Cellular senescence promotes meibomian gland dysfunction in a chronic graft-versus-host disease mouse model.

PURPOSE: Aging is a well-established risk factor for meibomian gland dysfunction (MGD). We previously reported an accelerated cellular senescence phenomenon in the lacrimal glands of a murine model of chronic graft-versus-host disease (cGVHD). Herein, we aimed to elucidate the relationship between cellular senescence and MGD in cGVHD mice, utilizing the senolytic agent ABT-263. METHODS: A cGVHD mouse model was established through allogeneic bone marrow transplantation (BMT) from B10.D2 to BALB/c mice. Subsequently, cGVHD mice were treated with either ABT-263 or vehicle. The eyelids of recipients were analyzed at 4-week intervals post-BMT in both groups. RESULTS: Meibomian gland (MG) area was significantly smaller in cGVHD mice than in syngeneic control mice. ABT-263-treated mice retained a significantly larger MG area than their vehicle-treated counterparts. Pathological and immunohistochemical examinations revealed significant reductions in eyelid tissue inflammation and pathological fibrosis in the ABT-263 group compared to that in the vehicle-treated group. Additionally, expression of DNA damage markers, senescent cell markers, and senescence-associated secretory phenotype (SASP) factors was elevated in the eyelids of cGVHD mice compared with that in syngeneic mice. The expression of these cellular senescence-associated molecules was considerably suppressed in ABT-263-treated eyelids compared to that in vehicle-treated ones. CONCLUSIONS: Cellular senescence, along with expression of SASP factors, exhibited increased activity in the eyelids, particularly in the MGs of cGVHD mice. ABT-263 mitigated the severity of MGD. These findings highlight the potential of targeting cellular senescence as an effective approach for MGD treatment in cGVHD.

Effects of Substitution on Cytotoxicity of Diphenyl Ditelluride in Cultured Vascular Endothelial Cells.

Among organic-inorganic hybrid molecules consisting of organic structure(s) and metal(s), only few studies are available on the cytotoxicity of nucleophilic molecules. In the present study, we investigated the cytotoxicity of a nucleophilic organotellurium compound, diphenyl ditelluride (DPDTe), using a cell culture system. DPDTe exhibited strong cytotoxicity against vascular endothelial cells and fibroblasts along with high intracellular accumulation but showed no cytotoxicity and had less accumulation in vascular smooth muscle cells and renal epithelial cells. The cytotoxicity of DPDTe decreased when intramolecular tellurium atoms were replaced with selenium or sulfur atoms. Electronic state analysis revealed that the electron density between tellurium atoms in DPDTe was much lower than those between selenium atoms of diphenyl diselenide and sulfur atoms of diphenyl disulfide. Moreover, diphenyl telluride did not accumulate and exhibit cytotoxicity. The cytotoxicity of DPDTe was also affected by substitution. p-Dimethoxy-DPDTe showed higher cytotoxicity, but p-dichloro-DPDTe and p-methyl-DPDTe showed lower cytotoxicity than that of DPDTe. The subcellular distribution of the compounds revealed that the compounds with stronger cytotoxicity showed higher accumulation rates in the mitochondria. Our findings suggest that the electronic state of tellurium atoms in DPDTe play an important role in accumulation and distribution of DPDTe in cultured cells. The present study supports the hypothesis that nucleophilic organometallic compounds, as well as electrophilic organometallic compounds, exhibit cytotoxicity by particular mechanisms.

A case of mitral valve repair complicated by acquired factor V deficiency.

Factor V deficiency is an extremely rare hematologic disorder with an incidence of one in one million. However, the risks related to cardiac surgery employing cardiopulmonary bypass in patients with factor V deficiency are not well established. Herein, we report the case of a 71-year-old male who was incidentally diagnosed with acquired factor V deficiency underwent mitral valve repair for severe mitral regurgitation. The patient was treated preoperatively with an adrenocorticosteroid immunosuppressant therapy; the procedure was performed safely with a positive outcome.

