Research

Antibody responses to the merozoite surface protein-1 complex in cerebral malaria patients in India

Naomi W Lucchi¹ , Jon Eric Tongren¹ , Vidhan Jain² , Avinash C Nagpal³ , Christian W Kauth⁴ , Ute Woehlbier⁴ , Hermann Bujard⁴ , Aditya P Dash⁵ , Neeru Singh² , Jonathan K Stiles⁶ and Venkatachalam Udhayakumar^1,7

¹  Malaria Branch, Division of Parasitic Diseases, National Center for Zoonotic, Vector-Borne and Enteric Diseases, Coordinating Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA, USA

²  National Institute of Malaria Research, Regional Medical Research Center for Tribals, Indian Council of Medical Research (ICMR), Jabalpur, India

³  Nethaji Subash Chandra Bose (NSCB) Medical College, Jabalpur, India

⁴  Zentrum fuer Molekulare Biologie Heidelberg (ZMBH), Universitaet Heidelberg, Im Neuenheimer Feld 282, D-69120 Heidelberg, Germany

⁵  National Institute of Malaria Research, ICMR, New Delhi, India

⁶  Morehouse School of Medicine, Atlanta, GA, USA

⁷  Atlanta Research and Education Foundation, Decatur, GA, USA

author email corresponding author email

Malaria Journal 2008, 7:121doi:10.1186/1475-2875-7-121

Published:	4 July 2008

Abstract

Background

Plasmodium falciparum infection causes cerebral malaria (CM) in a subset of patients with anti-malarial treatment protecting only about 70% to 80% of patients. Why a subset of malaria patients develops CM complications, including neurological sequelae or death, is still not well understood. It is believed that host immune factors may modulate CM outcomes and there is substantial evidence that cellular immune factors, such as cytokines, play an important role in this process. In this study, the potential relationship between the antibody responses to the merozoite surface protein (MSP)-1 complex (which consists of four fragments namely: MSP-1₈₃, MSP-1₃₀, MSP-1₃₈ and MSP-1₄₂), MSP-6₃₆ and MSP-7₂₂ and CM was investigated.

Methods

Peripheral blood antibody responses to recombinant antigens of the two major allelic forms of MSP-1 complex, MSP-6₃₆ and MSP-7₂₂ were compared between healthy subjects, mild malaria patients (MM) and CM patients residing in a malaria endemic region of central India. Total IgG and IgG subclass antibody responses were determined using ELISA method.

Results

The prevalence and levels of IgG and its subclasses in the plasma varied for each antigen. In general, the prevalence of total IgG, IgG1 and IgG3 was higher in the MM patients and lower in CM patients compared to healthy controls. Significantly lower levels of total IgG antibodies to the MSP-1_f38, IgG1 levels to MSP-1_d83, MSP-1₁₉ and MSP-6₃₆ and IgG3 levels to MSP-1_f42 and MSP-7₂₂ were observed in CM patients as compared to MM patients.

Conclusion

These results suggest that there may be some dysregulation in the generation of antibody responses to some MSP antigens in CM patients and it is worth investigating further whether perturbations of antibody responses in CM patients contribute to pathogenesis.