DSM-IV post-traumatic stress disorder among World Trade Center responders 11-13 years after the disaster of 11 September 2001 (9/11).

BACKGROUND: Post-traumatic symptomatology is one of the signature effects of the pernicious exposures endured by responders to the World Trade Center (WTC) disaster of 11 September 2001 (9/11), but the long-term extent of diagnosed Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV) post-traumatic stress disorder (PTSD) and its impact on quality of life are unknown. This study examines the extent of DSM-IV PTSD 11-13 years after the disaster in WTC responders, its symptom profiles and trajectories, and associations of active, remitted and partial PTSD with exposures, physical health and psychosocial well-being. METHOD: Master's-level psychologists administered sections of the Structured Clinical Interview for DSM-IV and the Range of Impaired Functioning Tool to 3231 responders monitored at the Stony Brook University World Trade Center Health Program. The PTSD Checklist (PCL) and current medical symptoms were obtained at each visit. RESULTS: In all, 9.7% had current, 7.9% remitted, and 5.9% partial WTC-PTSD. Among those with active PTSD, avoidance and hyperarousal symptoms were most commonly, and flashbacks least commonly, reported. Trajectories of symptom severity across monitoring visits showed a modestly increasing slope for active and decelerating slope for remitted PTSD. WTC exposures, especially death and human remains, were strongly associated with PTSD. After adjusting for exposure and critical risk factors, including hazardous drinking and co-morbid depression, PTSD was strongly associated with health and well-being, especially dissatisfaction with life. CONCLUSIONS: This is the first study to demonstrate the extent and correlates of long-term DSM-IV PTSD among responders. Although most proved resilient, there remains a sizable subgroup in need of continued treatment in the second decade after 9/11.

Trajectories of PTSD risk and resilience in World Trade Center responders: an 8-year prospective cohort study.

BACKGROUND: Longitudinal symptoms of post-traumatic stress disorder (PTSD) are often characterized by heterogeneous trajectories, which may have unique pre-, peri- and post-trauma risk and protective factors. To date, however, no study has evaluated the nature and determinants of predominant trajectories of PTSD symptoms in World Trade Center (WTC) responders. METHOD: A total of 10835 WTC responders, including 4035 professional police responders and 6800 non-traditional responders (e.g. construction workers) who participated in the WTC Health Program (WTC-HP), were evaluated an average of 3, 6 and 8 years after the WTC attacks. RESULTS: Among police responders, longitudinal PTSD symptoms were best characterized by four classes, with the majority (77.8%) in a resistant/resilient trajectory and the remainder exhibiting chronic (5.3%), recovering (8.4%) or delayed-onset (8.5%) symptom trajectories. Among non-traditional responders, a six-class solution was optimal, with fewer responders in a resistant/resilient trajectory (58.0%) and the remainder exhibiting recovering (12.3%), severe chronic (9.5%), subsyndromal increasing (7.3%), delayed-onset (6.7%) and moderate chronic (6.2%) trajectories. Prior psychiatric history, Hispanic ethnicity, severity of WTC exposure and WTC-related medical conditions were most strongly associated with symptomatic trajectories of PTSD symptoms in both groups of responders, whereas greater education and family and work support while working at the WTC site were protective against several of these trajectories. CONCLUSIONS: Trajectories of PTSD symptoms in WTC responders are heterogeneous and associated uniquely with pre-, peri- and post-trauma risk and protective factors. Police responders were more likely than non-traditional responders to exhibit a resistant/resilient trajectory. These results underscore the importance of prevention, screening and treatment efforts that target high-risk disaster responders, particularly those with prior psychiatric history, high levels of trauma exposure and work-related medical morbidities.

Dimensional structure and course of post-traumatic stress symptomatology in World Trade Center responders.

