Sequence diversity of the C-terminal region of Plasmodium falciparum merozoite surface protein 1 in southern Iran.

The C-terminal region of the merozoite surface protein 1 (MSP-1) of Plasmodium falciparum is a strong vaccine candidate as it is associated with immunity to the parasite. This corresponds approximately to the conserved 17th block of the gene and is composed of two EGF- like domains. These domains exhibit only four single amino acid substitutions which show several potential variants in this region of the gene. As the variations might be important for a regional vaccine design, a study was carried out to determine the variations present in P. falciparum isolates from southern Iran. Besides the usual E-T-S-R-L and the Q-K-N-G-F types, we found Q-T-S-R-L, E-K-N-G-F, E-T-S-G-L, Z-T-S-G-L and Z-T-S-R-L types, where Z was E or Q signifying the presence of mixed clones in single isolates.

Patterns of co-association of C-reactive protein and nitric oxide in malaria in endemic areas of Iran

In addition to numerous immune factors, C-reactive protein (CRP) and nitric oxide (NO) are believed to be molecules of malaria immunopathology. The objective of this study was to detect CRP and NO inductions by agglutination latex test and Griess microassay respectively in both control and malaria groups from endemic areas of Iran, including Southeastern (SE) (Sistan & Balouchestan, Hormozgan, Kerman) and Northwestern (NW) provinces (Ardabil). The results indicated that CRP and NO are produced in all malaria endemic areas of Iran. In addition, more CRP and NO positive cases were observed amongst malaria patients in comparison with those in control group. A variable co-association of CRP/NO production were detected between control and malaria groups, which depended upon the malaria endemic areas and the type of plasmodia infection. The percentage of CRP/NO positive cases was observed to be lower in NW compare to SE region, which may be due to the different type of plasmodium in the NW (Plasmodium vivax) with SE area (P. vivax, Plasmodium falciparum, mixed infection). The fluctuations in CRP/NO induction may be consistent with genetic background of patients. Although, CRP/NO may play important role in malaria, their actual function and interaction in clinical forms of disease remains unclear.

Molecular epidemiology of malaria in endemic areas of Iran.

In this study, 333 blood samples of malaria cases positive by microscopic test (70.6% male and 29.4% female, p<0.05) were investigated. The group included 55 cases (16.52%) from Minab (Hormozgan Province), 116 cases (34.82%) from Iranshahr (Sistan-Baluchesta Province) and 162 cases (48.65%) from Kahnouj (Kerman Province). The results showed 244 cases (73.27%) were diagnosed as P. vivax, 87 cases (26.13%) P. falciparum and 2 cases (0.6%) showed a mixed infection of both Plasmodia. In a molecular study of the same samples using nested-polymerase chain reaction (nested-PCR), 185 cases (55.6%) were P. vivax, 50 cases (15%) P. falciparum and 95 cases (29%) both Plasmodia. Comparing the two methods used in this study, the highest rate of infection was found to be P. vivax. However, the rate of mixed infections (0.6% microscopy, 29% nested-PCR) varied and depended on the assay used. This indicated that the sensitivity of nested-PCR was greater than microscopic examination, especially for the detection of mixed-infections (p<0.05) in the current malaria epidemiology study.