Mycoplasma corogypsi-associated polyarthritis and tenosynovitis in black vultures (Coragyps atratus)

Three wild American black vultures (Coragyps atratus) were presented to rehabilitation centers with swelling of multiple joints, including elbows, stifles, hocks, and carpal joints, and of the gastrocnemius tendons. Cytological examination of the joint fluid exudate indicated heterophilic arthritis. Radiographic examination in 2 vultures demonstrated periarticular soft tissue swelling in both birds and irregular articular surfaces with subchondral bone erosion in both elbows in 1 bird. Prolonged antibiotic therapy administered in 2 birds did not improve the clinical signs. Necropsy and histological examination demonstrated a chronic lymphoplasmacytic arthritis involving multiple joints and gastrocnemius tenosynovitis. Articular lesions varied in severity and ranged from moderate synovitis and cartilage erosion and fibrillation to severe synovitis, diffuse cartilage ulceration, subchondral bone loss and/or sclerosis, pannus, synovial cysts, and epiphyseal osteomyelitis. No walled bacteria were observed or isolated from the joints. However, mycoplasmas polymerase chain reactions were positive in at least 1 affected joint from each bird. Mycoplasmas were isolated from joints of 1 vulture that did not receive antibiotic therapy. Sequencing of 16S rRNA gene amplicons from joint samples and the mycoplasma isolate identified Mycoplasma corogypsi in 2 vultures and was suggestive in the third vulture. Mycoplasma corogypsi identification was confirmed by sequencing the 16S-23S intergenic spacer region of mycoplasma isolates. This report provides further evidence that M. corogypsi is a likely cause of arthritis and tenosynovitis in American black vultures. Cases of arthritis and tenosynovitis in New World vultures should be investigated for presence of Mycoplasma spp, especially M. corogypsi.

Declining amphibian populations: the problem of separating human impacts from natural fluctuations

Reports of declining amphibian populations in many parts of the world are numerous, but supporting long-term census data are generally unavailable. Census data from 1979 to 1990 for three salamander species and one frog species at a breeding pond in South Carolina showed fluctuations of substantial magnitude in both the size of breeding populations and in recruitment of juveniles. Breeding population sizes exhibited no overall trend in three species and increased in the fourth. Recent droughts account satisfactorily for an increase in recruitment failures. These data illustrate that to distinguish between natural population fluctuations and declines with anthropogenic causes may require long-term studies.

Intravenous immunoglobulin products contain neutralizing antibodies to vaccinia

BACKGROUND AND OBJECTIVES

Individuals with primary or secondary immune-deficiency diseases may be at risk for vaccinia infection if widespread smallpox-immunization programmes are implemented in the United States of America (USA) for bioterrorism preparedness. The objective of this study was to determine whether commercial immune globulin (intravenous, human) products contain biologically active antibodies to vaccinia that have the potential to protect people, with immune deficiencies, from complications of vaccinia.

MATERIALS AND METHODS

Eight currently United States (US)-licensed and two European intravenous immunoglobulin (IVIG) products were tested in a vaccinia plaque-reduction neutralization assay. The in vivo activity of five of these lots was assessed in severely immune-deficient mice.

RESULTS

All tested products contained neutralizing anti-vaccinia activity, in vitro and in vivo.

CONCLUSIONS

The use of IVIG by individuals with inherited or acquired humoral immune deficiencies may provide some protection if they are inadvertently exposed to vaccinia.

Ontogeny of Th1 memory responses against a Brucella abortus conjugate

Protective immune responses to intracellular pathogens such as Brucella abortus are characteristically Th1-like. Recently we demonstrated that heat-killed B. abortus (HKBa), a strong Th1 stimulus, conjugated to ovalbumin (HKBA-OVA), but not B. abortus alone, can alter the antigen-specific cytokine profile from Th2- to Th1-like. In this report we study the ability of a single injection of B. abortus to switch a Th2 to a Th1 response in immature mice. One-day- and 1-week-old mice were given a single injection of B. abortus in the absence or presence of OVA, and at maturity mice were challenged with an allergenic preparation, OVA with alum (OVA-A). B. abortus given without OVA did not diminish the subsequent Th2 response in either age group. In contrast, mice receiving a single injection of B. abortus-OVA at the age of 1 week, but not those injected at the age of 1 day, had reversal of the ratio of OVA-specific Th1 to Th2 cells and decreased immunoglobulin E levels after allergen challenge as adults. Within 6 h both 1-day- and 1-week-old mice expressed interleukin-12 p40 mRNA following either B. abortus or B. abortus-OVA administration. However, only the 1-week-old mice exhibited increased expression of gamma interferon (IFN-gamma) mRNA. The absence of the early IFN-gamma response in 1-day-old mice may explain their inability to generate a Th1 memory response. These results suggest that at early stages of immune development, responses to intracellular bacteria may be Th2- rather than Th1-like. Furthermore, they suggest that the first encounter with antigen evokes either a Th1- or a Th2-like response which becomes imprinted, so that subsequent memory responses conform to the original Th bias. This has implications for protection against infectious agents and development of allergic responses.

Protection from experimental endotoxemia by a recombinant adeno-associated virus encoding interleukin 10

BACKGROUND

Interleukin 10 (IL-10) is a homodimeric cytokine that shows considerable clinical promise. Adeno-associated virus (AAV) vectors appear increasingly useful for in vivo gene-transfer applications.

METHODS

A recombinant AAV type 2 vector encoding human IL-10 (rAAVhIL10) was constructed by using an adenoviral-free, three-plasmid co-transfection. Cytokine production was measured by using an enzyme-linked immunosorbent assay. Endotoxic shock was induced by lipopolysaccharide (LPS) injection.

RESULTS

As media from rAAVhIL10-infected COS cells caused a dose-dependent blockade of IL-12 secretion from spleen cells of IL-10 knockout (KO) mice challenged with Brucella abortus, it was clear that vector-derived hIL-10 was biologically active in vitro. Intravenous or intramuscular administration of relatively modest levels of rAAVhIL10 (10(10) genomes) to IL-10 KO mice resulted in hIL-10 secretion into the bloodstream, which, at 8 weeks, gave median serum levels of 0.9 and 0.45 pg/ml, respectively. Acute endotoxic shock led to a 33% mortality rate, and severe morbidity, in control IL-10 KO mice, whereas no mortality and little morbidity were seen in IL-10 KO mice given rAAVhIL10 7 weeks earlier.

CONCLUSIONS

The findings demonstrate that a modest dose of rAAVhIL10 administered in vivo provides long-term protection against LPS-induced endotoxic shock in a murine model. Thus, this vector may be useful for clinical applications requiring sustained IL-10 expression, for example in the treatment of several autoimmune diseases.

IL-12 induction by a TH1-inducing adjuvant in vivo: dendritic cell subsets and regulation by IL-10

IL-12 induction is critical for immune responses against many viruses and intracellular bacterial pathogens. Recent studies suggest that IL-12-secreting dendritic cells (DC) are potent Th1-inducing APC. However, controversy exists concerning the function of DC subsets. Murine studies have suggested that CD8(+) DC preferentially induce Th1 responses, whereas CD8(-) DC induce Th2 development; in this model, different DC subsets prime different responses. Alternatively, the propensity of DC subsets to prime a Th1 response could depend upon the type of initial stimulus. We used a prototypic Th1-inducing adjuvant, heat-killed Brucella abortus (HKBA) to assess stimulation of DC subsets, relationship between Ag burden and IL-12 production, and down-regulation of DC subset IL-12 production by IL-10. In this study, we show that DC were sole producers of IL-12, although most HKBA uptake was by splenic macrophages and granulocytes. More CD8(-) than CD8(+) DC produced IL-12 after HKBA challenge, whereas only CD8(+) DC produced IL-12 after injection of another Th1-promoting microbial substance, soluble Toxoplasma gondii Ags. Studies in IL-10-deficient mice revealed that IL-10 down-regulates frequency and duration of IL-12 production by both DC subsets. In the absence of IL-10, IL-12 expression is enabled in CD11c(low) cells, but not in macrophages or granulocytes. These findings support the concept of DC as the major IL-12 producers in spleens, but challenge the notion that CD8(+) and CD8(-) DC are destined to selectively induce Th1 or Th2 responses, respectively. Thus, the nature of the stimulating substance is important in determining which DC subsets are activated to produce IL-12.