Associated factors of poor treatment outcomes in patients with giant cell arteritis: clinical implication of large vessel lesions.

BACKGROUND: Relapses frequently occur in giant cell arteritis (GCA), and long-term glucocorticoid therapy is required. The identification of associated factors with poor treatment outcomes is important to decide the treatment algorithm of GCA. METHODS: We enrolled 139 newly diagnosed GCA patients treated with glucocorticoids between 2007 and 2014 in a retrospective, multi-center registry. Patients were diagnosed with temporal artery biopsy, 1990 American College of Rheumatology classification criteria, or large vessel lesions (LVLs) detected by imaging based on the modified classification criteria. Poor treatment outcomes (non-achievement of clinical remission by week 24 or relapse during 52 weeks) were evaluated. Clinical remission was defined as the absence of clinical signs and symptoms in cranial and large vessel areas, polymyalgia rheumatica (PMR), and elevation of C-reactive protein (CRP) levels. A patient was determined to have a relapse if he/she had either one of the signs and symptoms that newly appeared or worsened after achieving clinical remission. Re-elevation of CRP without clinical manifestations was considered as a relapse if other causes such as infection were excluded and the treatment was intensified. Associated factors with poor treatment outcomes were analyzed by using the Cox proportional hazard model. RESULTS: Cranial lesions, PMR, and LVLs were detected in 77.7%, 41.7%, and 52.5% of the enrolled patients, respectively. Treatment outcomes were evaluated in 119 newly diagnosed patients who were observed for 24 weeks or longer. The mean initial dose of prednisolone was 0.76 mg/kg/day, and 29.4% received any concomitant immunosuppressive drugs at baseline. Overall, 41 (34.5%) of the 119 patients had poor treatment outcomes; 13 did not achieve clinical remission by week 24, and 28 had a relapse after achieving clinical remission. Cumulative rates of the events of poor treatment outcomes in patients with and without LVLs were 47.5% and 17.7%, respectively. A multivariable model showed the presence of LVLs at baseline was significantly associated with poor treatment outcomes (adjusted hazard ratio [HR] 3.54, 95% CI 1.52-8.24, p = 0.003). Cranial lesions and PMR did not increase the risk of poor treatment outcomes. CONCLUSION: The initial treatment intensity in the treatment algorithm of GCA could be determined based upon the presence or absence of LVLs detected by imaging at baseline.

High plasma mycophenolate acid concentration in the early phase of induction therapy predicts good renal outcome in lupus nephritis.

Objectives: To identify the prognostic predictive factor of complete renal response (CR) at week 12 by focusing on the plasma mycophenolic acid (MPA) concentration in induction therapy in lupus nephritis.Methods: We prospectively enrolled patients with biopsy-proven LN class III/IV who were hospitalized between 2016 and 2017. As an induction therapy, mycophenolate mofetil was continuously introduced at 2000 mg/day. We measured the MPA plasma concentration at two time points depending on the induction therapy phase, early (week 4) or middle (week 12). The association between these concentrations and CR rate at week 12 was evaluated.Results: Ten patients were enrolled. A significantly higher AUC0-12 between 0 and 12 h of MPA at the early phase was observed in the patients with CR at week 12 than in those without (p = .03). All the patients with high MPA-AUC0-12 (> 40 mg h/L) at the early phase achieved CR at week 12, but no such association was found at the middle phase. The multivariate analysis revealed that MPA-AUC0-12 was selected as an independent predictive factor of CR at week 12 (odds ratio: 1.12; 95% confidence interval: 1.01-1.45, p = .02).Conclusion: The high AUC0-12 of MPA at the early phase of induction therapy may predict good renal response.

New simple and quick method to analyze serum variant transthyretins: direct MALDI method for the screening of hereditary transthyretin amyloidosis.

