Intestinal Delivery of Proinsulin and IL-10 via Lactococcus lactis Combined With Low-Dose Anti-CD3 Restores Tolerance Outside the Window of Acute Type 1 Diabetes Diagnosis.

A combination treatment (CT) of proinsulin and IL-10 orally delivered via genetically modified Lactococcus lactis bacteria combined with low-dose anti-CD3 (aCD3) therapy successfully restores glucose homeostasis in newly diagnosed non-obese diabetic (NOD) mice. Tolerance is accompanied by the accumulation of Foxp3+ regulatory T cells (Tregs) in the pancreas. To test the potential of this therapy outside the window of acute diabetes diagnosis, we substituted autoimmune diabetic mice, with disease duration varying between 4 and 53 days, with syngeneic islets at the time of therapy initiation. Untreated islet recipients consistently showed disease recurrence after 8.2 ± 0.7 days, while 32% of aCD3-treated and 48% of CT-treated mice remained normoglycemic until 6 weeks after therapy initiation (P < 0.001 vs. untreated controls for both treatments, P < 0.05 CT vs. aCD3 therapy). However, mice that were diabetic for more than 2 weeks before treatment initiation were less efficient at maintaining normoglycemia than those treated within 2 weeks of diabetes diagnosis, particularly in the aCD3-treated group. The complete elimination of endogenous beta cell mass with alloxan at the time of diabetes diagnosis pointed toward the significance of continuous feeding of the islet antigen proinsulin at the time of aCD3 therapy for treatment success. The CT providing proinsulin protected 69% of mice, compared to 33% when an irrelevant antigen (ovalbumin) was combined with aCD3 therapy, or to 27% with aCD3 therapy alone. Sustained tolerance was accompanied with a reduction of IGRP+CD8+ autoreactive T cells and an increase in insulin-reactive (InsB12-20 or InsB13-2) Foxp3+CD4+ Tregs, with a specific accumulation of Foxp3+ Tregs around the insulin-containing islet grafts after CT with proinsulin. The combination of proinsulin and IL-10 via oral Lactococcus lactis with low-dose aCD3 therapy can restore tolerance to beta cells in autoimmune diabetic mice, also when therapy is started outside the window of acute diabetes diagnosis, providing persistence of insulin-containing islets or prolonged beta cell function.

Magnetoliposomes as Contrast Agents for Longitudinal in vivo Assessment of Transplanted Pancreatic Islets in a Diabetic Rat Model.

Magnetoliposomes (MLs) were synthesized and tested for longitudinal monitoring of transplanted pancreatic islets using magnetic resonance imaging (MRI) in rat models. The rat insulinoma cell line INS-1E and isolated pancreatic islets from outbred and inbred rats were used to optimize labeling conditions in vitro. Strong MRI contrast was generated by islets exposed to 50 µg Fe/ml for 24 hours without any increased cell death, loss of function or other signs of toxicity. In vivo experiments showed that pancreatic islets (50-1000 units) labeled with MLs were detectable for up to 6 weeks post-transplantation in the kidney subcapsular space. Islets were also monitored for two weeks following transplantation through the portal vein of the liver. Hereby, islets labeled with MLs and transplanted under the left kidney capsule were able to correct hyperglycemia and had stable MRI signals until nephrectomy. Interestingly, in vivo MRI of streptozotocin induced diabetic rats transplanted with allogeneic islets demonstrated loss of MRI contrast between 7-16 days, indicative of loss of islet structure. MLs used in this study were not only beneficial for monitoring the location of transplanted islets in vivo with high sensitivity but also reported on islet integrity and hereby indirectly on islet function and rejection.

Reversal of Diabetes in NOD Mice by Clinical-Grade Proinsulin and IL-10-Secreting Lactococcus lactis in Combination With Low-Dose Anti-CD3 Depends on the Induction of Foxp3-Positive T Cells.

The introduction of ß-cell autoantigens via the gut through Lactococcus lactis (L. lactis) has been demonstrated to be a promising approach for diabetes reversal in NOD mice. Here we show that a combination therapy of low-dose anti-CD3 with a clinical-grade self-containing L. lactis, appropriate for human application, secreting human proinsulin and interleukin-10, cured 66% of mice with new-onset diabetes, which is comparable to therapy results with plasmid-driven L. lactis Initial blood glucose concentrations (<350 mg/dL) and insulin autoantibody positivity were predictors of the stable reversal of hyperglycemia, and decline in insulin autoantibody positivity was an immune biomarker of therapeutic outcome. The assessment of the immune changes induced by the L. lactis-based therapy revealed elevated frequencies of CD4+Foxp3+ T cells in the pancreas-draining lymph nodes, pancreas, and peripheral blood of all treated mice, independent of metabolic outcome. Neutralization of cytotoxic T-lymphocyte antigen 4 and transforming growth factor-ß partially abrogated the suppressive function of therapy-induced regulatory T cells (Tregs). Ablation or functional impairment of Foxp3+ Tregs in vivo at the start or stop of therapy impaired immune tolerance, highlighting the dependence of the therapy-induced tolerance in mice with new-onset diabetes on the presence and functionality of CD4+Foxp3+ T cells. Biomarkers identified in this study can potentially be used in the future to tailor the L. lactis-based combination therapy for individual patients.