Immunoglobulin G3 from polyclonal human immunodeficiency virus (HIV) immune globulin is more potent than other subclasses in neutralizing HIV type 1

Passive antibody prophylaxis against human immunodeficiency virus type 1 (HIV-1) has been accomplished in primates, suggesting that this strategy may prove useful in humans. While antibody specificity is crucial for neutralization, other antibody characteristics, such as subclass, have not been explored. Our objective was to compare the efficiencies of immunoglobulin G (IgG) subclasses from polyclonal human HIV immune globulin (HIVIG) in the neutralization of HIV-1 strains differing in coreceptor tropism. IgG1, IgG2, and IgG3 were enriched from HIVIG by using protein A-Sepharose. All three subclasses bound major HIV-1 proteins, as shown by Western blot assay and enzyme-linked immunosorbent assay. In HIV-1 fusion assays using X4, R5, or X4R5 envelope-expressing effector cells, IgG3 more efficiently blocked fusion. In neutralization assays with cell-free viruses using X4 (LAI, IIIB), R5 (BaL), and X4R5 (DH123), a similar hierarchy of neutralization was found: IgG3 > IgG1 > IgG2. IgG3 has a longer, more flexible hinge region than the other subclasses. To test whether this is important, IgG1 and IgG3 were digested with pepsin to generate F(ab')(2) fragments or with papain to generate Fab fragments. IgG3 F(ab')(2) fragments were still more efficient in neutralization than F(ab')(2) of IgG1. However, Fab fragments of IgG3 and IgG1 demonstrated equivalent neutralization capacities and the IgG3 advantage was lost. These results suggest that the IgG3 hinge region confers enhanced HIV-neutralizing ability. Enrichment and stabilization of IgG3 may therefore lead to improved HIVIG preparations. The results of this study have implications for the improvement of passive immunization with polyclonal or monoclonal antibodies and suggest that HIV-1 vaccines which induce high-titer IgG3 responses could be advantageous.

Immunity and protection against Brucella abortus

Brucella abortus is an intracellular pathogen that causes disease in cattle and in humans. The response against B. abortus involves the whole gamut of the immune system, from innate to adaptive immunity resulting from stimulation of antigen-presenting cells, NK cells, CD4(+) and CD8(+) T cells, and B cells.

Induction and regulation of Th1-inducing cytokines by bacterial DNA, lipopolysaccharide, and heat-inactivated bacteria

Th1 immune responses, characterized by production of gamma interferon (IFN-gamma), are associated with protective immunity to viruses and intracellular bacteria. Heat-killed Brucella abortus promotes secretion of Th1-inducing cytokines such as interleukin-12 (IL-12) and IFN-gamma and has been used as a carrier to induce Th1 responses to vaccines. To explore which bacterial constituents could mediate this response and how it is regulated, murine spleen cells were cultured with B. abortus derived DNA, lipopolysaccharide (LPS), or whole killed organisms. Each constituent induced similar, substantial amounts of IL-10. However, only B. abortus and B. abortus DNA induced high levels of IFN-gamma and IL-12. B. abortus and B. abortus DNA-stimulated IL-12 production was maximal by 6 to 18 h, while IL-10 production steadily accumulated over this time period. These kinetics suggested that IL-10 may eventually downmodulate the Th1-like cytokine response to B. abortus and B. abortus DNA, which was confirmed by using neutralizing antibody. In the absence of IL-10, B. abortus LPS induced strong IFN-gamma responses, but IL-12 p70 levels were still undetectable from BALB/c spleen cells. LPS induced IL-12 if the spleen cells were primed with IFN-gamma and IL-10 was neutralized, indicating that LPS can stimulate IL-12 production under the most favorable conditions. Responses to Escherichia coli LPS and DNA mirrored the responses to B. abortus components, suggesting that immune effects observed with these constituents may be generalizable to many microbial species. In vivo experiments demonstrated the same hierarchy of responses for IL-12 production. These findings support the likelihood that microbial components, if used as carriers or adjuvants, can differ substantially in their ability to effect a Th1 response.

Post-traumatic migration and emergence of a novel cell line upon the ependymal surface of the third cerebral ventricle in the adult mammalian brain

This investigation describes the migration and emergence of significant numbers of what appear to be neuron-like cells upon the surface of the median eminence of the adult rodent neurohypophyseal system of the endocrine hypothalamus following the trauma of hypophysectomy. These cells appear to migrate through the neuropil of the underlying median eminence and emerge in large numbers upon the surface of the third cerebral ventricle within 7 days following hypophysectomy (axotomy) of supraoptic (SON) and paraventricular neurites (PVN) of the adult neurohypophyseal system. Previous investigations have demonstrated regeneration of the neural stem and neural lobe in a variety of mammalian species (Adams et al., J Comp Neurol, 1969;135:121-144; Beck et al., Neuroendocrinology, 1969;5:161-182; Scott et al., Exp Neurol, 1995;131-1:23-39; Scott and Hansen, Vir Med 1997;124:249-261). It also has been demonstrated that the process of regeneration is invariably accompanied by the up-regulation of nitric oxide synthase (NOS), the enzyme that catalyzes arginine to nitric oxide (NO) and that both neurohypophyseal regeneration, as well as migration and emergence of neuron-like cells upon the surface of the adjacent third cerebral ventricle, is associated with the up-regulation of NOS and increased expression of NO. It also has been amply demonstrated that this entire process of neurohypophyseal regeneration and cell migration is completely inhibited by the introduction of the antagonist of nitric oxide, namely, nitroarginine (Scott et al., Exp Neurol, 1995;131-1:23-39; Scott and Hansen, Vir Med, 1997;124:249-261). The emergence and migratory dynamics of this novel cell line upon the floor of the rodent third cerebral ventricle are discussed with respect to the role of the ubiquitous free radical NO and the implications and potential clinical applications of neuronal migration following trauma in the human central nervous system (CNS).

Down-regulation of Th2 responses by Brucella abortus, a strong Th1 stimulus, correlates with alterations in the B7.2-CD28 pathway

Down-regulation of the Th2-like response induced by ovalbumin-alum (OVA/alum) immunization by heat-killed Brucella abortus was not reversed by anti-IL-12 antibody treatment or in gamma interferon (IFN-gamma) knockout mice, suggesting that induction of Th1 cytokines was not the only mechanism involved in the B. abortus-mediated inhibition of the Th2 response to OVA/alum. The focus of this study was to determine whether an alternative pathway involves alteration in expression of costimulatory molecules. First we show that the Th2-like response to OVA/alum is dependent on B7.2 interaction with ligand since it can be abrogated by anti-B7.2 treatment. Expression of costimulatory molecules was then studied in mice immunized with OVA/alum in the absence or presence of B. abortus. B7.2, but not B7.1, was up-regulated on mouse non-T and T cells following immunization with B. abortus. Surprisingly, B. abortus induced down-regulation of CD28 and up-regulation of B7.2 on murine CD4(+) and CD8(+) T cells. These effects on T cells were maximal for CD28 and B7.2 at 40 to 48 h and were not dependent on interleukin-12 (IL-12) or IFN-gamma. On the basis of these results, we propose that the IL-12/IFN-gamma-independent inhibition of Th2 responses to OVA/alum is secondary to the effects of B. abortus on expression of costimulatory molecules on T cells. We suggest that down-regulation of CD28 following activation inhibits subsequent differentiation of Th0 into Th2 cells. In addition, decreased expression of CD28 and increased expression of B7.2 on T cells would favor B7.2 interaction with CTLA-4 on T cells, and this could provide a negative signal to developing Th2 cells.