BACKGROUND: Post-traumatic stress disorder (PTSD) in response to the World Trade Center (WTC) disaster of 11 September 2001 (9/11) is one of the most prevalent and persistent health conditions among both professional (e.g. police) and non-traditional (e.g. construction worker) WTC responders, even several years after 9/11. However, little is known about the dimensionality and natural course of WTC-related PTSD symptomatology in these populations. METHOD: Data were analysed from 10 835 WTC responders, including 4035 police and 6800 non-traditional responders who were evaluated as part of the WTC Health Program, a clinic network in the New York area established by the National Institute for Occupational Safety and Health. Confirmatory factor analyses (CFAs) were used to evaluate structural models of PTSD symptom dimensionality; and autoregressive cross-lagged (ARCL) panel regressions were used to examine the prospective interrelationships among PTSD symptom clusters at 3, 6 and 8 years after 9/11. RESULTS: CFAs suggested that five stable symptom clusters best represent PTSD symptom dimensionality in both police and non-traditional WTC responders. This five-factor model was also invariant over time with respect to factor loadings and structural parameters, thereby demonstrating its longitudinal stability. ARCL panel regression analyses revealed that hyperarousal symptoms had a prominent role in predicting other symptom clusters of PTSD, with anxious arousal symptoms primarily driving re-experiencing symptoms, and dysphoric arousal symptoms primarily driving emotional numbing symptoms over time. CONCLUSIONS: Results of this study suggest that disaster-related PTSD symptomatology in WTC responders is best represented by five symptom dimensions. Anxious arousal symptoms, which are characterized by hypervigilance and exaggerated startle, may primarily drive re-experiencing symptoms, while dysphoric arousal symptoms, which are characterized by sleep disturbance, irritability/anger and concentration difficulties, may primarily drive emotional numbing symptoms over time. These results underscore the importance of assessment, monitoring and early intervention of hyperarousal symptoms in WTC and other disaster responders.

Exposure, probable PTSD and lower respiratory illness among World Trade Center rescue, recovery and clean-up workers.

BACKGROUND: Thousands of rescue and recovery workers descended on the World Trade Center (WTC) in the wake of the terrorist attack of September 11, 2001 (9/11). Recent studies show that respiratory illness and post-traumatic stress disorder (PTSD) are the hallmark health problems, but relationships between them are poorly understood. The current study examined this link and evaluated contributions of WTC exposures. METHOD: Participants were 8508 police and 12 333 non-traditional responders examined at the WTC Medical Monitoring and Treatment Program (WTC-MMTP), a clinic network in the New York area established by the National Institute for Occupational Safety and Health (NIOSH). We used structural equation modeling (SEM) to explore patterns of association among exposures, other risk factors, probable WTC-related PTSD [based on the PTSD Checklist (PCL)], physician-assessed respiratory symptoms arising after 9/11 and present at examination, and abnormal pulmonary functioning defined by low forced vital capacity (FVC). RESULTS: Fewer police than non-traditional responders had probable PTSD (5.9% v. 23.0%) and respiratory symptoms (22.5% v. 28.4%), whereas pulmonary function was similar. PTSD and respiratory symptoms were moderately correlated (r=0.28 for police and 0.27 for non-traditional responders). Exposure was more strongly associated with respiratory symptoms than with PTSD or lung function. The SEM model that best fit the data in both groups suggested that PTSD statistically mediated the association of exposure with respiratory symptoms. CONCLUSIONS: Although longitudinal data are needed to confirm the mediation hypothesis, the link between PTSD and respiratory symptoms is noteworthy and calls for further investigation. The findings also support the value of integrated medical and psychiatric treatment for disaster responders.

Early and specific antibody response to OspA in Lyme Disease.

