Yeldur P. Venkatesh

Objective: Guduchi [Tinospora cordifolia (Willd.) f. and Thoms.], a rasayana (rejuvenator) in the traditional system of Indian medicine (Ayurveda), is known for its diverse bioactivities. The aim of this study was to isolate the immunomodulatory protein (ImP) from commercial guduchi churna (stem powder) and characterize it. Methods: Guduchi churna extract following 80% ammonium sulfate precipitation was chromatographed on Q-Sepharose. Purified guduchi ImP was evaluated for its lymphoproliferative and macrophage activation properties, structural relatedness to certain plant lectins, amino acid composition, stability to trypsin, and N-terminal sequencing. Results: The purified protein, obtained in a yield of 140[ ]mg/100[ ]g guduchi churna, showed a molecular mass of [ ] kDa by SDS-PAGE. Guduchi ImP (10 [ ]g) showed seven-fold increase over control in mitogenic activity of murine splenocytes, and a four-fold increase over control in nitric oxide (NO) release from murine peritoneal exudates cells (PECs). These activities were abolished in pronase-treated guduchi ImP. Guduchi ImP does not agglutinate rabbit erythrocytes. Rabbit antiserum to guduchi stem ImP strongly reacted with purified guduchi ImP, and did not recognize common plant lectins (concanavalin A (Con A), poke weed mitogen (PWM) and garlic lectin). Amino acid composition of guduchi ImP shows high content of acidic amino acids, serine (12.4%) and cysteine (10.2%); guduchi ImP is highly stable to trypsin and has a blocked N-terminus. Conclusion: Guduchi ImP is an acidic, non-lectin ImP with a high content of serine and cysteine, and appears to have an immense potential for future structural, immunological, and therapeutic studies.

Dietary food components have the ability to affect immune function; following absorption, specifically orally ingested dietary food containing lectins can systemically modulate the immune cells and affect the response to self- and co-administered food antigens. The mannose-binding lectins from garlic (Allium sativum agglutinins; ASAs) were identified as immunodulatory proteins in vitro. The objective of the present study was to assess the immunogenicity and adjuvanticity of garlic agglutinins and to evaluate whether they have adjuvant properties in vivo for a weak antigen ovalbumin (OVA). Garlic lectins (ASA I and ASA II) were administered by intranasal (50 days duration) and intradermal (14 days duration) routes, and the anti-lectin and anti-OVA immune (IgG) responses in the control and test groups of the BALB/c mice were assessed for humoral immunogenicity. Lectins, co-administered with OVA, were examined for lectin-induced anti-OVA IgG response to assess their adjuvant properties. The splenic and thymic indices were evaluated as a measure of immunomodulatory functions. Intradermal administration of ASA I and ASA II had showed a four-fold and two-fold increase in anti-lectin IgG response, respectively, vs. the control on day 14. In the intranasal route, the increases were 3-fold and 2.4-fold for ASA I and ASA II, respectively, on day 50. No decrease in the body weights of animals was noticed; the increases in the spleen and thymus weights, as well as their indices, were significant in the lectin groups. In the adjuvanticity study by intranasal administration, ASA I co-administered with ovalbumin (OVA) induced a remarkable increase in anti-OVA IgG response (~six-fold; p < 0.001) compared to the control, and ASA II induced a four-fold increase vs. the control on day 50. The results indicated that ASA was a potent immunogen which induced mucosal immunogenicity to the antigens that were administered intranasally in BALB/c mice. The observations made of the in vivo study indicate that ASA I has the potential use as an oral and mucosal adjuvant to deliver candidate weak antigens. Further clinical studies in humans are required to confirm its applicability.

N. Krithika sup 1 /sup venkatyp@yahoo.com S.N. Pramod sup 1 /sup P.A. Mahesh sup 2 /sup Y.P. Venkatesh sup 1 /sup

The association between grass pollen sensitization and food allergy to tomato is of great interest. We report here, the first such study in Indian population. We investigated 246 allergic rhinitis / asthma patients by diagnostic case history and skin prick test (SPT); grass pollen mix, tomato extract and purified tomato profilin were used for SPT. Tomato profilin was purified by affinity chromatography, and analyzed by HPLC (95% purity) and SDS-PAGE (14 kDa). We observed that 38% of the patients had sensitization to both grass pollen and tomato fruit, of which 92% were sensitized to tomato profilin. Among patients with a history of food allergy to tomato fruit, the association was more pronounced (66%). Tomato profilin appears to be an important cross-sensitizing panallergen in respiratory allergic patients in the Indian subcontinent.