Vasoactive intestinal polypeptide in sacral primary sensory pathways in the cat

Unmyelinated sensory axons in the sacral spinal cord may play a role in bladder reflexes under certain pathological conditions. Previous data suggested vasoactive intestinal polypeptide (VIP) might be contained exclusively in sensory C-fibers, some of which innervate the bladder. This study was undertaken to describe the morphology of these VIP fibers in the sacral cord of the cat. VIP immunoreactivity was confined to unmyelinated axons observed at several levels of the sensory pathway including the dorsal root ganglia, dorsal roots, Lissauer's tract, and the lateral collateral pathway. A combination of light and electron microscopic observations showed VIP-immunoreactive fibers with labeled varicosities and synaptic terminals in laminae I, IIo, V, VII, and X. VIP-immunolabeled varicosities had a mean diameter of 1.6 microm (range = 0.11-7.4 microm, S.D. = 1.01, n = 311) with a small percentage (8%) being relatively large (3-7.4 microm). VIP varicosities contained a mixture of small clear vesicles (CLV) and large dense core vesicles (LDV). Although most varicosities contained a moderate number of LDVs (14.86 LDVs/microm2), some varicosities contained a large number of LDVs, whereas others contained very few. Varicosities that possessed synaptic specializations were classed as terminals and were divided into three morphological classes. Two of these resembled Gray's Type I terminal, whereas a third was similar to the Gray's Type II terminal. There was no consistent relationship between vesicle content of the terminal and the type of synaptic contact it possessed. This study shows that in the sacral spinal cord of the cat, VIP terminals originate only from C-fibers, terminate primarily in laminae I and V, and exhibit a variety of morphologies consistent with heterogeneous origins and functions of the lower urinary tract.

Obstetric history in women with surgically corrected adult urinary incontinence or pelvic organ prolapse

STUDY OBJECTIVE

To compare obstetric histories of women who had surgical correction of urinary incontinence or pelvic organ prolapse with a similar group who did not.

DESIGN

Case control study (Canadian Task Force classification II-2).

SETTING

Urban, community-based, private practice teaching hospital.

PATIENTS

Four hundred eighty women (age 51.4 +/- 13.0 yrs) who underwent corrective surgery for urinary incontinence, pelvic organ prolapse, or both, and whose obstetric history was obtainable through chart review. The control group was composed of 150 women (age 50.7 +/- 9.6 yrs) having routine screening mammography who completed a questionnaire regarding obstetric, gynecologic, and urologic history.

MEASUREMENTS AND MAIN RESULTS

Patients and controls did not differ significantly in terms of age, race, height, weight, body mass index, or smoking history. Women who underwent surgery were of greater parity (2.5 +/- 1.2 vs 2.0 +/- 1.2, p <0.001), less often nulliparous (3% vs 18%, p <0.001), less likely to have had a cesarean delivery (4% vs 15%, p <0.001), and more likely to have had a vaginal delivery (94% vs 77%, p <0.001) than those with no surgery. The odds ratio of patients who had a vaginal delivery compared with controls was 4.7 (2.3-8.3), and that for cesarean delivery was 0.22 (0.11-0.43). Analysis of specific delivery information found that, compared with controls, patients were older by 4 years at time of their first delivery (28.9 +/- 4.9 vs 24.9 +/- 4.9 yrs, p <0.001) and more commonly received epidural analgesia intrapartum (87% vs 40%, p = 0.004). Comparisons within the patient group, categorized by indication for surgery, revealed that women who had surgery for either prolapse alone or for both prolapse and incontinence were most likely to have had vaginal deliveries (85% incontinence alone vs 94% prolapse alone vs 97% both, p <0.001).

CONCLUSION

Increased parity, vaginal childbirth, maternal age at time of delivery, and use of epidural analgesia are associated with need for operative correction of pelvic organ prolapse or adult urinary incontinence. Conversely, cesarean delivery is associated with less need for surgical correction of incontinence or pelvic organ prolapse.

HIV peptide conjugated to heat-killed bacteria promotes antiviral responses in immunodeficient mice

Enhancement of immunity in the setting of HIV infection is difficult owing to loss of functional CD4+ T cells. The MHC class II-deficient mouse (II-/-) environment simulates that of the immunocompromised HIV-infected individual, since these mice have low CD4+ T cell numbers, defective CD4-dependent responses, and are susceptible to opportunistic infection. This strain was used to test whether heat-killed Brucella abortus (BA), covalently conjugated to the V3 peptide of HIV-1 (MN), could elicit anti-HIV responses. V3-BA, but not the T-dependent antigen V3-KLH, induced high levels of IL-12, IFN-gamma, and IL-10 mRNA in both wild-type (WT) and II-/- mice within 24 hr of injection. V3-BA-treated, but not V3-KLH-treated, II-/- mice developed serum IgG and IgA anti-V3 antibodies, with IgG2b and IgG3 as the predominant isotype. Viral neutralization studies, using a syncytium inhibition assay, demonstrated that the antibodies generated by V3-BA in II-/- mice were capable of neutralizing HIV. These experiments demonstrate that a heat-inactivated bacterium such as BA, when used as a carrier, can generate a cytokine environment that results in the production of neutralizing antiviral antibodies in an immunodeficient host. Such strategies could be important in the development of immunotherapies and vaccines for HIV-1 patients.

An intervention for changing high-risk HIV behaviors of African American drug-dependent women

The purpose of this study was to test the effectiveness of an AIDS education intervention for methadone-dependent, African American women. The women were randomly assigned to experimental (n=107) or control (n=97) group. The experimental group participated in a peer counseling and leadership training program conducted by two experienced nurse counselors over an 8-week period, followed by 8 weeks of reinforcement. The program was designed to reduce AIDS high-risk sexual behavior, increase self-esteem, decrease depressive affect, and increase the women's community-based AIDS prevention communication activities. A total of 130 women completed all phases of the study, including longitudinal Posttests at 2, 4, and 7 months after enrollment. Compared to the control group, there were statistically significant differences in three of the outcomes for the experimental group: The experimental group reported an increased number of safer sexual behaviors (p=.029), showed decreases in depression (p=.001), and reported engaging in more AIDS-related, community-based communication activities regarding prevention (p=.005).

Post-traumatic regeneration, neurogenesis and neuronal migration in the adult mammalian brain

Unlike the peripheral nervous system (PNS), the mammalian central nervous system (CNS) clearly lacks the robust regenerative characteristics and capacity of the former. Despite this fact, two unique regions of the adult mammalian CNS possess such regenerative potential and are capable of active regeneration following injury or structural compromise. These unique areas are the olfactory system and the neurohypophyseal system of the endocrine hypothalamus. Furthermore, it has been clearly demonstrated that primordial neuroblasts regarded as stem cells emerge from the subependymal parenchyma of the walls and floor of the third cerebral ventricle, migrate to the ventricular surface and undergo compensatory synaptogenesis within one week following hypophysectomy. In situ hybridization studies have unequivocally demonstrated that the up-regulation of nitric oxide synthase (NOS) is essential for neural (axonal) regeneration and neuronal (stem cell) migration to occur. Moreover, neuronal migration is reliably inhibited following the administration of the NO antagonist, nitroarginine. The current investigation serves to confirm a remarkable degree of plasticity and regeneration in the adult mammalian neurohypophyseal system coupled with the emergence of primordial neuroblasts that undergo apparent differentiation, migration and compensatory synaptogenesis in response to the up-regulation of NO that occurs following the trauma of hypophysectomy. Evidence from the current investigation appears to confirm that specialized glia of the neurohypophyseal system, the so-called pituicyte, proliferate following hypophysectomy and may serve as a growth matrix or structural template that may target and direct regenerating Supraoptic (SON) and Paraventricular (PVN) axons toward endothelial primordia in the regenerating neural stem and lobe.