Borrelia burgdorferi (Bb), the cause of Lyme disease, has appeared not to evoke a detectable specific antibody response in humans until long after infection. This delayed response has been a biologic puzzle and has hampered early diagnosis. Antibody to the abundant organism-specific outer surface proteins, such as the 31-kD OspA, has rarely been detected less than 6 mo after infection. Antibody to a less organism-specific 41-kD flagellin protein, sharing common determinants with other bacteria and thus limiting its diagnostic potential, may appear after 4 to 6 wks. To investigate our hypothesis that specific antibody to OspA may actually be formed early but remain at low levels or bound in immune complexes, we analyzed serum samples from patients with concurrent erythema migrans (EM). This is the earliest sign of Lyme disease and occurs in 60-70% of patients, generally 4-14 d after infection. We used less conventional but more sensitive methods: biotin-avidin Western blots and immune complex dissociation techniques. Antibody specificity was confirmed with recombinant OspA. Specific complexed antibody to whole Bb and recombinant OspA was detected in 10 of 11 of the EM patients compared to 0 of 20 endemic area controls. IgM was the predominant isotype to OspA in these EM patients. Free IgM to OspA was found in half the EM cases. IgM to OspA was also detected in 10 of 10 European patients with EM who also had reactive T cells to recombinant OspA. In conclusion a specific antibody response to OspA occurs early in Lyme disease. This is likely to have diagnostic implications.

Simultaneous expression of Borrelia OspA and OspC and IgM response in cerebrospinal fluid in early neurologic Lyme disease.

Lyme disease is the major tick-borne disease, caused by Borrelia burgdorferi (Bb). Neurological involvement is common in all stages. In vivo expression of Bb antigens (Ags) and the immune response to them has not been well investigated in the cerebrospinal fluid (CSF). Upregulation of outer surface protein (Osp) C and concomitant downregulation of OspA before tick inoculation of the spirochete has been reported in skin and blood in animals. CSF OspA Ag in early disease suggests otherwise in CSF. Early Ag expression and IgM response in human CSF was investigated here. Paired CSF and serum was collected from 16 early, predominantly erythema migrans Lyme disease patients with neurologic problems, 13 late Lyme disease patients, and 19 other neurologic disease (OND) controls. Samples were examined for IgM reactivity to recombinant Bb-specific Osps using ELISA and immunoblot. Of 12 early Lyme disease patients with neurologic involvement with both CSF and serum IgM against OspC, 7 (58%) had IgM to OspA (n = 5) or OspB (n = 2) that was restricted to the CSF, not serum. Overall, 12 of 16 (75%) of these early Lyme disease patients with neurologic involvement had CSF and serum IgM against OspC. Only 3 of 13 (23%) late Lyme disease patients and none of 19 OND controls had CSF IgM directed against OspC. In conclusion, in CSF, OspC and OspA can be coexpressed, and IgM response to them occurs in early Lyme disease patients with neurologic involvement. This biologic finding may also provide a discriminating marker for CNS infection in Lyme disease.

Inhibition of cytoplasmic and organellar protein synthesis in Toxoplasma gondii. Implications for the target of macrolide antibiotics.

We investigated potential targets for the activity of protein synthesis inhibitors against the protozoan parasite Toxoplasma gondii. Although nanomolar concentrations of azithromycin and clindamycin prevent replication of T. gondii in both cell culture and in vivo assays, no inhibition of protein labeling was observed in either extracellular or intracellular parasites treated with up to 100 microM drug for up to 24 h. Quantitative analysis of > 300 individual spots on two-dimensional gels revealed no proteins selectively depleted by 100 microM azithromycin. In contrast, cycloheximide inhibited protein synthesis in a dose-dependent manner. Nucleotide sequence analysis of the peptidyl transferase region from genes encoding the large subunit of the parasite's ribosomal RNA predict that the cytoplasmic ribosomes of T. gondii, like other eukaryotic ribosomes, should be resistant to macrolide antibiotics. Combining cycloheximide treatment with two-dimensional gel analysis revealed a small subset of parasite proteins likely to be synthesized on mitochondrial ribosomes. Synthesis of these proteins was inhibited by 100 microM tetracycline, but not by 100 microM azithromycin or clindamycin. Ribosomal DNA sequences believed to be derived from the T. gondii mitochondrial genome predict macrolide/lincosamide resistance. PCR amplification of total T. gondii DNA identified an additional class of prokaryotic-type ribosomal genes, similar to the plastid-like ribosomal genes of the Plasmodium falciparum. Ribosomes encoded by these genes are predicted to be sensitive to the lincosamide/macrolide class of antibiotics, and may serve as the functional target for azithromycin, clindamycin, and other protein synthesis inhibitors in Toxoplasma and related parasites.

