Combined administration routes of marine yeasts enhanced immune-related genes and protection of white shrimp (Penaeus vannamei) against Vibrio parahaemolyticus.

Antibiotic usage to control infectious diseases in shrimp aquaculture has led to serious problems on antimicrobial resistance. An alternative to mitigate this issue is the use of probiotics, which can be easily administered by feed and water. This study examines immunomodulatory and protective effects of the marine yeasts Debaryomyces hansenii CBS8339 (Dh) and Yarrowia lipolytica Yl-N6 (Yl) -alone and mixed-in white shrimp Penaeus vannamei post-larvae. Administration routes (fed and water alone or in combination), supplementation frequency and time elapsed after the last dietary supplement were tested on growth and gene expression of penaeidin, lectin, lysozyme, superoxide dismutase, catalase, and peroxidase, as well as survival upon Vibrio parahaemolyticus IPNGS16 challenge. Penaeidin and lectin genes were upregulated in post-larvae fed orally with Yl or combined Dh + Yl. Higher growth and survival for yeast supplementation treatments were observed compared to the control group, mainly when yeasts (Dh + Yl) and administration routes (feed and water) were combined. In conclusion, mixed yeast and combined administration routes improved growth and immunity against V. parahaemolyticus.

Cellular immunity in patients with leprosy. Circulating T lymphocytes and their response to PHA in leprosy.

The ability of peripheral blood lymphocytes from polar lepromatous (LL), borderline lepromatous (BL) and borderline tuberculoid (BT) patients to transform in vitro in the presence of phytohemagglutinin was found to be significantly reduced. A significant reduction in the percentage and absolute number of T lymphocytes was observed in LL cases. In BL cases the number of T lymphocytes was decreased, but the reduction was proportional to the reduction in the total lymphocyte population was observed only in bacteriologically positive cases.

Lymphocyte transformation test in leprosy; correlation of the response with inflammation of lesions.

Lymphocyte transformation tests (LTT) using 'whole washed" and 'sonicated" preparations of Mycobacterium leprae (M. leprae) as antigen were studied in eighty-one patients with borderline leprosy. The results were correlated with the histological and the clinical pictures. There was a good correlation with the histological spectrum, LTT responses generally being higher in the borderline tuberculoid leprosy patients and lower in the borderline lepromatous. However, considerable variation was noted in each group of the borderline leprosy spectrum, and it was found that this was due in part to the degree of inflammation in the skin. Thus those with 'inflamed" skin lesions had higher responses than those with 'silent" lesions, and even those with borderline lepromatous leprosy with inflamed lesions had higher responses than those with borderline tuberculoid leprosy whose lesions were silent. Those who had reversal reactions, where inflammation is very marked, had very high LTT responses which fell with treatment of the reaction with steroids. It thus appears that the LTT in leprosy is influenced by the occurrence of hypersensitivity reactions as well as by the patient's ability to resist bacillary multiplication.

Immunological characteristics of the armadillo, Dasypus sabanicola.

The immunological responses of the armadillo are of interest because of its susceptibility to generalized lepromatoid infection with Mycobacterium leprae. In this study, specimens of Dasypus sabanicola were found to have a typical mammalian distribution of lymphoid cells in thymus, spleen, lymph nodes and blood. Their complement was active in bactercidal, protozoan immobilization and haemolytic systems. Blood lymphocytes responded to phytohaemagglutinin and to pokeweed mitogen. Sensitization with ovalbumin in CFA resulted in the production of circulating precipitins; strong Arthus reactions were detectable in the sensitized animals. Responses of cell-mediated immunity to DNCB and to M. tuberculosis were very discrete. Heat-killed M. leprae elicited granulomatous reactions characterized by microscopic necrosis, but without abundant lymphocytic infiltration; skin tests and lymphocytic transformation were generally negative in the animals injected with M. leprae.

Immunologic responses in patients with lepromatous leprosy.

Immunologic responses were measured in 46 patients with lepromatous leprosy. These patients were not distinguishable from controls on the basis of responses to soluble intradermal antigens, sensitization to contactants, peripheral blood T- and B-cell percentages, in vitro lymphocyte responses to a mitogen, or the prevalence of autoantibodies. Generalized immunologic abnormalities in patients with lepromatous leprosy are neither predisposing causes nor necessary accompaniments of lepromatous leprosy, but are probably remote sequellae of the illness. By implication, the generalized immunologic abnormalities reported in other diseases are likely to be remote sequellae of the particular illness.

Immunologic responses in patients with lepromatous leprosy

Immunologic responses were measured in 46 patients with lepromatous leprosy. These patients were not distinguishable from controls on the basis of responses to soluble intradermal antigens, sensitization to contactants, peripheral blood T- and B-cell percentages, in vitro lymphocyte responses to a mitogen, or the prevalence of autoantibodies. Generalized immunologic abnormalities in patients with lepromatous leprosy are neither predisposing causes nor necessary accompaniments of lepromatous leprosy, but are probably remote sequellae of the illness. By implication, the generalized immunologic abnormalities reported in other diseases are likely to be remote sequellae of the particular illness.

Evaluation of cell mediated immunity in the histopathologic spectrum of leprosy using lymphocyte transformation test.

Lymphocyte transformation in response to PHA, M. leprae and BCG with the use of measurements of 3H-thymidine uptake, was studied in 10 normal controls, and 71 leprosy patients of different types histologically classified according to the Ridley-Jopling scale. Lepromin and PPD tests were done in each one of them. It was found that there was a generalized depression of immune responsiveness to PHA in all forms of leprosy. The immune responsiveness of lymphocytes to M. leprae continuously and gradually increases from the lepromatous (LL) towards the tuberculoid (TT) end of the spectrum. The loss of immune response of lymphocytes from lepromatous patients to M. leprae is specific as evidenced by their capacity to respond selectively to BCG when PPD-positive, irrespective of their place in the leprosy spectrum.

Leprosy XII. Quantitative analysis of thymus-derived lymphocyte response to phytohemagglutinin in leprosy.

The immune status of various leprosy patients was evaluated by using a micromethod to evaluate lymphocyte responses to phytohemagglutinin (PHA). In our study, whole blood was used and the degree of response to PHA stimulation was expressed in terms of unit volume of blood. A markedly decreased response to PHA stimulation was noted in patients with active lepromatous leprosy. Patients with active lepromatous leprosy who have been proved drug (DDS) resistant showed less response than did those of drug sensitive patients with active lepromatous disease, while the patients with active lepromatous leprosy complicated by erythema nodosum leprosum (ENL) showed higher response than did those of patients with no complicated ENL. Comparing the results obtained to those obtained using other methods for T cell analysis indicates that these results reflect the number of T lymphocytes in the leprosy patient. Thus, this simple method is of value in assaying the presence and responses of T lymphocytes in the leprosy patient.