Serum cytokine levels in atopic dermatitis

Elevated IgE responses and eosinophilia observed in patients with atopic dermatitis (AD) may reflect increased responses of type 2 T-helper (Th2) cytokines with a concomitant decrease in interferon-gamma (IFN-gamma) production. However, the cross-regulation of Th1/Th2 derivation and function in AD patients are incompletely characterized. Therefore, we investigated serum levels of several cytokines [interleukin (IL)-18, IL-12, IL-10, IL-2 and IFN-gamma] in patients with AD to assess their possible relationships to the severity of disease. Serum IL-18 levels in AD patients were significantly higher than those in healthy controls [207 pg/mL; 95% confidence interval (CI), 172-242 pg/mL vs. 144 pg/mL; 95% CI, 116-178 pg/mL; P = 0.026]. Those IL-18 levels significantly correlated with eosinophil counts and serum soluble IL-2 receptor (sIL-2R) levels, and showed a tendency to correlate with clinical severity scores and serum IgE levels. IL-2 levels showed a significantly inverse correlation with serum IgE levels, and IL-12 levels clearly correlated with IL-10 levels. These results suggest the value of serum IL-18 levels as a parameter of AD activity and may support a possible role for IL-18 in the pathogenesis of AD. The inverse correlation between IgE levels and IL-2 levels suggests that IgE production may be inhibited by IL-2 in patients with AD. Furthermore, the correlation of IL-12 levels with IL-10 levels may support the previous reports that show the induction of IL-10 production by human natural killer cells and/or T cells stimulated with IL-12 in vitro.

IL-12 and IL-18 synergistically induce the bactericidal activity of murine peritoneal cells against M. leprae

We examined the effect of IL-12 and IL-18 on bactericidal activities of mouse peritoneal cell (PC) against Mycobacterium leprae (M. leprae). We demonstrated that IL-12 and IL-18 synergistically induced the NO-dependent bactericidal activity of PC by stimulating Natural Killer (NK) cells and T-cells through IFN-gamma production. IL-12 and IL-18 induced host cell death through NK-cells and T-cells. Therefore. IL-12 and IL-18 play an important role on direct killing of intracellular M. leprae and on indirect killing of them through inducing host cell death.

Protective responses against experimental Mycobacterium leprae infection in mice induced by recombinant Bacillus Calmette-Guérin over-producing three putative protective antigen candidates

The components of Ag85 (Ag85A, Ag85B, and Ag85C) are putative protective antigen candidates against mycobacterial infection. A recombinant Mycobacterium bovis Bacillus Calmette-Guérin (rBCG) over-producing Ag85A, Ag85B, and MPB51 (rBCG/BA51) was constructed. rBCG/BA51 could secrete these antigens at levels more than five times higher than parental BCG. Immunization of C57BL/6 and BALB/c mice with this rBCG reduced the multiplication of Mycobacterium leprae in the foot pads of both strains of mice. The inhibition by rBCG/BA51 was more evident than that by parental BCG.

Inhibition of multiplication of Mycobacterium leprae in mouse foot pads by recombinant Bacillus Catmette-Guérin (BCG)

Immunization of mice with recombinant Mycobacterium bovis Bacillus Calmette-Guérin (rBCG) which over-produces a putative protective antigen candidate, the A component of antigen 85 complex (Ag85A), reduced the multiplication of Mycobacterium leprae in the foot pads of mice. The inhibition by this rBCG (rBCG/85A) was more evident than that with parental BCG. Repeated rBCG/85A immunization significantly could reduce M. leplae multiplication in mice. This is first report of rBCG to control mycobacterial infection in animal model. Therefore, rBCG technique may be useful for the development of a more effective mycobacteria vaccine.

The antigen 85 complex vaccine against experimental Mycobacterium leprae infection in mice

The proteins in culture filtrate derived from Bacillus Calmette-Guérin (BCG) were examined for protection against infection by Mycobacterium leprae. Immunization with the major secreted proteins, antigen 85 complex (Ag 85) A, B and C, induced effective protective immunity against multiplication of M. leprae in the foot pads of mice. The most effective protection was observed when mice were immunized with Ag 85A. A single immunization with Ag 85 could induce antigen-specific interferon gamma (IFNgamma) synthesis and more effective protection than live BCG vaccine. This study demonstrates that Ag 85 is an important immunoprotective molecule against leprosy infection.