BACKGROUND: Hereditary transthyretin amyloidosis (ATTRv amyloidosis) is caused by a variant transthyretin (TTR), which is a serum protein secreted by the liver. Mass spectrometry (MS) is a useful tool that can detect variant TTRs in serum samples from patients with ATTRv amyloidosis. We previously reported several mass spectrometric methods to detect variant TTRs in serum samples. Those methods require cumbersome immunoprecipitation with anti-TTR antibodies and significant time to analyze the variant TTRs. In our study here, we developed a new simple and quick method to detect variant TTRs in serum samples by means of matrix-assisted laser desorption-ionization time-of-flight (MALDI-TOF) MS without immunoprecipitation (direct MALDI). METHODS: By using direct MALDI, we analyzed 288 serum samples obtained from patients who were clinically suspected having amyloidosis to investigate the usefulness of this direct MALDI method to detect variant TTRs in serum samples. RESULTS: The method completed the process within 30 min. We successfully identified variant TTRs in serum samples from patients, except for a few patients with TTR Glu61Lys and Glu89Gln mutations because of the small mass shift of those variant TTRs from wild-type TTR. We also found that the mass shifts of variant TTRs measured by direct MALDI corresponded to theoretical mass changes. CONCLUSION: Our results suggest that the direct MALDI method is useful for the screening of ATTRv amyloidosis.

Renal protective effect of antiplatelet therapy in antiphospholipid antibody-positive lupus nephritis patients without antiphospholipid syndrome.

OBJECTIVE: We sought to evaluate the effect of antiplatelet therapy in addition to conventional immunosuppressive therapy for lupus nephritis (LN) patients positive for antiphospholipid antibodies (aPL) without definite antiphospholipid syndrome (APS). METHODS: Patients with biopsy-proven LN class III or IV were retrospectively evaluated. We selected patients positive for anticardiolipin antibody (aCL) or lupus anticoagulant (LA) who did not meet the criteria for a diagnosis of APS. The patients were divided into two subgroups according to whether antiplatelet therapy was received. The cumulative complete renal response (CR) rate, relapse-free rate, and change in estimated glomerular filtration rate (eGFR) over 3 years after induction therapy were calculated. RESULTS: We identified 17 patients who received antiplatelet therapy and 21 who did not. Baseline clinicopathological characteristics and immunosuppressive therapy did not show a significant difference between the two groups except for a higher incidence of LN class IV in the treatment group (p = 0.03). There was no difference in cumulative CR rate, relapse-free rate, or eGFR change between these subgroups. However, when data on LA-positive patients were assessed, an improvement in eGFR was found (p = 0.04) in patients receiving antiplatelet treatment. CONCLUSION: Addition of anti-platelet therapy was associated with an improvement of eGFR in LA-positive patients with LN class III or IV.

Combined disease with pulmonary arterial hypertension and pulmonary venous hypertension revealed after treatment of heart failure with preserved ejection fraction in a case with primary Sjögren syndrome.

A 49-year-old woman with primary Sjögren syndrome initially developed pulmonary venous hypertension (PVH) due to heart failure with preserved ejection fraction. Endomyocardial biopsy specimens showed mild myocardial fibrosis. Pulmonary arterial hypertension (PAH) was revealed after the treatment with diuretics. During the treatment for PAH using upfront combination with pulmonary vasodilators and immunosuppressants, the patient developed combined disease with PAH and PVH. A careful hemodynamic assessment is necessary in such cases.

Rhabdomyolysis in a Patient with Polyarteritis Nodosa.