An epigenome-wide DNA methylation study of PTSD and depression in World Trade Center responders.

Previous epigenome-wide association studies (EWAS) of posttraumatic stress disorder (PTSD) and major depressive disorder (MDD) have been inconsistent. This may be due to small sample sizes, and measurement and tissue differences. The current two EWA analyses of 473 World Trade Center responders are the largest to date for both PTSD and MDD. These analyses investigated DNA methylation patterns and biological pathways influenced by differentially methylated genes associated with each disorder. Methylation was profiled on blood samples using Illumina 450 K Beadchip. Two EWA analyses compared current versus never PTSD, and current versus never MDD, adjusting for cell types and demographic confounders. Pathway and gene set enrichment analyses were performed to understand the complex biological systems of PTSD and MDD. No significant epigenome-wide associations were found for PTSD or MDD at an FDR P<0.05. The majority of genes with differential methylation at a suggestive threshold did not overlap between the two disorders. Pathways significant in PTSD included a regulator of synaptic plasticity, oxytocin signaling, cholinergic synapse and inflammatory disease pathways, while only phosphatidylinositol signaling and cell cycle pathways emerged in MDD. The failure of the current EWA analyses to detect significant epigenome-wide associations is in contrast with disparate findings from previous, smaller EWA and candidate gene studies of PTSD and MDD. Enriched gene sets involved in several biological pathways, including stress response, inflammation and physical health, were identified in PTSD, supporting the view that multiple genes play a role in this complex disorder.

Inhibition of mouse natural killer cell activity by zinc.

The effect of zinc on mouse natural killer (NK) cell activity was evaluated. The inhibition of NK cell activity with zinc was dependent on the concentration of zinc added (range tested: 0-40 micrograms zinc/ml) and occurred at both effector-to-target ratios tested. Zinc-induced inhibition of NK activity was observed with the use of peritoneal or splenic effector cells on Toxoplasma gondii-augmented NK activity. Maximal inhibition of activity was noted when zinc was present for the entire assay period. Inhibition was present but less marked with pretreatment of effector cells with zinc. Pretreatment of target cells with zinc had no measurable effect on NK cytotoxicity. Effector-to-target cell binding as measured by single-cell assays was not significantly altered by zinc. These results indicate that zinc is a potent inhibitor of NK activity.

Evidence for an alpha-helical epitope on outer surface protein A from the Lyme disease spirochete, Borrelia burgdorferi: an application of steady-state and time-resolved fluorescence quenching techniques.

Outer surface protein A (OspA) is a major antigen of Borrelia burgdorferi, the etiological agent of Lyme disease. A recombinant form of OspA (OspA-257) from B. burgdorferi, strain B31, contains 257 amino acids and a single tryptophan residue at position 216 (Trp-216). Mapping studies indicate that Trp-216 is involved in the epitope for the agglutinating monoclonal antibody 105.5. However, the fluorescence emission maximum of the native protein is 330 nm, indicating that Trp-216 is not solvent-exposed. Primary structure analysis suggests an alpha-helical conformation for residues approx. 204-217, which, if located on the protein surface, would allow Trp-216 to be buried, while leaving hydrophilic residues on the opposite side of the helix exposed. This helix would place Lys-212 within approx. 6 A of Trp-216; the presence of such a positively-charged residue can, in principle, be ascertained from fluorescence quenching studies. Stern-Volmer plots confirm that Trp-216 is indeed buried in the native protein, but is readily accessible to the small polar quencher, acrylamide. Furthermore, the dominant component of the fluorescence emission shows only weak dynamic quenching by the positively-charged quencher, Cs+, while the minor component undergoes static quenching by I-, indicating the proximity of a positively-charged residue. These data are consistent with the existence of an alpha-helix from residues 204-217 in the predicted orientation at the protein surface, hence indicating the structure of the antigenic determinant.