Therapeutic potential of phosphodiesterase type 4 inhibition in chronic autoimmune demyelinating disease

It was recently demonstrated that selective phosphodiesterase type 4 (PDE4) inhibition suppresses the clinical manifestations of acute experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS), and inhibits the production of tumor necrosis factor-alpha (TNF-alpha), a pathogenetically central cytokine. Since the most common presentation of MS in humans is a relapsing-remitting course, we investigated the therapeutic potential of PDE4 inhibition in the relapsing-remitting EAE model of the SJL mouse. Administration of rolipram, the prototypic PDE4 inhibitor, reduced the clinical signs of EAE during both the initial episode of disease and subsequent relapses. In parallel, there was marked reduction of demyelination and also less inflammation throughout the central nervous system (CNS) of rolipram-treated animals. Gene expression of proinflammatory cytokines in the CNS was reduced in most of the rolipram-treated animals. Additional experiments demonstrated that PDE4 inhibition acted principally by inhibiting the secretion of Th1 cytokines, however, the encephalitogenic potential of myelin basic protein-specific T cells was not impaired. Our findings suggest that PDE4 inhibitors are a promising cytokine-directed therapy in chronic demyelinating disease.

Inhibition of primary and recall allergen-specific T helper cell type 2-mediated responses by a T helper cell type 1 stimulus

Allergic responses are characterized by the production of Ag-specific IgE Abs that are dependent upon Th2-mediated T cell help. We determined whether heat-killed Brucella abortus (BA), an inducer of Th1 responses, could influence the allergic Th2-mediated IgE response to OVA adsorbed to alum (O/A). BA plus O/A, but not O/A alone, induced high levels of mRNA for IFN-gamma and IL-12 promptly after injection. Furthermore, initial treatment with BA plus O/A rendered both BALB/c and C57Bl/6 mice incapable of mounting high IgE responses even after repeated challenges with allergen alone. Long term abrogation of anti-OVA IgE correlated with an increased frequency of IFN-gamma-secreting OVA-specific cells and a decreased frequency of IL-4-secreting OVA-specific cells. Initial treatment with anti-IL-12 prevented BA-induced early IFN-gamma production and secondary IgG2a responses, but did not abrogate IgE suppression. Additionally, secondary OVA-specific IgE responses were down-regulated by BA conjugated to OVA or by BA given with O/A. BA-induced down-regulation of secondary IgE responses was associated with increased frequency of Ag-specific IFN-gamma-secreting cells. These results suggest the possibility that even recall Th2-mediated immune responses can be attenuated if Ag is given with a carrier or adjuvant that induces potent Th1-promoting cytokines.

Inhibition of primary and recall allergen-specific T helper cell type 2-mediated responses by a T helper cell type 1 stimulus

Allergic responses are characterized by the production of Ag-specific IgE Abs that are dependent upon Th2-mediated T cell help. We determined whether heat-killed Brucella abortus (BA), an inducer of Th1 responses, could influence the allergic Th2-mediated IgE response to OVA adsorbed to alum (O/A). BA plus O/A, but not O/A alone, induced high levels of mRNA for IFN-gamma and IL-12 promptly after injection. Furthermore, initial treatment with BA plus O/A rendered both BALB/c and C57Bl/6 mice incapable of mounting high IgE responses even after repeated challenges with allergen alone. Long term abrogation of anti-OVA IgE correlated with an increased frequency of IFN-gamma-secreting OVA-specific cells and a decreased frequency of IL-4-secreting OVA-specific cells. Initial treatment with anti-IL-12 prevented BA-induced early IFN-gamma production and secondary IgG2a responses, but did not abrogate IgE suppression. Additionally, secondary OVA-specific IgE responses were down-regulated by BA conjugated to OVA or by BA given with O/A. BA-induced down-regulation of secondary IgE responses was associated with increased frequency of Ag-specific IFN-gamma-secreting cells. These results suggest the possibility that even recall Th2-mediated immune responses can be attenuated if Ag is given with a carrier or adjuvant that induces potent Th1-promoting cytokines.

Perceptions of Species Abundance, Distribution, and Diversity:Lessons from Four Decades of Sampling on a Government-Managed Reserve

/ We examined data relative to species abundance, distribution, anddiversity patterns of reptiles and amphibians to determine how perceptionschange over time and with level of sampling effort. Location data werecompiled on more than one million individual captures or observations of 98species during a 44-year study period on the US Department of Energy's(DOE) Savannah River Site National Environmental Research Park (SRS-NERP) inSouth Carolina. We suggest that perceptions of herpetofaunal speciesdiversity are strongly dependent on level of effort and that land managementdecisions based on short-term data bases for some faunal groups could resultin serious errors in environmental management. We provide evidence thatacquiring information on biodiversity distribution patterns is compatiblewith multiyear spatially extensive research programs and also provide aperspective of what might be achieved if long-term, coordinated researchefforts were instituted nationwide.To conduct biotic surveys on government-managed lands, we recommend revisionsin the methods used by government agencies to acquire and report biodiversitydata. We suggest that government and industry employees engaged inbiodiversity survey efforts develop proficiency in field identification forone or more major taxonomic groups and be encouraged to measure the status ofpopulations quantitatively with consistent and reliable methodologies. Wealso suggest that widespread academic cooperation in the dissemination ofinformation on regional patterns of biodiversity could result byestablishment of a peer-reviewed, scientifically rigorous journal concernedwith status and trends of the biota of the United States. KEY WORDS: Abundance; Amphibian; Biodiversity; Distribution; Landmanagement; Reptile

Courtship behavior and plasma levels of androgens and corticosterone in male marbled salamanders, Ambystoma opacum (ambystomatidae)

We measured plasma levels of testosterone, dihydrotestosterone (DHT), and corticosterone for male marbled salamanders (Ambystoma opacum) collected during the breeding season. Our goal was to ascertain whether steroid levels changed in response to particular reproductive behaviors or laboratory confinement. Six groups of salamanders were examined: (a) MIGRATING, males migrating toward the pond basin during the breeding season; (b) LABORATORY, males kept under confined conditions in the laboratory for 10 days; (c) LAB-FIELD, laboratory males that were later released into seminatural enclosures in the field; (d) COURTING, males from male-female pairs in which the male actively courted the female (and deposited at least one spermatophore); (e) SOLO, males that were individually isolated from conspecifics; and (f) MALE-MALE, males that were placed together in pairs, and in which one male actively courted the other male. In three groups (COURTING, SOLO, and MALE-MALE), salamanders were placed in containers for observation and each male was observed for at least 2 hr prior to a plasma sample being taken. Circulating levels of testosterone, DHT, and corticosterone did not differ significantly for males in these groups. The similarity of androgen levels among the three groups indicated a lack of behaviorally evoked change under experimental conditions designed to reveal a behavior-androgen response. Male A. opacum differ taxonomically from other amphibians showing a behavior-androgen response (three species of toads in the genus Bufo) and also lack amplexus and male-male combat during competition for mates. The effects of confinement were indicated by levels of testosterone and DHT in LABORATORY males that were significantly lower than average levels of males in the following groups: MIGRATING, LAB-FIELD, and MALE-MALE. We inferred that LAB-FIELD males, following their release to seminatural enclosures, were able to regain plasma androgen levels typical of migrating males. This increase is one of very few demonstrations for amphibians of an increase in androgen levels upon release from laboratory confinement. Levels of corticosterone did not differ significantly between males that were active in the field and males that were kept in the laboratory. The similarity of corticosterone levels among these groups differs from the typical pattern of elevated corticosterone and depressed androgen levels in captive amphibians. Maximal corticosterone levels in breeding male A. opacum may act differently than in other species in which chronic elevations inhibit the pituitary-gonadal axis.

AIDS prevention in high-risk African American women: behavioral, psychological, and gender issues

A three-year longitudinal intervention study was implemented to reduce high-risk drug and sexual behaviors in methadone-dependent African American women. Participants were recruited from four inner-city methadone maintenance programs and randomly assigned either to an eight-week peer counseling and leadership training group or to a control group. The 107 trainees and 97 controls completed pretests and posttests at two, four, and seven months. This paper focuses on final data related to the subjects' sexual beliefs, attitudes, knowledge, and behaviors that put them at risk for HIV/AIDS. Reasons for not using condoms are categorized and discussed. Despite the women's awareness of the seriousness of AIDS, perceived powerlessness to negotiate condom use, negative attitudes about the use of condoms, influence of drugs, and unavailablility of condoms interfered with safer sex practices. The inability of education alone to prevent many high-risk sexual behaviors suggests that more serious consideration be given to expanded distribution of condoms as well as needle exchange programs and legalization of illicit drugs.