Rangelia vitalii: changes in the enzymes ALT, CK and AST during the acute phase of experimental infection in dogs.

Rangelia vitalii is a protozoon that causes diseases in dogs, and anemia is the most common laboratory finding. However, few studies on the biochemical changes in dogs infected with this protozoon exist. Thus, this study aimed to investigate the biochemical changes in dogs experimentally infected with R. vitalii, during the acute phase of the infection. For this study, 12 female dogs (aged 6-12 months and weighing between 4 and 7 kg) were used, divided in two groups. Group A was composed of healthy dogs (n = 5); and group B consisted of infected animals (n = 7). Blood samples were collected on days 0, 10, 20 and 30 after infection, using tubes without anticoagulant to obtain serum and analyze the biochemical parameters. An increase in alanine aminotransferase (ALT) on day 20 (P < 0.05) was observed. Also, increased creatine kinase (CK) and aspartate aminotransferase (AST) levels were observed throughout the experimental period (P < 0.05). No changes in the serum gamma-glutamyltransferase, urea and creatinine levels were observed. Thus, is possible to conclude that experimental infection with R. vitalii in dogs causes changes to the biochemical profile, with increased ALT, AST and CK enzyme levels.

Rangelia vitalii: changes in the enzymes ALT, CK and AST during the acute phase of experimental infection in dogs / Rangelia vitalii: mudanças nas enzimas ALT, CK e AST na fase aguda da infecção experimental em cães

Rangelia vitalii is a protozoon that causes diseases in dogs, and anemia is the most common laboratory finding. However, few studies on the biochemical changes in dogs infected with this protozoon exist. Thus, this study aimed to investigate the biochemical changes in dogs experimentally infected with R. vitalii, during the acute phase of the infection. For this study, 12 female dogs (aged 6-12 months and weighing between 4 and 7 kg) were used, divided in two groups. Group A was composed of healthy dogs (n = 5); and group B consisted of infected animals (n = 7). Blood samples were collected on days 0, 10, 20 and 30 after infection, using tubes without anticoagulant to obtain serum and analyze the biochemical parameters. An increase in alanine aminotransferase (ALT) on day 20 (P < 0.05) was observed. Also, increased creatine kinase (CK) and aspartate aminotransferase (AST) levels were observed throughout the experimental period (P < 0.05). No changes in the serum gamma-glutamyltransferase, urea and creatinine levels were observed. Thus, is possible to conclude that experimental infection with R. vitalii in dogs causes changes to the biochemical profile, with increased ALT, AST and CK enzyme levels.

Rangelia vitalii é um protozoário que causa doença em cães, sendo a anemia o achado laboratorial mais frequente. No entanto, existem poucos estudos sobre as alterações bioquímicas em cães infectados com o protozoário. Assim, este estudo tem como objetivo investigar as alterações bioquímicas de cães experimentalmente infectados com R. vitalii na fase aguda da infecção. Para o estudo, foram utilizados 12 cães fêmeas (com idade entre 6 a 12 meses e peso entre 4 a 7 kg), divididos em dois grupos. O grupo A (n = 5) foi composto de animais saudáveis e o grupo B (n = 7) de animais infectados. Amostras de sangue foram coletadas nos dias zero, dez, vinte e trinta PI, utilizando tubos sem anticoagulante para obtenção de soro e análise dos parâmetros bioquímicos. Foi observado um aumento na alanino aminotransferase (ALT) no dia 20 PI (P < 0,05) e aumento na creatinoquinase (CK) e aspartato aminotransferase (AST) em todo o período experimental (P < 0,05). Não foram observadas alterações séricas na gama-glutamiltransferase, uréia e creatinina. Portanto, é possível concluir que a infecção experimental por R. vitalii causa alterações no perfil bioquímico, com aumento na ALT, CK e AST.