Leprosy in hypertensive nude rats (SHR/NCrj-rnu)

Since more than a decade ago, we have attempted to develop spontaneously hypertensive rats carrying the nude gene that permits high multiplication of Mycobacterium leprae. A congenic strain carrying nude (rnu) and hypertensive genes was produced using SHR/NCrj females and F344/NJcl-rnu males. Cross-intercross was carried out 12 times to establish the hypertensive nude rat congenic strain. As a result of the genetic monitoring test with NE12F2 generation rats, the genetic profile of the SHR/NCrj-rnu rats was the same as that of the SHR/NCrj rats except for the rnu gene. We have successfully developed a hypertensive congenic nude rat strain (SHR.F344Hfh11; SHR/NCrj-rnu). An increase in the blood pressure in nude rats was found to begin at a slightly delayed age when compared with their hairy litter mates. Both female and male rats showed the highest blood pressure at approximately 20 weeks of age--166 +/- 1.4 and 197 +/- 11 mm Hg in nude rats and 175 +/- 11 and 193 +/- 3.2 mm Hg in their hairy litter mates in female and male rats, respectively. In the present study, comparisons were made on the susceptibility to M. leprae in hypertensive SHR/NCrj-rnu and normotensive F344/NJcl-rnu rats. We have reconfirmed that hypertensive SHR/NCrj-rnu rats of the NE12F3 generation were highly susceptible to M. leprae. In the SHR/NCrj-rnu rats of both sexes excellent massive swelling due to multiplication of M. leprae was observed and, also, nodular lesions were produced in uninoculated fore feet and lips while those sites in the F344/NJcl-rnu rats showed only a slight swelling of the inoculated feet with mild nodular lesions. Although mild lymphocyte proliferation was seen only in the M. leprae-inoculated site with numerous bacilli and partial necrosis in the SHR/NCrj-rnu rats, at noninoculated sites, multiplication of M. leprae was only observed in the cells of the mononuclear phagocyte system. However, in F344/NJcl-rnu rats, lymphocyte proliferation with a few neutrophils was seen at the site of inoculated hind foot pads and everywhere at the site of multiplication of M. leprae. There was a wide difference in the susceptibility to M. leprae between the SHR/NCrj-rnu and the F344/NJcl-rnu rats.

[Bacteria killing by macrophages via NF-IL6 gene dependent mechanism: the susceptibility to Mycobacterium leprae in NF-IL6 knockout mice]

Transcription factor, NF-IL6 recognizes the same nucleotide sequences as C/EBP, and it is predominantly expressed in macrophages. Tanaka et al. reported that NF-IL6 knockout mice are highly susceptible to Listeria monocytogenes and Salmonella typhimurium due to impairment of bacteria killing by activated macrophages. We have tried to see the susceptibility for Mycobacterium leprae infection with intraperitoneal(i.p.) or both hind foot pad (BHF) in the NF-IL6 knockout mice with wild control mice. Although we examined the cytokine genes expression and induction of such as IL-1 alpha, IL-6, IL-12, IL-18/IGIF, NO2. and TNF alpha in the peritoneal macrophages on 1 month after inoculation, also IL-2 and IL-10 by splenocytes on 1 and 8 months after infection. Following the inoculation of M. leprae with i.p. or BHF, the mice were sacrificed from 1 to 12 months after inoculation in order to confirm the multiplication and the dissemination of the infection. Many leprosy bacilli was found in the peritoneal macrophages of NF-IL6 knockout mice on 1 month after inoculation while that of the wild control mice was showing disappear. In the case of the intraperitoneal infection, NF-IL6 knockout mice shows predominantly multiplication of M. leprae on the abdemino-organs such as omentum and also scrotum with male. Although NF-IL6 knockout mice with BHF inoculation did not show any swelling at the site of inoculated foot, however the foot pad on 12 month after inoculation was processed for Fite-Faraco's stain and microscopy shows many leprosy bacilli in the intermuscular layer or around the blood vessels/sciatic nerve in the subcutaneous tissue and then the multiplication extended to the toes. Besides the induction of cytokines such as IL-1 alpha, TNF alpha and IL-12 production were observed stronger in culture supernatant of peritoneal macrophages of NF-IL6 knockout mice than that of the wild control mice. IL-2 production was also observed strong in culture supernatant in splenocytes of NF-IL6 knockout mice while that of IL-10 production never induced at anytime. This is doubtless the results of impairment of bacteria killing by macrophages via NF-IL6 gene dependent mechanism not to antigen specific immune system.

