Use of Anti-Glycopeptidolipid-Core Antibodies Serology for Diagnosis and Monitoring of Mycobacterium avium Complex Pulmonary Disease in the United States.

Background: There is an unmet need for rapid, accurate, and noninvasive assays for diagnosis and monitoring of Mycobacterium avium complex pulmonary disease (MAC-PD). We evaluated the diagnostic accuracy of an anti-glycopeptidolipid (GPL)-core immunoglobulin A (IgA) antibody test in a US cohort of MAC patients, and we described serial serology changes during antimicrobial therapy. Methods: We identified serum samples from MAC patients starting treatment at enrollment and control subjects with or without bronchiectasis within OHSU's NTM Biobank. We conducted diagnostic test accuracy. Changes in mean levels of anti-GPL-core IgA antibodies between 0 and 3, 6, or 12 months after treatment start were assessed using the Student's paired t test. Pearson's correlation coefficient was calculated for IgA antibody levels and Student paired t test measures. Results: We included 25 MAC patients and 18 controls. At baseline, IgA antibody concentrations in MAC patients (3.40 ± 6.77 U/mL) were significantly higher than in controls without bronchiectasis (0.14 ± 0.03 U/mL, P = .02). Sensitivity and specificity for MAC-PD in this population was 48% and 89% (cutoff point 0.7 U/mL), respectively. Among MAC patients starting antimicrobial therapy, mean IgA levels decreased 0.3202 U/mL (P = .86) at month 3, 0.8678 U/mL (P = .47) at month 6, and 1.9816 U/mL (P = .41) at 1 year. Quality of Life-Bronchiectasis Respiratory Symptom Scale improvement correlated with decreasing IgA titers after 12 months of treatment in MAC patients (r = -0.50, P = .06). Conclusions: Anti-GPL-core IgA antibody levels are relatively specific for MAC-PD and decrease with treatment. Larger studies are warranted to evaluate the role of IgA serology in monitoring treatment response or for disease relapse/reinfection.

Epiteliopatía en limpiaparabrisas en pacientes con blefaroespasmo o espasmo hemifacial / Lid wiper epitheliopathy in patients with blepharospasm and/or hemifacial spasm

Objetivo Evaluar la presencia de epiteliopatía en limpiaparabrisas en pacientes con blefaroespasmo o espasmo hemifacial antes del tratamiento habitual con toxina botulínica y 4 semanas después. Métodos Estudio prospectivo compuesto por 31 ojos de 20 pacientes con diagnóstico neurológico de espasmo hemifacial (9 ojos de 9 pacientes) y blefaroespasmo esencial (22 ojos de 11 pacientes). Se evaluaron antes y 4 semanas después de la infiltración con toxina botulínica diversos parámetros de superficie ocular con el cuestionario OSDI, test de Schirmer, tiempo de rotura lagrimal y tinciones de fluoresceína y verde de lisamina valoradas con el test de Oxford y el grado de afectación del limpiaparabrisas palpebral. Resultados El 100% de los pacientes presentaron afectación del limpiaparabrisas palpebral antes (30% grado leve y 70% moderado) y después del tratamiento con toxina (100% grado leve). El 75% de los pacientes presentaron un OSDI normal-leve antes del tratamiento; después del tratamiento fue del 80%. El tiempo de rotura lagrimal fue de 7,2±0,2 s antes y de 7,5±0,7 s después del tratamiento. El test de Schirmer fue de 11,4±5,5 y 12,5±5,5mm antes y después del tratamiento. El test de Oxford resultó patológico inicialmente en el 69,3% de los pacientes; tras 4 semanas solo fue patológico en el 54%. Conclusión La epiteliopatía en limpiaparabrisas está presente en el 100% de los pacientes con blefaroespasmo o espasmo hemifacial. El principal mecanismo fisiopatológico que la desencadena en estos pacientes es el aumento en el coeficiente de fricción, ya que el volumen y la estabilidad lagrimal son normales (AU)

