A simplified cranial cavity model to understand the relationship between intracranial pressure and dural sinus pressure

Although accurate intracranial pressure (ICP) monitoring is essential for the diagnosis and treatment of severe brain diseases, current methods are performed invasively. Therefore, a safe and less invasive ICP measurement is required. The purpose of our study was to develop a simplified cranial cavity model for a better understanding of the relationship between the ICP and the pressure measurement within the dural venous sinus (DVS) to support the validity of using sinus pressure as the surrogate of the ICP. The in-house cranial cavity model had three components: the brain part, the DVS part, and the subarachnoid space (SAS) part. Pressure in other parts was measured when the pressure in the SAS part and, separately, brain part was increased from 0 (baseline) to 50 mmHg at intervals of 10 mmHg. When the pressure in the SAS part was increased from 10 to 50 mmHg at 10 mmHg interval, pressures of both the brain and DVS parts increased without significant difference (all P > 0.05). However, pressures in both the SAS and DVS parts differed while the pressure in the brain part was increased. The pressures in both parts showed about 70% of the increase in the brain part. Nevertheless, the pressures in the SAS and DVS parts were not significantly different (P > 0.05). A simplified in-house cranial cavity model was developed consisting of three compartments to represent the actual intracranial spaces. The pressure measurement within the DVS was feasible to use as a surrogate for the ICP measurement.

Kinetics of Glycoprotein-Specific Antibody Response in Patients with Severe Fever with Thrombocytopenia Syndrome

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging tickborne disease in East Asia that is causing high mortality. The Gn glycoprotein of the SFTS virus (SFTSV) has been considered to be an essential target for virus neutralization. However, data on anti-Gn glycoprotein antibody kinetics are limited. Therefore, we investigated the kinetics of Gn-specific antibodies compared to those of nucleocapsid protein (NP)-specific antibodies. A multicenter prospective study was performed in South Korea from January 2018 to September 2021. Adult patients with SFTS were enrolled. Anti-Gn-specific IgM and IgG were measured using an enzyme-linked immunosorbent assay. A total of 111 samples from 34 patients with confirmed SFTS were analyzed. Anti-Gn-specific IgM was detected at days 5–9 and peaked at day 15–19 from symptom onset, whereas the anti-NP-specific IgM titers peaked at days 5–9. Median seroconversion times of both anti-Gn- and NP-specific IgG were 7.0 days. High anti-Gn-specific IgG titers were maintained until 35–39 months after symptom onset. Only one patient lost their anti-Gn-specific antibodies at 41 days after symptom onset. Our data suggested that the anti-Gn-specific IgM titer peaked later than anti-NP-specific IgM, and that anti-Gn-specific IgG remain for at least 3 years from symptom onset.

Infrared microspectroscopy combined with conventional atomic force microscopy

This paper reports nanotopography and mid infrared (IR) microspectroscopic imaging coupled within the same atomic force microscope (AFM). The reported advances are enabled by using a bimaterial microcantilever, conventionally used for standard AFM imaging, as a detector of monochromatic IR light. IR light intensity is recorded as thermomechanical bending of the cantilever measured upon illumination with intensity-modulated, narrowband radiation. The cantilever bending is then correlated with the sample's IR absorption. Spatial resolution was characterized by imaging a USAF 1951 optical resolution target made of SU-8 photoresist. The spatial resolution of the AFM topography measurement was a few nanometers as expected, while the spatial resolution of the IR measurement was 24.4 μm using relatively coarse spectral resolution (25-125 cm(-1)). In addition to well-controlled samples demonstrating the spatial and spectral properties of the setup, we used the method to map engineered skin and three-dimensional cell culture samples. This research combines modest IR imaging capabilities with the exceptional topographical imaging of conventional AFM to provide advantages of both in a facile manner.

New HER2 Assay Using Trastuzumab for the Selection of Trastuzumab Responding Breast Cancer: The Positivity Is Significantly Associated with Pathologic Complete Response after Preoperative Chemotherapy