Distinct roles for B7-1 (CD-80) and B7-2 (CD-86) in the initiation of experimental allergic encephalomyelitis

The activation and differentiation of T cells require both antigen/MHC recognition and costimulatory signals. The present studies examined the role of B7-1 (CD80) and B7-2 (CD86) costimulation in the prototypic autoimmune disorder, experimental allergic encephalomyelitis (EAE). In adoptively transferred EAE, in vitro activation of myelin basic protein (MBP)-specific lymph node cells was inhibited by the combination of anti-CD80 plus anti-CD86, but not individually. However, in actively induced disease, one injection of anti-CD80 significantly reduced disease, while anti-CD86 exacerbated disease. Interestingly, one injection of CTLA-4Ig suppressed disease, while multiple injections resulted in enhanced disease. Thus, the costimulation provided by B7-1 molecules appears to be important for the development of encephalitogenic T cells. The enhanced disease caused by multiple injections of CTLA-4Ig or a single injection of anti-CD86 suggests an inhibitory function for CD86 interaction with its counterreceptors CD28 and CTLA-4 in EAE. Alternatively, these results are consistent with an essential timing requirement for the coordinated interaction of B7 and CD28 family receptors, and that disruption of this critical timing can have opposing results on the outcome of an immune response.

Vaccine strategies: targeting helper T cell responses

Vaccine strategies need to take into account the balance of T helper subsets they induce. TH1 cells, which secrete IFN gamma and IL-2, are associated with CMI, rather than humoral responses, and afford protection against intracellular infections including parasites. In contrast, TH2 cells secrete IL-4, IL-5, and IL-10; elicit high-titer antibody responses and poor CMI; and are associated with susceptibility to infection with intracellular pathogens. Depending on the type of TH cell bias required, it is possible to manipulate the immune response to a protein or peptide by employing (1) different adjuvants, (2) conjugating the protein to various carriers, (3) immunizing in the presence of cytokines, (4) using alternative routes of administration, or (5) using different forms or doses of antigen. To apply these approaches to a particular vaccine, it is necessary to identify which component of the infectious agent (e.g., envelope protein or peptide) or allergen to target. Once the type of TH cell response that is protective is identified, it may be possible to combine a protein with an adjuvant or link it to a carrier that will promote responses towards the most advantageous TH subset.

Neural regeneration and neuronal migration following injury. I. The endocrine hypothalamus and neurohypophyseal system

Central to this investigation are several basic hypotheses that are designed to test the role of nitric oxide (NO) in the complex process of central regeneration and plasticity in a well established model system of the mammalian brain. We have employed histochemical techniques at the light and ultrastructural level coupled with correlative scanning electron microscopy, immunoelectron microscopy, and in situ hybridization in order to determine the functional significance of the increased expression of nitric oxide synthase (NOS) in neurons of the supraoptic (SON) and paraventricular (PVN) nuclei which accompanies regeneration of their axotomized neurites following hypophysectomy. The aim of this investigation was to determine the potential role and temporal up-regulation of NOS in this basic regenerative process and to establish the ultrastructural and neuroanatomical correlates during critical periods of regeneration and regrowth of SON and PVN axons following hypophysectomy in the endocrine hypothalamus of the rat. Our data support the hypothesis that NO may serve as a second messenger molecule that may act in some fashion to govern not only the process of central regeneration and regrowth of magnocellular (SON/PVN) axons into the median eminence, neural stem, and neural lobe (the neurohypophyseal system) but may also influence the regeneration of neurites into new neuroanatomical domains such as the adjacent lumen of the third cerebral ventricle. We have demonstrated a distinct temporal relationship between injury (axotomy) of SON/PVN axons and the establishment of new neurovascular zones following hypophysectomy with the up-regulation of NOS. This up-regulation appears to correlate well with successful regeneration in the mammalian neurohypophyseal system. We have also successfully inhibited axonal regeneration with the use of nitroarginine, a competitive antagonist of NO. NOS up-regulation attendant to regeneration of SON and PVN axons may have inestimable clinical implications, particularly with respect to closed head injury and cerebral contusion that involves the mechanical shearing of the infundibular stalk. In addition, this investigation has reaffirmed that large numbers of bona fide neurons migrate and emerge upon the floor of the adjacent third cerebral ventricle shortly following hypophysectomy (within 2 weeks). The origin and mechanisms of neuronal migration and plasticity following hypophysectomy are the subject of interpretation and discussion in this investigation.

Retinoid treatment of experimental allergic encephalomyelitis. IL-4 production correlates with improved disease course

Experimental allergic encephalomyelitis (EAE) is an autoimmune disease characterized by central nervous system inflammation and demyelination. Retinoids regulate cell differentiation and growth by binding to and activating retinoic acid receptors, which seem to be nuclear transcription factors. The effect of retinoids on chronic relapsing EAE produced by the transfer of myelin basic protein (MBP)-specific lymph node cells (LNC) was studied. All-trans-retinoic acid (tRA) inhibited the proliferation of MBP-specific LNC in vitro. However, the capacity of these cells to transfer EAE was markedly reduced by concentrations of tRA that only mildly inhibited T cell proliferation. The presence of tRA during in vitro MBP-specific LNC activation resulted in a considerable increase in IL-4 mRNA, whereas mRNA for IL-2, TNF-alpha, and IFN-gamma was decreased. Increased IL-4 also was detected in culture supernatants. However, the presence of a neutralizing Ab to IL-4 (11B11) during MBP-specific LNC activation in vitro did not reverse the inhibition of encephalitogenicity caused by tRA. The administration of retinoids in vivo resulted in an improved clinical course, even when given after disease onset. These findings suggest that T cell activation in the presence of tRA results in the development of T cells of the Th2 phenotype, which, in turn, might be responsible for the decrease in the encephalitogenicity of MBP-specific T cells. The modulation by retinoids of an immune response dominated by Th1-like T cells to one in which the protective cytokines of Th2-like cells predominate may have potential relevance for human demyelinating diseases such as multiple sclerosis.

Case management of HIV-infected children in Missouri

The early referral of HIV-exposed children and their mothers to coordinated medical and social services has become increasingly important. In July 1989, the Missouri Department of Health initiated the Service Coordination Program to provide individualized referral (case management) for Missouri residents who were reported to have acquired immunodeficiency syndrome (AIDS) or HIV infection. The purpose of the Service Coordination Program is to assist persons in accessing medical and social services. The authors describe the characteristics of the 36 children (18 enrolled in the Service Coordination Program, and 18 not enrolled) reported to the Missouri Department of Health through September 1992. Although more detailed evaluations are necessary, preliminary data suggest that opportunities for early intervention may be facilitated by the Service Coordination Program if the child's HIV status is recognized early.

Retinoid treatment of experimental allergic encephalomyelitis. IL-4 production correlates with improved disease course

Experimental allergic encephalomyelitis (EAE) is an autoimmune disease characterized by central nervous system inflammation and demyelination. Retinoids regulate cell differentiation and growth by binding to and activating retinoic acid receptors, which seem to be nuclear transcription factors. The effect of retinoids on chronic relapsing EAE produced by the transfer of myelin basic protein (MBP)-specific lymph node cells (LNC) was studied. All-trans-retinoic acid (tRA) inhibited the proliferation of MBP-specific LNC in vitro. However, the capacity of these cells to transfer EAE was markedly reduced by concentrations of tRA that only mildly inhibited T cell proliferation. The presence of tRA during in vitro MBP-specific LNC activation resulted in a considerable increase in IL-4 mRNA, whereas mRNA for IL-2, TNF-alpha, and IFN-gamma was decreased. Increased IL-4 also was detected in culture supernatants. However, the presence of a neutralizing Ab to IL-4 (11B11) during MBP-specific LNC activation in vitro did not reverse the inhibition of encephalitogenicity caused by tRA. The administration of retinoids in vivo resulted in an improved clinical course, even when given after disease onset. These findings suggest that T cell activation in the presence of tRA results in the development of T cells of the Th2 phenotype, which, in turn, might be responsible for the decrease in the encephalitogenicity of MBP-specific T cells. The modulation by retinoids of an immune response dominated by Th1-like T cells to one in which the protective cytokines of Th2-like cells predominate may have potential relevance for human demyelinating diseases such as multiple sclerosis.

