1.5 mJ, 6.4 fs parametric chirped-pulse amplification system at 1 kHz

We demonstrate an optical parametric chirped-pulse amplification (OPCPA) system with the pulse energy of 1.5 mJ at a 1 kHz repetition rate. The newly developed 100 ps Ti:sapphire pump laser system, which was optically synchronized with OPCPA seed pulses, delivered 10 mJ, 400 nm pump pulses. After three-stage parametric amplification, recompression of the amplifier output from 45 ps to 6.4 fs was performed. The pulse width of 6.4 fs is, to our knowledge, the shortest ever obtained by OPCPA, and the average power of 1.5 W (1.5 mJ, 1 kHz) is believed to be the highest among few-cycle OPCPA systems.

Distribution of a brain-specific extracellular matrix protein in developing and adult zebrafish

A monoclonal antibody (IgG) that recognizes a 53-kDa zebrafish brain protein was isolated and used to characterize the distribution of this protein in zebrafish. (1) The antigen was found only in the brain and not in any other tissues such as muscle, dermis and cartilage. Within the brain, the antibody recognized extracellular matrix (ECM) outside neuronal cells. (2) Digestion by hyaluronidase released the antigen from brain tissue, and the monoclonal antibody staining was also decreased by the digestion by hyaluronidase. (3) The pattern of antigen distribution is not perineuronal, as the density of the antigen at the periphery of the cells was practically identical to that of the empty intercellular spaces. Therefore, this monoclonal antibody does not recognize the perineuronal glycocortex. (4) The antigen is distributed only in limited areas of the brain, namely in the periphery of the forebrain, the hypothalamus, the optic tectum, the interpeduncular nucleus, the cerebellum and the ventricular rim of the medulla. In the optic tectum, the antibody strongly stained the most superficial layer, and in the cerebellum, it stained the molecular but not the granular layer. These patterns of distribution are very different from those of other typical brain ECM proteins and suggest that this protein may play quite distinct roles in brain development and maintenance.

Frequency-resolved optical gating of isolated attosecond pulses in the extreme ultraviolet

The pulse shape and phase of isolated attosecond extreme ultraviolet (XUV) pulses with a duration of 860 asec have been determined simultaneously by using frequency-resolved optical gating based on two-photon above-threshold ionization with 28-eV photons in He. From the detailed characterization, we succeeded in shaping isolated XUV pulses on an attosecond time scale by precise dispersion control with Ar gas density or by changing the driving pulse width. These results offer a novel way to excite and observe an electron motion in atoms and molecules.

FTY720 suppresses CD4+CD44highCD62L- effector memory T cell-mediated colitis

FTY720, a sphingosine-derived immunomodulator, causes immunosuppression via enhancement of lymphocyte sequestration into secondary lymphoid organs, thereby preventing their antigen-activated T cell egress to sites of inflammation. FTY720 is highly effective in inhibiting autoimmunity in various animal models. However, there is little known about how FTY720 controls the migration property of memory T cells. Here, we demonstrated that FTY720 prevents the development of colitis induced by the adoptive transfer of lamina propria (LP) colitogenic effector memory CD4+ T cells (TEM cells; CD45RB(low)CD44(high)CD62L-) into severe combined immunodeficiency (SCID) mice and suppresses interferon-gamma, interleukin-2, and tumor necrosis factor-alpha production by LP CD4+ T cells. The numbers of spleen, peripheral blood, mesenteric lymph node, and LP CD4+ T cells in FTY720-treated mice were significantly reduced compared with those in control mice. Notably, LP CD4+ TEM cells as well as splenic CD4+CD45RBhigh T cells expressed several spingosine-1-phosphate receptors that are targets for FTY720. Furthermore, FTY720 also prevented the development of colitis induced by the adoptive transfer of splenic CD4+CD45RBhigh T cells into SCID mice. Collectively, the present data indicate that FTY720 treatment may offer the potential not only to prevent the onset of disease but also to treat memory T cell-mediated autoimmune diseases including inflammatory bowel diseases.