Background:The evaluation of HER2 status is required for trastuzumab therapy in breast cancer. Although there are a few methods for an evaluation of HER2 status, theoretically the better method would be to check trastuzumab uptake itself in the tumor after trastuzumab administration. Therefore, we developed a different HER2 test (QHerceptest) using trastuzumab to improve an accuracy in the selection of patient for trastuzumab therapy.Patients and Methods:31 patients with HER2 positive (IHC 3+: 19 and IHC 2+ with FISH positive: 12) early breast cancer who were enrolled in a phase II preoperative paclitaxel, gemcitabin and trastuzumab (PGH) combination chemotherapy trial were evaluated. The pre-chemotherapy tumor specimens were obtained from the breast mass (n=24) or metastatic lymph nodes (n=7). After completing 6 cycles of PGH therapy, all patients underwent breast conserving surgery or mastectomy. We applied trastuzumab and Quantum dot conjugated goat anti-human IgG (QD-IgG, 655nm, Invitrogen) in the process of immunuhistochemistry for HER2 using formalin-fixed paraffin embedded specimen. After antigen retrieval, trastuzuamb was applied followed by QD-IgG. The result of QHerceptest was scored as negative, weak positive, moderate positive, or strong positive, and its relative uptake (RU) were quantified by imaging analysis program (Q-IHC, http://www.bio-miblab.org).Results:The uptake of trastuzumab by QHerceptest was heterogenous, varying between 1.3% to 193.7%. Twenty one of 31 (67.7%) patients achieved pathologic complete response (pCR): 11 of 12 patients (91.7%) with QHerceptest strong positive tumors, 6 of 9 patients (66.7%) with QHerceptest moderate positive tumors, and 4 of 7 patients (57.1%) with QHerceptest weak positive tumors, and none of 3 patients (9.4%) with QHerceptest negative tumors (p=0.0203). Besides, RU was significantly different between non-pCR and pCR groups (43.9±38.3, 80.8±47.1, p=0.0396)Conclusion:We developed a new HER2 assay using trastuzumab and applied to clinical specimen. This assay showed heterogenous trastuzumab uptake in this patient population. Although the data need to be verified by further study, the assay could possibly eliminate patients among HER2 positive breast cancer who will not get benefit by trastuzumab .This study was supported by NCC Grant No 0710292-2 and NCC Grant No 0610240.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 6050.

Use of tumor volume as measured on F18FDG-PET/CT scan as a predictive biomarker for head and neck cancer

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Background: Functional imaging, PET and its fusion with anatomical modalities, PET/CT promise to improve detection and characteristic disease. The objective of this study was to evaluate metabolic tumor volume as measured on F-18 FDG-PET/CT and its association with treatment response and prognosis in patients with head and neck cancer. Methods: The study population consisted of patients received neoadjuvant chemotherapy for a maximum of three cycles followed by radiation therapy. Before treatment patients were taken FDG-PET/CT scan, SUVmax, tumor volume, metastasis were recorded. Results: We enrolled 59 patients with stage III ann IV head and neck cancer. The median age was 66 years (range 47–81). There were 32 patients with stage III and 27 with stage IV. The mean SUVmax was 8.8 (range, 1.478). The mean tumor volume was 21.3 cm3 (range, 0.2–170). There was no correlation between tumor volume and SUVmax (correlation coefficient 0.295). Higher SUVmax was not associated with an increased risk of lymph node and distant metastasis at diagnosis (p = 0.968). But higher tumor volume was associated with an increased risk of lymph node and distant metastasis at diagnosis (p = 0.063). The metabolic tumor volume as measured on PET/CT scans was predictor of treatment response and disease -free survival. The response rate were 84% (21/25) for an SUVmax <5.5, 55% (19/34) for an SUVmax > 5.5 (p = 0.038). The disease free survival were 31.1month for an SUVmax <5.5, 4.6months for an SUVmax > 5.5 (p = 0.025). Conclusions: The metabolic tumor volume as measured on F-18FDG-PET/CT is a predictive biomarker of treatment response and disease free survival for patients with head and neck cancer.

No significant financial relationships to disclose.

Detection of porcine circovirus 2 in mammary and other tissues from experimentally infected sows

The aim of this study was to determine whether porcine circovirus 2 (PCV2) may infect the mammary gland of sows and be shed in the milk. Six pregnant sows were inoculated intranasally with PCV2 three weeks before their expected farrowing date and two further sows acted as uninfected controls. The animals remained clinically healthy and farrowed normally. Milk samples were collected from all sows on the first, second and third days of lactation. PCV2 DNA was detected in the milk of infected sows from day 1 of lactation but not in the milk of uninfected controls. PCV2 antigen and DNA were detected in the mammary gland and other tissues by immunohistochemistry and in-situ hybridization, respectively. Simultaneous detection of viral protein and DNA provided molecular evidence of PCV2 infection and replication within these tissues.