Susceptibility to Mycobacterium leprae of ALY (alymphoplasia) mice and IFN-gamma induction in the culture supernatant of spleen cells

The aly/aly (alymphoplasia) mice from a mutation of a colony of the C57BL/6J mouse strain, which has a systemic absence of lymph nodes and Peyer's patches, are deficient in both T- and B-cell-mediated immune functions. We have undertaken a comparison of susceptibility to Mycobacterium leprae of ALY (aly/aly, aly/+) mice with C57BL/6J mice. The aly/aly mouse was found to have an excellent high susceptibility to M. leprae with no distinction between female and male. The aly/+ mouse also was more susceptible to M. leprae at an earlier stage than the C57BL/6J mouse. Therefore, we examined and compared the cytokine gene expression and gamma interferon (IFN-gamma) induction in the splenocytes of ALY mice. The expression of interleukin 4 (IL-4), IL-10 and IL-12 mRNA was weakly stimulated with ML-lysate in inoculated aly/aly mice but IL-2, IL-6, IGIF/IL-18 and IFN-gamma mRNA were not observed. None of the cytokine genes used appeared, except the mRNA for IL-1-alpha, when uninfected cultured spleen cells were stimulated with ML-lysate. Also, IFN-gamma production was not induced. However, the appearance of these cytokine genes was observed when stimulated with concanavalin A (ConA), and IFN-gamma production was also induced in the culture supernatant by aly/+ and even aly/aly mice stimulated with ConA. To examine the reason why IFN-gamma cannot be produced by splenocytes of ALY mice inoculated with M. leprae, we detected cytokine gene expression and IFN-gamma induction in the presence of recombinant murine IL-12 or IGIF/IL-18. IL-2 mRNA expression was detected in all of the mice tested in the presence of IL-12 but not in aly/aly mice under IGIF/IL-18, and iNOS mRNA expression was not observed in aly/aly mice under IL-12 or IGIF/IL-18. IL-4 and IL-10 mRNA were detected by aly/aly mice only by exposure to IGIF/IL-18. In culture, the supernatant with ML antigens of the aly/aly mice did not produce IFN-gamma in spite of the presence of IL-12 and IGIF/IL-18, while IFN-gamma was weakly induced in aly/+ mice stimulated with ML-lysate and in the presence of IGIF/IL-18. Nevertheless, IFN-gamma production was observed in splenocytes of the aly/aly mice stimulated with ConA and also with IGIF/IL-18 plus anti-CD3 antibody. Our results suggest that ALY mice might be showing a high susceptibility to M. leprae because of deficient priming for activation of T cells with the leprosy bacilli infection. Moreover, it is possible that the phagocytic activities of the macrophages of ALY mice are also impaired.

Inhibition of multiplication of Mycobacterium leprae in mouse foot pads by immunization with ribosomal fraction and culture filtrate from Mycobacterium bovis BCG

Immunization of mice with the ribosomal fraction from ruptured Mycobacterium bovis Bacillus Calmette-Guérin (BCG) and the culture filtrate reduced remarkably the multiplication of Mycobacterium leprae in the foot pads of mice. This is the first reported case of the protective activity against M. leprae multiplication in mice of the BCG ribosomal fraction and culture filtrate. The inhibition was more evident with the culture filtrate than with the ribosomal fraction. When the ribosomal proteins separated from ribosomal RNA were injected into mice, only slight inhibition was observed. Ribosomal RNA alone did not inhibit at all, in contrast to the conclusion reported by Youmans and Youmans.