Naturally arising CD4+CD25+ regulatory T cells suppress the expansion of colitogenic CD4+CD44highCD62L- effector memory T cells

Naturally arising CD4+CD25+ regulatory T (T(R)) cells have been shown to prevent and cure murine T cell-mediated colitis. However, their exact mechanism of controlling colitogenic memory CD4+ T cells in in vivo systems excluding the initial process of naive T cell activation and differentiation has not been examined to date. Using the colitogenic effector memory (T(EM)) CD4+ cell-mediated colitis model induced by adoptive transfer of colitogenic CD4+CD44(high)CD62L(-) lamina propria (LP) T cells obtained from colitic CD4+CD45RB(high) T cell-transferred mice, we have shown in the present study that CD4+CD25+ T(R) cells are able not only to suppress the development of colitis, Th1 cytokine production, and the expansion of colitogenic LP CD4+ T(EM) cells but also to expand these cells by themselves extensively in vivo. An in vitro coculture assay revealed that CD4+CD25+ T(R) cells proliferated in the presence of IL-2-producing colitogenic LP CD4+ T(EM) cells at the early time point (48 h after culture), followed by the acquisition of suppressive activity at the late time point (96 h after culture). Collectively, these data suggest the distinct timing of the IL-2-dependent expansion of CD4+CD25+ T(R) cells and the their suppressive activity on colitogenic LP CD4+ T(EM) cells.

Neuroendocrine features in poorly differentiated endometrioid adenocarcinomas of the endometrium

This study aimed to clarify neuroendocrine features (NEF) in poorly differentiated (G3) endometrioid adenocarcinoma of the endometrium and to evaluate its prognostic significance. Forty cases with G3 carcinoma were investigated for NEF immunohistochemically. The histopathologic specimens were immunostained with chromogranin A, synaptophysin, and leu-7, using the labeled streptavidin-biotin method. The staining pattern was classified into diffuse, partial, or focal. The NEF was compared with clinicopathologic variables, including patients' survival. Chromogranin A was positive diffusely in 1 patient (2.5%), partially in 8 (20%), and focally in 13 (32.5%). Synaptophysin was positive diffusely in one (2.5%), partially in three (7.5%), and focally in nine (22.5%). Leu-7 was focally positive in 10 (25%) patients. The overall positive rate of the three neuroendocrine markers was 62.5%. A patient with diffusely positive staining for both chromogranin A and synaptophysin was diagnosed with neuroendocrine carcinoma. One or more neuroendocrine markers were positive in 25 cases (62.5%). Positive NEF was correlated with clinicopathologic parameters such as stage and myometrial invasion. The survival of the patients with positive NEF, especially with positive leu-7, was significantly lower than that without NEF. NEF was detected immunohistochemically in approximately 63% of the G3 carcinomas, and these patients had a poor prognosis.

Optimal dose for stage IIIB adenocarcinoma of the uterine cervix on the basis of biological effective dose

PURPOSE

Prognosis of uterine cervical adenocarcinoma in locally advanced stage treated with radiation therapy has been considered to be much worse than that of squamous cell carcinoma because the optimal dose for the former one has not been determined. Thus, the current study was performed to investigate the optimal dose for Stage IIIB, locally advanced stage, adenocarcinoma of the uterine cervix on the basis of the biological effective dose (BED).

METHODS

One-hundred and seventy-nine patients with Stage IIIB carcinoma of the uterine cervix were treated with curative intended therapy at Kitasato University Hospital between 1976 and 2000. Out of them, 13 patients had an adenocarcinoma component in pathological findings. Nine patients were diagnosed with adenocarcinoma and four patients were diagnosed with adenosquamous cell carcinoma. All patients were treated with external radiation therapy combined with intracavitary radiation therapy. The total BED10 (T-BED10) was caluculated from the BED of the external beam radiation therapy (E-BED10) plus the BED of the intra-cavitary radiation therapy (A-BED).

RESULTS

Overall survival rate was 51%. Stratified by T-BED10 overall survival rate of the T-BED10 > or = 100 Gy group was 57% and that of the T-BED10 < 100 Gy group was 30%. There was a trend toward a better survival rate of the T-BED10 > or = 100 Gy group than the T-BED10 < 100 Gy group.

CONCLUSION

The current study suggested that the optimal dose for Stage IIIB adenocarcinoma of the uterine cervix might be T-BED10 > or = 100 Gy.

Test of the local effect model using clinical data: tumour control probability for lung tumours after treatment with carbon ion beams

The treatment planning approach used within the heavy ion tumour therapy project at GSI Darmstadt includes a biological optimisation, which is based on a biophysical model, the Local Effect Model (LEM). Here we show that the predictions of the LEM are in good agreement with clinical data obtained at the HIMAC in Chiba for the treatment of non-small-cell lung cancer, and the steep dose response for carbon ions is reproduced correctly. This steeper increase corresponds to an increasing RBE with increasing dose, which apparently is in contradiction to the systematics observed in general for in vitro measurements. A possible explanation of this discrepancy is based on the interindividual variation of photon sensitivity.