4-1 BB stimulation inhibits allergen-specific immunoglobulin E production and airway hyper-reactivity but partially suppresses bronchial eosinophilic inflammation in a mouse asthma model

BACKGROUND

4-1 BB, a member of the tumour necrosis factor receptor superfamily, functions as a co-stimulatory molecule. Recently, stimulation of the 4-1 BB pathway was shown to suppress antigen-specific CD4(+) T cell and subsequent T cell-dependent humoral immune responses.

OBJECTIVE

We examined the effect of agonistic anti-4-1 BB monoclonal antibody (mAb) treatment on allergic asthma, in which allergen-specific type 2 helper T cells (Th2) have been shown to play an important role.

METHODS

BALB/c mice were systemically sensitized with intraperitoneal injections of ovalbumin (OVA) and alum on days 0 and 14, and then challenged with inhaled OVA on days 28, 29 and 30. In test groups, the agonistic anti-4-1 BB mAb was administered at the time of initial systemic sensitization with OVA. On day 31, mice were challenged with inhaled methacholine, and enhanced pause was measured as an index of airway hyper-responsiveness (AHR). Levels of OVA-specific IgE in serum, and levels of various cytokines in bronchoalveolar lavage (BAL) fluids were measured. The severity of airway inflammation was determined by differential cell counts in BAL fluids and histopathologic lung analysis. To evaluate local immunity, we cultured lymphocytes from draining perihilar lymph nodes and evaluated the proliferative response to OVA and the levels of IL-5 in the culture supernatant. In addition, the functional mechanism of 4-1 BB stimulation was evaluated in splenocytes obtained at day 7 after systemic OVA sensitization.

RESULTS

We found that treatment with the anti-4-1 BB mAb significantly decreased AHR and the production of allergen-specific IgE. Bronchial inflammation, however, had only partially improved and the levels of IL-4 and IL-5 in BAL fluids showed only a small degree of reduction compared with the control Ig-treated mice. Thoracic lymphocytes from anti-4-1 BB-treated mice showed significant suppression of OVA-induced proliferation and IL-5 production. In anti-4-1 BB-treated mice, splenocytes exhibited poor proliferation and marked apoptosis 7 days after systemic OVA challenge.

CONCLUSION

These results suggest that stimulation of the 4-1 BB pathway effectively suppresses some features of allergic asthma, including allergen-specific IgE production and AHR, through deletion of allergen-specific Th2 cells. However, we found that bronchial allergic inflammation was not strictly mediated by suppression of the Th2 immune response in this murine model of asthma. Despite these somewhat contradictory effects, intervention in the 4-1 BB pathway might provide a potential novel immunotherapeutic approach for treatment of allergic asthma.

Blockade of 4-1BB (CD137)/4-1BB ligand interactions increases allograft survival

We investigated the role of 4-1BB, a T cell co-stimulatory molecule, in alloimmune responses. In vivo mixed lymphocyte reactions showed that 4-1BB was preferentially expressed on actively dividing CD4(+) and CD8(+) T cells. Furthermore, following alloantigen challenge, the draining lymph nodes contained subpopulations of 4-1BB-expressing CD4(+) and CD8(+) T cells. 4-1BB-deficient C57BL/6 mice showed a delayed rejection of cardiac transplants mismatched for the major histocompatibility complex. Longer transplant survival was induced by blockade of 4-1BB/4-1BB ligand (4-1BBL) interactions using an anti-4-1BBL monoclonal antibody. Histological analysis showed that prolonged transplant survival in the 4-1BB-deficient and anti-4-1BBL-treated mice correlated with reduced lymphocytic infiltration and vasculitis in the donor heart tissue. Taken together, our data suggest that blockade of 4-1BB/4-1BBL interactions inhibited the expansion of alloreactive T cells and reduced CTL activity against host alloantigen, which in turn resulted in the prolongation of allograft survival. Blockade of the 4-1BB co-stimulatory pathway may be useful for preventing allograft rejection.

Tumor necrosis factor receptor superfamily 14 is involved in atherogenesis by inducing proinflammatory cytokines and matrix metalloproteinases