Cytokine-induced immune deviation as a therapy for inflammatory autoimmune disease

The properties and outcome of an immune response are best predicted by the lymphokine phenotype of the responding T cells. Cytokines produced by CD4+ T helper type 1 (Th1) T cells mediate delayed type hypersensitivity (DTH) and inflammatory responses, whereas cytokines produced by Th2 T cells mediate helper T cell functions for antibody production. To determine whether induction of Th2-like cells would modulate an inflammatory response, interleukin 4 (IL-4) was administered to animals with experimental allergic encephalomyelitis (EAE), a prototypic autoimmune disease produced by Th1-like T cells specific for myelin basic protein (MBP). IL-4 treatment resulted in amelioration of clinical disease, the induction of MBP-specific Th2 cells, diminished demyelination, and inhibition of the synthesis of inflammatory cytokines in the central nervous system (CNS). Modulation of an immune response from one dominated by excessive activity of Th1-like T cells to one dominated by the protective cytokines produced by Th2-like T cells may have applicability to the therapy of certain human autoimmune diseases.

Superantigen modulation of experimental allergic encephalomyelitis: activation of anergy determines outcome

Experimental allergic encephalomyelitis (EAE) is an autoimmune disease that can be induced by the adoptive transfer of CD4, myelin basic protein (MBP)-specific T cells. Superantigens activate T cells expressing appropriate TCR V genes. In this study, MBP-specific T cells activated in vitro with a superantigen, staphylococcal enterotoxin B (SEB), could adoptively transfer a severe form of EAE in (PLxSJL)F1 mice, but did not transfer disease in PL/J or SJL/J mice. SEB treatment of donor mice anergized MBP-specific T cells using V beta 8 in (PLxSJL)F1 mice, because subsequent in vitro activation with SEB resulted in a marked decrease in proliferation to SEB and inability to transfer EAE. However, donor cells from (PLxSJL)F1 mice immunized with MBP/CFA that had been exposed to SEB in vivo before MBP stimulation in vitro still produced EAE in recipient mice. To confirm that non-V beta 8 T cells could transfer disease, donor mice were treated with antibody that eliminated V beta 8 T cells; MBP-activated T cells from these mice could still transfer EAE. Finally, EAE induced by SEB-activated T cells was substantially reduced in mice receiving anti-V beta 8 therapy in vivo. The ability of superantigens to activate encephalitogenic T cells may have relevance to human diseases such as multiple sclerosis.

Superantigen modulation of experimental allergic encephalomyelitis: activation of anergy determines outcome

Experimental allergic encephalomyelitis (EAE) is an autoimmune disease that can be induced by the adoptive transfer of CD4, myelin basic protein (MBP)-specific T cells. Superantigens activate T cells expressing appropriate TCR V genes. In this study, MBP-specific T cells activated in vitro with a superantigen, staphylococcal enterotoxin B (SEB), could adoptively transfer a severe form of EAE in (PLxSJL)F1 mice, but did not transfer disease in PL/J or SJL/J mice. SEB treatment of donor mice anergized MBP-specific T cells using V beta 8 in (PLxSJL)F1 mice, because subsequent in vitro activation with SEB resulted in a marked decrease in proliferation to SEB and inability to transfer EAE. However, donor cells from (PLxSJL)F1 mice immunized with MBP/CFA that had been exposed to SEB in vivo before MBP stimulation in vitro still produced EAE in recipient mice. To confirm that non-V beta 8 T cells could transfer disease, donor mice were treated with antibody that eliminated V beta 8 T cells; MBP-activated T cells from these mice could still transfer EAE. Finally, EAE induced by SEB-activated T cells was substantially reduced in mice receiving anti-V beta 8 therapy in vivo. The ability of superantigens to activate encephalitogenic T cells may have relevance to human diseases such as multiple sclerosis.

In situ fixation of the neonatal brain and spinal cord

A delay in the autopsy can result in significant tissue autolysis, especially in the central nervous system. We have developed a rapid technique of in situ fixation that preserves central nervous system tissues until the formal autopsy can be performed. Through the lateral margin of the anterior fontanelle, Zamboni's solution is injected percutaneously into the lateral ventricles and allowed to exit via an intrathecal spinal needle. The choice of fixative allows a wide array of postmortem studies to be done.

Transplantation of the mammalian pineal gland: studies of survival, revascularization, reinnervation, and recovery of function

The survival, revascularization, reinnervation, and recovery of function of transplanted rat pineal glands were studied following grafting into four different locations in pinealectomized rats. Pineal grafts were well vascularized by fenestrated capillaries. Pinealocytes in the grafts maintained high-metabolic activity. More nerve fibers and terminals were observed in the grafts within the anterior chamber of the eye than in the third cerebral ventricle and the pineal region (in situ transplantation). No fibers or terminals were found in grafts placed beneath the renal capsule. Nighttime serum melatonin levels increased significantly in pinealectomized rats with transplants into either the third cerebral ventricle or the anterior eye chamber. This increase might reflect graft reinnervation. Yet day-night differences in serum melatonin were observed only in host rats receiving transplants in the anterior eye chamber. In conclusion, pinealocytes survived transplantation into different locations and exhibited ultrastructural features indicative of active secretory processes; however, day-night differences in serum melatonin are only restored following transplants into the anterior eye chamber. Reinnervation of the grafts by the host superior cervical ganglion is necessary for this restoration.

Increased expression of nitric oxide synthase in hypothalamic neuronal regeneration

This investigation deals with the histochemical and scanning electron microscopic (SEM) correlates that depict regeneration of the neurohypophyseal system that may be nitric oxide dependent following hypophysectomy in the rodent hypothalamus. NOS histochemistry and correlative SEM were employed to establish the rates of regrowth and appearance of NOS-positive supraoptic (SON) and paraventricular (PVN) neurites and their cell bodies following hypophysectomy. NOS activity increased significantly in SON and PVN neuronal perikarya and regenerating axons by 2 weeks. NOS-positive neurites were observed to regrow into the adjacent median eminence and insinuate into the lumen of the third cerebral ventricle. By 4 weeks posthypophysectomy, NOS staining of SON and PVN neurons and their regrown neurites had returned to normal control levels. Despite this fact, large complexes of apparent magnocellular neurites remained upon the floor of the third cerebral ventricle as observed with SEM. These observations support the hypothesis that NO may play a fundamental role in the process of regeneration, plasticity, and retargeting of SON and PVN axons following injury.

Studies of T cell deletion and T cell anergy following in vivo administration of SEB to normal and lupus-prone mice

This study examines the responses of lupus-prone NZB, (NZB x NZW) F1, BXSB, MRL-lpr/lpr and control mice (H-2 and Mls matched) to in vivo administration of the superantigen staphylococcal enterotoxin B (SEB). Two weeks after i.v. administration of 500 micrograms SEB, CD4+V beta 8+ lymph node T cells were deleted equivalently by lupus-prone and control mice. However, IE+ strains deleted a greater proportion (47% to 77%) of their CD4+V beta 8+ cells than did IE- strains (24% to 27%). CD8+V beta 8+ cells were deleted less than CD4+V beta 8+ cells by injection of 500 micrograms SEB. IE- strains failed to delete CD8+V beta 8+ cells, whereas six of seven IE+ strains deleted > 25% of their CD8+V beta 8+ cells. IE+ MRL-lpr/lpr mice showed some impairment in deletion: they failed to delete CD8+V beta 8+ cells at all doses of SEB and had reduced deletion of CD4+V beta 8+ cells at low doses of in vivo SEB (10 and 50 micrograms). Peripheral expansion of the intrathymically deleted V beta 7 TCR family was not observed in lupus-prone mice 2 wk after 500 micrograms in vivo SEB. In vitro restimulation with SEB of mice previously injected with 500 micrograms SEB demonstrated anergy in T cells from all strains, including the IE- and MRL-lpr/lpr. This result contrasts with previous reports of tolerance defects in lupus-prone strains using B cell read-out assays as measures of tolerance. The present study demonstrates that there is no global defect in peripheral T cell deletion or anergy in lupus-prone mice to the superantigen SEB. Although additional Ag would need to be studied, these experiments raise the possibility that some reported tolerance defects in lupus-prone strains may reflect excessive B cell responses to relatively normal T cell signals.