Cytokine gene expression in the foot pad and spleen of BALB/cAJcl mice infected with M. leprae

The cytokine mRNAs expressed in the foot pads and spleens of BALB/cAJcl mice infected with Mycobacterium leprae were studied by the reverse transcriptase-polymerase chain reaction (RT-PCR) method using cytokine-specific primers for interleukin-1 alpha (IL-1 alpha), -2, -4, -6, -10, -12-(p40), gamma interferon (IFN-gamma), tumor necrosis factor-alpha (TNF-alpha), and TNF-beta, and then for CD4 and CD8 markers. The pattern of cytokine gene expression in the foot pad which supports M. leprae growth was different from the expression in the spleen which does not permit M. leprae multiplication in mice. Before BALB/cAjcl mice were infected with M. leprae, IL-1 alpha and TNF-beta mRNAs were expressed physiologically in the foot pad while all of the cytokine genes examined were expressed in the spleen. In the foot pads of mice inoculated with M. leprae, in addition to the physiological appearance of IL-1 alpha and TNF-beta mRNAs, these signals were intensified. TNF-alpha expression was induced by the infection. On the other hand, in the spleens of mice inoculated with M. leprae, CD4 mRNA expression disappeared on day 1 of the infection, which was accompanied by the reduced expression of IL-2, -4, -6, and -12 mRNAs. The recovery of CD4 mRNA expression at a latter stage was accompanied by a corresponding increase of the cytokine mRNA expression. It was suspected that these results might permit restricted growth of M. leprae in the foot pads of normal mice. Furthermore, our study suggests that tissue-specific, local, immunologic characteristics are important in M. leprae growth.

Suppression of adjuvant arthritis in rats by induction of oral tolerance to mycobacterial 65-kDa heat shock protein

Oral administration of mycobacterial 65-kDa heat shock protein (HSP) given daily for 5 days prior to immunization with Mycobacterium tuberculosis (Mt) suppressed the development of adjuvant arthritis (AA) in rats. AA was significantly suppressed by 30 and 300 micrograms HSP, and variably by 0.3, 3 micrograms or 1 mg. Histological analysis of joint samples obtained from control and test rats confirmed the suppression of AA in the fed group. Feeding Mt or hen egg lysozyme (HEL) failed to affect AA, indicating that the suppression was HSP specific. The oral administration of 30 micrograms HSP decreased both delayed-type hypersensitivity (DTH) reactions and proliferative responses to HSP and Mt. In addition, the proliferation of lymph node cells (LNC) from Mt-sensitized rats was inhibited by the addition of spleen cells (SPC) from HSP-fed animals, possibly by the secretion of transforming growth factor (TGF)-beta. Spleen cells obtained from tolerized donors were capable of transferring the tolerance to naive recipients. These results demonstrate that feeding HSP is an effective way to suppress AA and that the suppression of AA may be mediated by regulatory T cells generated following oral administration of mycobacterial 65-kDa HSP.

Detection of autoantibodies to the pancreatic islet heat shock protein 60 in insulin-dependent diabetes mellitus