Tumor necrosis factor (TNF) receptor superfamily 14 (TNFRSF14) is the cellular receptor for TNF superfamily 14 (LIGHT). Immunohistochemical staining of human carotid atherosclerotic plaques revealed a high level of expression of the TNFRSF14 in regions rich in macrophages/foam cells. To investigate the role of TNFRSF14 in the functioning of monocytes in relation to atherogenesis, we have analyzed TNFRSF14 expression levels and cellular events after stimulation of TNFRSF14 in peripheral blood monocytes or the human macrophage-like cell line, THP-1. A high level of expression of TNFRSF14 was detected in activated monocytes, in macrophages derived from monocytes, and in THP-1 cells. Concomitant activation of THP-1 cells with interferon-gamma and immobilized anti-TNFRSF14 monoclonal antibody resulted in synergistic induction of proatherogenic cytokines, such as TNF-alpha and interleukin-8. Activation of THP-1 cells with immobilized anti-TNFRSF14 monoclonal antibody induced expression of matrix metalloproteinase (MMP)-1, MMP-9, MMP-13, and tissue inhibitors of metalloproteinase-1 and -2. Furthermore, immunohistochemical staining of atherosclerotic plaques with severe infiltration of foam cells revealed that the expression patterns of TNFRSF14 and MMP-1, -9, and -13 overlapped. Treatment of THP-1 cells with soluble LIGHT also caused induction of MMP-9 and interleukin-8. These data suggest that TNFRSF14 is involved in atherosclerosis via the induction of proatherogenic cytokines and decreasing plaque stability by inducing extracellular matrix-degrading enzymes.

Host T cells resist graft-versus-host disease mediated by donor leukocyte infusions

Delayed lymphocyte infusions (DLIs) are used to treat relapse occurring post bone marrow transplantation (BMT) and to increase the donor chimerism in recipients receiving nonmyeloablative conditioning. As compared with donor lymphocytes given early post-BMT, DLIs are associated with a reduced risk of graft-vs-host disease (GVHD). The mechanism(s) responsible for such resistance have remained incompletely defined. We now have observed that host T cells present 3 wk after lethal total body irradiation, at the time of DLI, contribute to DLI-GVHD resistance. The infusion of donor splenocytes on day 0, a time when host bone marrow (BM)-derived T cells are absent, results in greater expansion than later post-BMT when host and donor BM-derived T cells coexist. Selective depletion of host T cells with anti-Thy1 allelic mAb increased the GVHD risk of DLI, indicating that a Thy1(+) host T cell regulated DLI-GVHD lethality. The conditions by which host T cells are required for optimal DLI resistance were determined. Recipients unable to express CD28 or 4-1BB were as susceptible to DLI-GVHD as anti-Thy1 allelic mAb-treated recipients, indicating that CD28 and 4-1BB are critical to DLI-GVHD resistance. Recipients deficient in both perforin and Fas ligand but not individually were highly susceptible to DLI-GVHD. Recipients that cannot produce IFN-gamma were more susceptible to DLI-GVHD, whereas those deficient in IL-12 or p55 TNFRI were not. Collectively, these data indicate that host T cells, which are capable of generating antidonor CTL effector cells, are responsible for the impaired ability of DLI to induce GVHD. These same mechanisms may limit the efficacy of DLI in cancer therapy under some conditions.

4-1BB: still in the midst of darkness

4-1BB is a member of the tumor necrosis factor receptor superfamily. The receptor functions mainly as a costimulatory molecule in T lymphocytes. In addition, several lines of evidence have shown that interactions between 4-1BB and its ligand are involved in the antigen presentation process and the generation of cytotoxic T cells. Recent studies, however, have demonstrated that 4-1BB plays more diverse roles: Signals through 4-1BB are important for long-term survival of CD8+ T cells and the induction of helper T cell anergy. Clinically, there is great interest in 4-1BB, because T-cell activation induced by anti-4-1BB monoclonal antibodies is highly efficient in the eradication of established tumor cells in mice. Now, since mice deficient in 4-1BB or the 4-1BB ligand are available, subtle roles played by 4-1BB may be revealed in the near future.

Increased severity of Pseudomonas aeruginosa corneal infection in strains of mice designated as Th1 versus Th2 responsive

PURPOSE

Mice favoring Th1 (C57BL/6, C57BL/10, and B10.D2/nSn) versus Th2 (BALB/c, BALB/cBy, BALB.B, and BALB.K) response development were evaluated for their response to infection with Pseudomonas aeruginosa. This study addresses the question of whether Th1 versus Th2 response propensity affects the pathogenesis of bacterial keratitis in mice.

METHODS

Ocular disease was determined by mean clinical score, slit lamp, plate counts, and histopathology, and antigen-specific cellular responses were assessed by immunostaining and measurement of delayed type hypersensitivity (DTH).