Sclerosing therapy of internal hemorrhoids with a novel sclerosing agent. Comparison with ligation and excision

BACKGROUND AND AIMS

Patients with prolapsing internal hemorrhoids were treated with a novel sclerosing agent (OC-108), and the results were compared with surgery of ligation and excision.

PATIENTS AND METHODS

This study included 20 years or older patients with prolapsing internal hemorrhoids who visited ten medical institutions in Japan from October 2000 to October 2002. Investigation on surgery was also performed.

RESULTS

Comparing OC-108 and surgery in patients with third- and fourth-degree internal hemorrhoids according to the Goligher's classification, for which surgery has been generally indicated, at 28 days after treatment, the disappearance rate of prolapse was similar between OC-108 and surgery, 94% (75/80 patients) and 99% (84/85 patients), respectively. The 1-year recurrence rate was 16% (12/73 patients) in the OC-108 group, and this value was satisfactory because of its less invasive nature while it was more or less higher compared with 2% (2/81 patients) in the surgery group. The incidences of pain and bleeding were lower in the OC-108 group.

CONCLUSIONS

OC-108 is a useful alternative treatment for hemorrhoids.

Quality of life and social role functioning in Japanese patients with panic disorder

Although a number of recent studies have shown that panic disorder is associated with deterioration in quality of life and social dysfunctions, details of these impairments and their correlates have not been well studied. The present study aims to examine which aspects of quality of life and social functioning were particularly impaired in patients with panic disorder and to search for their clinical correlates. Fifty patients with panic disorder with or without agoraphobia who participated in our group cognitive-behavioral treatment program were administered the Medical Outcomes Study Short-Form Health Survey and the Work, Home and Leisure Activities Scale. Their panic disorder symptomatology was assessed with the Panic Disorder Severity Scale and Fear Questionnaire. Compared with the population mean, the patients reported less than average quality of life in both physical and mental domains, especially in the latter domain. They also reported substantial social dysfunctions, especially in work and social leisure activities. Different aspects of patients' psychopathology were associated with these impairments. While agoraphobia appeared as a consistent predictor for most of the aspects examined, social phobia emerged as a strong predictor for mental quality of life and for work and social leisure functions. The findings suggest that we need to remain sensitive to different aspects of functional impairments of patients with panic disorder and that we may need to pay more attention to the role of social anxiety in their treatment.

Small-cell carcinoma of the uterine cervix: a clinicopathologic study of 11 cases

We report the clinical profiles and immunohistochemical features of small-cell carcinoma of the uterine cervix. Eleven cases that we have encountered at the Department of Gynecology, Kitasato University Hospital, between 1971 and 2003 are presented. Of 1370 invasive carcinomas of the uterine cervix, the incidence of small-cell carcinoma was 0.8%. Patient ages ranged between 32 and 65 years, with a mean age of 46.3 years. The clinical stages at diagnosis were Ib in four patients, IIb in three, IIIb in three, and IVb in one. All patients presented with abnormal vaginal bleeding. Two patients who are alive with no evidence of disease for 12 years and 3 years 6 months, while eight patients died of primary carcinoma between 4 and 25 months after treatment. Histopathologic findings showed solid nests with marked peripheral palisading pattern and rosette formation. Small tumor cells with scant cytoplasm demonstrated a very high nuclear/cytoplasm ratio and indistinct cell borders. The nuclei were round to oval and demonstrated increased but fine granular chromatin. Nucleoli were indistinct in all cases. Immunohistochemical findings were positive in 81.8% each for neuron-specific enolase and protein gene product 9.5, 72.7% for synaptophysin, 63.6% for chromogranin A, and 54.5% for neural cell adhesion molecule. All specimens were positive for at least one of the above. In conclusion, small-cell carcinoma of the uterine cervix revealed poor prognosis. Making an accurate diagnosis of small-cell carcinoma before performing treatment is of great significance but often difficult. Immunohistochemical analysis using several kinds of neuroendocrine markers is helpful in establishing the correct diagnosis in addition to focusing on characteristic histo- and cytopathologic features.

