Application of chemical immunomodulators to the treatment of cancer and AIDS

Immunomodulatory Effects of the Meretrix Meretrix Oligopeptide (QLNWD) on Immune-Deficient Mice

The aim of this study was to explore the immunomodulatory effects of the Meretrix meretrix oligopeptide (MMO, QLNWD) in cyclophosphamide (CTX)-induced immune-deficient mice. Compared to untreated, CTX-induced immune-deficient mice, the spleen and thymus indexes of mice given moderate (100 mg/kg) and high (200 mg/kg) doses of MMO were significantly higher (p < 0.05), and body weight loss was alleviated. Hematoxylin-eosin (H&E) staining revealed that MMO reduced spleen injury, thymus injury, and liver injury induced by CTX in mice. Furthermore, MMO boosted the production of immunoglobulin G (IgG) and hemolysin in the serum and promoted the proliferation and differentiation of spleen T-lymphocytes. Taken together, our findings suggest that MMO plays a vital role in protection against immunosuppression in CTX-induced immune-deficient mice and could be a potential immunomodulatory candidate for use in functional foods or immunologic adjuvants.

Selenium nanoparticle-enriched Lactobacillus brevis causes more efficient immune responses in vivo and reduces the liver metastasis in metastatic form of mouse breast cancer

BACKGROUND AND THE PURPOSE OF THE STUDY

Selenium enriched Lactobacillus has been reported as an immunostimulatory agent which can be used to increase the life span of cancer bearing animals. Lactic acid bacteria can reduce selenium ions to elemental selenium nanoparticles (SeNPs) and deposit them in intracellular spaces. In this strategy two known immunostimulators, lactic acid bacteria (LAB) and SeNPs, are concomitantly administered for enhancing of immune responses in cancer bearing mice.

METHODS

Forty five female inbred BALB/c mice were divided into three groups of tests and control, each containing 15 mice. Test mice were orally administered with SeNP-enriched Lactobacillus brevis or Lactobacillus brevis alone for 3 weeks before tumor induction. After that the administration was followed in three cycles of seven days on/three days off. Control group received phosphate buffer saline (PBS) at same condition. During the study the tumor growth was monitored using caliper method. At the end of study the spleen cell culture was carried out for both NK cytotoxicity assay and cytokines measurement. Delayed type hypersensitivity (DTH) responses were also assayed after 72h of tumor antigen recall. Serum lactate dehydrogenase (LDH) and alkaline phosphatase (ALP) levels were measured, the livers of mice were removed and prepared for histopathological analysis.

RESULTS

High level of IFN-γ and IL-17 besides the significant raised in NK cytotoxicity and DTH responses were observed in SeNP-enriched L. brevis administered mice and the extended life span and decrease in the tumor metastasis to liver were also recorded in this group compared to the control mice or L.brevis alone administered mice.

CONCLUSION

Our results suggested that the better prognosis could be achieved by oral administration of SeNP-enriched L. brevis in highly metastatic breast cancer mice model.

Synthesis of new pyrrolo[1,2-d][1,2,4]triazines and thiazolo[3,4-d][1,2,4]triazines as immunostimulating agents

Four pyrrolo[1,2-d][1,2,4]triazines and four thiazolo[3,4-d][1,2,4]triazines were synthesized from trans-4-hydroxy-L-proline and L-thiaproline, respectively. The synthetic route involved formation of hydrazides followed by cyclization with orthoesters. The proliferative response to human lymphocyte mitogen (phytohemagglutinin) revealed significant immunostimulant activity for all test drugs. Furthermore, some triazine derivatives were effective to activate production of free oxygen radical by phagocytes in response to stimulation by opsonized zymosan.

A proposed new strategy of immunotherapy for Alzheimer's disease

Current data on the involvement of the immunological system in the pathogenesis of Alzheimer's disease (AD) are discussed, and results of immunotherapy for the disease are provided. Hypotheses on immune aging as a risk factor for AD, and a suggested new treatment strategy, are presented and discussed.

Effect of methionine enkephalin on natural killer cell and cytotoxic T lymphocyte activity in mice infected with influenza A virus

Methionine enkephalin (Met-Enk) was evaluated for efficacy as an immune activator and potential therapeutic agent in influenza A/NWS/33 (H1N1) viral infections in female BALB/C mice. Influenza infection was induced intranasally with an approximate 90% lethal dose of virus and mice were treated intraperitoneally with doses of 10, 3 and 1 mg/kg/day, with treatments given 24 h pre-, 24 h post- and 72 h post-virus exposure. Splenocytes were assayed for natural killer cell (NK) and cytotoxic T lymphocyte (CTL) activity at time periods 76, 96 and 120 h post virus exposure. The 10 mg/kg dosage level significantly increased both CTL and NK activity at all time periods assayed. Other treatment schedules included single doses of 20, 10 and 3 mg/kg/day Met-Enk at either 24 h post- or 72 h post-virus exposure, with highly significant increases in NK and CTL activity noted after the latter treatment. The results of this study demonstrate the immunomodulatory effects of Met-Enk on NK and CTL in influenza infected mice and suggest a potential for therapeutic applications.