RESULTS

Strains of mice favoring Th1 (B6, BL10, and B10.D2) versus Th2 (BALB/c, BALB/cBy, BALB.B, and BALB.K) responsiveness were infected with P. aeruginosa. Mice favoring Th1 response development exhibited a similar course of disease and the infected eyes of all mice perforated by 7 days postinfection (p.i.). Strains (BALB/c, BALB/cBy, BALB.B, and BALB.K) favoring Th2 response development exhibited a milder course of disease, and none of the infected corneas perforated at 7 days p.i. In a Th1-responsive strain (B10.D2), positive immunostaining for CD4+ and CD8+ T cells was observed in the cornea by 3 days p.i. and by 5 days p.i., respectively, some cells stained positively for IL2-R, indicating that the cells were activated. In contrast, in a Th2 responder strain (BALB/c), there was no detectable positive immunostaining in cornea for any of the T-cell markers tested and DTH was significantly elevated in B10.D2 versus BALB/c mice.

CONCLUSIONS

These studies are the first to provide evidence that in P. aeruginosa ocular infection, mouse strains favoring development of a Th1-type response are susceptible (cornea perforates), whereas strains favoring Th2 response development are resistant (no corneal perforation).

Functions of newly identified members of the tumor necrosis factor receptor/ligand superfamilies in lymphocytes

Rapid progress in the discovery of members of the tumor necrosis factor receptor/ligand superfamilies has been made, mainly with the help of massive DNA sequencing and bioinformatic studies. Biological studies of the new members have not only indicated overlapping roles with other members but also provided insights into novel functions. In particular, multiple pairings of receptors and ligands highlight a complex control mechanism of immune responses by these superfamilies.

A newly identified member of tumor necrosis factor receptor superfamily (TR6) suppresses LIGHT-mediated apoptosis

TR6 (decoy receptor 3 (DcR3)) is a new member of the tumor necrosis factor receptor (TNFR) family. TR6 mRNA is expressed in lung tissues and colon adenocarcinoma, SW480. In addition, the expression of TR6 mRNA was shown in the endothelial cell line and induced by phorbol 12-myristate 13-acetate/ionomycin in Jurkat T leukemia cells. The open reading frame of TR6 encodes 300 amino acids with a 29-residue signal sequence but no transmembrane region. Using histidine-tagged recombinant TR6, we screened soluble forms of TNF-ligand proteins with immunoprecipitation. Here, we demonstrate that TR6 specifically binds two cellular ligands, LIGHT (herpes virus entry mediator (HVEM)-L) and Fas ligand (FasL/CD95L). These bindings were confirmed with HEK 293 EBNA cells transfected with LIGHT cDNA by flow cytometry. TR6 inhibited LIGHT-induced cytotoxicity in HT29 cells. It has been shown that LIGHT triggers apoptosis of various tumor cells including HT29 cells that express both lymphotoxin beta receptor (LTbetaR) and HVEM/TR2 receptors. Our data suggest that TR6 inhibits the interactions of LIGHT with HVEM/TR2 and LTbetaR, thereby suppressing LIGHT- mediated HT29 cell death. Thus, TR6 may play a regulatory role for suppressing in FasL- and LIGHT-mediated cell death.

Identification of a novel activation-inducible protein of the tumor necrosis factor receptor superfamily and its ligand

Among members of the tumor necrosis factor receptor (TNFR) superfamily, 4-1BB, CD27, and glucocorticoid-induced tumor necrosis factor receptor family-related gene (GITR) share a striking homology in the cytoplasmic domain. Here we report the identification of a new member, activation-inducible TNFR family member (AITR), which belongs to this subfamily, and its ligand. The receptor is expressed in lymph node and peripheral blood leukocytes, and its expression is up-regulated in human peripheral mononuclear cells mainly after stimulation with anti-CD3/CD28 monoclonal antibodies or phorbol 12-myristate 13-acetate/ionomycin. AITR associates with TRAF1 (TNF receptor-associated factor 1), TRAF2, and TRAF3, and induces nuclear factor (NF)-kappaB activation via TRAF2. The ligand for AITR (AITRL) was found to be an undescribed member of the TNF family, which is expressed in endothelial cells. Thus, AITR and AITRL seem to be important for interactions between activated T lymphocytes and endothelial cells.