Objective To evaluate the presence of wiper epitheliopathy in patients with blepharospasm and/or hemifacial spasm before and 4 weeks after routine treatment with botulinum toxin. Methods Prospective study comprising 31 eyes of 20 patients with neurological diagnosis of hemifacial spasm (9 eyes of 9 patients) and essential blepharospasm (22 eyes of 11 patients). Various ocular surface parameters were assessed before and 4 weeks after infiltration with botulinum toxin using the OSDI questionnaire, Schirmer's test, tear break-up time, fluorescein and lissamine green staining assessed with the Oxford test and the degree of involvement of the palpebral wiper. Results 100% of the patients had palpebral wiper involvement before (30% mild and 70% moderate) and after toxin treatment (100% mild). 75% of patients had mild-normal OSDI before treatment, after treatment it was 80%. The tear break-up time was 7.2±0.2 sg before and 7.5±0.7 sg after treatment. Schirmer's test was 11.4±5.5 and 12.5±5.5mm before and after treatment. The Oxford test was initially pathological in 69.3% of patients, after 4 weeks it was pathological in only 54%. Conclusion Wiper epitheliopathy is present in 100% of patients with blepharospasm and/or hemifacial spasm. The main pathophysiological mechanism that triggers it in these patients is the increase in the coefficient of friction, as tear volume and stability are norma (AU)

Lid wiper epitheliopathy in patients with blepharospasm and/or hemifacial spasm.

OBJECTIVE: To evaluate the presence of wiper epitheliopathy in patients with blepharospasm and/or hemifacial spasm before and 4 weeks after routine treatment with botulinum toxin. METHODS: Prospective study comprising 31 eyes of 20 patients with neurological diagnosis of hemifacial spasm (9 eyes of 9 patients) and essential blepharospasm (22 eyes of 11 patients). Various ocular surface parameters were assessed before and 4 weeks after infiltration with botulinum toxin using the OSDI questionnaire, Schirmer's test, tear break-up time (BUT), fluorescein and lissamine green staining assessed with the Oxford test and the degree of involvement of the palpebral wiper. RESULTS: 100% of the patients had palpebral wiper involvement before (30% mild and 70% moderate) and after toxin treatment (100% mild). 75% of patients had mild-normal OSDI before treatment, after treatment it was 80%. The BUT was 7.2 ±â€¯0.2 sg before and 7.5 ±â€¯0.7 sg after treatment. Schirmer's test was 11.4 ±â€¯5.5 and 12.5 ±â€¯5.5 mm before and after treatment. The Oxford test was initially pathological in 69.3% of patients, after 4 weeks it was pathological in only 54%. CONCLUSION: Wiper epitheliopathy is present in 100% of patients with blepharospasm and/or hemifacial spasm. The main pathophysiological mechanism that triggers it in these patients is the increase in the coefficient of friction, as tear volume and stability are normal.

Evaluation of the stability of Yamakagashi (Rhabdophis tigrinus) Equine Antivenom after 20 years storage.

In 2000, an equine Yamakagashi (Rhabdophis tigrinus) antivenom (Lot 0001) was testmanufactured as an unapproved drug for treatment of Yamakagashi bites. It was stocked on the premise of super-legal use from the viewpoint of emergency health crisis management. The antivenom showed a strong neutralizing ability against the hemorrhagic and coagulation activity of the Yamakagashi venom in its potency test. One vial of the antivenom can effectively neutralize at least about 4 mg of Yamakagashi venom. Its efficacy has also been confirmed in patients with severe cases of R. tigrinus bite that has been used in emergency. In 2020, this antivenom (Lot 0001) has reached 20 years after its production. To evaluate the integrity and potency of the antivenom, quality control, safety and potency tests had been conducted almost every year since 2012. Physical and chemical tests (property test, moisture content test, insoluble foreign matter test, osmotic pressure ratio test, pH test, protein content test, endotoxin test, sterility test) of the antivenom, showed no significant changes throughout the years, when compared to the results immediately after its production in 2000. All the parameters measured were also within the standard values. In animal safety tests (test for absence of toxicity and pyrogen), there was no change in the test results during the storage period and no abnormalities were observed. The potency test (anti-coagulant activity) after 20 years of the product, showed the same potency as those recorded immediately after production. Therefore, in all of the stability monitoring tests conducted so far, the product did not show any significant change compared to the results immediately after production. This confirms the stability of the product during the stockpiling period to the present, that is, 20 years after production.