Polyarteritis nodosa (PAN) is a medium vessel vasculitis affecting systemic organs. Muscle involvement of PAN usually lacks elevation of creatinine kinase (CK). We herein report a case of PAN with rhabdomyolysis. A 71-year-old man was hospitalized because of muscle weakness of the lower limbs that persisted for 1 month. On a physical examination, rapidly progressive lower proximal muscle weakness and bilateral drop foot were observed. His blood test showed an elevation in the C-reactive protein (19.5 mg/dL) and CK (13,435 IU/L) levels and negativity for anti-neutrophilic cytoplasmic antibody. Computed tomographic angiography showed stenosis of the left renal artery. Electromyogram indicated mono-neuritis multiplex pattern, and enhanced magnetic resonance imaging demonstrated discretely granular hyperintensities on T2 and slow tau inversion recovery in his femoral muscles. A femoral muscle-biopsy specimen showed fibrinoid necrosis of medium-sized vessels and disruption of the elastic lamina of the vessel wall in fascia. Furthermore, muscle necrosis was localized depending on the arterial distribution, suggesting ischemic changes in the muscles. Given these findings, he was diagnosed with PAN with rhabdomyolysis and treated with methyl-prednisolone pulse therapy followed by oral prednisolone at 50 mg/day. He was additionally treated with monthly intravenous cyclophosphamide at 500 mg. Sustained remission has been obtained for two months since the treatment. Although rhabdomyolysis rarely manifests with PAN, it should be included in a differential diagnosis of febrile patients presenting with acute myalgia and weakness with CK elevation.

T cells upon activation promote endothelin 1 production in monocytes via IFN-γ and TNF-α.

Endothelin 1 (ET-1), mainly produced from vascular endothelial cells, induces vasoconstriction in physiological conditions. The endothelin receptor antagonist is among the most effective agents for pulmonary hypertension. However, little is known about the production source of ET-1 in inflammation and immunity. Here, we studied whether T cell-mediated ET-1 production system exists and operates independent of the production system in vascular endothelial cells. ET-1 production was readily detectable in the culture supernatant of human PBMCs and murine spleen cells stimulated with anti-CD3 antibody. Immunocytostaining showed that ET-1-producing cells emerged only in PBMCs stimulated with anti-CD3 antibody. Using the Transwell system, both murine and human monocytes sorted with magnetic beads in the inner chamber produced ET-1 when T cells were activated with antigen or anti-CD3 antibody in the outer chamber. This ET-1 production was inhibited by anti-IFN-γ and/or TNF-α antibody. Furthermore, monocytes purified from ETflox/flox;Tie2-Cre( + ) mice, which conditionally lack ET-1 in hematopoietic stem cells and vascular endothelial cells, did not produce ET-1 even when stimulated by antigen-specific T cell activation. This study demonstrates the existence of an immune-mediated ET-1 production induced by T cells upon activation through IFN-γ and TNF-α.

Comparison of renal response to four different induction therapies in Japanese patients with lupus nephritis class III or IV: A single-centre retrospective study.

The recent recommendations for the management of lupus nephritis suggest that racial background should be considered while choosing induction therapy. However, the responses to different induction regimens have been poorly studied in Japanese population. Here, we assessed the renal response to different induction therapies in Japanese patients with lupus nephritis class III or IV. The records of 64 patients with biopsy-proven lupus nephritis class III or IV were retrospectively evaluated according to therapy received: monthly intravenous cyclophosphamide (IVCY), the Euro-lupus nephritis trial (ELNT) protocol-IVCY, tacrolimus (TAC), or mycophenolate mofetil (MMF). We investigated cumulative complete renal response (CR) rates and relapse rates for each group for 3 years. Organ damage was assessed with the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI). There were 22 patients on monthly IVCY, 18 on ELNT-IVCY, 13 on TAC, and 11 on MMF. Lower systemic lupus erythematosus disease activity index (SLEDAI) and higher CH50 were found in the TAC group at baseline (p<0.01 and p<0.01, respectively). There were no significant differences of cumulative CR rates and relapse free survival for 3 years among the four different therapeutic regimens (p = 0.2 and p = 0.2, respectively). There was a tendency to have early response and early relapse in TAC group and late response in MMF group. The SDI increase over 3 years was found more frequently in the TAC group than in the monthly-IVCY group (p = 0.04). Multivariate analysis indicated that CR at 3 months was independent prognosticator for low damage accrual. Regarding lower damage accrual, early CR achievement might be essential in induction therapy regardless of immunosuppressant choice.