Autoantibodies against heat shock protein (hsp) 60 have been reported to be detected in sera of non-obese diabetic mice, in an experimental model of IDDM. However, there are only a few studies which have examined IDDM patients for antibodies against mammalian hsp60. We produced murine hsp60 derived from pancreatic beta cells which has high homology to human hsp60 and examined antibodies against the hsp60 in IDDM patients using an enzyme-linked immunosorbent assay. We extended the analysis to patients with other immune-mediated diseases and non-insulin-dependent diabetes mellitus (NIDDM). Positive sera for hsp60 antibody were more frequently detected in 13 out of 84 IDDM (15.5%) and 5 out of 25 rheumatoid arthritis patients (20%), when compared to healthy subjects (1/85; 1.2%, P < 0.001 and P < 0.01, respectively). The levels of hsp60 antibodies of IDDM (0.218 +/- 0.227) and rheumatoid arthritis patients (0.259 +/- 0.191) were significantly higher than those of healthy subjects (0.076 +/- 0.131, P < 0.001, P < 0.01, respectively). Patients with slowly progressive IDDM (n = 26), autoimmune thyroid disease (n = 42), or NIDDM (n = 40) had levels of hsp60 antibodies similar to those in healthy subjects. We found no relationship between the levels of hsp60 antibodies and islet cell antibodies (ICA) or antibodies to glutamic acid decarboxylase (GAD65) in IDDM patients. In conclusion, hsp60 antibodies were detected in Japanese IDDM as well as in rheumatoid arthritis patients. Although the positivity was low, the detection of hsp60 antibodies may be helpful for diagnosis of IDDM especially in GAD65 Ab- or JCA-negative Japanese patients.

[BCG vaccination to Mycobacterium leprae infection in mice]

BCG vaccine (Tokyo strain) was given in BALB/cA mice intradermally 1 or 3 months before Mycobacterium leprae (M. leprae) challenge as modified Shepard's method. The vaccine dosage was 10(7-8) or 10(6). The BCG gave good protection in both dosages and both challenges against M. leprae infection. Lymphocytes proliferations of BCG-vaccinated splenocyte cultures in response to M. leprae lysate or BCG components (hsp65, 38 kD, 30 kD or 12 kD protein) were tested, and potent proliferative responses were seen in the cultures with M. leprae lysate and hsp65. Furthermore, gamma-IFN productions were positive in the cultures with M. leprae lysate or hsp65, but negative with other antigens. The production of gamma-IFN with hsp65 was never inhibited with polymyxin B, but inhibited with IL-10. These results show that BCG (Tokyo strain) is a useful vaccine for M. leprae infection in mice, and one of the components of BCG, hsp65, may be a effective antigen component for protection of M. leprae infection inducing Th1 type cytokine.

Immune response to heat-shock protein correlates with induction of insulitis in I-E alpha d transgenic NOD mice

To evaluate the correlation between heat-shock protein (HSP) and insulitis, we compared lymphocyte proliferative response to Mycobacterium leprae HSP65 of NOD mice with that of I-E alpha d transgenic NOD (I-E+NOD) mice, which show no insulitis. We found that splenocytes from 15-week-old NOD mice showed a more marked proliferative response to HSP than did those from age-matched I-E+NOD mice (P < 0.05). We then transferred splenocytes from 12-week-old NOD mice into I-E+NOD mice to induce insulitis in the recipients and examined antibody levels against HSP. By 6 weeks posttransfer, insulitis was successfully transferred to four out of five recipients of NOD splenocytes and antibody levels against HSP were significantly higher in the NOD splenocyte-transferred group than in controls, which showed no insulitis (P < 0.01). These results suggest that immune response to HSP correlates with insulitis in NOD mice. Our results support the assertion that HSP is a useful antigen for investigating the etiology of IDDM.

Antibody production to heat shock proteins with Mr 65 kD (HSP65) in cutaneous inflammation: a possible relation to focal infection

In order to correlate the immunomodulatory roles of homologous heat shock proteins with Mr 65 kD (HSP65) to skin diseases, antibody level to recombinant-HSP65 of Mycobacterium leprae was quantified with enzyme-linked immunosorbent assay (ELISA) in the sera of patients. In psoriasis, an insignificant increase was observed in anti-HSP65 IgG (0.111 +/- 0.053, mean +/- SD in 0D492 nm, n = 22), compared with a normal group (0.080 +/- 0.032, n = 9). However, psoriasis of acute guttate-type (PGA), which is often induced after tonsillar infection, showed a significant increase (0.178 +/- 0.032 n = 4, p <0.001), but psoriasis vulgaris did not (PV) (0.101 +/- 0.053, n = 12), nor generalized psoriasis pustulosa (PP) (0.087 +/- 0.025, n = 6). Similarly, patients with palmoplantar pustulosis (PPP) with tonsillar or periodontal infection showed significantly high anti-H5P65 IgG (0.230 +/- 0.065, n = 7, p <0.0001), compared with only a mild increase in PPP without suspected infectious foci (0.139 +/- 0.066, n = 13, p <0.05). Possible staphylococcal infection in the oral cavity was suggested by an additional ELISA assay to staphylococcal antigen: anti-staphylokinase IgG showed a significant increase in PPP with infectious foci (0.110 +/- 0.028 n = 3, p <0.01) compared with the normal group (0.039 +/- 0.014), while PPP without them showed only a mild change (0.060 +/- 0.017, n = 6, p <0.05). We assume that immunoreaction to H5P65 may be involved in psoriatic skin inflammation associated with focal infection.