Evaluation of the stability of Yamakagashi (Rhabdophis tigrinus) Equine Antivenom after 20 years storage

@#In 2000, an equine Yamakagashi (Rhabdophis tigrinus) antivenom (Lot 0001) was testmanufactured as an unapproved drug for treatment of Yamakagashi bites. It was stocked on the premise of super-legal use from the viewpoint of emergency health crisis management. The antivenom showed a strong neutralizing ability against the hemorrhagic and coagulation activity of the Yamakagashi venom in its potency test. One vial of the antivenom can effectively neutralize at least about 4 mg of Yamakagashi venom. Its efficacy has also been confirmed in patients with severe cases of R. tigrinus bite that has been used in emergency. In 2020, this antivenom (Lot 0001) has reached 20 years after its production. To evaluate the integrity and potency of the antivenom, quality control, safety and potency tests had been conducted almost every year since 2012. Physical and chemical tests (property test, moisture content test, insoluble foreign matter test, osmotic pressure ratio test, pH test, protein content test, endotoxin test, sterility test) of the antivenom, showed no significant changes throughout the years, when compared to the results immediately after its production in 2000. All the parameters measured were also within the standard values. In animal safety tests (test for absence of toxicity and pyrogen), there was no change in the test results during the storage period and no abnormalities were observed. The potency test (anti-coagulant activity) after 20 years of the product, showed the same potency as those recorded immediately after production. Therefore, in all of the stability monitoring tests conducted so far, the product did not show any significant change compared to the results immediately after production. This confirms the stability of the product during the stockpiling period to the present, that is, 20 years after production.

Tasas de potencia de dos enfoques robustos para analizar datos longitudinales / Power rates of two robust approaches for the analysis of longitudinal data

El propósito del presente trabajo fue examinar la potencia de dos de las pruebas más novedosas, y quizás también más robustas, de cuantas se hallan disponibles actualmente para analizar datos longitudinales con matrices de dispersión arbitrarias. En concreto, se comparó la sensibilidad de la versión mejorada del procedimiento multivariado Brown-Forsythe con la potencia del enfoque del modelo mixto lineal con los grados de libertad corregidos mediante la técnica Satterthwaite de emparejar momentos en un diseño longitudinal con un factor de agrupamiento y otro de medidas repetidas. Por lo que respecta al efecto principal de las ocasiones de medida, el enfoque del modelo mixto resultó ser siempre más potente que el procedimiento BrownForsythe, sobre manera, cuando los tamaños de muestra eran pequeños. Cuando el interés se centró en los efectos de la interacción, se obtuvo un patrón de resultados similar; sin embargo, bajo esta condición las diferencias fueron menos acentuadas (AU)

Allograft inflammatory factor-1 augments production of interleukin-6, -10 and -12 by a mouse macrophage line.

Mouse allograft inflammatory factor-1 (AIF-1) cDNA was cloned and the AIF-1-specific monoclonal antibodies were established to examine its tissue distribution. The mouse AIF-1 was highly conserved among all reported AIF-1 from a variety of species, from invertebrates to mammals, and the cloned cDNA was in good accordance with putative expressed regions of genomic sequences in the mouse major histocompatibility complex (MHC) class III region. The messages of mouse AIF-1 were abundantly expressed in the testis, moderately in the spleen and lymph nodes and slightly in the liver and thymus of normal BALB/c mice. Immunohistological examination revealed that differentiating germ cells in the testis and presumably macrophages in the red pulp of the spleen were positive for AIF-1. To analyse the function of the AIF-1, a macrophage cell line, RAW 264.7, was transfected with mouse AIF-1 cDNA. Upon stimulation with bacterial lipopolysaccharide, the transfectants that overexpressed AIF-1 showed marked morphological changes and produced significantly large amounts of interleukin (IL)-6, IL-10 and IL-12p40 but not IL-12p70 compared with control cells. No difference was noted in production of tumour necrosis factor-alpha, transforming growth factor-beta1 and IL-1alpha. These results suggest that AIF-1 plays an important role in cells of a monocyte/macrophage lineage upon stimulation with inflammatory stimuli by augmenting particular cytokine production.

Mixed allogeneic chimerism with wild-type strains ameliorates atherosclerosis in apolipoprotein E-deficient mice.

Atherosclerosis involves inflammatory processes between vascular tissues and hematocytes with a hyperlipidemic background. To examine whether variations of hematocytes constitute one of the genetic components in atherosclerosis, irradiated apolipoprotein E (apoE)-deficient (apoE(-/-)) mice with hypercholesterolemia and preexisting atherosclerotic lesions were reconstituted with mixed bone marrow cells (BMC) from syngeneic and wild-type (apoE(+/+); atherosclerosis-resistant SJL or -susceptible B10.S) mice. Stable mixed allogeneic chimeras with small amounts of serum apoE were established without any detrimental complications. Compared with untreated apoE(-/-) mice or apoE(-/-) mice transplanted with syngeneic BMC alone, significant reduction of the cholesterol level and significant lesion regression were observed in the mixed chimeras. Furthermore, mixed chimeras given SJL BMC showed marked reductions in numbers of lesions compared with those reconstituted with B10.S BMC. Cholesterol levels in the former SJL chimeras, however, were significantly higher than those in the latter B10.S chimeras. These findings indicate that the resistance of SJL to atherosclerosis resides in the bone marrow-derived cells.