Small-cell carcinoma of the uterine cervix: a clinicopathologic study of 11 cases

We report the clinical profiles and immunohistochemical features of small-cell carcinoma of the uterine cervix. Eleven cases that we have encountered at the Department of Gynecology, Kitasato University Hospital, between 1971 and 2003 are presented. Of 1370 invasive carcinomas of the uterine cervix, the incidence of small-cell carcinoma was 0.8%. Patient ages ranged between 32 and 65 years, with a mean age of 46.3 years. The clinical stages at diagnosis were Ib in four patients, IIb in three, IIIb in three, and IVb in one. All patients presented with abnormal vaginal bleeding. Two patients who are alive with no evidence of disease for 12 years and 3 years 6 months, while eight patients died of primary carcinoma between 4 and 25 months after treatment. Histopathologic findings showed solid nests with marked peripheral palisading pattern and rosette formation. Small tumor cells with scant cytoplasm demonstrated a very high nuclear/cytoplasm ratio and indistinct cell borders. The nuclei were round to oval and demonstrated increased but fine granular chromatin. Nucleoli were indistinct in all cases. Immunohistochemical findings were positive in 81.8% each for neuron-specific enolase and protein gene product 9.5, 72.7% for synaptophysin, 63.6% for chromogranin A, and 54.5% for neural cell adhesion molecule. All specimens were positive for at least one of the above. In conclusion, small-cell carcinoma of the uterine cervix revealed poor prognosis. Making an accurate diagnosis of small-cell carcinoma before performing treatment is of great significance but often difficult. Immunohistochemical analysis using several kinds of neuroendocrine markers is helpful in establishing the correct diagnosis in addition to focusing on characteristic histo- and cytopathologic features

Cross-cultural evaluation of the Panic Disorder Severity Scale in Japan

The Panic Disorder Severity Scale (PDSS) [Shear et al., 1997] is rapidly gaining world-wide acceptance as a standard global severity measure of panic disorder, however, its cross-cultural validity and reliability have not been reported yet. We developed the Japanese version of the PDSS and examined its factor structure, internal consistency and inter-rater reliability and concurrent validity among Japanese patients with panic disorder with or without agoraphobia. We also established rules of thumb for interpreting PDSS total scores, taking the Clinical Global Impression severity scale as the anchoring criterion. The identical one-factor structure of the PDSS was confirmed among the Japanese patients as among the United States patients. Both internal and inter-rater reliability was excellent (Cronbach's alpha was 0.86, and ANOVA ICCs were all above 0.90). Concurrent validity of the PDSS items with self-report questionnaires tapping similar or overlapping domains was satisfactory (Pearson correlation coefficients were mostly above 0.5). Using the anchor-based approach, the following interpretative guides are suggested: among those with established panic disorder diagnosis, PDSS total scores up to 10 correspond with "mild," those between 11 and 15 with "moderate," and those at or above 16 correspond with "severe" panic disorder. The present findings support the cross-cultural generalizability of panic disorder symptomatology and of the PDSS, in particular.

The LET spectra at different penetration depths along secondary9C and11C beams

Owing to the potentially therapeutic enhancement of delayed particles in treating malignant diseases by radioactive 9C-ion beam, LET spectra at different penetration depths for a 9C beam with 5% momentum spread, produced in the secondary beam line (SBL) at HIMAC, were measured with a multi-wire parallel-plate proportional counter. To compare these LET spectra with those of a therapeutic 12C beam under similar conditions, the 12C beam was replaced with an 11C beam, yielded in the SBL as well and having almost the same range as that of the 9C beam. The LET spectra of the 9C beam and its counterpart, i.e. the 11C beam, at various depths were compared, especially around the Bragg peak regions. The results show that nearby the Bragg peak lower LET components decreased in the LET spectra of the 9C beam while extra components between the LET peak caused by the primary beam and the lower components due to the fragments could be observed. These additional contributions in the LET spectra could be attributed to parts of the emitted particles from the radioactive 9C ions with suitable conditions regarding the LET counter. Integrating these LET spectra in different manners, depth-dose and dose-averaged LET distributions were obtained for the 9C and 11C beams, forming the basic data sets for further studies. In general, the depth-dose distributions of the 9C and 11C beams are comparative, i.e. almost the same peak-to-plateau ratio. The ratio for the 9C beam, however, has room to increase due to the geometric structure limitation of the present detector. The dose-averaged LETs along the beam penetration are always lower for the 9C beam than for the 11C beam except at the falloff region beyond the Bragg peak. Applying the present depth-dose and dose-averaged LET data sets as well as the essential radiobiological parameters obtained with 12C beams previously for HSG cells, an estimate concerning the HSG cell surviving effects along the penetration of the 9C and 11C beams shows that lower survival fractions for the 9C beam at the distal part of the Bragg peak, corresponding to the stopping region of the incoming 9C ions, can be expected when the same entrance dose is given. It is still hard to appreciate the potential of 9C beams in cancer therapy based on the present LET spectrum measurement, but it provides a substantial basis for upcoming radiobiological experiments.