Cloning and sequencing of the groESL homologue from Porphyromonas gingivalis

The homologue of groESL from Porphyromonas gingivalis was cloned and sequenced. Nucleotide sequencing suggested an operon containing two open reading frames (ORFs) homologous to groESL operon of Escherichia coli. The upstream ORF consisted of 267 bp corresponding to 89 amino acid residues. The downstream ORF consisted of 1635 bp corresponding to 545 amino acid residues.

Antibodies to 65Kd heat-shock protein were elevated in rheumatoid arthritis

Antibodies to 65Kd heat-shock protein (hsp) of mycobacterium leprae were measured by enzyme-linked immunosorbent assay (ELISA) in the three immunoglobulin classes in paired sera and synovial fluids of patients with rheumatoid arthritis (RA). Titers of anti-hsp antibody were expressed by optical density (OD) values for sera or indexes (OD values divided by amounts of immunoglobulin in each class) for synovial fluids and for their paired sera. Indexes of anti-hsp antibody were higher in synovial fluids than those in sera at 15/18 for IgG, 17/18 for IgA and 16/18 for IgM class. These results suggest the participation of anti-hsp antibodies to synovitis in RA.

Antibody to 65-kD stress protein (HSP65) of Mycobacterium leprae in various inflammatory skin diseases. A preliminary report

Cells from prokaryotes and eukaryotes exposed to environmental changes produce a series of highly homologous proteins called stress proteins, or heat shock proteins (HSPs). Recent investigators suggested that the reaction to the shared antigenic epitope between HSPs may link infections with induction of autoimmune processes. In the present study, antibody level to HSP with 65 kDa (HSP65) of Mycobacterium leprae was investigated with enzyme-linked immunosorbent assay (ELISA) in various skin diseases. Comparing to normal group (n = 9) including patients with nevus cell nevus showing 0.097 +/- 0.039 (mean +/- SD) in anti-HSP65 IgG level (OD492), 20 patients with palmoplantar pustulosis (PPP) and 22 with psoriasis demonstrated elevated (0.170 +/- 0.079, 0.111 +/- 0.053, respectively) level. Among them patients judged as focal infection-related PPP or psoriasis showed significantly higher level of anti-HSP65 (p < 0.01) than those without focal infection. Anaphylactoid purpura (0.125 +/- 0.085, n = 5), Behcet disease (0.178 +/- 0.045), atopic dermatitis (0.218 +/- 0.096, n = 13), urticaria (0.185 +/- 0.079, n = 30), and herpes zoster (0.193 +/- 0.092, n = 13) showed likewise elevated anti-HSP65 antibody. Similar tendency was found in anti-HSP65 IgM level but not in anti-HSP65 IgA. Western blotting confirmed specific immunoreaction bands to HSP65 in blood samples with high titer. Immunomodulation by stress proteins of bacterial or host cells is assumed in pathophysiology of inflammatory skin disorders, especially in relation to focal bacterial infection as observed in cases with PPP and psoriasis.