Amelioration of experimental autoimmune encephalomyelitis in C57BL/6 mice by an agonist of peroxisome proliferator-activated receptor-gamma.

Peroxisome proliferator-activated receptor-gamma (PPAR-gamma), a member of the nuclear hormone receptor superfamily, plays a critical role in adipocyte differentiation and glucose homeostasis. It has been implicated that PPAR-gamma functions as a regulator of cellular proliferation and inflammatory responses. In the present study, we examined whether troglitazone, a selective PPAR-gamma agonists, ameliorated experimental autoimmune encephalomyelitis (EAE) induced by administration of myelin oligodendrocyte glycoprotein (MOG) peptide 35-55 in C57BL/6 mice. We found that troglitazone attenuated the inflammation and decreased the clinical symptoms. It was suggested that the amelioration was attributed to the attenuation of pro-inflammatory cytokine gene expressions.

Enhanced contact hypersensitivity in human monocyte chemoattractant protein-1 transgenic mouse.

Monocyte chemoattractant protein (MCP)-1 is a chemotactic cytokine for monocytes, memoryT cells and dendritic cells (DC). However, the precise role of MCP-1 in a variety of immunological responses remains unclear. In the present study, we analyzed contact hypersensitivity (CHS) using human MCP-1 transgenic mice (hMCP-1Tgm) that constitutively produce high levels of hMCP-1 in the sera. Following 2,4-dinitrofluorobenzene (DNFB) sensitization, enhancement of CHS was demonstrated in Tgm as compared with that in non-Tgm. Anti-hMCP-1 antibodies significantly inhibited the CHS in Tgm. A prominent accumulation of B7-1+I-Ad+ Langerhans' cells (LC) bearing haptens was detected in draining lymph nodes (DLN) of Tgm 24 h after DNFB or fluorescein isothiocyanate (FITC) sensitization. Similar results were obtained with BALB/c mice administrated recombinant (r) hMCP-1. Langerhans' cells (LC) in the epidermal sheets of Tgm increased in size and expressed high levels of I-Ad and B7-1 12 h after FITC application compared with those of non-Tgm. After 18 h, the number of LC in the epidermis was reduced in Tgm. It was also shown that the B7-1 expression on LC of BALB/c mice was augmented after culture with rhMCP-1. These findings demonstrate that MCP-1 not only accelerates LC migration from epidermis into the DLN after sensitization with haptens but also up-regulates the I-Ad and B7-1 expressions, which results in the enhanced T cell activation and CHS.

Delayed clearance of zymosan-induced granuloma and depressed phagocytosis of macrophages with concomitant up-regulated kinase activities of Src-family in a human monocyte chemoattractant protein-1 transgenic mouse.

A human monocyte chemoattractant protein-1 (hMCP-1) transgenic mouse (Tgm) line which constitutively produces a large amount of hMCP-1 (7-13 ng/ml in the serum) was established. Although expression of the transgene was detected in various tissues, an accumulation of macrophages (Mphi) was seen in only lymphoid organs which might be attributed to the high concentration of hMCP-1 in these organs. A reduced phagocytosis by peritoneal Mphi in vivo and a delayed clearance of granulomas in the liver following zymosan administration were observed in these Tgm. However, peritoneal exudate cells (PEC) from Tgm exhibited normal in vitro phagocytic activity and nitric oxide (NO) production upon stimulation with IFN-gamma as compared with those from non-Tgm. In addition, high activities of src-family protein tyrosine kinases (PTK), Fgr and Hck, were also noted in the peritoneal resident cells from Tgm, whereas the level of mitogen-activated protein kinase (MAPK) activity was almost the same as that of non-Tgm. It was suggested that the low functional activities of Tgm Mphi seen in vivo were attributed to down-regulation of the unique transducing system of hMCP-1 signals under the influence of a high concentration of the hMCP-1. It seemed that the depressed functions were recovered when the peritoneal cells were released ex vivo from such a high hMCP-1 environment.

Thymic epithelial cells responsible for impaired generation of NK-T thymocytes in Alymphoplasia mutant mice.