Lack of partial renal response by 12 weeks after induction therapy predicts poor renal response and systemic damage accrual in lupus nephritis class III or IV.

BACKGROUND: Lupus nephritis class III or IV is associated with a poor prognosis for both patient and renal survival. Recommendations for the management of lupus nephritis have recently been established, and changing therapies is recommended for patients who do not respond adequately to induction therapy. However, it remains a major challenge to determine when to switch the treatment. In this study, we identified early prognostic factors capable of predicting poor renal outcome as well as overall damage accrual in patients with lupus nephritis class III or IV. METHODS: Eighty patients with biopsy-proven lupus nephritis class III or IV were retrospectively recruited and divided into two groups: those with complete renal response (CR) or non-CR at 3 years after induction therapy. We investigated when clinical responses were obtained at each observational period from baseline to year 3. Clinical responses were divided into three groups: CR, partial renal response (PR), and non-PR. Furthermore, patients were assessed using the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI) and cumulative dose of corticosteroid for 3 years. RESULTS: Forty-four patients with CR and thirty-six with non-CR were enrolled. The cumulative CR rate was 85.0%. PR rates of patients with CR were significantly higher than those with non-CR from week 12 (p < 0.01). We identified the achievement of PR at 12 weeks as an independent predictor (OR 3.57, p = 0.03) by multivariate analysis. We next divided all patients into two groups according to PR achievement at week 12. The cumulative CR rate of the patients who achieved PR at week 12 was significantly higher than that of those who did not (96.5% vs 69.2%, p < 0.001). Furthermore, a significantly higher SDI and cumulative dose of corticosteroid were seen in the patients who did not achieve PR at week 12 than in those who did, regardless of their CR status, at year 3. CONCLUSIONS: Lack of PR at week 12 predicts a lower likelihood of achieving CR at 3 years and a higher SDI.

Changes in pathological and biochemical findings of systemic tissue sites in familial amyloid polyneuropathy more than 10†years after liver transplantation.

OBJECTIVE: To elucidate the long-term effects of liver transplantation (LT) on familial amyloid polyneuropathy (FAP). METHODS: We investigated clinicopathological and biochemical characteristics of systemic tissues in four autopsied cases of FAP patients surviving more than 10 years after LT and seven autopsied cases without LT. For analysing the truncated form of transthyretin (TTR) in amyloid, we also employed specimens from additional 18 FAP patients. RESULTS: Several tissue sites such as the heart, tongue and spinal cord had moderate-to-severe amyloid deposits but other tissues showed no or mild amyloid deposition. Those findings seemed similar to those observed in senile systemic amyloidosis (SSA), a sporadic amyloidosis caused by wild-type (WT) TTR. Also, amyloid deposits in systemic tissue sites except for the spinal cord in patients after LT derived mostly from WT TTR secreted from the normal liver grafts. In addition, in non-transplantation patients, proportions of WT TTR seemed to be relatively high in those tissue sites in which patients after LT had severe amyloid deposition, which suggests that WT TTR tends to form amyloid in those tissue sites. Finally, although the truncation of TTR in amyloid deposits did not depend on undergoing LT, we elucidated the truncation of TTR occurred predominantly in patients from non-endemic areas of Japan, where FAP amyloidogenic TTR V30M patients are late onset and low penetrance, compared with patients from an endemic area of Japan. CONCLUSIONS: FAP may shift to systemic WT TTR amyloid formation after LT, which seems to be similar to the process in SSA. The truncation of TTR in amyloid deposits may depend on some genetic or environmental factors other than undergoing LT.

Advantage of higher-avidity CTL specific for Tax against human T-lymphotropic virus-1 infected cells and tumors.