T-bet upregulation and subsequent interleukin 12 stimulation are essential for induction of Th1 mediated immunopathology in Crohn's disease

BACKGROUND AND AIMS

Many lines of evidence suggest that T helper cell type 1 (Th1) immune responses predominate in Crohn's disease (CD). Recently, a novel transcription factor T-box expressed in T cells (T-bet) has been reported as the master regulator of Th1 development. This study was designed to investigate the role of T-bet and proinflammatory cytokines in Th1 mediated immunopathology in CD.

MATERIALS

CD4+ lamina propria mononuclear cells (LPMCs) were isolated from surgically resected specimens (CD, n = 10; ulcerative colitis (UC), n = 10; normal controls (NL), n = 5).

METHODS

(1) T-bet expression of CD4+ LPMCs was examined by quantitative real time polymerase chain reaction and western blotting. (2) T-bet expression of LPMCs stimulated by interleukin (IL)-12/IL-18 was analysed by western blotting. (3) Interferon gamma (IFN-gamma) production and T-bet expression of CD4+ peripheral blood mononuclear cells (PBMCs) were examined with or without stimulation by anti-CD3/CD28 monoclonal antibodies and/or IL-12.

RESULTS

(1) T-bet expression of CD4+ LPMCs was increased in CD compared with UC and NL. (2) Synergistically, augmentation of IFN-gamma production by IL-12/IL-18 was independent of T-bet expression in LPMCs. (3) T-bet was induced by T cell receptor stimulation in CD4+ PBMCs. T-bet induction correlated with IFN-gamma production and with augmentation of surface expressed IL-12 receptor beta2.

CONCLUSIONS

T-bet induction by antigenic stimulation and subsequent stimulation by macrophage derived IL-12/IL-18 are important for establishing Th1 mediated immunopathology in CD.

Human intestinal epithelial cell-derived interleukin (IL)-18, along with IL-2, IL-7 and IL-15, is a potent synergistic factor for the proliferation of intraepithelial lymphocytes

Intestinal epithelial cell (IEC)-derived cytokines, such as stem cell factor (SCF), interleukin (IL)-7 and IL-15 are known to be required for the development of intestinal intraepithelial lymphocytes (IELs). A newly described cytokine, IL-18, has also been shown to be produced by intestinal epithelial cells. To demonstrate the functional effects of IL-18 on human IELs, we assessed IL-18/IL-18 receptor expression in IEC/IEL and proliferation following stimulation of intestinal IELs by IL-18. IL-18 transcripts were detected both in freshly isolated human colonic epithelial cells and in various colonic epithelial cell lines. IL-18 protein was also detected by ELISA and flow cytometric analysis using antihuman IL-18-specific monoclonal antibody (MoAb). Furthermore, IELs constitutively expressed the IL-18 receptor in addition to the IL-2 and IL-7 receptors. More importantly, IL-18 augmented significant proliferative responses of IEL in combination with IL-2, IL-7 and IL-15 both in the presence and in absence of anti-CD3 MoAb. These results suggest that IL-18 might play a crucial role in the proliferation and maintenance of intestinal IELs.

A Primary Cell Culture System for Human Cytotrophoblasts of Proximal Cytotrophoblast Cell Columns Enabling In Vitro Acquisition of the Extra-villous Phenotype

Cytotrophoblast (CT) differentiation into the extra-villous phenotype is a crucial process in initiating their invasion into the decidua and thereby developing the placenta. However, how CTs differentiate into extra-villous CTs (EVCTs) is not fully elucidated. To address this, a suitable culture model for CTs has been long-sought. But this has been hampered by annoying problems such as; cell aggregation, in vitro syncytialization, low plating efficiency, etc. The aim of this study is to develop a culture system in which CTs differentiate into EVCTs. CTs were isolated from the first trimester placenta using density gradient separation and immuno-depletion using anti-CD9 antibody to remove contaminating fibroblasts and EVCTs. The resultant isolated CTs were found to have the character similar to poorly differentiated CTs comprising proximal cytotrophoblastic cell columns as confirmed by immunocytochemical and flowcytometric analyses. When cultured on type 4 collagen-coated plates in culture media containing low calcium concentration, CTs neither aggregated nor syncytialized, remaining mononuclear and monolayer state. Interestingly, cultured CTs gradually upregulated integrin alpha1, CD9, and human leukocyte antigen (HLA)-G; the known markers specific for EVCTs invading into the decidua diffusely. Hence, the CT culture system provides a sophisticated experimental model in which highly purified CTs acquire the extra-villous phenotype without syncytialization.