We have previously shown that the generation of an NK1.1+TCRalphabeta+ (NK-T) cell population is severely impaired in an alymphoplasia mutant (aly/aly) mouse strain and the defect resides in the thymic environment. In the present study, to elucidate the thymic stromal component(s) that affects the development of NK-T cells, radiation bone marrow chimeras were established with the aly/aly mouse as a donor and either the beta2 microglobulin knockout (beta2m-/-) or the CD1d1-/- mouse that also lacks the NK-T cell population as a recipient. A normal population of NK-T cells with a typical NK-T phenotype and functions was detected in both the thymus and the spleen of these chimeras. These findings indicated that a radiation-resistant CD1(-) component of the thymus supported generation of functional NK-T cells from aly/aly precursors. Furthermore, transfer of an intact medullary thymic epithelial cell line into aly/aly thymus significantly induced the generation of NK-T cells in the thymus. These findings suggest that CD1 molecules of bone marrow-derived cells and the medullary epithelial cells acted in concert in the generation of the NK-T cell population and that a function(s) of the medullary thymic epithelial cells other than direct presentation of CD1 molecules to the NK-T precursors is indispensable for the development of NK-T cells.

[Immunohistochemical study of Sertoli-stromal cell tumor; comparison between the tumor arising from the gonad of a testicular feminization syndrome bearing patient and from ovaries of non-bearing patients].

The association of Sertoli-stromal cell tumor with testicular feminization syndrome (TFS) has been elaborated in the past studies. Here, we described immunohistochemical studies on Sertoli cell tumor of the gonad in a TFS patient and compare with 2 other cases of spontaneous ovarian Sertoli-stromal tumor. [Case 1] The case was a 73 year-old Japanese patient (46XY karyotype), who had had primary amenorrhea. High level of testosterone was noted in laboratory investigation (1900 ng/ml). No ambiguous morphology of external genitalia was present, but atrophy of vagina was noted. The patient was diagnosed as TFS. A left gonadal tumor was identified histologically showing well differentiated Sertoli cell tumor. The tumor cells were positive for anti-vimentin antibody but negative for anti-keratin, EMA and p53 antibodies by immunohistochemistry. The right gonad was an immature testis. [Case 2] The case was a 33 year-old female with ovarian Sertoli-Leydig cell tumor. Immunohistochemically, positive reaction for anti-keratin and p53 antibodies were observed. [Case 3] The case was a 17 year-old female with moderately differentiated Sertoli cell tumor of the ovary. The tumor cells were positive for anti-keratin, EMA and p53 antibodies by immunohistochemistry. Difference in immunohistochemical reactions between Sertoli cell tumor in TFS and Sertoli-stromal cell tumors of the ovaries was probably due to variation in the degree of gonadal development.

[Analysis of monocyte/macrophage function in a human MCAF/MCP-1 transgenic mouse].

MCAF/MCP-1 is a chemotactic cytokine which belongs to beta- or C-C chemokine subfamily. MCAF/MCP-1 activates not only monocytes but also other types of leukocytes. However, precise roles of MCAF/MCP-1 in vivo remain unclear. To elucidate these issues, we established a human MCAF/MCP-1 transgenic mouse (Tgm). The Tgm produced constitutively a high concentration of MCAF/MCP-1 (7-13 ng/ml) in the serum under the influence of beta-actin promoter in the vector of transgene. The expression of transgene was recognized in multiple organs, especially in lymphoid organs and an accumulation of macrophages was seen in these lymphoid organs. However, peritoneal macrophages of the Tgm exhibited reduced phagocytosis toward latex beads which had been injected intraperitoneally. It was also demonstrated that these Tgm had prolongation of liver granuloma reaction against the stimulation of zymosan. In contrast, activities of Fgr and Hck, macrophage-associated src-family protein tyrosine kinases, were increased in the peritoneal cells of Tgm. When peritoneal macrophages of Tgm were developed in a non-Tgm circumstance after bone marrow transplantation from Tgm into AKR, these macrophages exhibited increased expression of Mac-1. Moreover, when co-cultured with IFN-gamma, these macrophages produced a large amount of nitric oxide as compared to non-Tgm cells cultured in the same condition as Tgm cells. These findings suggested that the dysfunction of macrophages seen in human MCAF/MCP-1 Tgm in vivo was attributed to down-regulation and/or desensitization of receptors for MCAF/MCP-1 caused by the high concentration of MCAF/MCP-1.

Generation of NK1.1+ T cell antigen receptor alpha/beta+ thymocytes associated with intact thymic structure.