Strong CTL response can be observed and associated with the control of proviral load in human T-lymphotropic virus type 1 (HTLV-1) infection. However, there are few details with regard to how HTLV-1 specific CTLs work against HTLV-1 infected cells and adult T-cell leukemia cells (ATLs). In this study, using Tax-specific CTL lines with high- and low-functional avidity developed from HLA-A2-transgenic mice, we showed that higher avidity CTLs specific for Tax expressing larger numbers of TCRs and better binding strength to the antigen-HLA-A2 complex are much more efficient at eliminating HTLV-1 infected cells and, in particular, ATL tumor cells with the ability of recognizing a latent level of Tax product detected only with a real-time PCR. These findings suggest that such higher avidity CTLs specific for Tax in HTLV-1 could be responsible for preventing the development of HTLV-1 infection by detecting trace amount of antigens.

Immunosuppressive effect of angiotensin receptor blocker on stimulation of mice CTLs by angiotensin II.

While angiotensin II, which is produced by the renin-angiotensin-aldosterone system, is considered to be the major regulator molecule that controls both the blood pressure and fluid system, there is an increasing body of evidence that this bioactive peptide and its receptor might also contribute to the immune system. However, there are few details known about the direct effect that angiotensin type I receptors (AT1R) have on the cytotoxic T cell (CTL). To clarify the relationship between angiotensin II and its CTL receptor, we used murine splenic and antigen-specific CTLs. Murine CTLs constantly expressed AT1R, with the activation of the AT1R expression strengthened by both anti-CD3 Ab and the use of an antigen-specific methodology. Moreover, the production of IFN-gamma and TNF-alpha through CTL stimulation can be inhibited by the selective AT1R inhibitor, Losartan. In particular, the TNF-alpha production from activated CTL that had been magnified by angiotensin II, was nullified by the AT1R inhibitor. However, a cytotoxic assay indicated it did not have any effect on the cognate interaction of the CTLs. In addition, the antigen-specific CTL induction by immunization with the CTL antigenic peptide was reduced by angiotensin II type 1 receptor blocker (ARB) in vivo. These findings suggest that ARBs might have the ability to suppress excessive antigen-specific activation and induction of CTLs promoted by angiotensin II.

[A case of chronic graft-versus-host disease presenting with polymyositis].

Polymyositis is an uncommon manifestation as a complication of chronic graft-versus-host disease (GVHD). We report a case of a 55 years' old woman diagnosed as polymyositis 2 years after bone marrow transplantation against T-cell lymphoma. Muscle weakness and the elevation of CPK value were compatible with pathognomonic findings of polymyositis. However, the muscle weakness was distributed particularly into distal lower extremities and neck. It is different from that of the typical findings in autoimmune polymyositis. Histological findings showed atrophy and anisocytosis of muscles without invasion of mononuclear cells. This might be a case of GVHD-induced polymyositis occurring symptomatically after substantially progressing under the treatment with immunosuppressive agents to control chronic GVHD after bone marrow transplantation. The treatment with prednisone (1 mg/kg) brought the rapid improvement of muscle weakness and CPK value as well as mouth dryness and cholestatic liver dysfunction like in primary biliary cirrhosis. Moreover, dose up of cyclosporine and addition of mizolibine allowed for the use of lower dose of prednisone. This case suggested that the mononuclear cells invasion into muscles in a chronic GVHD patient could not always be a definitive finding of chronic GVHD-associated polymyositis because of prior use of immunosuppressive agents.

Clinical and histopathologic features of 8 patients with microscopic polyangiitis including two with a slowly progressive clinical course.