Antibody to transforming growth factor beta reduces collagen production in injured peripheral nerve

Epineurial scarring in peripheral nerve after injury inhibits normal axonal regeneration primarily due to fibroblast deposition of type I collagen. The transforming growth factor beta (TGF-beta) family is an important class of signaling molecules that has been shown to stimulate fibroblasts to produce collagen. The aim of this study was to design a prototypic therapeutic system in which the neutralization of TGF-beta in crushed rat sciatic nerve would decrease collagen formation. A total of 45 experimental Lewis rats were used. Group 1 animals (20 rats) sustained a unilateral crush injury to the sciatic nerve with injection of phosphate buffer solution. Group 2 animals (20 rats) sustained a unilateral crush injury to the sciatic nerve with injection of phosphate-buffered saline and goat, anti-rat, panspecific TGF-beta antibody. Group 3 control animals (five rats) underwent only exposure of sciatic nerve with injection of antibody. All animals were killed at 14 days and sciatic nerve specimens were harvested at that time. Slides of experimental tissue were processed using a 35S-labeled oligomer for procollagen alpha-1 mRNA, then dipped in photographic emulsion and examined by darkfield autoradiography. Morphometric analysis of pixel counts was then performed. A significant reduction in total pixel count per high-power field and in total number of fibroblasts per high-power field was found in crushed rat sciatic nerve treated with anti-TGF-beta antibody when compared with those treated only with phosphate-buffered saline. These findings are consistent with successful reduction in procollagen induction after a crush injury by topical administration of blocking antibody against transforming growth factor beta. The concept of growth factor blockade for therapeutic collagen reduction is attractive in the context of nerve injury, and the current article provides a model for future clinical application.

Association of CD4+ T cell-dependent keratitis with genetic susceptibility to Pseudomonas aeruginosa ocular infection

The role of T lymphocytes in susceptibility to Pseudomonas aeruginosa corneal infection was studied in inbred C57Bl/6 (B6) beta2-microglobulin+/+ (beta2m+/+) and beta2m-/- knockout (KO) mice on a B6 genetic background. The corneas of both B6 and KO mice perforated by 7 days postinfection (p.i.). Histopathology revealed a similar inflammatory response characterized by an infiltration of polymorphonuclear neutrophilic leukocytes by 24 h p.i. in both groups of mice. CD4+ and CD8+ (latter absent in KO) T cells were present in cornea by 3 days p.i., and by 5 days, IL-2R-positive cells were positively immunostained. Corneas of B6 beta2m+/+ mice depleted of CD4+ T cells and infected with P. aeruginosa did not perforate at 7 days p.i. vs mice depleted of CD8+ T cells or treated with an irrelevant mAb. Neutralization of IFN-gamma before infecting B6 mice prevented corneal perforation and was associated with a lower delayed-type hypersensitivity than in B6 mice similarly treated with an irrelevant mAb. These data provide evidence that a CD4+ T cell (Th1)-dominated response following P. aeruginosa corneal infection is associated with genetic susceptibility and corneal perforation in inbred B6 mice.

Association of CD4+ T cell-dependent keratitis with genetic susceptibility to Pseudomonas aeruginosa ocular infection

The role of T lymphocytes in susceptibility to Pseudomonas aeruginosa corneal infection was studied in inbred C57Bl/6 (B6) beta2-microglobulin+/+ (beta2m+/+) and beta2m-/- knockout (KO) mice on a B6 genetic background. The corneas of both B6 and KO mice perforated by 7 days postinfection (p.i.). Histopathology revealed a similar inflammatory response characterized by an infiltration of polymorphonuclear neutrophilic leukocytes by 24 h p.i. in both groups of mice. CD4+ and CD8+ (latter absent in KO) T cells were present in cornea by 3 days p.i., and by 5 days, IL-2R-positive cells were positively immunostained. Corneas of B6 beta2m+/+ mice depleted of CD4+ T cells and infected with P. aeruginosa did not perforate at 7 days p.i. vs mice depleted of CD8+ T cells or treated with an irrelevant mAb. Neutralization of IFN-gamma before infecting B6 mice prevented corneal perforation and was associated with a lower delayed-type hypersensitivity than in B6 mice similarly treated with an irrelevant mAb. These data provide evidence that a CD4+ T cell (Th1)-dominated response following P. aeruginosa corneal infection is associated with genetic susceptibility and corneal perforation in inbred B6 mice.

Extensive nodular sarcoidosis in the hand

We report an atypical case of nodular sarcoidosis involving both hands. The pattern of extensive involvement of all digits with lesions extending into the pulp spaces has not been reported previously. The diagnosis of sarcoidosis should be considered even in patients presenting with clinically uncharacteristic manifestations.