Immunological properties of ribosomal proteins from Mycobacterium bovis BCG

Two proteins with molecular mass 65 kDa, a heat shock protein, and an S1-like protein were found in a 30S ribosomal subunit from Mycobacterium bovis BCG. The 17-kDa protein in the 30S subunit was homologous to alpha-crystallin heat shock protein, and the 16-kDa protein in the 50S subunit was homologous to the L7/L12 protein. The latter provoked a strong delayed-type hypersensitivity reaction in the sensitized guinea pigs. The GroES-like protein (12 kDa) loosely associated with ribosomes.

Detection of heat shock protein in patients with insulin-dependent diabetes mellitus

We have investigated whether antibodies to heat shock protein (hsp) 65 are present in sera from patients with insulin-dependent diabetes mellitus by using Mycobacterium leprae hsp65. Fifty-two sera from patients with IDDM, 36 from patients with unclassified insulin-treated diabetes mellitus and 41 from normal healthy controls were examined by ELISA assay. Seventeen (32.7%) out of 52 IDDM sera and 10 (27.8%) out of unclassified insulin-treated diabetic sera were positive for anti-Mycobacterium (anti-M. leprae) hsp65 antibodies while none of the healthy control sera were positive. Based on western blot analysis, 12 of the 17 IDDM sera and 1 of 2 sera from the unclassified insulin-treated diabetics were positive for anti-M.leprae hsp65 antibodies while all normal control sera were negative. These results support the idea that hsp65 may play a role in the pathogenesis of IDDM. Future studies are necessary to elucidate the role of hsp65 in the pathogenesis of IDDM.

Presence in Kawasaki disease of antibodies to mycobacterial heat-shock protein HSP65 and autoantibodies to epitopes of human HSP65 cognate antigen

The central features of Kawasaki disease are immune activation and cytokine-mediated generalized vasculitis. To identify the predisposing factors, we examined the antibody response to BCG antigens, since reactivation of a previous BCG inoculation site is an early, specific manifestation of this disease. BCG antigens were separated on SDS-PAGE, transferred to membrane, and incubated with acute- and convalescent-phase sera of 21 patients with Kawasaki disease. Sera were also examined for the presence of antibodies to mycobacterial 65-kDa heat-shock protein (HSP65), and to its human homolog P1 antigen using synthetic peptides of nonhomologous region. To demonstrate the HSP65-sensitized T cells, in vitro proliferation assay was performed. All convalescent, but not acute phase, sera showed a strong antibody reactivity against 65-kDa protein. The reactivity was directed to recombinant HSP65. Non-cross-reactive sequences between rHSP65 and human HSP65 cognate were synthesized. The sera recognized these peptides of rHSP65 and autologous P1 antigen. Peripheral lymphocytes proliferated following the addition of rHSP65 (stimulation indices, 2.16-7.82; mean, 4.54). These findings suggest that HSP65 may be the most potent factor predisposing to Kawasaki disease, and that an autoreactivity to the epitope of the human HSP65 homolog may be related to the susceptibility to the disease.

Constitutive expression of 65-kDa heat shock protein (HSP65)-like immunoreactivity in cultured mouse oligodendrocytes

The expression of mycobacterial 65-kDa heat shock protein (HSP65)-like immunoreactivity in cultured mouse oligodendrocytes and astrocytes was investigated using three monoclonal antibodies (ML30, IA1, 3A) specific for the mycobacterial HSP65. In western blot analysis, these antibodies recognized the proteins with molecular weights approximately of 50-, 60-, and 70-kDa expressed in both heat-stressed and unstressed glial cells. When the cells were exposed to heat stress, the expression of both 50- and 70-kDa proteins was attenuated, whereas that of the 60-kDa protein was not affected. On immunocytochemical studies, an appreciable level of HSP65 immunolabelling was identified in most (> 90%) oligodendrocytes under both heat-stressed and unstressed conditions but only marginally detectable in most (> 95%) astrocytes. These results indicate that mouse oligodendrocytes in vitro express the mycobacterial HSP65-like immunoreactivity constitutively.