NMR identification of epitopes of Lyme disease antigen OspA to monoclonal antibodies.

Outer surface protein A (OspA) from the Lyme disease spirochete Borrelia burgdorferi has been a focus of vaccine development. We have identified epitopes of OspA to two monoclonal antibodies (mAbs) by comparing NMR chemical shifts of free OspA and those in Fab complexes. Deuteration of non-labile protons in OspA extended the size limit of this technique so that it was applicable to the 78 kDa complexes of OspA and the Fab fragment. The epitope identified by NMR to an mAb, 184.1, agrees well with that previously defined by the crystal structure of the same complex, indicating the ability of the NMR method to accurately map an epitope in a large protein complex. The technique mapped the epitope to mAb 336, a mAb of clinical interest, to a region centered at the C-terminal alpha-helix. The results provides a basis for rational design of OspA-based Lyme disease vaccines.

Structural identification of a key protective B-cell epitope in Lyme disease antigen OspA.

Outer surface protein A (OspA) is a major lipoprotein of the Borrelia burgdorferi spirochete, the causative agent of Lyme disease. Vaccination with OspA generates an immune response that can prevent bacterial transmission to a mammalian host during the attachment of an infected tick. However, the protective capacity of immune sera cannot be predicted by measuring total anti-OspA antibody. The murine monoclonal antibody LA-2 defines an important protective B-cell epitope of OspA against which protective sera have strong levels of reactivity. We have now mapped the LA-2 epitope of OspA using both NMR chemical-shift perturbation measurements in solution and X-ray crystal structure determination. LA-2 recognizes the three surface-exposed loops of the C-terminal domain of OspA that are on the tip of the elongated molecule most distant from the lipid-modified N terminus. The structure suggests that the natural variation at OspA sequence position 208 in the first loop is a major limiting factor for antibody cross-reactivity between different Lyme disease-causing Borrelia strains. The unusual Fab-dominated lattice of the crystal also permits a rare view of antigen flexibility within an antigen:antibody complex. These results provide a rationale for improvements in OspA-based vaccines and suggest possible designs for more direct tests of antibody protective levels in vaccinated individuals.

Genetic diversity of ospC in a local population of Borrelia burgdorferi sensu stricto.

The outer surface protein, OspC, is highly variable in Borrelia burgdorferi sensu stricto, the agent of Lyme disease. We have shown that even within a single population OspC is highly variable. The variation of ospA and ospC in the 40 infected deer ticks collected from a single site on Shelter Island, New York, was determined using PCR-SSCP. There is very strong apparent linkage disequilibrium between ospA and ospC alleles, even though they are located on separate plasmids. Thirteen discernible SSCP mobility classes for ospC were identified and the DNA sequence for each was determined. These sequences, combined with 40 GenBank sequences, allow us to define 19 major ospC groups. Sequences within a major ospC group are, on average, <1% different from each other, while sequences between major ospC groups are, on average, approximately 20% different. The tick sample contains 11 major ospC groups, GenBank contains 16 groups, with 8 groups found in both samples. Thus, the ospC variation within a local population is almost as great as the variation of a similar-sized sample of the entire species. The Ewens-Watterson-Slatkin test of allele frequency showed significant deviation from the neutral expectation, indicating balancing selection for these major ospC groups. The variation represented by major ospC groups needs to be considered if the OspC protein is to be used as a serodiagnostic antigen or a vaccine.

Acute Toxoplasma infection among family members of patients with acute lymphadenopathic toxoplasmosis.

