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Multiantigenic Vaccination in Malaria

There is a one obvious alternative approach to developing artificial immunity against multiple antigenic forms of parasites. Instead of simultaneous administration of complete repertoir of antigenic forms proposed by my article Toward Understanding of Vaccines it is possible to try multiple sequential exposures to these forms as well.

Indeed, for example, commond cold virus has just about two hundred antigenic forms. Every form ensure a one-week-long illness and, therefore, after catching all forms sequentially resulting in two handred weeks ( four years) of continuous sneezing we may become at last immune to common cold. I am afraid, this does not sounds well in the case of common cold, yet the malaria seems to be a unique infection for which this approach looks much much more attractive.

During natural course of infection, one antigenic forms of malaria are rapidly replaced by others thanks to parasite's ability of fast antigenic variation and to numerous opportunities of superinfection through insects' bites.
So, acquaintance of patients with the available repertoire of malaria's antigenic forms proceeds much more extensively. And the fact is that after some time of suffering from malaria people acquire substantial immunity against it, which nevertheless disappears after moving into other geographical location - it is easy to suggest that there may be encountered new antigenic forms leadig to full blown disease.

Unfortunately, this obvious explanation of natural immunity to malaria is not a mainstream one. Officially, its mechanism is considered to be a complete mystery. It allows to cling to the same utopic approaches to malaria vaccines attempting rising immunity against some magic antigens. And, of course, with the same result.

Yet, I have received a message from Barend Mons about his relevant a 'not taken very seriously' work
(B.Mons - A Live Attenuated Malaria Vaccine: Science or Fiction? - Acta Leiden (1991) v.60(1) p.180)
devoted mostly to arguing against the recombinant malaria vaccines. He use an interesting metaphor for clarifying the intrinsic flaws in these 'clean' recombinant vaccines:
'Essentially saying that when we moved from shooting at flying birds from the hip (not really understanding how our multi-antigenic vaccines work) to single bullets, we did not take the time (nor did we allocate sufficient funds) to construct a telescope on our rifle (understanding of the mechanism of protection to enable aiming at induction of the exact proper arm(s) of the immune system). In my field (malaria) this has led to a quite disastrous situation, with too many antigens to handle and people are more and more trying to put those back together. In the best of cases we might then be able to reconstruct a molecular copy of a dead parasite, composed entirely out of recombinant molecules........with your hypothesis being true this would be a fairly wasteful exercise.'

He also mentiones experiment which looks as a feasibility study of the approach suggested above. Experimental animals were infected with malaria and then were received sub curative treatment with drugs. This makes the parasite to multiply long enough in the host without serious pathology expressing the full repertoire of antigenic variants needed to cause reasonable protection. Finally, this approach may result in 'solid immunity'. This approach has a rather obvious drawbacks: first, long persistence of malaria parasite may be dangerous, and, second, the intensity of elicited immunity seems to resemble that provided by irradiated sporozoites - i.e, by killed vaccine.

Apparently, Dr. Mons does not support my explanation of classical attenuated vaccines. Yet, though this problem seems to be the most scientifically interesting part of my paper, in the case of malaria, certainly, this part is superfluous having no practical importance. There are too many other (and more direct) reasons to substantiate idea of multiantigenic vaccination against malaria.