The development of T cells within the thymus is largely dependent on intact cortical and medullary epithelial cells. However, it has been reported that positive selection of natural killer antigen 1.1+ (NK1.1+) T cell antigen receptor (TCR)-alpha/beta+ thymocytes recently identified among CD4+8- and CD4-8- subpopulations is attributable to major histocompatibility complex class Ib ligands expressed on bone marrow (BM)-derived components in the thymus. In the present study, we investigated generation of NK1.1+ TCR-alpha/beta+ cells in the thymus of the aly/aly mouse which lacks lymph nodes and Peyer's patches and shows abnormalities of thymic and splenic structure. We found that the proportion of the NK1.1+ TCR-alpha/beta+ thymocytes was extremely low in these mice as compared with aly/+ and normal C57BL/6 mice. Thymic reconstitution by BM cells from aly/+ mice that possess a normal population of NK1.1+ TCR-alpha/beta+ cell population did not restore the NK1.1+ TCR-alpha/beta+ cell population in the thymus of lethally irradiated aly/aly mouse. When deoxyguanosine-treated fetal thymi from (B6 x B10.G)F1 mice were transplanted to aly/aly mice that had been thymectomized and reconstituted with BM cells of aly/aly mice, normal proportions of the NK1.1+ TCR-alpha/beta+ thymocytes were present in the thymus grafts. These findings demonstrate that the development of NK1.1+ TCR-alpha/beta+ thymocytes is accomplished under the influence not only of BM-derived components, but also of irradiation-resistant or deoxyguanosine-resistant components and an intact microenvironment of the thymus.

Csk overexpression reduces several monokines and nitric oxide productions but enhances prostaglandin E2 production in response to lipopolysaccharide in the macrophage cell line J774A.1.

The catalytic activity of src-family protein tyrosine kinases (src-PTK) is suppressed when a C-terminal tyrosine is phosphorylated by an intracellular PTK, C-terminal Src kinase (Csk). In the present report, to study the regulatory functions of the Csk in cells of monocyte/macrophage lineage, we transfected a eukaryotic expression vector containing rat csk cDNA in a macrophage cell line, J774A.1, and examined alterations of the response to lipopolysaccharide (LPS) in the transfectants which overexpressed Csk. Csk overexpression resulted primarily in a down-regulation of Fgr activity, an src-PTK expressed in J774A.1, and hyperphosphorylation of several cellular proteins of 35, 57, 66, 97 and 120-130 kDa. Furthermore, in these Csk transfectants, production of interleukin (IL)-1alpha, IL-6, tumor necrosis factor-alpha, and nitric oxide (NO) following LPS stimulation were reduced compared with those in parental J774A.1 or J774A.1 transfected with the vector alone. The extent of reduction paralleled the amounts of Csk proteins expressed in the Csk-transfected J774A.1. The reduced NO production in these cells was associated with low levels of mRNA of inducible NO synthetase. On the other hand, an enhancement of prostaglandin E2 production was observed in the Csk-transfected J774A.1 cells upon stimulation with LPS, which appeared to result from the high level of prostaglandin-H synthetase in the transfectants. The present findings indicate that overexpression of Csk has differential effects on the regulation of production of chemical mediators and monokines, probably via modulation of signal transduction downstream of LPS-mediated signals.

Fgr expression restricted to subpopulation of monocyte/macrophage lineage in resting conditions is induced in various hematopoietic cells after activation or transformation.

The c-fgr gene product (Fgr) is a member of the src-family of protein tyrosine kinases. We have established a monoclonal antibody (2H2) which recognizes the unique N-terminal domain of the murine Fgr. In the present study, using immunohistochemical analysis and immune complex kinase assay with the 2H2, we investigated expression of Fgr in various cell populations and tissues in a murine system. In resting conditions, Fgr expression was confined to subsets of a monocyte/macrophage lineage. Thus, Fgr+ cells were detected in paracortical areas and medullas of lymph nodes, but seen only in marginal zones of the spleen and the medulla of the thymus. No Fgr+ macrophage was detected in other tissues, Peyer's patches, brain, heart, lung, liver, pancreas, kidney and peritoneal cavity. However, immune complex kinase assay revealed that, upon stimulation, T and B cells as well as peritoneal macrophages expressed significant levels of Fgr molecules. Transformed cell lines of lymphoid origin, EL-4 and LK35.2, which are T and B lineage lymphomas, respectively, also expressed Fgr molecules. Thus, various cells of hematopoietic origin appeared to possess a potentiality to express Fgr following activation or transformation. The present findings may help elucidate the functional significance of Fgr in immunologically committed cells in either activated or non-activated conditions.