Studies of T cell deletion and T cell anergy following in vivo administration of SEB to normal and lupus-prone mice

This study examines the responses of lupus-prone NZB, (NZB x NZW) F1, BXSB, MRL-lpr/lpr and control mice (H-2 and Mls matched) to in vivo administration of the superantigen staphylococcal enterotoxin B (SEB). Two weeks after i.v. administration of 500 micrograms SEB, CD4+V beta 8+ lymph node T cells were deleted equivalently by lupus-prone and control mice. However, IE+ strains deleted a greater proportion (47% to 77%) of their CD4+V beta 8+ cells than did IE- strains (24% to 27%). CD8+V beta 8+ cells were deleted less than CD4+V beta 8+ cells by injection of 500 micrograms SEB. IE- strains failed to delete CD8+V beta 8+ cells, whereas six of seven IE+ strains deleted &gt; 25% of their CD8+V beta 8+ cells. IE+ MRL-lpr/lpr mice showed some impairment in deletion: they failed to delete CD8+V beta 8+ cells at all doses of SEB and had reduced deletion of CD4+V beta 8+ cells at low doses of in vivo SEB (10 and 50 micrograms). Peripheral expansion of the intrathymically deleted V beta 7 TCR family was not observed in lupus-prone mice 2 wk after 500 micrograms in vivo SEB. In vitro restimulation with SEB of mice previously injected with 500 micrograms SEB demonstrated anergy in T cells from all strains, including the IE- and MRL-lpr/lpr. This result contrasts with previous reports of tolerance defects in lupus-prone strains using B cell read-out assays as measures of tolerance. The present study demonstrates that there is no global defect in peripheral T cell deletion or anergy in lupus-prone mice to the superantigen SEB. Although additional Ag would need to be studied, these experiments raise the possibility that some reported tolerance defects in lupus-prone strains may reflect excessive B cell responses to relatively normal T cell signals.

Collaboration as a strategy for acquired immunodeficiency syndrome prevention

An eight-session training model used a social interactive framework to combine theoretical and methodological aspects of peer counseling, cross-cultural communication, and transcultural nursing, with a conviction that the participants (volunteers from an ongoing, urban methadone maintenance program) had significant strengths on which to build. The objective was to assist urban, drug dependent black women in taking control of their own lives through collaboration with health care professionals to develop and promote culturally acceptable behavioral alternatives related to reduction of risk for human immunodeficiency virus. The collaborative approach focused on rewards of behavioral change and minimized attention to prevention of negative behaviors, while openly valuing input from the women who are potential health promoters in their own communities. Evaluation of the Peer Counseling Leadership Training Program suggested that the approach facilitated personal risk-reducing behavioral change, improved self esteem, and successfully promoted involvement in community-based prevention efforts.

Studies of bone marrow progenitor cells in lupus-prone mice. I. NZB marrow cells demonstrate increased growth in Whitlock-Witte culture and increased splenic colony-forming unit activity in the Thy-1-, lineage- population

Previous studies have demonstrated that NZB marrow can transfer features of autoimmunity. Therefore, we undertook a study of NZB marrow to determine whether it demonstrated any phenotypic abnormalities. In Whitlock-Witte cultures, NZB marrow cells generated nonadherent cells at low seeding densities, densities at which marrow from other strains did not generate nonadherent cells. In contrast, NZB marrow grew less well than controls in Dexter cultures. Inasmuch as the latter favor growth of granulocyte-macrophage precursors and the former B cells, these results suggest a possible skewing of NZB marrow cells toward lymphocyte production. Unfractionated marrow cells from NZB mice were found to produce 10-fold more splenic colonies in lethally irradiated recipients than marrow cells from control mice. This result was independent of the genotype of the recipient. When the progenitor Thy-1lo, Lin- marrow subpopulation was studied, NZB mice did not differ substantially from controls regarding splenic CFU. Therefore, Thy-1-, Lin- marrow cells were studied as a possible source of the excess splenic CFU in NZB mice. Indeed, the NZB Thy-1-, Lin- population contained 30-fold more splenic CFU than did the Thy-1-, Lin- population from control mice. These results suggest that NZB mice have unusual marrow progenitor cells; such cells may play a role in their autoimmune disease.

Studies of bone marrow progenitor cells in lupus-prone mice. I. NZB marrow cells demonstrate increased growth in Whitlock-Witte culture and increased splenic colony-forming unit activity in the Thy-1-, lineage- population

Previous studies have demonstrated that NZB marrow can transfer features of autoimmunity. Therefore, we undertook a study of NZB marrow to determine whether it demonstrated any phenotypic abnormalities. In Whitlock-Witte cultures, NZB marrow cells generated nonadherent cells at low seeding densities, densities at which marrow from other strains did not generate nonadherent cells. In contrast, NZB marrow grew less well than controls in Dexter cultures. Inasmuch as the latter favor growth of granulocyte-macrophage precursors and the former B cells, these results suggest a possible skewing of NZB marrow cells toward lymphocyte production. Unfractionated marrow cells from NZB mice were found to produce 10-fold more splenic colonies in lethally irradiated recipients than marrow cells from control mice. This result was independent of the genotype of the recipient. When the progenitor Thy-1lo, Lin- marrow subpopulation was studied, NZB mice did not differ substantially from controls regarding splenic CFU. Therefore, Thy-1-, Lin- marrow cells were studied as a possible source of the excess splenic CFU in NZB mice. Indeed, the NZB Thy-1-, Lin- population contained 30-fold more splenic CFU than did the Thy-1-, Lin- population from control mice. These results suggest that NZB mice have unusual marrow progenitor cells; such cells may play a role in their autoimmune disease.

Strategies for AIDS prevention: leadership training and peer counseling for high-risk African-American women in the drug user community

A culturally congruent training program to promote HIV risk-reduction behaviors was implemented in a convenient sample of 9 African-American women in an urban methadone treatment program. At each of eight peer counseling and leadership training (PCLT) program sessions, the transmission and prevention of AIDS were discussed while emphasizing enhancement of participants' self-esteem, confidence, and control over high-risk behaviors. The results indicate that support of the women helped develop their sense of purpose and self-worth, reduced sexual and drug use practices associated with risk for HIV and AIDS infection, and promoted assumption of leadership roles and dissemination of accurate AIDS-related information in their communities. It was apparent that knowledge alone does not change behavior if it conflicts with established norms, values, beliefs, and life-styles and that individuals who have a sense of personal control are more willing to explore alternative lower-risk behaviors.

Cytokine gene expression after in vivo primary immunization with goat antibody to mouse IgD antibody

Cytokines are important mediators of effector lymphoid cell function during an immune response, but their expression during an in vivo immune response has not been well documented. We analyzed the kinetics of cytokine gene expression during the course of an in vivo primary immune response to goat antibody to mouse IgD antibody. Total RNA was purified from spleens taken from freshly killed BALB/c mice 1 to 7 days after immunization. The reverse transcriptase polymerase chain reaction was used to evaluate the expression of seven cytokine genes, all of which encode cytokines that are secreted by T cells and are important in T and/or B cell activation and differentiation. These were IFN-gamma, IL-2, IL-4, IL-5, IL-6, IL-9, and IL-10. IL-2 and IL-9 exhibited an early elevated expression at days 2 to 3, and declined as the expression of IL-4, IL-6, IL-10, and IFN-gamma increased. In contrast, IL-5 gene expression showed little change, exhibiting a similar pattern to the housekeeping gene, hypoxanthine-guanine phosphoribosyl transferase. Cell sorting of CD4+ and CD4- cells at day 3 and day 5 after immunization revealed that CD4+ cells were the predominant source of the elevated cytokines (with the exception of IL-6). Our results demonstrate a specific and highly reproducible cytokine gene expression pattern during the course of a primary in vivo immune response that is marked by an absence of a clear-cut Th1/Th2 dichotomy.