Overproduction, affinity purification and characterization of 65-kDa protein of Mycobacterium leprae in Escherichia coli

The 65-kDa protein of Mycobacterium leprae was produced in an Escherichia coli strain carrying a plasmid harboring the recloned gene coding for the protein. The protein was purified through affinity chromatography prepared with the IgG fraction of a monoclonal antibody which was prepared against the 65-kDa protein. The purified 65-kDa protein also reacted immunologically with the monoclonal antibody IIIE9, which recognizes the epitope for M. leprae, prepared by Buchanan, et al. BALB/c mice were inoculated with M. leprae and 4 months later were skin tested with the purified 65-kDa protein. Gross changes were observed at the skin-test site. The role of the protein in protective immunity against M. leprae foot pad infection in mice was also studied.

Characterization of antibody-reactive epitopes on the 65-kilodalton protein of Mycobacterium leprae

Twenty-three monoclonal antibodies (MAbs) prepared in seven different laboratories were studied, all of which recognized the 65-kilodalton (kDa) protein of Mycobacterium leprae as determined by Western blotting or gel radioimmunoassay or both. Fourteen of the MAbs recognized different epitopes, as evaluated by cross-competition studies using radiolabeled MAb and unlabeled inhibitors; the species specificity of these epitopes was defined by nitrocellulose dot blot immunoassays with bacterial sonic extract antigen preparations from 23 species of mycobacteria. Each of the 14 distinct MAbs recognized a 65-kDa protein produced by a lysogenized Escherichia coli Y1089 host containing cloned rDNA which included the gene for the M. leprae 65-kDa protein. Of the 14 distinct MAbs, 1 recognized an epitope found only on M. leprae, and the others recognized epitopes present on as few as 8 or as many as all 23 of the mycobacterial species studied. Identification of these distinct 65-kDa protein epitopes and use of the MAbs which recognize them should assist future structural studies of this protein and characterization of the T-cell reactive and serodiagnostically useful portions of the molecule.

Restored pathogenicity of attenuated Mycobacterium lepraemurium in mice

The ability of Mycobacterium lepraemurium (Mlm) to adhere to A31 cells in culture decreased with the number of passages of the bacilli on Ogawa egg-yolk medium. Pathogenic Mlm consistently grew in tissue culture cells but growth was not seen with attenuated Mlm isolated from a smooth colony. After prolonged incubation, attenuated Mlm became adapted to tissue culture growth. The pathogenicity of the attenuated bacilli was restored partially by the adaptation to tissue culture cells and restored almost completely by passage in mice. After restoration of pathogenicity by these methods, the Mlm formed rough-type colonies on Ogawa egg-yolk medium although the colonies were not completely of the rough type. Attenuated Mlm did not interfere with the growth of in vivo-derived Mlm in tissue culture or in mice.

Growth and drug sensitivity of M. lepraemurium by tissue culture applying monolayer and agar suspension technique

M. lepraemurium grow well in a Balb/c 3T3 recloned cell line (A31). In monolayer culture, the average generation time of M. lepraemurium in A31 cells was 5.3 to 9.4 days at 37 degrees C. A31 cells are very sensitive to infection with M. lepraemurium. Bacterial increases were readily apparent 30 days after inoculating 2 X 10(5) A31 cells in monolayer culture with only six bacilli. The intracellular bacilli were well transferred without apparent losses by host cell transfer. The growth of intracellular bacilli was inhibited by streptomycin 100 micrograms/ml, clindamycin 25 micrograms/ml, INH 5 micrograms/ml, and rifampin 5 micrograms/ml. When streptomycin or clindamycin was removed from the culture medium after 41 days of treatment and the cultivation continued in drug-free medium, the intracellular bacilli began to multiply once more without a lag period. When the intracellular bacilli were treated with INH for 35 days or rifampin for ten days, growth resumed, but only after lag periods after removal of these drugs. We utilized agar suspension techniques for the cultivation of host cells M. lepraemurium because normal cells or transformed cells ceased undergoing cell division and remained healthy for long periods of time in agar medium. M. lepraemurium grew well in A31, A31 transformed by polyoma virus, nude mouse foot pad, chick embryo, and human neuroblastoma cells, utilizing the agar suspension technique. The agar suspension cell culture method should provide useful clues for the cultivation of M. leprae.