BACKGROUND: Microscopic polyangiitis (MPA) is a systemic antineutrophil cytoplasmic autoantibody-associated vasculitis associated with necrotizing and crescentic glomerulonephritis and pulmonary capillaritis. MPA generally has a rapidly progressive clinical course, but there have been recent reports of slowly progressive cases. OBJECTIVE: To evaluate the typical cutaneous findings of MPA, we recorded the clinical and histopathologic features of the cutaneous manifestations. METHODS: Eight patients with MPA, who had presented with cutaneous manifestations between 2001 and 2005 in our department, were retrospectively reviewed. They had necrotizing vasculitis in their cutaneous lesions as confirmed by skin biopsy specimens. Patients with other known connective tissue diseases were not included in the study. RESULTS: All 8 patients with MPA presented cutaneously with erythematous macules on their extremities. Livedo reticularis (5/8, 68%) was also observed. Six of the 8 patients with MPA were given the diagnosis within 3 months of their initial manifestation. In skin biopsy specimens, necrotizing vasculitis was noted in the reticular dermis to the subcutaneous fat. In contrast, the other two patients with MPA were given the diagnosis about 10 years after their initial manifestation. Histopathologic findings demonstrated necrotizing vasculitis with moderate neutrophilic infiltrations in the papillary to middle dermis in the latter two patients. Serum myeloperoxidase-antineutrophil cytoplasmic autoantibody levels were only moderlately elevated in the latter two patients and they were given the diagnosis of slowly progressive MPA. Histopathologically, palisading granulomas were present on the elbow of one of them. LIMITATIONS: The study was based on histopathological analysis in a limited number of patients due to the rareness of the investigated disease. CONCLUSIONS: There appears to be a correlation between a slowly progressive clinical course of MPA and the depth of dermal involvement and the severity of neutrophilic infiltration in biopsy specimens. Based on these results, we believe that these characteristic patterns may help clinicians establish an earlier diagnosis of possible MPA with positive antineutrophil cytoplasmic autoantibody titers.

[A case of colonic obstruction due to post-operative stenosis of the colon and multiple enteroliths].

An 81-year-old man who had under gone two abdominal surgeries and temporary colostomy 30 years previously was admitted due to lower abdominal pain and vomiting. An abdominal X-ray film and abdominal CT scan showed intestinal distension and multiple calcareous deposits in the colon. Gastrografin enema examination revealed smooth stenosis at the sigmoid colon and many additional defects. Endoscopy could not be performed due to the stenosis. He did not agree to surgery. Seven months later, he was admitted again, due to colonic obstruction. Surgery was performed which revealed colonic obstruction as the source of post-operative stenosis of the sigmoid colon and multiple enteroliths. The stones consisted of a core and a hull and contained ammonium magnesium phosphate.

Possible therapeutic vaccine strategy against human immunodeficiency virus escape from reverse transcriptase inhibitors studied in HLA-A2 transgenic mice.

Mutation of human immunodeficiency virus (HIV) leading to escape from anti-HIV drugs is the greatest challenge to the treatment of HIV infection. High-grade resistance to the nucleoside reverse transcriptase (RT) inhibitor lamivudine (also known as 3TC) is associated with a substitution of valine for methionine at position 184 of RT. This amino acid residue is contained within the HLA-A2-restricted epitope VIYQYMDDL (RT-WT). Here, we sought to determine whether a peptide vaccine could be developed using an epitope enhancement strategy that could induce a cytotoxic T-lymphocyte (CTL) response specific for an epitope containing the drug resistance mutation M184V to exert an opposing selective pressure. RT-WT-specific CTLs developed from HLA-A2 transgenic mice did not recognize the M184V mutation of RT-WT (RT-M184V). However, RT-M184V exhibited higher binding affinity for HLA-A2 than RT-WT. Also, both anchor-enhanced RT-WT (RT-2L9V) and RT-2L9V-M184V-specific CTLs recognized RT-M184V and displayed cross-reactivity to RT-WT. Nevertheless, the CTL repertoire elicited by the epitope-enhanced RT-2L9V-M184V appeared more selective for the RT inhibitor-induced M184V mutation. Peptide vaccines based on such strategies may be worth testing for their ability to exert selective pressure against drug-resistant strains and thus delay or prevent the development of HIV with the M184V resistance mutation.