Normal development of the gut-associated lymphoid tissue except Peyer's patch in MyD88-deficient mice

MyD88 is a key adaptor molecule for signalling via Toll-like receptors (TLRs) and the response to gut commensal microbes. To investigate the role of TLRs/MyD88 pathway in the development of the gut-associated lymphoid tissue (GALT), we examined the development of Peyer's patches (PPs) and cryptopatch (CP), and also one of effector compartment, intraepithelial lymphocyte (IEL) in MyD88-/-, TLR2-/- and TLR4-/- mice. In MyD88-/- mice, the organogenesis of PPs was not disturbed. However, PPs in 2-week-old MyD88-/- mice were significantly smaller than those in MyD88+/- mice. Also, in 2-week-old TLR4-/-, but not TLR2-/- mice, PPs did not develop rapidly. The development of PPs in MyD88-/- and TLR4-/- mice was completely recovered in 10 weeks. PP cells from MyD88-/- mice showed significant decrease in proliferation when stimulated with lipopolysaccharide. The development of CP and IEL was also normal in 10-week-old MyD88-/- mice. These results suggest that the TLRs/MyD88 pathway might be involved in the development of PPs only at early postnatal stage, and TLRs/MyD88-independent signalling is critically involved in the development of GALT in adult mice.

Chromosomal aberrations induced by high-energy iron ions with shielding

Biophysical models are commonly used to evaluate the effectiveness of shielding in reducing the biological damage caused by cosmic radiation in space flights. To improve and validate these codes biophysical experiments are needed. We have measured the induction of chromosomal aberrations in human peripheral blood lymphocytes exposed in vitro to 500 MeV/n iron ion beams (dose range 0.1-1 Gy) after traversing shields of different material (lucite, aluminium, or lead) and thickness (0-11.3 g/cm2). For comparison, cells were exposed to 200 MeV/n iron ions and to X-rays. Chromosomes were prematurely condensed by a phosphatase inhibitor (calyculin A) to avoid cell-cycle selection produced by the exposure to high-LET heavy-ion beams. Aberrations were scored in chromosomes 1, 2, and 4 following fluorescence in situ hybridization. The fraction of aberrant lymphocytes has been evaluated as a function of the dose at the sample position, and of the fluence of primary 56Fe ions hitting the shield. The influence of shield thickness on the action cross-section for the induction of exchange-type aberrations has been analyzed, and the dose average-LET measured as a function of the shield thickness. These preliminary results prove that the effectiveness of heavy ions is modified by shielding, and the biological damage is dependent upon shield thickness and material.

Ameliorating effect of anti-Fas ligand MAb on wasting disease in murine model of chronic colitis

Fas/Fas ligand (FasL) interaction has been implicated in the pathogenesis of various diseases. To clarify the involvement of Fas/FasL in the pathogenesis of intestinal inflammation, we investigated the preventive and therapeutic effects of neutralizing anti-FasL monoclonal antibody (MAb) on the development of chronic colitis induced by adaptive transfer of CD4+CD45RBhigh T cells to SCID mice. Administration of anti-FasL MAb from 1 day after T cell transfer (prevention study) resulted in a significant improvement of clinical manifestations such as wasting and diarrhea. However, histological examination showed that mucosal inflammation in the colon, such as infiltration of T cells and macrophages, was not improved by the anti-FasL MAb treatment. In vitro studies showed that anti-FasL MAb did not inhibit IFN-gamma production by anti-CD3/CD28-stimulated lamina propria CD4+ T cells but suppressed TNF-alpha and IL-1beta production by lamina propria mononuclear cells. Therapeutic administration of anti-FasL MAb from 3 wk after T cell transfer also improved ongoing wasting disease but not intestinal inflammation. These results suggest that the Fas/FasL interaction plays a critical role in regulating systemic wasting disease but not local intestinal inflammation.