the same molecule, or intermolecular dimeric fibrinogen Fukuoka II. The mutation in fibrinogen Fukuoka II was the same as that in fibrinogen Ise published previously (Yoshida, N., Wada, H., Morita, K., Hirata, H., Matsuda, M., Yamazumi, K., Asakura, S., and Shirakawa, S. (1991) Blood 77, 1958-1963). Fibrinogen Ise, however, has been described as having prolonged thrombin time but normal reptilase time. Reasons for the discrepancy were not clear. Analysis of the B beta 1-42 fragment showed that fibrinogen was heterogeneous at position 31 of the B beta chain with respect to proline or hydroxyproline.

Amino Acid Sequence↗
PubMed1995

Overexpressed tau protein in cultured cells is phosphorylated without formation of PHF: implication of phosphoprotein phosphatase involvement.

Pyramidal neurons in affected regions of Alzheimer's disease (AD) brain contain neurofibrillary tangles (NFT), aggregates of paired helical filaments (PHF) composed mainly of phosphorylated microtubule-associated protein tau. To explore the role of tau phosphorylation in the aggregation of tau into PHF, we constructed mammalian cell culture systems producing high levels of intracellular phosphorylated tau. COS-1 fibroblast-like cells were transiently transfected to simultaneously express tau, MAP kinase (MAPK), and MAP kinase kinase (MAPKK), or alternatively to express tau and glycogen synthase kinase 3 (GSK3). B103 neuron-like cells (which contain MAPK but little tau or GSK3) were stably transfected to express tau or tau and GSK3. In both systems, GSK3-transfected cells contained tau AT8/M (defined by AT8 staining and tau PHF-like mobility), but MAPK-transfected cells required phosphatase inhibitors, such as okadaic acid (OKA) or calyculin (CAL), to produce tau AT8/M. In vitro, the same concentrations of CAL and OKA inhibit phosphatases 1 and 2A (PP1 and PP2A), except that 100-1000 times as much OKA is needed to inhibit PP1. Inducing tau phosphorylation at the AT8 site in MAPK-transfected cells required 2-10 times more OKA than CAL, suggesting both PP1 and PP2A helped block the phosphorylation. Though levels of tau AT8/M reached 2-8% of total cellular proteins in COS-1 cells, the ratio of particulate to supernatant tau levels did not increase, and no tangles were observed; perhaps post-translational modifications or co-aggregating proteins are needed to induce PHF.

Animals↗
PubMed1995

Nucleotide sequence of the cDNA encoding the proenzyme of phenol oxidase A1 of Drosophila melanogaster.

Clones encoding pro-phenol oxidase [pro-PO; zymogen of phenol oxidase (monophenol, L-dopa:oxygen oxidoreductase, EC 1.14.18.1)] A1 were isolated from a lambda gt10 library that originated from Drosophila melanogaster strain Oregon-R male adults. The 2294 bp of the cDNA included a 13-bp 5'-noncoding region, a 2070-bp encoding open reading frame of 690 amino acids, and a 211-bp 3'-noncoding region. A hydrophobic NH2-terminal sequence for a signal peptide is absent in the protein. Furthermore, there are six potential N-glycosylation sites in the sequence, but no amino sugar was detected in the purified protein by amino acid analysis, indicating the lack of an N-linked sugar chain. The potential copper-binding sites, amino acids 200-248 and 359-414, are highly homologous to the corresponding sites of hemocyanin of the tarantula Eurypelma californicum, the horseshoe crab Limulus polyphemus, and the spiny lobster Panulirus interruptus. On the basis of the phylogenetic tree constructed by the neighbor-joining method, vertebrate tyrosinases and molluscan hemocyanins constitute one family, whereas pro-POs and arthropod hemocyanins group with another family. It seems, therefore, likely that pro-PO originates from a common ancestor with arthropod hemocyanins, independently to the vertebrate and microbial tyrosinases.

Amino Acid Sequence↗
PubMed1995

A novel type of limulus lectin-L6. Purification, primary structure, and antibacterial activity.