Substituição dos ligamentos cruzados cranial e caudal em cães por duplo implante de polipropileno / Replacement of the cranial and caudal cruciate ligaments in dogs by double t polypropylene implant

O objetivo deste trabalho é salientar uma alternativa eficaz no tratamento da ruptura dos ligamentos cruzados cranial e caudal de cães, sem associação de imobilização externa. Foram atendidos seis animais portadores de ruptura de ambos os ligamentos cruzados. Optou-se pela correção cirúrgica intracapsular, utilizando-se dois implantes sintéticos de polipropileno, para a estabilização da articulação. Os pacientes retornaram ao apoio completo do membro em 11,8±3,5 dias e não mantiveram instabilidade articular, após 0, 30 e 90 dias de avaliação clínica pós-operatória. Aos 90 dias após a cirurgia, não se percebeu claudicação nos pacientes avaliados. Concluiu-se que a técnica utilizada promoveu total estabilidade articular na ausência dos ligamentos cruzados cranial e caudal.

The objective of this study is to point out an effective alternative in the treatment of the cranial and caudal cruciate ligaments rupture in dogs, with no association of external immobilization. Six dogs with rupture of both cruciate ligaments were included in the present study. Stifle joint was surgically stabilized by an intracapsular technique, using two polypropylene synthetic implants. The animals returned to full member support in 11.8±3.5 days and did not sustain any joint instability degree after 0, 30 and 90 days of clinical evaluation after surgery. At 90 days after surgery, it became apparent lameness in any of the six patients. It was concluded that the technique employed caused total joint stability in the absence of caudal and cranial cruciate ligaments.

Transplante de fração total de células mononucleares ou fração vascular estromal associada à membrana celulósica em feridas cutâneas experimentais de coelhos / Total fraction of mononuclear cell or stromal vascular fraction transplant associated with cellulosic membrane in experimental cutaneous wounds in rabbits

A pele apresenta diversas funções importantes para o organismo. A manutenção de sua integridade é fundamental, entre outras, para impedir a penetração de microrganismos e a perda de líquidos essenciais à manutenção da vida. Por estar constantemente exposta ao meio ambiente, a pele é altamente susceptível a traumas que podem acarretar soluções de continuidade. A cicatrização da pele ferida deve ser rápida e diversas alternativas são buscadas, visando à redução do tempo de reparo a fim de garantir cicatriz funcional e esteticamente aceitável. Uma opção cada vez mais viável para reparar tecidos danificados é a terapia celular com células-tronco adultas. Os objetivos deste trabalho consistiram em avaliar o transplante da fração total de células mononucleares (FTCM) da medula óssea (MO) e da fração vascular estromal (FVE) do tecido adiposo (TA), associado ao uso da membrana celulósica. Para realização deste experimento, 20 coelhos foram divididos aleatoriamente em quatro grupos com cinco animais cada. Após a indução da ferida cutânea experimental, o grupo A, não recebeu nenhum tratamento, o grupo B, recebeu apenas membrana celulósica e os grupos C e D, além de receberem a membrana, foram submetidos a transplante autólogo da FTCM, com valor total de células entre 6,92 x 106 a 4,91 x 107 e uma viabilidade de 82 a 97% ou da FVE, com valor total de células entre 9,6 x 105 e 6,5 x 106 e uma viabilidade de 66 a 87%, respectivamente. Ao final do período de avaliação, os três grupos tratados apresentaram diferença estatística significativa da área da ferida em relação ao grupo controle e o grupo que recebeu a FVE do tecido adiposo apresentou o menor tempo de cicatrização da ferida.

The skin presents various important functions to the organism. The maintenance of its integrity is fundamental, among others, to prevent penetration of microorganisms and exit of liquids essential to life maintenance. Due to its constant environment exposure, the skin is highly susceptible to trauma which can result solutions of continuity. The healing of wounded skin should be fast and many alternatives are searched for, aiming to reduce repair time and to guarantee a functional and esthetically acceptable scar. One option to repair injured tissues which is ever more viable is cellular therapy with adult stem cells. The aims of this study consisted in evaluating the transplant of total mononuclear cell fraction (TMCF) from bone marrow (BM) or stromal vascular fraction (SVF) from adipose tissue (AT), associated with the use of cellulose membrane. To carry out this experiment, 20 rabbits were randomly divided in four groups with five animals each. After induction of the experimental cutaneous wound, Group A did not receive any treatment; group B received only cellulose membrane; and groups C and D, in addition to receiving the membrane, were submitted to autologous transplant of TMCF, with total cell value between 6,92 x 106 and 4,91 x 107 and a viability of 82 to 97% or SVF, with total cell value between 9,6 x 105 and 6,5 x 106 and a viability of 66 a 87%, respectively. At the end of the evaluation period, the three treated groups presented significant statistical difference of wound area in relation to the control group, and the group which received SVF from adipose tissue presented the shortest wound healing time.