Cytokine gene expression after in vivo primary immunization with goat antibody to mouse IgD antibody

Cytokines are important mediators of effector lymphoid cell function during an immune response, but their expression during an in vivo immune response has not been well documented. We analyzed the kinetics of cytokine gene expression during the course of an in vivo primary immune response to goat antibody to mouse IgD antibody. Total RNA was purified from spleens taken from freshly killed BALB/c mice 1 to 7 days after immunization. The reverse transcriptase polymerase chain reaction was used to evaluate the expression of seven cytokine genes, all of which encode cytokines that are secreted by T cells and are important in T and/or B cell activation and differentiation. These were IFN-gamma, IL-2, IL-4, IL-5, IL-6, IL-9, and IL-10. IL-2 and IL-9 exhibited an early elevated expression at days 2 to 3, and declined as the expression of IL-4, IL-6, IL-10, and IFN-gamma increased. In contrast, IL-5 gene expression showed little change, exhibiting a similar pattern to the housekeeping gene, hypoxanthine-guanine phosphoribosyl transferase. Cell sorting of CD4+ and CD4- cells at day 3 and day 5 after immunization revealed that CD4+ cells were the predominant source of the elevated cytokines (with the exception of IL-6). Our results demonstrate a specific and highly reproducible cytokine gene expression pattern during the course of a primary in vivo immune response that is marked by an absence of a clear-cut Th1/Th2 dichotomy.

NIH conference. Systemic lupus erythematosus

Although the cause of systemic lupus erythematosus remains unknown, pathogenic mechanisms are becoming clearer. Both genetic and environmental factors have been implicated in the induction and in the perpetuation of lupus. Implicated environmental triggers include ultraviolet light, chemicals (hydrazines, hair dyes, drugs), some foods, and possibly infectious agents. Lupus is mediated by the immune system. Patients have excess numbers of antibody-forming cells, including those that produce antibodies reactive with self-antigens. Patients also have an increased number of activated T cells, some of which help B cells to produce autoantibodies. A loss of tolerance is a critical immune abnormality in lupus; many of the activated helper T cells may result from a failure in normal tolerance mechanisms. A hematopoietic stem-cell defect could give rise to both B- and T-cell abnormalities. Such a stem-cell abnormality might lead to both a loss of self-tolerance and polyclonal B-cell activation. Antigen-driven, T-cell-dependent expansion of B-cell clones would then give rise to pathogenic autoantibodies, including anti-DNA. We believe that lupus is a syndrome: Patients differ regarding specific inciting factors and immune defects. Some patients have genetically conditioned abnormalities, similar to those found in mice with lupus; others have a combination of genetic and acquired defects. We hope that insights into pathogenesis lead to improved and more individualized therapy.

No difference in day-night serum melatonin concentration after pineal grafting into the third cerebral ventricle of pinealectomized rats

Serum melatonin concentration and its day-night difference in pinealectomized, stereotaxically grafted rats with pineal transplants was examined. The nighttime serum melatonin concentration increased significantly only in pinealectomized rats that received two pineal transplants. In neither pinealectomized rats receiving two pineal glands and one cotransplant of superior cervical sympathetic ganglion nor pinealectomized-ganglionectomized rats receiving two pineal transplants was there a demonstrable increased in serum melatonin concentration. Although some pineal transplanted hosts demonstrated increases in serum melatonin concentration, there was no day-night variation in serum melatonin concentration. This may be due to a number of mitigating factors. Pineal grafts may not receive the appropriate functional reinnervation from the host brain due to the location of the transplantation in the cerebral ventricle or due to lack of sufficient time for the growth of invading host neurites.

Anti-CD3 antibody induces rapid expression of cytokine genes in vivo

Anti-CD3 antibody was administered to mice i.v. and the kinetics of spleen cell cytokine mRNA expression studied by Northern analysis. Untreated mice and mice receiving control antibody had low or undetectable amounts of mRNA for c-fos, c-myc, IL-2, IL-4, and IFN-gamma. After injection of anti-CD3 antibody, substantial increases in all were found. Induction of c-fos was detected at 10 min and of c-myc at 30 min after injection. IL-2, IL-4, and IFN-gamma mRNA were induced by 30 min and reached peak levels at 60 min. Thereafter, IL-2 and IL-4 mRNA declined, whereas IFN-gamma mRNA persisted. The induced cytokine mRNA was not observed in athymic nu/nu mice nor in normal spleen cells from which T cells had been depleted in vitro. The early in vivo induction of IL-4 mRNA contrasts with prior in vitro studies in which IL-4 production was difficult to detect after primary stimulation. To assess the possibility that many T cells had been preprimed in vivo, germfree mice were compared with conventional mice and no differences in cytokine mRNA were found. These data show that T cell-dependent IL message production can be induced rapidly in vivo without prepriming and that the cytokine messages induced after anti-CD3 antibody administration do not suggest a predominance of either Th1 or Th2 type cells.

Anti-CD3 antibody induces rapid expression of cytokine genes in vivo

Anti-CD3 antibody was administered to mice i.v. and the kinetics of spleen cell cytokine mRNA expression studied by Northern analysis. Untreated mice and mice receiving control antibody had low or undetectable amounts of mRNA for c-fos, c-myc, IL-2, IL-4, and IFN-gamma. After injection of anti-CD3 antibody, substantial increases in all were found. Induction of c-fos was detected at 10 min and of c-myc at 30 min after injection. IL-2, IL-4, and IFN-gamma mRNA were induced by 30 min and reached peak levels at 60 min. Thereafter, IL-2 and IL-4 mRNA declined, whereas IFN-gamma mRNA persisted. The induced cytokine mRNA was not observed in athymic nu/nu mice nor in normal spleen cells from which T cells had been depleted in vitro. The early in vivo induction of IL-4 mRNA contrasts with prior in vitro studies in which IL-4 production was difficult to detect after primary stimulation. To assess the possibility that many T cells had been preprimed in vivo, germfree mice were compared with conventional mice and no differences in cytokine mRNA were found. These data show that T cell-dependent IL message production can be induced rapidly in vivo without prepriming and that the cytokine messages induced after anti-CD3 antibody administration do not suggest a predominance of either Th1 or Th2 type cells.

Transplantation of the pineal gland in the mammalian third cerebral ventricle

Fine structural correlates and functional parameters were measured in pinealectomized rats following grafting of the pineal gland into the third cerebral ventricle. Pinealectomy caused a significant decrease in serum melatonin concentration of animals compared to that in normal controls. No significant difference was observed in the serum melatonin concentration between pinealectomized rats and those receiving sham transplantation with fragments of occipital cortex. By 6 weeks nearly 50% of pinealectomized rats receiving pineal transplants demonstrated a significant increase in the serum melatonin concentration in contrast to that of pinealectomized rats and pinealectomized animals receiving sham transplants. Pinealocytes survived and flourished following transplantation from the epithalamic region to the third cerebral ventricle of the hypothalamus in host rats. These cells were found to be arranged individually or in clusters surrounding fenestrated capillaries of the graft. Moreover, these pinealocytes demonstrated ultrastructural features indicative of an active secretory process, including dense-core and clear vesicles as well as vacuoles containing flocculent material. Additional characteristics distinctive of normal control pinealocytes were observed in surviving cells of grafts, such as synaptic ribbons, synaptic ribbon fields, and myeloid bodies. Bundles of unmyelinated axons and apparent adrenergic nerve endings were observed with transmission electron microscopy and immunocystochemistry using antisera against tyrosine hydroxylase (TH). Nerve fibers and terminals were found within perivascular spaces surrounding fenestrated capillaries of viable grafts. These reported observations suggest that a significant population of transplanted pinealocytes recover functional activity (e.g., heightened melatonin secretion) following stereotaxic grafting into the third cerebral ventricles of pinealectomized animals. This apparent recovery of function may be linked directly to reinnervation of the gland by nerve fibers that appear to arise from the underlying median eminence.