Lipopolysaccharide (LPS)-binding protein(s) was first screened in the detergent extract of horseshoe crab (limulus) hemocytes using LPS-immobilized agarose. A protein, designated L6 (M(r) = 27,000), was found to bind to LPS-agarose and was eluted with EDTA or o-phenanthroline. The L6 protein, however, did not inhibit the LPS-mediated activation of a limulus serine protease zymogen factor C. L6 had an affinity to the matrix of Sepharose CL-6B itself, and it could be eluted with high concentrations of monosaccharides (0.5-1.0 M), such as glucose, mannose, and galactose, suggesting a lectin-like nature. The entire amino acid sequence of L6 was determined by sequencing peptides derived from CNBr and enzymatic cleavages. L6 contained 7 half-cystines, and 1 cysteine residue at position 201 had a free SH-group. In addition, positions of the remaining three intrachain disulfide bonds were assigned by amino acid and sequence analyses of three cystinyl peptides produced by lysyl endopeptidase digestion. These results indicated that the entire sequence of L6 consisted of 221 residues with no N-linked sugar and was composed of six tandem repeats, each consisting of 33-38 amino acid residues. Inductively coupled plasma spectrometry of L6 indicated the presence of 0.75 mol zinc/mol of protein. No significant sequence homology was observed between L6 and other proteins, including various animal lectins and LPS-binding proteins. However, L6 showed agglutinating activity on LPS-coated sheep erythrocytes and Gram-negative and Gram-positive bacteria, it inhibited the growth of Gram-negative bacteria, and thus it presumably recognizes carbohydrate components in the cell wall of bacteria.

Amino Acid Sequence↗
PubMed1995

Inhibition of gastrin-stimulated enterochromaffin-like cell proliferation and mucosal histamine production in the rat stomach by the somatostatin analogue octreotide.

The effect of octreotide, a potent and long-acting analogue of somatostatin, on gastrin-stimulated proliferation and function of enterochromaffin-like (ECL) cells were examined in rats. Animals were divided into four groups and each group was continuously infused with saline, octreotide alone (40 micrograms/kg per day), gastrin alone (60 nmol/kg per day), or octreotide (40 micrograms/kg per day) plus gastrin (60 nmol/kg per day) respectively for 9 days via osmotic minipumps. Gastrin induced the increase of the bromodeoxyuridine labeling index and density of oxyntic mucosal ECL cells as well as oxyntic mucosal histidine decarboxylase activity. Octreotide completely abolished the gastrin-induced increases in the labeling index and density of ECL cells and oxyntic mucosal histidine decarboxylase activity. These results indicate that octreotide inhibits gastrin-stimulated proliferation of ECL cells and histamine production by these cells.

Animals↗
PubMed1995

cDNA cloning and deduced amino acid sequence of prothrombin activator (ecarin) from Kenyan Echis carinatus venom.

The complete amino acid sequence of ecarin is deduced from the nucleotide sequence of a cDNA clone isolated by screening a venomous gland cDNA library of Kenyan Echis carinatus. The cDNA sequence with 2379 base pairs encodes an open reading frame of 616 amino acids with a remarkable sequence homology to the putative precursor protein of trigramin from Trimeresurus gramineus venom (61% identity) and a large hemorrhagin, jararhagin, from the pit viper Bothrops jararaca venom (62% identity). Thus, ecarin, as well as jararhagin and trigramin, is translated as a precursor protein, which may be processed posttranslationally. The ecarin proprotein has a "cysteine switch" motif (-Pro-Lys-Met-Cys-Gly-Val-) similar to that involved in the activation of matrix metalloproteinase zymogens. The processed mature protein consists of 426 amino acid residues (residues 191-616), showing the strongest sequence similarity with that of Russell's viper venom factor X activator (RVV-X) heavy chain (64% identity). Like RVV-X heavy chain, ecarin contains metalloproteinase, disintegrin, and cysteine-rich domains. The metalloproteinase domain has a typical zinc-chelating sequence (-His-Glu-Xaa-Xaa-His-Xaa-Xaa-Gly-Xaa-Xaa-His-), as found in crayfish astacin. In the disintegrin domain of ecarin, the Arg-Gly-Asp sequence is replaced by Arg-Asp-Asp, as found in the disintegrin domains of RVV-X heavy chain (Arg-Asp-Glu) and a guinea pig sperm fusion protein, PH-30 beta (Thr-Asp-Glu). These findings show that while there are structural and evolutionary relationships among these proteins, each has a unique functional activity.

Amino Acid Sequence↗
PubMed1995

A limulus intracellular coagulation inhibitor type 2. Purification, characterization, cDNA cloning, and tissue localization.