Radiographic assessment of the trapezial space before and after ligament reconstruction and tendon interposition arthroplasty

A radiographic method was developed, the trapezial space ratio, for assessing the space occupied by the trapezium (a space defined by the distal scaphoid and thumb metacarpal base divided by the thumb proximal phalanx). This method was applied to 100 normal thumb radiographs and to the radiographs of 15 patients with symptomatic degenerative arthrosis of the thumb basal joint before and after operative treatment with ligamentous reconstruction and tendon interposition arthroplasty. The trapezial space ratio averaged 0.476 +/- 0.033 for radiographs of normal thumbs, 0.372 +/- 0.084 for the pre-operative radiographs of thumbs with symptomatic basal joint arthrosis, and 0.270 +/- 0.078 for the radiographs of thumbs following basal joint arthroplasty. A significant reduction in the trapezial space ratio was noted when values from arthritic thumbs were compared to those of normal thumbs (22%; P < 0.0001). A further reduction in the trapezial space ratio was noted when post-operative values were compared to pre-operative ones (27%; P < 0.0002). Comparing post-operative trapezial space ratio values to values obtained in normal thumbs, a reduction of 43% was found in those thumbs treated operatively. These finding indicate that the trapezial space is reduced significantly in thumbs with severe degenerative arthrosis compared to normal thumbs and that ligament construction tendon interposition arthroplasty is not entirely successful in either restoring or maintaining the length of the thumb ray.

Relative densities of muscarinic cholinergic and beta-adrenergic receptors in the canine sinoatrial node and their relation to sites of pacemaker activity

The site of earliest extracellular electrical activation in the sinoatrial node (SAN) is known to shift in response to autonomic stimuli, but the mechanisms underlying this phenomenon and the determinants of the location of dominant pacemaker activity have not been elucidated. The present study was designed to characterize the spatial distribution of muscarinic cholinergic and beta-adrenergic receptors in the canine SAN and to determine whether a consistent relationship exists between autonomic receptor densities and the site of dominant pacemaker activity. We used quantitative light-microscopic autoradiography of radioligand binding sites to characterize the spatial distribution of muscarinic cholinergic and beta-adrenergic receptor subtypes in tissue sections containing the SAN and adjacent right atrial muscle from 18 canine hearts. Muscarinic receptor density was 5.4 times greater in SAN cells than in atrial myocytes (P < .01). Total beta-adrenergic receptor density was more than 3 times greater in SAN cells than in atrial myocytes (P < .0001), due entirely to the significantly greater number of beta 1-adrenergic receptors in the SAN. The region of dominant pacemaker activity, localized in 4 hearts with in vitro mapping, consistently exhibited greater densities of muscarinic and beta 1-adrenergic receptors than other SAN regions. Muscarinic receptor density in the dominant pacemaker region was 18 +/- 2% and 29 +/- 7% higher than in adjacent superior and inferior regions, respectively. beta 1-Receptor density in the dominant site was 53 +/- 5% and 26 +/- 4% higher than in adjacent superior and inferior SAN regions, respectively. Thus, the SAN is richly endowed with both muscarinic cholinergic and beta 1-adrenergic receptors.(ABSTRACT TRUNCATED AT 250 WORDS)

Mapping the bovine albino locus

The albino, beta-hemoglobin, and lactate dehydrogenase A (LDHA) loci comprise a highly conserved syntenic group in those mammals in which the three loci have been genetically mapped. In this study, we used a tyrosinase probe to map the bovine albino locus, using a panel of bovine-hamster hybrid cells in which HBB, LDHA, and a number of other loci had previously been mapped. The probe was a human tyrosinase cDNA clone (Pme134) which has been mapped to the c (albino) locus in mice. Although beta-hemoglobin is linked to the albino locus in mice, rats, cats, and rabbits, the two loci are not syntenic in cattle. The tyrosinase probe, however, dose hybridize to a fragment that is syntenic with lactate dehydrogenase A in cattle. Since HBB is syntenic with catalase (CAT) in both humans and cattle, while catalase is asyntenic with HBB in mice, at least two chromosomal rearrangements are required to account for the chromosomal relationships of HBB, CAT, LDHA, and the albino locus in these three species.

Polymerization of murine macrophage inflammatory protein 1 alpha inactivates its myelosuppressive effects in vitro: the active form is a monomer

Macrophage inflammatory protein (MIP) 1 alpha has myelosuppressive and myeloprotective activity. That MIP-1 alpha polymerizes is known; this phenomenon was evaluated in terms of myelosuppression by assessing the effects of recombinant murine MIP-1 alpha on colony formation of murine and human myeloid progenitor cells in vitro. The following results are reported: (i) Polymerization is diluent- and concentration-dependent. (ii) Monomeric MIP-1 alpha is the active suppressive form for myeloid progenitor cells in vitro. (iii) Polymerized MIP-1 alpha is inactive and does not interfere with suppression by monomeric MIP-1 alpha. (iv) MIP-1 alpha has approximately 1000-fold higher specific activity than has been reported, but its effects are still specific for immature subsets of myeloid progenitors. (v) Suppression is initiated during the DNA-synthesis phase of the cell cycle. We conclude that polymerization of MIP-1 alpha might be a control mechanism that limits the myelosuppressive effects of monomeric MIP-1 alpha.