Studies were performed to determine how frequently acute infections with Toxoplasma gondii occur among family members of patients with acute acquired lymphadenopathic toxoplasmosis. In five of the nine families studied, more than one family member had serologic evidence of recent acute infection with T gondii. In three of the families, the immunoglobulin M and immunoglobulin G antibody titers to T gondii among infected family members were similar irrespective of whether lymphadenopathy was present. Lymphadenopathy developed in one family member in each of two families (families VIII and IX) three and eight months after lymphadenopathy had developed in the index case (proband). These results suggest that common-source outbreaks occur with surprising frequency among family members of patients with lymphadenopathic toxoplasmosis and that the humoral response is similar with different manifestations of the infection.

Dose-escalation, phase I/II study of azithromycin and pyrimethamine for the treatment of toxoplasmic encephalitis in AIDS.

OBJECTIVE: To assess the safety, tolerance and activity of increasing doses of azithromycin in combination with pyrimethamine for the treatment of toxoplasmic encephalitis (TE) in patients with AIDS. DESIGN: A phase I/II dose-escalation study of oral azithromycin in combination with pyrimethamine. SETTING: Eight clinical sites in the United States. PATIENTS: Forty-two adult HIV-infected patients with confirmed or presumed acute TE. METHODS: Patients were enrolled into three successive cohorts receiving azithromycin 900, 1200 and 1500 mg a day with pyrimethamine as induction therapy. The induction period was 6 weeks followed by 24 weeks of maintenance therapy. MAIN OUTCOME MEASURES: Patient response was evaluated clinically and radiologically. RESULTS: Of the 30 evaluable patients, 20 (67%) responded to therapy during the induction period. Ten experienced disease progression. Of the 15 patients who received maintenance therapy, seven (47%) relapsed. Six patients discontinued treatment during the induction period as a result of reversible toxicities. Treatment-terminating adverse events occurred most frequently among the patients receiving the 1500 mg dose. CONCLUSION: The combination of azithromycin (900-1200 mg a day) and pyrimethamine may be useful as an alternative therapy for TE among patients intolerant of sulfonamides and clindamycin, but maintenance therapy with this combination was associated with a high relapse rate. The combination was safe, but low-grade adverse events were common.

Lyme neuroborreliosis: central nervous system manifestations.

We evaluated 85 patients with serologic evidence of Borrelia burgdorferi infection. Manifestations included encephalopathy (41), neuropathy (27), meningitis (2), multiple sclerosis (MS) (6), and psychiatric disorders (3). We performed lumbar punctures in 53, brain MRI in 33, and evoked potentials (EPs) in 33. Only patients with an MS-like illness had abnormal EPs, elevated IgG index, and oligoclonal bands in the cerebrospinal fluid. Twelve of 18 patients with encephalopathy, meningitis, or focal CNS disease had evidence of intrathecal synthesis of anti-B burgdorferi antibody, compared with no patients with either MS-like or psychiatric illnesses, and only 2/24 patients with neuropathy. MRIs were abnormal in 7/17 patients with encephalopathy, 5/6 patients with an MS-like illness, and no others. We conclude that (1) intrathecal concentration of specific antibody is a useful marker of CNS B burgdorferi infection; (2) Lyme disease causes an encephalopathy, probably due to infection of the CNS; (3) MS patients with serum immunoreactivity against B burgdorferi lack evidence of CNS infection with this organism.

Detection of Borrelia burgdorferi-specific antigen in antibody-negative cerebrospinal fluid in neurologic Lyme disease.

OBJECTIVE: To determine the potential of detection in CSF of specific Borrelia burgdorferi antigen, OspA, as a marker of infection in neurologic Lyme disease and compare this with the detection of antibody. DESIGN: CSF from 83 neurologic patients in an area highly endemic for Lyme disease was examined prospectively for (1) OspA by antigen capture ELISA and Western blot employing monoclonal antibodies, and for (2) B burgdorferi antibodies by ELISA. RESULTS: Of the 35 of 83 (42%) patients who were positive for OspA antigen in their CSF, 15 (43%) were antigen positive despite being antibody-negative in CSF. Seven of these 15 (47%) had otherwise normal routine CSF analyses. Six of these 15 (40%) patients met strict CDC surveillance criteria for Lyme disease; four (27%) patients had seroconversion coincident with new neurologic problems; and three (20%) with characteristic syndromes for Lyme disease were seronegative, but had complexed antibody to B burgdorferi. The final two patients (13%) were seropositive and had unexplained neurologic problems not characteristic of Lyme disease. CONCLUSIONS: B burgdorferi antigen can be detected in CSF that is otherwise normal by conventional methodology, and can be present without positive CSF antibody. Since CSF antigen implies intrathecal seeding of the infection, the diagnosis of neurologic infection by B burgdorferi should not be excluded solely on the basis of normal routine CSF or negative CSF antibody analyses.