We described in a foregoing report findings on serpin, a serine protease inhibitor, newly identified in horseshoe crab (Tachypleus tridentatus) hemocytes and we name it limulus intracellular coagulation inhibitor, LICI (Miura, Y., Kawabata, S., and Iwanaga, S. (1994) J. Biol. Chem. 269, 542-547). This serpin specifically inhibits limulus lipopolysaccharide-sensitive serine protease, factor C. In ongoing studies on limulus serpin, we have found another inhibitor, LICI type-2 (LICI-2), which inhibits not only factor C (k1 = 7.1 x 10(4) M-1 S-1) but also limulus clotting enzyme (k1 = 4.3 x 10(5) M-1 S-1). LICI-2 inhibits mammalian serine proteases, including alpha-thrombin, salivary kallikrein, plasmin, and tissue plasminogen activator. The inactivation of plasmin is the most rapid (k1 = 1.2 x 10(6) M-1 S-1). The purified LICI-2 is a single chain glycoprotein with an apparent M(r) = 42,000. A cDNA for LICI-2 was isolated and the open reading frame coded for a mature protein of 386 amino acids, of which 160 residues were confirmed by peptide sequencing. Although LICI-2 shows significant sequence similarity to the previous limulus serpin, LICI-1 (42% identity), LICI-2 contains a unique putative reactive site, -Lys-Ser-, distinct from that of LICI-1 (-Arg-Ser-). Northern blotting revealed expression of LICI-2 mRNA only in hemocytes, and not in heart, brain, stomach, intestine, coxal gland, and skeletal muscle. The immunoblot of large and small granule components with antiserum against purified LICI-2 suggests that LICI-2 is stored specifically in large granules, as in the case of LICI-1, and is released in response to external stimuli. We propose that the LICIs be classified into a new subfamily of intracellular serpins, regulated secretory serpins.

Amino Acid Sequence↗
PubMed1995

Cholecystokinin is not a physiological regulator of gastric pepsin secretion in rats.

The physiological relevance of cholecystokinin (CCK) in gastric pepsin secretion is unclear, although CCK has been reported to stimulate pepsin secretion in intact animals and in dispersed chief cell. To clarify the physiological role played by this peptide in pepsin secretion, we determined the effects of intravenous infusions of CCK on gastric pepsin release, and investigated the effect of endogenous CCK released by small amounts of trypsin inhibitor on pepsin secretion in conscious rats. The infusion of CCK-8 at 1 nmol/kg per h resulted in a plasma CCK concentration of 204 pM and a 2.5-fold increase in pepsin secretion compared to the baseline rate. The infusion of CCK-8 at 0.3 nmol/kg per h resulted in a plasma CCK concentration of 41.8 pM and also caused a significant increase in pepsin secretion compared to the baseline rate. However, the infusion of CCK-8 at 0.1 nmol/kg per h (plasma CCK level, 19.9 pM), which is still far beyond the physiological plasma levels of CCK, did not significantly affect pepsin secretion. In addition, the intraduodenal infusion of soybean trypsin inhibitor increased the plasma CCK concentration to 4.4 pM, a value comparable to that observed after feeding (3.3 pM), but again, this had no effect on gastric pepsin secretion. We conclude that CCK is not a physiological regulator of gastric pepsin secretion in rats.

Animals↗
PubMed1995

A novel big defensin identified in horseshoe crab hemocytes: isolation, amino acid sequence, and antibacterial activity.

Hemocytes of the horseshoe crab (limulus) contain a family of arthropodous peptide antibiotics, termed the tachyplesin family, and antibacterial protein, called anti-LPS factor, of which the former is located in the small (S) granules and the latter in the large (L) granules of the hemocytes. In our ongoing studies on granular components, we have identified here a novel defensin-like substance present in both L- and S-granules. This substance strongly inhibits the growth of Gram-negative and -positive bacteria, and fungi, such as Candida albicans. The isolated substance, tentatively termed "big defensin," consists of 79 amino acid residues, of which the COOH-terminal 37 residues have a sequence similar to those of mammalian neutrophil-derived defensins, especially rat defensin. Characterization of the disulfide motif in big defensin indicated that the disulfide array is identical to that of beta-defensins from bovine neutrophils. One clear structural difference is that the limulus hemocyte-derived big defensin has an extension of the NH2-terminal hydrophobic sequence with 35 amino acid residues followed by the COOH-terminal cationic defensin portion. This amphipathic nature of big defensin seems likely to be associated with its potent antibacterial activity. Furthermore, antibacterial activities of the NH2-terminal hydrophobic region and the COOH-terminal defensin portion separated by tryptic digestion are significantly different: the former displays a more potent activity against Gram-positive bacteria, whereas the latter is more potent against Gram-negative bacteria. Big defensin, therefore, may prove to represent a new class of defensin family possessing two functional domains with different antimicrobial activities.

Amino Acid Sequence↗
PubMed1995

Substrate specificity of rabbit liver metalloendopeptidase and its new fluorogenic peptide substrates.