Exclusion of two candidate pigment loci, c and b, part of chromosome 11p, and 33 random polymorphic markers as the locus for tyrosinase-positive oculocutaneous albinism

The locus for Tyrosinase-Positive Oculocutaneous Albinism (ty-pos OCA) has not yet been localised. The search for the ty-pos OCA locus has included a search for linkage to candidate pigment loci and a candidate chromosomal region, as well as a random search using highly polymorphic markers in 42 families, including 271 individuals of whom 79 are affected. The lod scores for the tyrosinase (TYR) locus (11q14-q21), homologous to the albino locus, c, in the mouse and the CAS2/TRP1 locus (9p22-pter), homologous to the brown locus, b, in the mouse were -5.89 and -7.22, respectively, at a recombination fraction of theta = 0.01, thus excluding them from being the ty-pos OCA locus. In the candidate chromosomal region, 11p, four loci (probes) were tested, SAA (pSAA82), CALC (pHC36), HBB (Gamma-globin haplotype) and an AC repeat polymorphism at the Wilm's Tumour locus (WT1). A portion of 11p was excluded with the following lod scores: pSAA82 lod = -2.05 at theta = 0.10; pHC36 lod = -3.87 at theta = 0.05; gamma-globin haplotype lod = -2.80 at theta = 0.10; and WT1 lod = -2.34 at theta = 0.10. Thirty-three polymorphic markers randomly distributed on 13 different chromosomes were all excluded from close linkage to ty-pos OCA.

A two allele XbaI RFLP at the catalase 2 locus

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Characterization of multiple forms of small collagenous apatite-binding proteins in bone

A number of small (Mrs 25-28 kDa) collagenous apatite-binding (SCAB) proteins that stain blue with 'Stains-All' have been isolated from fetal porcine bone by sequential extractions with 4M GuHCl (G1), followed by 0.5M EDTA (E), and again with 4M GuHCl (G2). Following purification under dissociative conditions, two types of SCAB proteins both with approximately one-third of their structure being collagenous, were identified in the EDTA extract. One type, which appears to be a novel protein, was revealed in two forms (SCABs 1 and 2, Mrs 25 and 28 kDa) that were recognized by a monoclonal antibody (MBP-322). The second type, SCAB 3, was also present in two forms; one form (SCAB 3a) having a lower affinity for hydroxyapatite than the other (SCAB 3b). These proteins were resistant to CNBr and displayed the chemical and immunochemical properties of the alpha 1 pN-propeptide of type I collagen. A third form of the propeptide (G2-28K) was a prominent component of the second 4M GuHCl extract. The chromatographic properties of serum alpha 1 (I) pN-propeptide were similar to SCAB 3a, indicating that SCAB 3b and G2-28K are post-translationally modified forms of the propeptide produced by bone cells. These propeptides may provide a link between the hydroxyapatite and collagen fibrils, and also have the potential to suppress collagen synthesis during bone resorption.

Multiple transcripts of the mouse tyrosinase gene are generated by alternative splicing

We report the cloning and isolation of the mouse tyrosinase cDNA by screening mouse B16 melanoma cDNA libraries. Independent cDNA clones have been characterized by restriction enzyme analysis, hybridizations with individual subprobes and by partial sequencing analysis. Based on these criteria we have identified multiple transcripts, which in comparison to the major transcript, display deletions of internal sequences and have different 3' termini. The most abundant transcript encodes a functional tyrosinase. The structural gene which encodes five exons separated by large introns and spans a chromosomal region of approximately 70 kb has been isolated. Comparison of the cDNAs with the cloned genomic DNAs and sequencing of the exon/intron boundaries reveal that the multiple transcripts are generated by alternative splicing and putatively by alternate polyadenylation site usage. The alternative splicing mechanisms involve exon skipping as well as internal donor splice site usage. Primer extension analysis shows that the transcripts are produced from two different promoters. Southern blot analysis of DNAs derived from mice carrying the lethal albino deletion mutations demonstrates that the structural gene maps near or at the albino locus. The viable albino mouse BALB/c carries an apparently intact structural gene indicating that the albino phenotype is a consequence of a failure to express the tyrosinase gene or the inability to produce a tyrosinase enzyme.