IgM and IgG antibody response in two immunosuppressed patients with Legionnaires' disease. Evidence of reactivation of latent infection.

Two patients in whom pneumonia due to Legionella pneumophila developed while they were receiving immunosuppressive therapy had serologic evidence of prior infection with the same serogroup of L. pneumophila two and eight months prior to their clinical pneumonia. This suggests that the pneumonia in these patients may have been due to the reactivation of a latent infection, possibly due to their immunosuppressed state. A new enzyme-linked immunosorbent assay (ELISA) was developed to detect IgG and IgM antibodies to L. pneumophila, and the kinetics of these antibody responses were useful diagnostically.

The effects of cyclosporine on Toxoplasma gondii in vivo and in vitro.

We examined the effect of cyclosporine on Toxoplasma infection in vivo and in vitro. Administration to mice of 150 mg/kg/day cyclosporine variably affected mortality in four separate experiments. IgG (Sabin-Feldman dye test) and IgM enzyme-linked immunosorbent assay antibody titers were significantly depressed in mice treated with cyclosporine. These results suggested the possibility that cyclosporine possesses anti-Toxoplasma activity. Thus, macrophages were incubated with cyclosporine before and after infection with Toxoplasma. Treatment with 0.5, 1, and 5 micrograms cyclosporine/ml during or after challenge of macrophage monolayers with Toxoplasma inhibited replication of Toxoplasma (and resulted in killing of Toxoplasma). The effect of cyclosporine on development of activated macrophages was studied. Cyclosporine administered to mice at a dose of 150 mg/kg/day neither accelerated nor delayed activation of macrophages (assessed by inhibition of Toxoplasma replication in vitro) by i.v. injection of either Corynebacterium parvum or Toxoplasma. Cyclosporine affects mortality variably in murine toxoplasmosis, depresses synthesis of IgG and IgM Toxoplasma antibody in vivo, does not prevent activation of macrophages in vivo, and possesses anti-Toxoplasma activity in vitro and perhaps in vivo. Cyclosporine may be the preferred immunosuppressive agent for recipients of an organ transplant who are at high risk for toxoplasmosis (e.g., seronegative recipients who have received organ from seropositive donors).

Cross-reactive antigenic domains of the flagellin protein of Borrelia burgdorferi.

The p41 flagellin of Borrelia burgdorferi is the most common antigen recognized by serum of patients with Lyme borreliosis. This antigen shares amino acid homology, particularly in the amino and carboxy termini, with periflagellar antigens found in other microorganisms including Treponema pallidum. We cloned and expressed the p41 open reading frame in Escherichia coli and expressed it both as TrpE fusion and full-length unfused proteins. Also, we generated deletion constructs of various portions of the gene. Sera from patients with late Lyme borreliosis and secondary syphilis were used to identify the recombinant proteins by immunoblot analysis. Sera from 26 patients with Lyme borreliosis, 20 with secondary syphilis and 10 controls were used to identify cross-reactive domains of the B. burgdorferi flagellin. The variable region (amino acids 131-234) of the protein was recognized by 59% (15/26) of patients with late Lyme borreliosis compared to 30% (6/20) of patients with secondary syphilis and no (0/10) control patients. It appears that cross-reactive epitopes between B. burgdorferi and T. pallidum extend to the variable region of the flagellin.