A metalloendopeptidase (MEP) isolated from rabbit liver microsomes with substrate specificity for peptides containing Arg at the P1 and P4 positions has recently proved to be identical to soluble angiotensin-binding protein present in the cytosol. Here we describe the peptide-degrading specificity of MEP, determined using various bioactive peptides and novel fluorogenic substrates for the enzyme. MEP degraded oligopeptides, including bradykinin, alpha-neoendorphin, bovine adrenal medulla dodecapeptide, substance P, bombesin, neurotensin, and alpha-endorphin, but not polypeptides such as reduced lysozyme and histone H4, hence, MEP probably belongs to the family of endo-oligopeptidases. It cleaved most preferentially at the -Phe-Ser- bond of bradykinin (kcat/Km = 2.8 x 10(4) M-1.S-1) but did not cleave high molecular weight and low molecular weight kininogens, the precursors of bradykinin. MEP did not cleave angiotensin I, dynorphin A 1-13, somatostatin, and luteinizing hormone-releasing hormone, some of which are good substrates for metalloendopeptidase-24.15, metalloendopeptidase-24.16, N-arginine dibasic convertase, and yeast endopeptidase-24.15 related peptidase. An active site-directed inhibitor of metalloendopeptidase-24.15, N-[1-(R,S)-carboxyl-3-phenylpropyl]-Ala-Ala-Phe-p-aminobenzoate also had no effects on the amidolytic activity of MEP. Based on the cleavage sites of bioactive peptides and processing sites of vitamin K-dependent proproteins, intramolecularly quenched fluorogenic peptide substrates were newly synthesized. Among the thirteen substrates used, the most reactive was 2-aminobenzoyl-Ala-Arg-Val-Arg-Arg-Ala- Asn-Ser-2,4-dinitroanilinoethylamide (kcat/Km = 9.3 x 10(5) M-1.S-1). An angiotensin antagonist, [Sar1, Ala8]-angiotensin II, inhibited hydrolysis of the substrate by MEP in a competitive manner (Kl = 7.6 microM). MEP cleaved oligopeptides even on the carboxyl side of proline residue and these peptides are resistant to hydrolysis by the cytosol-derived proteasome, therefore MEP may participate in the catabolism of oligopeptides in the cytosol, together with other endo-oligopeptidases.

Amino Acid Sequence↗
PubMed1995

Activity of eight fluoroquinolones against both methicillin-susceptible and -resistant Staphylococcus aureus isolated from skin infections.

The in vitro susceptibility of Staphylococcus aureus to eight fluoroquinolones, norfloxacin, ofloxacin, enoxacin, ciprofloxacin, lomefloxacin, tosufloxacin, sparfloxacin, and nadifloxacin was established by agar dilution tests, 71 isolates of methicillin-susceptible (MSSA) and 74 isolates of -resistant S. aureus (MRSA) isolated from skin infections. Among all of the fluoroquinolones, nadifloxacin exhibited the lowest MIC for both MSSA and MRSA. In addition, there were no resistant S. aureus, neither MSSA and MRSA, to nadifloxacin. With the exception of nadifloxacin, the incidence of MRSA resistant to fluoroquinolones has gradually increased in recent years. Over half of the MRSA strains were resistant to norfloxacin, ofloxacin, enoxacin, ciprofloxacin, and lomefloxacin.

Anti-Infective Agents↗
PubMed1995

[Spontaneous cure of pneumonia caused by Chlamydia pneumoniae].

A 62-year-old male was admitted to our hospital after an abnormal shadow was pointed out by Chest X-ray in June, 1994, even though he was asymptomatic otherwise (first episode). The serum IgG antibody against Chlamydia pneumoniae was elevated up to 512-fold in the acute phase and decreased to 32-fold in the convalescent phase using the micro-immunofluorescence (MIF) test, indicating a C. pneumoniae acute infection. In fact, no other micro-organisms were detected. The patient recovered from the pneumonia without any treatment. He was admitted to our hospital again after having right chest pain in December, 1994 (second episode). An X-ray examination revealed a slight infiltration of the right lower lung field and pleural effusion. In this episode, he received therapy with carbapenem anti-bacterial agent and he recovered from the pneumonia 9 days after the administration of the antibiotic. The serum IgG titer against C. pneumoniae was elevated up to 1024-fold on admission, indicating mixed infection with bacteria and C. pneumoniae. It was concluded that both of these episodes indicated a spontaneous cure of the pneumonia which had developed from C. pneumoniae.

Antibodies, Bacterial↗